March 17, 2005

METRO NY / NJ Pediatric Board Review Course

Pediatric NephrologyMay, 2010

Leonard G. Feld MD PhDLevine Children’s Hospital

Charlotte, NC

March 17, 2005

March 17, 2005

For the ExamFluid and Electrolyte MetabolismA. Composition of body fluids -Intracellular,

extracellular, Electrolytes (sodium, potassium, chloride), Protein

B. Acid-base physiology -Normal mechanisms and regulation, Acidosis, alkalosis

C. Electrolyte abnormalities - Sodium – Hypernatremia; Hyponatremia; Potassium Hyperkalemia; Hypokalemia; Chloride imbalance

D. Disease states, specific therapy - Pyloric stenosis, gastroenteritis, acute renal

failure, shock, SIADH, Cystic fibrosis, Dehydration, Hyperosmolar non-ketotic coma

March 17, 2005

For the ExamRenal DisordersA. Normal function, proteinuria, hematuria, persistent microscopic hematuria,

causes of gross and microscopic hematuria, nonhematogenous etiology of red urine,dysuria,

B. Incontinence - Nocturnal, functional, daytime incontinence, C. Congenital - Renal dysplasia, unilateral multicystic dysplastic kidney,

autosomal dominant polycystic kidney disease, autosomal recessive polycystic kidney disease, Juvenile nephronophthisis, Renal agenesis

D. Abnormalities of the collecting system, kidney, and bladder – Hydronephrosis, Hydroureter and megaureter, Ureterocele, Vesicoureteral reflux,

E. Abnormalities of the urethra - Posterior urethral valves, Urethral strictureF. Hereditary nephropathy - Familial nephritis, Congenital nephrotic syndromeG. Acquired - Infection of the urinary tract (Pyelonephritis, Cystitis), acute

glomerulonephritis, Nephrotic syndrome, Hemolytic-uremic syndrome, Henoch-Schoenlein purpura,IgA nephropathy

H. Renal failure - Prerenal failure, Intrinsic renal failure , chronic renal failure, I. Other - Trauma, renal injuries, Urethral injury, Toxins, Renal stones, Renal

tubular acidosis, Hereditary conditions with renal manifestations, Nephrogenic diabetes, insipidus, Cystinosis

J. Hypertension – General, Renal, Vascular, Adrenal, Pheochromocytoma, Cushing syndrome, Miscellaneous causes, Essential hypertension, Administration of drugs, Traction on legs

March 17, 2005

Outline• Fluid and Electrolyte abnormalities

– Maintenance– Dehydration– Electrolyte Disturbances– Acid Base Problems

• Renal– Hematuria– Proteinuria– Hypertension– Urinary tract infections– Glomerulonephritis

March 17, 2005

Fluids and Electrolytes

March 17, 2005

Electrolyte Composition of Body Fluid Compartments

March 17, 2005

BODY WATER DISTRIBUTION

TOTAL BODY WATER (TBW)0.6 x Body Weight (BW)

EXTRACELLULAR FLUID (ECF)

0.2 x BW

INTRACELLULAR FLUID (ICF)0.4 x BW

Interstitial Fluid Plasma ¾ of ECF ¼ of ECF

March 17, 2005

Clinical AssessmentFluid Deficit

Clinical Status

Clinical Assessment

Mild ( 5%)

50 cc/kg Compensated Thirsty, HR, Normal BP tears, slightly dry mucosa, alert/restless, [urine]

Moderate (10%)

100 cc/kg Decompensated Very dry mucosa, < skin turgor, sunken eyes, deep resp, weak pulses, cool extremities, oliguria

Severe (15%)

150 cc/kg Shock Intense thirst, BP, cap refill > 3 sec, weak pulses, apnea/rapid breathing, coma, anuria

March 17, 2005

Maintenance Requirements

Body wt 0-10 kg 10-20 kg 20 kg

TBW 100 ml/kg 1000 ml +50 ml/kg for each kg > 10kg

1500 +20 ml/kg for each kg > 20kg

Na+ 3 mEq/kg 3 mEq/kg 3 mEq/kg

K+ 2 mEq/kg 2 mEq/kg 2 mEq/kg

Cl- 5 mEq/kg 5 mEq/kg 5 mEq/kg

March 17, 2005

Fluid and Calories• Kidney losses is about 45-75 mL/100 calories

expended; • Sweat losses usually 0; • Stool losses is about 5-10 mL / 100 calories

expended, • Insensible losses (skin ~ 30 mL + Respiratory ~

15 mL ) is about 45 mL/100 calories expended

SO - 100 mL of total daily water losses = 100 calories expended per day or 1 mL = 1 calorie.

March 17, 2005

DefcitType of Dehydrationbased on serum [Na] in

mEq/L

Water (mL/kg)

Sodium (mEq/kg)

Potassium (mEq/kg)

Isonatremic [Na] 130-150 100-120 8-10 8-10

Hyponatremic [Na] < 130 100-120 10-12 8-10

Hypernatremic [Na] > 150 100-120 2-4 0-4

March 17, 2005

Case 1 Dehydration

A four month-old infant presents to her pediatrician with a four to five day history of low grade fever (38-38.5oC), numerous watery diarrhea and decreased activity.

Since the child refused to take her usual breast milk volume or solid foods, the mother and grandmother substituted non-carbonated soda (Coca-cola, ginger ale, apple juice or orange juice will have ~550-700 mOsm/kg H2O) with less than 5 mEq/L of sodium), and “sweet” (sugar added) iced tea.

Over the last 12 hours there were a few episodes of emesis and there were less wet diapers.

March 17, 2005

On examination the child was lethargic, dry mucous membranes, no tears, sunken eyeballs, and reduced skin

turgor.

Vitals signs were the following: Blood pressure 74/43 mmHg; Temperature of 38oC, respiratory rate of 36 per minute and

pulse of 175 beats per minute. The weight was 6 kg. Weight at the time of her immunization 7 days ago was 6.6 kg.

There were no other significant findings.

With the magnitude of dehydration and lethargy, the decision by the clinician was to initiate parenteral fluid replacement

rather than oral rehydration therapy. The child was admitted to the hospital with diagnosis of dehydration. On admission the

laboratory studies were as follows:

March 17, 2005

Sodium 124 mEq/L, chloride 94 mEq/L, potassium 4 mEq/L bicarbonate (or total COs) was 12 mEq/L, serum creatinine 0.8 mg/dL blood urea nitrogen 40 mg/dL, blood glucose 70 mg/dL;

complete blood count was normal except for a hemocrit of 38%

Urinalysis/ chemistries: specific gravity of 1.030, trace protein, no blood or glucose, small ketones; urine creatinine 40

mg/dL and sodium 15 mEq/L;

Fractional excretion of sodium (FENa)( [urine sodium x serum creatinine]/ [serum sodium x urine

creatinine] x 100%) = ([15 mEq/L x 0.8 mg/dL] / [129 mEq/L x 40 mg/dL]) = 0.23%

Normal values for FENa = ~ 1-2%; decreased renal perfusion (dehydration, decreased intravascular volume) < 1%

March 17, 2005

Hyponatremia

• Serum [Na+] < 130 mEq/L• Water shifts into cells – lower ECF volume• <125 mEq/L – nausea and malaise• < 120 mEq/L – headache, lethargy, • <115 mEq/L – seizure and coma

March 17, 2005

Loss of hypertonic Fluid and Sodium from the ECF secondary to Dehydration

35 Na 64 K

15 Na55 K

10 Na

15 Na54 K

10 Na

280

0

280

0

280

0

258

0

200

0

258

0

0.25 Liters 0.40 Liters

0.15 Liters 0.40 Liters

0.116 Liters 0.434 Liters

NORMAL

AFTER LOSS

AFTER OSMOTIC ADJUSTMENT

NORMAL ECF NORMAL ICF

mOsm/L

400

0

Loss0.10 LIters

10 K10 Na

March 17, 2005

Question 1: What is the appropriate parenteral solution

A. 5% dextrose + 0.45% isotonic saline + 40 mEq KCl /L

B. 0.45% isotonic saline + 40 mEq KCl /L

C. 0.9% isotonic saline + 40 mEq KCl /L

D. 5% dextrose + 40 mEq KCl /L

E. 5% dextrose + 0.2% isotonic saline

March 17, 2005

Assessment

The information suggest hyponatremic dehydration secondary to extrarenal losses from diarrhea with administration by the family of hypotonic or dilute fluids.

The child has lost proportionally more sodium than water or a relatively hypertonic fluid loss. The result is a lower extracellular fluid osmolality compared to the intracellular fluid osmolality. The magnitude of the dehydration is about 10% or moderate to severe. The pre-illness weight was 6.6 kg with a current weight of 6 kg or a 0.6 kg loss over the last week.

March 17, 2005

Oral RehydrationThe decision by the clinician was to initiate

parenteral fluid replacement rather than oral rehydration therapy. The relative contraindications for oral rehydration therapy would include a young infant less than 3-4 months of age, the presence of impending shock or markedly impaired perfusion (increased capillary refill time/decreased skin turgor), inability to consume oral fluids due to intractable vomiting, marked irritability or lethargy/unresponsiveness or the judgment of the clinician.

March 17, 2005

Therapeutic Plan 1 Volume, Deficit, Electrolyte Calculations

Phases emergent or acute phase – isotonic fluid infusion

over about one hour; replacement phase – over 24 hrs unless there are

on-going losses which are not replaced adequately in the first day of treatment;

maintenance phase- day 2 continuing to home management.

March 17, 2005

Emergent PhaseEmergent or acute phase • Over about one hour - reestablish circulatory volume to prevent

prolonged loss of perfusion to the key organs such as kidney, brain, gastrointestinal tract, etc.

• Fluid choices would be isotonic (0.9%) saline (normal saline) or another isotonic /hypertonic solution such as 5% albumin, Ringer’s lactate, or a plasma preparation.

With the availability of isotonic saline, this is the usual fluid choice. Weight (kg) x fluid bolus of 20 mL/kg over 30 -60 minutes.

(If the patient was in shock fluid delivery more rapid infusion to prevent organ failure.)

6 kg x 20 mL = 120 mL over 30-60 minutes.only replaces 20% of the losses [total losses 600 ml]

March 17, 2005

Approach

For this 6.6 kg infant Maintenance requirements for 24 hours

Water 100 mL / kg x 6.6 kg = 660 mLSodium 3 mEq / 100 mL x 660 mL = 20 mEqPotassium 2 mEq / 100 mL x 660 mL = 13 mEq

March 17, 2005

Approach 1Type of Dehydration*based on serum [Na] in mEq/L

Water (mL/kg) Sodium (mEq/kg) Potassium (mEq/kg)

Isonatremic [Na] 130-150 100-120 8-10 8-10

Hyponatremic [Na] < 130 100-120 10-12 8-10

Hypernatremic [Na] > 150 100-120 2-4 0-4

• Isonatremic dehydration is the most common accounting for 70-80% of infants and children;• hypernatremic dehydration accounts for about 15%, and • hyponatremic dehydration for about 5-10% of cases.

For this 6 kg infant with hyponatremic dehydration at 10%Deficits for 24 hours

Water Pre-illness weight – Illness weight = 6.6 – 6 kg = 0.6 kg = 600 mLSodium 10 mEq x 6.6 kg = 66 mEqPotassium 8 mEq x 6.6 kg = 53 mEq

Total First 24 hours Requirements

The total amount of maintenance and deficit amounts are given 50% over the first 8 hours and the remainder over the next 16 hours.

March 17, 2005

ApproachFor this 6.6 kg infant Maintenance requirements for 24 hours

Water 100 mL / kg x 6.6 kg = 660 mLSodium 3 mEq / 100 mL x 660 mL = 20 mEqPotassium 2 mEq / 100 mL x 660 mL = 13 mEq

For this 6 kg infant with hyponatremic dehydration at 10%Deficits for 24 hoursWater Pre-illness weight – Illness weight = 6.6 – 6 kg = 0.6 kg = 600 mL

Sodium 10 mEq x 6.6 kg = 66 mEqPotassium 8 mEq x 6.6 kg = 53 mEq

March 17, 2005

Component of Therapy Water Sodium Potassium Hourly RateRound number up or down to the nearest 5 increment

Acute Phase 120 18 (154mEq/L x 0.12 L)

0 Entire amount over 20-60 min

Maintenance 660 20 13

Deficit 600 66 53

Ongoing losses of diarrhea of vomiting*

TOTAL 1280 104 66

Emergent Phase Therapy (120) (18)

FINAL THERAPY Hrs 1- 8 Hrs 9-24

1160 580 580

86 43 43

66 33 33

72 mL / hr36 mL / hr

March 17, 2005

Gastrointestinal losses tend to resolve or decrease significantly following IV therapy. If it does continue these losses will need to be added to the ongoing

loss

For each liter of IV solution there would be 43 mEq / 0.58 L = ~75 mEq Per LiterFluid selection – 5% dextrose + 0.45% isotonic saline + 40 mEq KCl /L

Potassium concentration is ~ 30- 40 mEq/L (it should not exceed 40 mEq/L without close

intensive care monitoring). Some recommend 20-25 mEq/L - potassium stores will be replenished when the

child restart oral feeds.

The 5% dextrose provides 50 grams of carbohydrate per liter of 50 grams x ~ 4 calories per gram = 200 calories. This would be about 20% of the daily caloric intake which is sufficient to prevent protein breakdown over a short treatment

period (less than one week).

Closing thoughts

March 17, 2005

Case 2

A ten month-old infant presents to the pediatric emergency room with a generalized tonic clonic seizure. The child had a fever to 39-400C for the past 24-36 hours, lethargy, vomiting, decreased

oral intake, less wet diapers. The child did not receive Prevnar (pneumococcal vaccine).

On exam - ill and irritable resisting any movement, VS: BP 94/58mmHg; Temperature of 39oC, respiratory rate of 40; pulse 175 beats. The weight 10 kg. There were no focal neurological

findings. The impression was meningitis, probable pneumococcal and hyponatremia.

March 17, 2005

On admission labs: Sodium 126 mEq/L, chloride 95 mEq/L, potassium 4 mEq/L

Bicarbonate (or total COs) 19 mEq/L Serum creatinine 0.3 mg/dL blood urea nitrogen 6 mg/dL, uric acid of 2.4 mg/dL, blood glucose 85 mg/dL; WBC 26,000 /mm3 with 255 immature cells (bands). LP protein 140 mg/dL, glucose 30 mg/dL and 2000 leukocytes /mm3 with more than 80% PMNs. Blood and urine culture pending. Serum osmolality 262 mOsm/kg

[2 x serum sodium + glucose/18 + BUN/1.8 = 252 + 5 + 4 = 261].

Urinalysis/ chemistries: specific gravity of 1.018 (estimated osmolality = 720 mOsm/kg), no blood, protein or glucose, small ketones; urine sodium 100 mEq/L, urine creatinine 15 mg/dL; fractional sodium excretion (FENa) – 1.6 %

March 17, 2005

Question 2: What is the most likely diagnosis for the Hyponatremia

A. Diabetes Insipidus

B. Water Intoxication

C. Thyroid insufficiency

D. Syndrome of inappropriate antidiuretic hormone secretion

E. Glucocorticoid insufficiency

March 17, 2005

TumorsBronchogenicAdenoCa DuodenumAdenoCa PancreasCa Of UreterHodgkin'sThymomaAcute LeukemiaLymphosarcomaHistiocyticLymphoma

Chest DisordersInfection Tb Bacterial Mycoplasma Viral FungalPositivePressure VentilationDec Left Atrial Pressure Pneumothorax Atelectasis Asthma Cystic fibrosis Mitral Valve Commissurotomy PDA Ligation Malignancy

CNS DisordersInfection / Inflammatory TB Meningitis Bacterial Meningitis EncephalitisHead TraumaSubarachnoid hemorrhageHypoxia-IschemiaAcute PsychosisBrain Tumor / Mass LesionsMiscellaneous Guillain-Barré syndrome Spinal Cord lesions VA Shunt Obstruction / hydrocephalus AcuteIntermittent Porphyria Cavernou Sinus Thrombosis Stress / Extensive Exercise (running a marathon, etc.)Idiopathic

DrugsAdenineArabinosideAmitriptylineBarbituratesCarbamazepineChlorpropamideClofibrateColchicineDiureticsFluphenazineIsoproterenolMorphineNicotineTricyclicsVinblastineVincristine

Causes of SIADH

March 17, 2005

Criteria

1) Hypotonic hyponatremia. 2) Inappropriate urine osmolality compared to plasma osmolality. In patients with an medical condition associated with the occurrence of SIADH, a urine osmolality greater than maximal dilution (75-125 mosm/L) and a low plasma osmolality is “inappropriate” to state of water balance. 3) Absence of thyroid, adrenal, cardiac, or renal disease. 4) Absence of volume contraction. 5) High urinary sodium concentration (increased FENa).

March 17, 2005

Information suggest meningitis with SIADH.

Neurological findings with hyponatremia suggests this diagnosis. No evidence of volume depletion or expansion/excess of the extracellular fluid compartment. Hyponatremia with a decreased serum osmolality (effective osmolality/tonicity) with a urine osmolality which is not maximally dilute (< ~125 mOsm/kg) without evidence of renal, thyroid or adrenal disease is consistent with SIADH.

Additional info: low serum uric acid and BUN in the face of clinical euvolemia, elevated FENa (> 1%) – inconsistent with hypovolemia when the FENa should be < 1%, lack of evidence of diuretic use, pseudohyponatremia (secondary to increased plasma proteins or lipids) or hypertonic hyponatremia (hyperglycemia or mannitol infusions).

March 17, 2005

KEY POINTS ON SIADH• SIADH will not resolve until the underlying disease process has significantly

improved or resolved (treatment of meningitis will not be discussed).

The approach is a multi-step process.

• Assess - Acute presentation (neurological manifestations such as coma, encephalopathy, seizures).

If symptomatic presentation - increase the serum sodium concentration / serum osmolality.

• Increase the serum sodium by 10 mEq/L or the serum osmolality by 20 mOsm/kg (10 mOsm from sodium and 10 mOsm from chloride) with the use of hypertonic or 3% saline (513 mEq/L of sodium or ~ 0.5 mEq/mL).

• Regardless of the approach, when the symptoms are improved the 3% infusion should be discontinued.

March 17, 2005

For sodium correction = 10 mEq/kg Na x body weight (BW) x 0.6 (distribution factor for sodium) = 6 BW = # of mEq to be infused.

Since there is 0.5 mEq Na/mL or 1 mEq per 2 mL, the amount of 3% saline to be infused over about 60-90 minutes would be 2mL/mEq

x 6 mEq X BW = 12 BW.

If the symptoms are absent or mild – asymptomatic presentation, lower infusion rate of 0.5 to 2 mL per kg of body weight may be used which

will increase the serum sodium from 0.5-2 mEq/L per hour. Some select isotonic saline in asymptomatic patients for patients with a serum sodium

above 123-125 mEq/L. IN EITHER CASE, the serum sodium should be monitored every 2-3

hours to prevent overcorrection of the serum sodium concentration.

The maximum serum Na correction per 24 hours should not exceed 10 mEq/L (some clinicians limit the increase to 8 mEq/L per 24 hours).

March 17, 2005

Case 3A six month-old infant presents to her pediatrician in December with a four day history of fever (up to 40oC), along with mild upper respiratory symptoms. On the evening and night prior to presentation she began

to have diarrhea and emesis with cessation of formula and solid foods The child had a wet diaper this morning.

On exam the child appeared quiet but became irritable during the exam, mucous membranes were mildly dry, and the skin felt doughy.

Vitals signs were the following: Blood pressure 85/58 mmHg; Temperature of 39oC, respiratory rate 40 and pulse 175. Weight 7.5 kg.

A previous weight about two weeks ago was 8.4 kg. There were no other significant findings and the child appears to have good turgor

and skin elasticity.

March 17, 2005

Question 3: What is the percent of dehydration?

A. 3-5%

B. 6-9%

C. 0%

D. 10%

E. 15%

March 17, 2005

With the magnitude of dehydration, high fever and irritability, the decision by the clinician was to initiate parenteral fluid replacement rather than oral rehydration therapy. The child was admitted to the hospital with

diagnosis of dehydration.

On admission the laboratory studies were as follows: Sodium 162 mEq/L , chloride 126 mEq/L, potassium 4 mEq/L

Bicarbonate (or total CO2) was 12 mEq/L Serum creatinine 1 mg/dL, blood urea nitrogen 29 mg/dL, blood glucose 85 mg/dL; complete blood count

was normal

Urinalysis/ chemistries: specific gravity of 1.030, no blood, protein or glucose, small ketones; urine creatinine 30 mg/dL and sodium 30 mEq/L;

Fractional excretion of sodium (FENa)( [urine sodium x serum creatinine]/ [serum sodium x urine creatinine]

x 100%) = ([30 mEq/L x 1 mg/dL] / [161 mEq/L x 30 mg/dL]) = 0.62%

Normal values for FENa = ~ 1-2%; decreased renal perfusion (dehydration, decreased intravascular volume) < 1%

March 17, 2005

In many cases there is extrarenal losses from diarrhea and vomiting with predisposing factors being young age, fever, curtailment of oral intake and possibly, high solute fluids such as concentrated or improper preparation of formula or other fluid with a high sodium content.

Child lost proportionally more water than sodium or a relatively hypotonic fluid loss. The result is higher extracellular fluid osmolality which results in a fluid shift from the ICF to ECF. This provides for better organ perfusion compared to iso- or hyponatremic dehydration of comparable degrees.

The child on exam appears better perfused and provides a history of urine output rather than oliguria. This may lead to an underestimate of the degree of dehydration. In this case the magnitude of the dehydration is about 10% or moderate.

The pre-illness weight was ~ 8.3 kg with a current weight of 7.5 kg or a 0.8 kg loss over last week.

Information suggest hypernatremic dehydration.

March 17, 2005

The decision by the clinician was to initiate parenteral fluid replacement rather than oral rehydration therapy.

The relative contraindications for oral rehydration therapy would include a young infant less than 3-4 months of age, the presence of impending shock or markedly impaired perfusion (increased capillary refill – turgor), inability to consume oral fluids due to intractable vomiting, marked irritability or lethargy/ unresponsiveness or the judgment of the clinician.

March 17, 2005

35 Na 64 K

31 Na

62 K2 Na

37 Na62 K2 Na

280

0

280

0

280

0

318

0

0.25 Liters 0.40 Liters

0.15 Liters

0.40 Liters

0.195 Liters 0.355 Liters

NORMAL

AFTER LOSS

AFTER OSMOTIC ADJUSTMENT

NORMAL ECF NORMAL ICF

mOsm/L

80

0

Loss0.10 LIters

2 K2 Na

413

0

318

0

March 17, 2005

Therapy Traditionally, treatment has been divided into three phases.

However in hypernatremic dehydration, the hyperosmolality results in the formation of idiogenic osmols (organic and inorganic) such as taurine, glutamate, glutamine, urea, inositol within the brain cells to assist in maintaining osmotic equilibrium between the two fluid compartments.

If the adjustment in osmolality (lowering) occurs to quickly in the extracellular compartment , the osmotic changes will result in the brain cells to swell with resultant neurologic manifestations such as hemorrhage.

March 17, 2005

Emergency / acute phase

This may need to be prolonged in cases of more significant volume depletion:

In some cases of hypernatremic dehydration emergent phase not necessary. If there are significant findings of decreased perfusion or hypotension, then therapy would be reasonable.

Otherwise the process is for a slow restoration of the serum sodium concentration to allow the idiogenic osmols to dissipate over a few days.

Similar to other forms of dehydration, if it is necessary to reestablish circulatory volume to prevent prolonged loss of perfusion to the key organs;

the fluid choices would be isotonic (0.9%) saline (normal saline) or another isotonic /hypertonic solution

March 17, 2005

Acute – Repletion/ Replacement /Restoration Phase Over 48 hours;

daily fluid/electrolyte maintenance requirements and deficit calculation are derived from standard estimates.

For hypernatremic dehydration there are two basic rules –

slow correction and close monitoring.

1. serum sodium concentration should not be reduced by more than about 10 mEq per day. Correct the patient over 48 hours for a serum

sodium concentration of less than 165 mEq/L; correct the patient over 72 hours for values above 165 mEq/L

2. Maintenance fluid / electrolyte calculations for 24 hours: Since the patient has a serum sodium concentration of 161, the correction is over 2

days so 2 days of maintenance fluids needs to added to the total fluid requirements for 48 hours.

March 17, 2005

1. Total 48 hours RequirementsThe total amount of maintenance (2 days) and deficit amounts are given equally over the 48 hour period with frequent monitoring of electrolytes in order to adjust the intravenous rate or sodium concentration based on the rate of decline of the serum sodium concentration.

Component of Therapy

Water Sodium Potassium Hourly RateRound number up or down to the nearest 5 increment

Maintenance – 2 days

1660 50 34

Deficit 800 33 17

Ongoing losses of diarrhea of vomiting*

TOTAL 2460 83 51 50 mL / hr

March 17, 2005

Fluid selection – 5% dextrose + ¼ isotonic saline (~30-40 mEq/L of Na) + 20 mEq KCl /L

Generally the final solution potassium concentration is about 20 mEq/L, it should not exceed 40 mEq/L without

close intensive care monitoring. The 5% dextrose provides 50 grams of carbohydrate per liter of 50 grams

x ~ 4 calories per gram = 200 calories. This would be about 20% of the daily caloric intake which is sufficient to prevent protein breakdown over a short treatment

period (less than one week).

March 17, 2005

Case 4

A 4 year old was referred for evaluation for short stature. The primary care physician has followed the patient since birth. The child is below the 5th % ile for height and the 10th %ile for weight. The child has a normal physical examination and no prior illnesses or hospitalizations.

Initial studies show a urine pH of 6.7, negative for glucose, ketones, blood and protein. No crystals, bacteria or casts.Serum values: Na – 140 mEq/L, K - 4 mEq/L, Cl – 110 mEq/L, Bicarbonate 17 mEq/L, glucose 80

March 17, 2005

Case 3: The most likely diagnosis with this presentation is

A. Fanconi’s syndrome

B. Chronic kidney failure

C. Renal tubular acidosis

D. Bartter’s syndrome

E. Gitelman’s syndrome

March 17, 2005

Serum Anion Gap

• Anion gap (AG, mEq/L) = (Na+)– (Cl- + HCO3-)

• Normal is 8 to 16

March 17, 2005

Causes of Metabolic Acidosis by type of Anion Gap

Normal Anion Gap (Hyperchloremic) Elevated Anion Gap

Renal (loss of bicarbonate)Renal Tubular Acidosis – Type 1 (Distal) -, 2 (Proximal) and 4 (mineralcorticoid) – See table 5 below)Renal Failure (Early)Carbonic Anhydrase Inhibitors – AcetazolamidePotassium sparing diureticsMineralocorticoid deficiency

Renal Failure – acute and chronic

Gastrointestinal (loss of bicarbonate)Diarrhea, Drainage (small bowel, pancreatic, biliary, fistula, etc), anion exchange resins

Poisoning - carbon monoxide or cyanide Circulatory Failure / Tissue Hypoxia

MiscellaneousRapid intravenous expansion with bicarbonate or isotonic/hypertonic solutionsRecovery from KetoacidosisPost-hypocapniaExogenous chloride administration (CaCl2, MgCl2, Arginine HCl, HCl) Hyperalimentation

Lactic Acidosis – hypoxia, glycogen storage disease (type 1), pancreatitis, leukemia, seizuresKetoacidosis – diabetes mellitus, starvationIngestions or overdose – Ethanol, methanol, ethylene glycol, salicylate, isoniazidInborn errors in metabolism, organic acidosisParaldehyde – organic anions

March 17, 2005

Electrolyte disturbances: RTA

• Metabolic acidosis– Normal anion gap -- hyperchloremic

• Diarrhea• RTA

– High anion gap -- normochloremic• MUDPIES or KUSSMAUL• Key entities:

– DKA– Lactic acidosis– Uremia– Metabolic disease– Toxins

March 17, 2005

Evaluation of Metabolic AcidosisClassification and Diagnosis of Metabolic Acidosis

Measure serum anion gap

HIGH

Calculate osmolal gap

HIGH NORMAL

Ethylene glycolMethanol Alcoholic ketoacidosis

Diabetic ketoacidosisD-lactic acidosis

Lactic anion acidosisMethylmalonic acidosisPyroglutamic acidosis

SalicylatesStarvation ketoacidosis

NORMAL

Calculate urine anion gap

Cl > Na + K Cl < Na + K

Proximal Renal Tubular Acidosis

(type II)Acetazolamide administration

Intestinal HCO3-

losses (diarrhea)Exogenous acid administration

Total parenteral nutrition

Ureterosigmoidostomy

Rectouretheral fistula

Urine pH

> 5.8 < 5.8

Serum K RTA (type IV)

HighLow

Distal RTA (type I)

Hyperkalemic Distal RTA

March 17, 2005

Patient

• Repeat urine pH showed a pH of 6.5, venous blood gas had a pH of 7.28, bicarbonate of 15 mEq/L, Pco2 was 34, serum creatinine was 0.4 mEq/L, BUN of 6, urine calcium to creatinine ratio was 1.1 (increased)

March 17, 2005

Features of Renal Tubular Acidosis in Childhood

FeaturesType I(Distal)

Type II(Proximal)

Type IV(Hyperkalemic)

Urine pH during acidosis >5.5 <5.5 <5.5

Urine anion gap Positive Negative Positive

FEHCO3- at normal serum HCO3 <15%* >15% <15%

Serum potassium Normal or low Normal or low Increased

Calcium excretion Increased Normal or ↑ Normal (?)

Nephrocalcinosis Common Rare Absent

Associated tubular defects Rare Common Rare

Rickets Rare Common Absent

Daily alkali requirement (mEq/kg/day)

1-4* 10-15 2-3

Potassium supplementation No Yes No

March 17, 2005

Electrolyte disorders: Fanconi’s

March 17, 2005

Electrolyte disorders: metabolic alkalosis

• Extrarenal/GI loss of K– CF

• Vomiting– NG suction– Pyloric stenosis

• Distal GI loss of bicarbonate– Chloride diarrhea

• Renal– Bartter’s– Gitelman’s– Apparent mineralocorticoid excess (AME)/licorice

March 17, 2005

Electrolytes: Pearls

There are three pure renal causes of FTT – azotemia, DI, and RTA

RTA causes hyperchloremic acidosis

Bartter’s and Gitelman’s differ in calcium excretion – high in former low in latter

March 17, 2005

RENAL

March 17, 2005Trying to think about pediatric kidney disease - nephWHAT

March 17, 2005

Hematuria

Case 5: Susan is an 8 year old noted on routine exam to have moderate hematuria on dipstick. She has an unremarkable past medical history. Family history is negative in the parents and siblings for any renal disease. History of hematuria is unknown. A repeat urine in one week is still positive and a urine culture showed no growth.

March 17, 2005

Question 5: Which of the following test is the next step in the evaluation?

A. VCUG and urine culture

B. Renal sonogram and urine calcium to creatinine ratio

C. Urology referral

D. CBC and Direct Coombs

E. Recheck in one year

March 17, 2005

• Repeat a first AM void following restricted activity , perform a microscopic on a fresh urine

• Check the family members• If there is still blood without protein, casts,

crystals, normal BP with or without a strong family history, no further work-up is generally required. However a renal sonogram and urine calcium to creatinine ratio

• Caveat - Family anxiety because of the connotation of blood and cancer in adults.

March 17, 2005

Classification of Hematuria

• Microscopic (vast majority of the cases)– Transient– Persistent

• Macroscopic (urologic / renal disorders)– Transient– Persistent (> 2 weeks)

• Persistent microscopic/ Transient macroscopic– IgA or Berger’s; benign recurrent hematuria

March 17, 2005

Glomerular v. Non-glomerular bleeding

• Glomerular

– oliguria, edema, hypertension, proteinuria, anemia

• Non-glomerular

– dysuria, frequency, polyuria, pain or colic, hx

exercise

– crystals on microscopic

– mass on exam

– medication history - sulfas, aspirin, diuretics

March 17, 2005

Who should be worked up?

• Presence of proteinuria and/or hypertension

• History consistent with infectious history, HSP, systemic symptoms, medication use or abuse, strong family history of stones or renal disease/failure.

• Persistent gross hematuria• Family anxiety - limit evaluation

March 17, 2005

Initial evaluation of the patient with hematuria

• All patients: Serum creatinine, kidney and bladder ultrasound, urine calcium to creatinine ratio

• Probable glomerular hematuria – C3, ASO titer– possible: hepatitis, HIV, SLE serology , SSD– renal biopsy – not for persistent microscopic without proteinuria,

decreased renal function, and/or hypertension• Probable non-glomeurlar hematuria

– urine culture, urine Ca/creatinine ratio– possible: hemoglobin electrophoresis,– coagulation studies, isotope scans,– Flat plate, CT, ??IVP, cystoscopy

March 17, 2005

Pearls for Hematuria

• Hematuria is an important sign of renal or bladder disease

• Proteinuria (as we will discuss) is the more important diagnostic and prognostic finding.

• Hematuria almost never is a cause of anemia• The vast majority of children with isolated

microscopic hematuria do not have a treatable or serious cause for the hematuria, and do not require an extensive evaluation. So a VCUG, cysto and biopsy are not indicated.

March 17, 2005

More Pearls

• Urethrorrhagia – boys with bloody spots in the underwear– Presentation – prepuberal ~ 10 yrs– It is painless– Almost 50% will resolve in 6 months and > 90% at 1

year; it may persist for 2 yrs– Treatment – watchful waiting in most cases

• Painful gross hematuria – usually infection, calculi, or urological problems; glomerular causes of hematuria are painless.

March 17, 2005

More Pearls – gross hematuria

• Gross hematuria is often a presentation of Wilms’ tumor

• All patients with gross hematuria require an imaging study.

• If a cause of gross hematuria is not evident by history, PE or preliminary studies, the differential is hypercalciuria, SS trait, or thin basement membrane disease.

• Cysto is rarely helpful

March 17, 2005

Case 6: 7 year old boy developed gross tea colored hematuria after a sore throat and upper respiratory infection. No urinary symptoms but urine output was decreased. He complained of mild diffuse lower abdominal pain. There is no fever, rash or joint complaints. Past med history was unremarkable but had intermittent headaches for two years.

On exam he was well (afebrile) with a BP of 95/65 mHg, no edema, some suprapubic tenderness and red tympanic membranes. The mother thinks that a similar episode occur on vacation a few months ago.

Urinalysis shows 20 RBCs/hpf, 5-10 WBCs, 100 mg/dL of protein, rare cellular and hyaline casts. Serum creatinine is 0.8 mg/dL, C3 100 (normal).

March 17, 2005

Question 6: The most likely cause of the gross hematuria is:

A. Myoglobinuria

B. Urinary tract infection

C. Obstructive uropathy

D. IgA nephropathy

E. Benign familial hematuria

March 17, 2005

IgA

• IGA nephropathy– Boys > girls– Mostly normotensive, with persistent

microscopic hematuria– Chronic glomerulonephrits – up to 40% of

primary glomerulonephritis– Complement studies are nl, some inc IgA – Prognosis – not so good if > 10 yrs of age,

proteinuria, reduced GFR, hypertension and no macrohematuria

March 17, 2005

Acute Glomerulonephritis

Low Complement Normal Complement

Systemic diseasesSLE

Subacute Bact EndocarditisShunt nephritis

Essential mixed cryoglobulinemiaVisceral abscess

Systemic diseasesPolyarteritis nodsa

Hypersensitivity vasculitisWegener’s

HSPGoodpasture’s

Renal diseasesAcute proliferative GN

Membranoproliferative GN

Renal diseasesIGA

RPGN -Anti-GBM, immune complex GN

Serologic evidence of antecedent strep infection(ASO, anti-Dnase B, streptozyme

PSAGNStrep endocarditis

LupusEssential mixed cryoglobulinemia

Shunt nephritisVisceral abscess

MPGNNon-strep infection

Clinical evidence to support endocarditis

Blood culturesEchocardiogram Treat PSAGN

Positive Negative

March 17, 2005

Glomerular Non-glomerular

Urinalysis Dysmorphic RBCCellular castsBrown/tea colorBright redClotsCrystalsProtein

++

+++--+

--+

++++-

History Family Hx of ESRDSystemic diseaseNephrolithiasisTraumaSymptomatic vomiting

++---

--+++

Physical HypertensionSystemic signsEdemaAbdominal massGenital bruising

++++--

+--++

March 17, 2005

Red or Tea colored/ Brown Urine

Fresh Centrifuged Urine Sample

Sediment Red withRed Cells

Supernatant Red withoutRed Cells

Hematuria

NOTE: If there is no red sediment, no RBCsand a clear supernatant, consider other causes such as urates, bile pigments,beets, porphyria, some medications, etc.

Hemoglobinuria*

Myoglobinuria

* Hemoglobinuria will havea red or pink hue to the serum

March 17, 2005

On routine physical examination, an 8-year-old boy is found to have microscopic hematuria. The first step in your evaluation should be.

A. Examine the urine sedimentB. Order an intravenous pyelogramC. Obtain a voiding cystourethrogramD. Perform a CBC in the officeE. Order an ASO titer

Question 7

March 17, 2005

An 8-year-old boy presents with tea colored urine. He has very mild edema. History of strep infection about 2 weeks ago. The work-up should include all the following except.

A. Complement studies

B. Serum creatinine

C. Urinalysis for protein

D. Monitor blood pressure and urine output

E. Obtain an intravenous pyelogram and VCUG

Question 8

March 17, 2005

Acute glomerulonephritis: clinical

• May be clinically asymptomatic (? 90%) with low C3 and hematuria

• Usually within 3 weeks after strep infection – mean about 10 days

• Periorbital, peripheral edema• Hematuria - coke-colored, tea-colored,

reddish/brown• Nonspecific findings such as abdominal

pain, malaise, anorexia, headaches, pallor

March 17, 2005

Acute glomerulonephritis: DD

• Acute Poststreptococcal glomerulonephritis (PSAGN) – most common

• Acute Postinfectious or nonstreptococcal postinfectious glomlerulonephritis 9AIAGN)– Bacterial: endocarditis (low C3), shunt nephritis (low

C3), pneumococcal pneumonia, etc.– Viral: hepatitis B, infectious mononucleosis, varicella,

etc,– Parasites:

• Other: SLE (low C3), membranoproliferative GN (low C3), hyperthyroidism, HSP (nl C3)

March 17, 2005

Acute glomerulonephritis: evaluation/ treatment

• Evaluation– ASO– C3, C4– Renal function– Evaluation for hypertension and oliguria– Magnitude of proteinuria

• RX – supportive – Admission for hypertension, oliguria, impaired renal

function, nephrotic syndrome• Prognosis: C3 normalizes by 12 weeks,

hypertension and other abnormalities resolve by 2-3 months, hematuria may persist for 6-24 mo

March 17, 2005

Please try to

Wait until the

Lecture is over

We are talking about the kidneys

March 17, 2005

Proteinuria

Case 9: John is an 12 year old noted on a basketball team physical to have 2+ protein on dipstick. There are no recent illnesses. He has an unremarkable past medical history and he is not taking any medications. Family history is negative in the parents and siblings for any renal disease.

March 17, 2005

Question 9: Which of the following is the best approach?

A. Obtain a 1st AM urine for protein

B. Perform a complete biochemical profile

C. Obtain a C3, ASO and ANA

D. Refer for a renal biopsy

E. Schedule a renal sonogram and VCUG

March 17, 2005

What does Orthostatic Proteinuria mean?

Normal Orthostatic Recumbant

Erect

Threshold of Detection

ProteinExcretion

March 17, 2005

• Repeat a first AM void following restricted activity, perform a microscopic on a fresh urine; also an alkaline pH may give a false positive result

• If there is still protein perform a more formal orthostatic test. If orthostatic, no further work-up is generally required, although no indemnification from subsequent renal disease.

• Caveat - Family anxiety because of the connotation of protein and friends told them about kidney failure.

March 17, 2005

Causes of Proteinuria

• Transient– fever, emotional stress, exercise, extreme cold,

abdominal surgery, CHF, infusion of epinephrine• Orthostatic

– Transient or fixed / reproducible• Persistent

– Glomerular disease: MCNS, FSGS, MPGN, MN– Systemic: SLE, HSP, SBE, Shunt infections– Interstitial: reflux nephropathy, AIN, hypoplasia,

hydronephrosis, PKD

March 17, 2005

A four-year boy presents with a 5-day history of swollen eyes and “larger ankles”. On exam he has periorbital and pretibial edema. The most appropriate tests include all the following except.

A. UrinalysisB. Blood tests for total protein and albuminC. Serum creatinineD. Sedimentation rateE. Serum complement (C3)

Question 10

March 17, 2005

Definitions (Pearl)

• Urine protein to creatinine ratio– Normal: < 0.2 (< 0.15 adolescents)– Mild to moderate: 0.2 to 1.0– Heavy or severe: > 1.0

• Persistent proteinuria: present both in the recumbent and the upright posture; even in this situation, proteinuira is less during recumbency

March 17, 2005

Nephrotic Syndrome• Primary Nephrotic Syndrome:

– Minimal change disease (~75%) – mean age 4 yrs• No hematuria, nl C3, no hypertension, nl creatinine

– Membranoproliferative GN (~ 5-10%)– FSGS (5-10%)– Proliferative GN, Mesangial proliferation – Membranous nephropathy

• Secondary Nephrotic Syndrome: – SLE, HSP, diabetes mellitus, HIV, vasculitis, malignancy (lymphoma,

leukemia), drugs (heroin, inteferon, lithium), infections (toxo, CMV, syphilis, hepatitis B and C)etc.

• Congenital/Infantile Nephrotic Syndrome:– Finnish-type congenital nephrotic syndrome,Denys-Drash syndrome– Diffuse mesangial sclerosis, Nail-patella syndrome

March 17, 2005

Nephrotic Syndrome - RXCorticosteroid treatment • Induction therapy:

– Exclude active infection or other contraindications prior to steroid therapy. – Oral prednisone or prednisolone at 60 mg/m2/d (~2 mg/kg/d) daily for 4 weeks.

• Maintenance therapy (following above induction therapy) – Oral prednisone or prednisolone at 40 mg/m2 (or ~1.5 mg/kg) given as a single dose

on alternate days for 4 weeks. – NOTE: Some nephrologists recommend daily induction steroid treatment for 6 weeks,

followed by alternate day maintenance therapy for another 6 weeks. • Relapse therapy

– For infrequent relapses, Prednisone 60 mg/m2/d (~2 mg/kg/d) given as a single morning dose until proteinuria has resolved for at least 3days.

– Following remission of proteinuria, prednisone is reduced to 40 mg/m2 (or ~1.5 mg/kg) given as a single dose on alternate days for 4 weeks. Prednisone may then be discontinued or a tapering regimen.

Frequently relapsing nephrotic syndrome is defined as steroid-sensitive nephrotic syndrome with 2 or more relapses within 6 months or more than 3 relapses within a 12-month period.

March 17, 2005

Hypertension

March 17, 2005

Hypertension

Case 11: David is a 10 year old boy first noted to have an elevated blood pressure of 123/85 during a annual physical examination. Pt has a long history of learning and behavioral issues. He has a previous history of headaches that were evaluated with a CT scan of the brain and sinuses. On following evaluation in one week, his BP is126/86 mmHg with a weight > 99%ile for age and a height at ~50th %ile.

March 17, 2005

Question 11: What is the most appropriate initial testing for this child?

A. Renal mag-3 flow scan

B. Electrolytes, BUN, Creatinine, Bicarbonate

C. Renal Sonogram with doppler

D. Urinary screening for drugs

E. 24 hour urine for catecholamines

March 17, 2005

BP ClassificationGrade of hypertension Definition Appropriate next step

“White-coat” hypertension BP levels >95th percentile in a physician's office or clinic, but normotensive outside a clinical setting

Readings may be obtained at home with appropriate family training or with the assistance of a school nurse, or with the use of ambulatory BP monitoring (ABPM)

Normal < 90th %ile

Pre-hypertension >120/80 mm Hg should be considered pre-hypertensive or90-95%ile

Additional readings may be obtained at home with appropriate family training or with the assistance of a school nurse

Stage I hypertension 95th -99th %ile + 5 mmHg Organize a diagnostic evaluation in a non-urgent, phased approach

Stage II hypertension Average SBP or DBP that is >5 mm Hg higher than the 99th percentile

Organize a diagnostic evaluation over a short period of time in conjunction with pharmacological treatment

Hypertensive urgency and emergency

Average SBP or DBP that is >5 mm Hg higher than the 95th percentile, along with clinical signs or symptoms

Hospitalization and treatment to lower the blood pressure

March 17, 2005

Estimate of Hypertension

Estimate without height adjustment1. If systolic BP equals or exceeds

100 + 2 times pt age in yrs

2. If diastolic BP equals or exceeds 70 + pt age in yrs

Estimate with height adjustment3. If systolic BP at 95th %tile for age and sex

Add 4 mmHg to the value at the 50th %tile

2. If diastolic BP at 95th %tile for heightAdd 2 mmHg to the value at the 50th %tile

March 17, 2005

Historical Information

Physical Examination

Neonatal historyFamily historyDietary history

Risk Factors (smoking, alcohol use, drug use)

Non-specific / specific symtomatologyReview of Systems - sleep and exercise

patterns, etc.

Vital signs(including extremities)

Height/WeightSpecific attention to organ systems -

cardiac, eye, abdominal or other bruits, etc.

Consider ambulatory blood pressure monitor

Evaluation Phase 1

CBC, urinalysis, urine culture, electrolytes, BUN, creatinine, thyroid studies, uric acid

plasma renin, lipid profile, echocardiogram, renal ultrasound with duplex doppler

Evaluation Phase 2 Selected studies based on magnitude of the hypertension and/

or other clinical /laboratory findings

Renal flow scan (MAG 3)CT Angiography (CTA)

MRA (may not provide adequate evaluation for peripheral renal vascular lesions)

Renal arteriography with renal vein samplingPlasma / urine catecholamines and/or steroid concentrations

Evaluation of Hypertension

March 17, 2005

Indications for Treatment

• Symptomatic hypertension• Secondary hypertension• Hypertensive target-organ damage• Diabetes (types 1 and 2)• Persistent hypertension despite

nonpharmacologic measures

March 17, 2005

Pharmacologic Therapy for Childhood Hypertension

• The goal for antihypertensive treatment in children should be reduction of BP to <95th percentile, unless concurrent conditions are present. In that case, BP should be lowered to <90th percentile.

• Severe, symptomatic hypertension should be treated with intravenous antihypertensive drugs.

March 17, 2005

Urinary Tract Infections

100Feld - 10/98

Case History

• A 4 mo old girl presents with low grade fever, mid-lower abdominal pain and nighttime-incontinence. She is not eating well. Prior visits she had normal blood pressure, urinalysis and excellent growth. dUrinalysis shows hematuria, 30 mg/dL of protein, leukocyte esterase and positive nitrite. Urine culture is obtained.

March 17, 2005

Question 12: What is the most likely bacterial cause of her urinary tract infection?

A. Proteus mirabilis

B. E. coli

C. Coagulase negative Staphlococus

D. Alpha hemolytic Streptococcus

E. Klebsiella pneumoniae

102Feld - 10/98

Bacteriology /Pathogenesis UTI - 1

• Most Common - E. Coli, coliforms

• Virulence Factors • adherence to uroepithelium by P-fimbriae

• endotoxin release

• Pyelo vs cystitis - 80 to 20%

103Feld - 10/98

Bacteriology /Pathogenesis UTI 2

• Perineal / urethral factors– uncircumcised - 10-20x risk– ? Urethral caliber (infant girls)– other myths such as bubble bath, wiping

techniques• Low Urinary factors

– dysfunctional voiding ; constipation• Other - indwelling catheters, congenital

anomalies, Vesicoureteral reflux, sexual activity

104Feld - 10/98

Diagnosis

• Leukocyte test and nitrate test

• Urine culture > 40-50,000 CFU/mL

• Pyuria - not on recurrent UTIs

105Feld - 10/98

Clinical Issues

• Lower tract - frequency, urgency,

enuresis, dysuria

• Upper tract - fever - nearly all in boys

under 1 year of age; females peak in

first year but still significant through the

first decade

• Asymptomatic bacteriuria - low risk

106Feld - 10/98

Radiological Evaluation

• Renal ultrasound - anatomy, size, location, echogenicity

• DMSA (2nd choice glucoheptanate - SGH) - cortical integrity, photopenic regions, differential function, abscess

• CT scan - abscess• VCUG - standard for first UTI; radionuclide

for follow-up or siblings• IVP - NO WAY

107Feld - 10/98

Grades of Reflux

108Feld - 10/98

Reflux Recommendations“the simple way”

• GRADES I - III Antibiotics

• GRADES IV - V Surgery

109Feld - 10/98

Treatment

• Oral– SMX-TMP, Amoxicillin/Clavulanate– Cefuroxime, cefprozil, cefixime, cefprodoxime

• Parenteral– Neoates: Ampicillin / Gentamicin– Older Children:

• Advanced level cephalosporin• Beta lactam + beta lactamase inhibitor• Aminoglycoside (+ ampicillin)

110Feld - 10/98

Question 13: Case History

• A 12 mo old girl is diagnosed with the first febrile UTI. She is not eating well. UA shows pyuria and bacteria. Urine culture is obtained and shows > 100,000 colonies of E. Coli. Antibiotics are given.

March 17, 2005

Question 13: What is the most appropriate next step?

A. Perform a DMSA renal scan

B. Refer to urology for cystoscopy

C. Perform a renal sonogram and VCUG

D. Perform urodynamics and flow studies

E. Repeat urine culture in 3 months

112Feld - 10/98

The Suggested Answers

• What are your concerns?– Voiding history

• Radiographic studies– ultrasound and VCUG

• Follow-up (no reflux)– cultures every month for three months,

then every other month for six months

( every 4 months)• Follow-up (reflux) - antibiotics

March 17, 2005

Glomerulonephritis / Acute renal failure

114Feld - 10/98

Case History

• A 3 year old boy was attending summer camp. Five days later he presents with diarrhea, abdominal pain and appear pale. His mother finds out that there was cook out at camp. On examination the child is pale and is unable to void. His laboratory testing in your office shows a WBC of 26,000, hemoglobin of 8 g/dL, platelets 98,000, Serum creatinine of 1 mg/dL, BUN 54 mg/dL, urinalysis with large blood, 100 mg/dL of protein.

March 17, 2005

Question 14: What is the most likely diagnosis?

A. Henoch Schoenlein Purpura

B. Post streptococcal glomerulonephritis

C. IgA nephropathy

D. Acute pyelonephritis

E. Hemolytic uremic syndrome

Clinical prodrome

• Diarrhea prodrome 1-15 days• Abdominal pain – may be confused with

ulcerative colitis, appendicitis, rectal prolapse, intussusception

• Pallor• Irritability, restlessnes• Edema – after rehydration• Oliguria/anuria

HUS: Clinical manifestations

• Thrombocytopenia• Hemolytic anemia• Renal failure• Neurologic (irritability, seizure, CVA)• Pancreatitis (IDDM) and colitis• Hypertension

March 17, 2005

HUS: Pathogenesis

• Endothelial cell damage occurs secondary to toxin injury via binding to glycolipid receptor or lipopolysaccharide absorption.

HUS: Differential diagnosis

• Other forms of acute Glomerulonephritis / renal failure

• Vasculitis• Urosepsis• Renal vein thrombosis• Coagulopathy (DIC)

Conservative management

• Fluid restriction to <insensible losses plus urine output

• Foley catheter – limit to 24-48 hrs• Blood transfusion / platelets• Routine use of antibiotics controversial• Diuretics• Nutrition

Surgical Complications

• Toxic megacolon• Rectal prolapse• Colonic gangrene• Intussusceptions• Perforation• Strictures• Mimic appendicitis, IBD

March 17, 2005

March 17, 2005

Thank you

GOOD LUCK

March 17, 2005

Supplement 1

• Acute renal failure• Chronic renal failure• More Fluids & Electrolytes• Tubular disorders• Cystic kidney disease

March 17, 2005

Acute Renal Failure (ARF) vs Pre-renal Azotemia

• Key maneuver is restore RBF to distinguish reversible pre-renal state from short-term irreversible

• Options– Bolus infusion of crystalloid solutions– Infusion of albumin– Administration of pressors– Administration of antagonists of clinical

condition as in anaphylaxis

March 17, 2005

ARF: Diagnosis

Pre-renal AGN ATN Obstruction

UA Marginal value

KeyRBC casts

RTEC Marginal value

SG >1.020 >1.020 1.008-1.012

1.008-1.012

UNa <20 <20 >40 >40

FENA <1% <1% >1% >1%

Uosm >400 >400 200-400 200-400

March 17, 2005

ARF: Diagnosis

• AGN– PSAGN– HSP– SLE– MPGN– Wegener’s

March 17, 2005

ARF: Diagnosis

• ATN– Unreversed pre-renal azotemia– Nephrotoxic meds– Contrast agents– High calcium, uric acid, phosphate– Rhabdomyolysis (myoglobin)– Intravascular hemolysis (hemoglobin)

March 17, 2005

ARF: Diagnosis

• Obstructive uropathy– PUV– Prune belly– Vesicoureteric reflux– Neurogenic bladder (myelomeningocele)– Megacystis/megaureter– Secondary: stones, fibrosis

• Effect of age and gender

March 17, 2005

ARF: Testing

• Key labs: BUN, creatinine, K• EKG• CXRay• Renal ultrasound• Specific blood tests based on underlying

condition

March 17, 2005

ARF: Management

• Urgent issues– Potassium

• Calcium• Glucose/insulin• NOT bicarbonate

– Blood pressure: parenteral therapy• Labetalol• Nitroprusside

– ECF volume

March 17, 2005

ARF: Conservative Management

• Potassium– Diet restriction– Kayexalate

• Blood pressure– IV/PO meds

• ECF volume– Na restriction– Diuretic use – need for furosemide

March 17, 2005

ARF: Pearls

• Pre-renal azotemia and AGN are similar• ATN and post-renal failure are similar• Potassium kills first in ARF

March 17, 2005

CKD: Diagnosis

• Stages– CKD I: renal injury GFR >90– CKD II: GFR 60-90– CKD III: GFR 30-60– CKD IV:GFR 15-30– CKD V: ESRD

March 17, 2005

CKD: Common features

• Impact on growth• Impact on bone: osteodystrophy• Impact on puberty• Impact on development – social and

cognitive

March 17, 2005

CKD: Causes

• Non-glomerular– Hypoplasia/dysplasia– Reflux nephropathy– Obstructive uropathy

• PUV• Prune Belly• Neurogenic bladder

March 17, 2005

CKD: Clinical manifestations

• Growth failure– Dependent on age of onset– Dependent on level of GFR

• UTIs– Pyelonephritis

• Electrolyte abnormalities– Pseudohypoaldosteronism– Nephrogenic DI

• Neurocognitive disability

March 17, 2005

CKD: Causes

• Glomerular– FSGS– HUS– SLE– Membranoproliferative MPGN)– Alport– IgA Nephropathy– Membranous nephropathy– NOT diabetic or hypertensive nephropathy

March 17, 2005

CKD: Clinical manifestations

• Growth failure– Dependent on age of onset

• Hypertension– Role of ECF volume and PRA

• Electrolyte abnormalities– Acute– Hyperkalemia

• Edema• Signs of underlying disease

March 17, 2005

CKD: Diagnosis

• Low value of radiology tests• Blood tests

– C3, C4, CH50– ASLO– ANA, dsDNA, Ro, La, Sm– ANCA– Anti-GBM– Renal biopsy

March 17, 2005

CRF: Management

• Nutritional supplementations– CHO deficiency

• Protein restriction– Impact on growth– Effect in more advanced CKD

• BP control– Disease progression– ACEI/ARB

March 17, 2005

CRF: Management

• Interference with renin-angiotensin aldosterone axis– Safety of ACEI even with advanced CKD– Role of combined ACEI/ARB– Effect of aldosterone antagonists

• Safety issues– Hyperkalemia– Reduction in GFR

March 17, 2005

CRF: Management

• Endocrine treatments– rhGH

• Doubles growth velocity• Minimal risk of progression

– Erythropoietin• Nearly always effective• Antibody induced pure red cell aplasia

– Calcitriol• IV route• More selective agents

March 17, 2005

CRF: Pearls

• Chronic glomerular diseases have oliguria vs chronic tubular diseases which can have polyuria and sodium loss– Nocturia and enuresis may indicate CRF

• Severity of growth failure and neurocognitive deficits are inversely related to age of onset of CRF

March 17, 2005

CRF: More pearls

• Most important feature of nutritional support is to correct low caloric intake

• Medication doses need to be adjusted as GFR declines

• Almost no form of CRF is a contraindication to transplant