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PATOLOGI KIMIA Head of Unit : Dr Nur Shafini Binti Che Rahim
Phone
: +60326155555 ext 5284
1. INTRODUCTION
Chemical Pathology unit provides diagnostic and consultative services to Hospital Kuala
Lumpur and also serves as referral center for hospitals and clinics in Malaysia. Our
services cover analysis and interpretation of results for screening, diagnostics and
monitoring of diseases.
Chemical Pathology Unit offers specialized biochemical testing. The list of services
include:
i. Endocrine
Thyroid Function Test, Fertility Test, Serum and Urinary Cortisol, Urine
Catecholamine, Extended Hormone (Dehydroepiandrosterone sulphate (DHEAS),
Insulin, C-peptide, Growth Hormone, Adrenocorticotrophic Hormone (ACTH)) and
Parathyroid Hormone (PTH), Thyroglobulin, Anti-thyroglobulin, Anti-thyroid specific
peroxidase and Anti-thyroid stimulating hormone receptor.
ii. Metabolic
HbA1c, Gamma Glutamyl transferase (GGT) and Cholinesterase (CHE)
iii. Protein and Proteomic
Serum and Urine Protein Electrophoresis, Specific Protein (Ceruloplasmin,
Immunoglobulin IgG, Immunoglobulin IgA, Immunoglobulin IgM, Transferrin,
Haptoglobin, Alpha -1-antitrypsin)
iv. Hematological Biochemistry
Iron,UIBC, Ferritin,Folate, Vitamin B12
2. SERVICES
Operating hours: 7.30 am – 5.30 pm (Monday to Friday)
URGENT request: Arrangement should be made by contacting Pathologist, Medical
Officer or Scientific Officer in-charge.
All specimens must be accompany with PER.PAT 301 form. Forms must be filled
LEGIBLY and COMPLETELY with the following information:
Patient`s details: Name, IC number, sex, age and ward/hospital name
Patient`s clinical and test details: relevant clinical history, diagnosis, test
required, type of sample, time and date of sample collection.
Requesting doctors details: name, stamp and signature.
5.1 BLOOD
Most of tests in Chemical Pathology require serum sample that need to be collected in
plain tube. Special requirements are require for certain tests:
HbA1c: require whole blood sample that need to be collected in EDTA tube.
Request less than 3 months from previous result will be rejected.
Morning serum cortisol: between 8 to 10 am; midnight serum cortisol: between
10 to 12 pm.
Fertility tests: Sample for progesterone should be collected at day 21 of
menstrual cycle, while sample for estradiol, FSH and LH should be collected at
day 2 to 5 of menstrual cycle.
Certain tests require to be sending in ice such as ACTH.
3. SERVICE HOURS
4. REQUEST FORMS
5. SAMPLE COLLECTION
Serum and Urine Protein Electrophoresis should be send as paired sample for
better interpretation of test results
5.2 URINE
24 hours Urine Collection
24 hours urine collection require due to certain test which effected by circadian
rhythmic changes.
Procedure of collection:
On the day of collection, the first urine voided must be thrown away. Time of first
urine voided is the start of the timing for the 24 hours collection.
Collect the second and subsequent voided urine for 24 hours into the 24 hours
urine container until completed.
For male patient, it is advisable NOT to void the urine directly into the 24 hours
urine container. This is to avoid possible chemical burns.
Refrigerate urine sample if possible.
Label the bottle as directed and send immediately to the laboratory.
eg. Tests include 24-hours urine cortisol and 24-hours urine catecholamines.
24-hours Urine Catecholamine
Please refer to procedure 24 hours urine collection to collect urine for 24 hours
urine catecholamines.
For adult minimum 750ml of urine should be collected. For paediatric samples
urine creatinine are perform for every request.
Please note that, 10ml of 6M HCl (preservative) is added into the bottle to
preserve the analytes. It is important for the requesting physician to advise the
patient NOT to discard the preservative.
Instruction on patient preparation and specimen collection
o Certain drugs or their metabolites are a source of possible interference with
catecholamines quantification. List of drugs that may interference with
catecholamines quantification:
a) Acetaminophen (paracetamol)
b) Cimetidine (Tagamet®)
c) Alpha-methyldopa (Aldomet®)
d) Isoproterenol
e) Labetalol
f) Mandelamine
g) Metoclopramide
o Please advise patient to avoid stress, exercise, smoking and pain prior to
and during urine collection.
24-hours Urine Cortisol
Please refer to procedure 24 hours urine collection to collect urine for 24 hours
urine cortisol.
Minimum of 500 ml of urine should be collected.
Specimens are receive at the main counter (Kaunter Penerimaan Utama Unit Makmal Teras).
Results are validated by Chemical Pathologist/Medical Officer/Scientific Officer
according to the test following laboratory turnaround time.
Reference ranges are provided for all results. These may be subject to variation
differentiated by age and sex where important / available.
Reports are dispatched to the respective pigeon hole or posted via mail for external
samples.
6. RECEIPT OF SPECIMEN
7. REPORTING OF RESULTS
Enquiry of test results can be made using:
1) Form for tracing laboratory results i.e Borang Mendapatkan Keputusan Ujian
Patologi, HKL/JP/PA/AK-05-01 at Kaunter Penerimaan Utama Unit Makmal Teras in
Pathology Department.
2) Labviewer in respective ward or clinic
3) Phone extension 5284,
For external clients tracing can be made via official letters to:
Head of Department,
Pathology Department,
Jalan Pahang,
50586 Hospital Kuala Lumpur.
If test needed after working hours, consultation and agreement from Chemical
Pathologist on-call are required.
The protocols listed below are only as guide and are subjected to changes according to
clinician requirement. These protocols are mainly for adult.
10.1 PITUITARY DISORDERS
Assessment of Anterior pituitary Hormone
1. Pituitary Hormone Insufficiency
Anterior pituitary hormones include Growth Hormone (GH), Prolactin, Thyroid
Stimulating Hormone (TSH), Follicle Stimulating Hormone (FSH), Luteinizing Hormone
8. ENQUIRY OF RESULTS
9. SERVICES AFTER OFFICE HOURS
10. PROTOCOLS FOR INVESTIGATION OF ENDOCRINE DISORDERS
(LH) and Adrenocorticotrophic Hormone (ACTH). Main abnormalities to look for are
Corticotroph deficiency, Thyrotroph deficiency, Gonadotroph deficiency or Somatotroph
deficiency.
Assessment of Anterior Pituitary Reserve
a) Initial assessment
• Morning serum Cortisol and ACTH or Short Synachten Test
• Thyroid Function Test (TSH, FT4)
• Prolactin, LH, FSH
• GH
• Testosterone for man
Estradiol for woman
b) Combine Anterior Pituitary Stimulation Test (Insulin Stress Test +
Gonadotrophin Stimulation Test)
Procedures:
• Fast the patient overnight.
• Insert intravenous catheter or intravenous line.
• Rest patient for 30 minutes. Take samples for glucose, growth hormone,
cortisol, LH, FSH and TSH (as baseline investigation).
• Give insulin 0.1-0.15 unit/kg body weight, 200µg TRH and GnRH 100ug
intravenously.
• Collect samples into plain tubes and Glucose tubes and label as follows:
Time Tests Tube
0 min (basal) Glucose,
Cortisol,FSH,LH
TSH,GH
Glucose tube
1 plain tube
15 min Glucose Glucose tube
20 min FSH, LH, TSH 1 plain tube
30 min Glucose
Cortisol, GH,
Glucose tube
1 plain tube
45 min Glucose Glucose tube
60 min Glucose
Cortisol, FSH, LH,
TSH,GH
Glucose tube
1 plain tube
90 min Glucose,
Cortisol, GH
Glucose tube
1 plain tube
120 min Glucose,
Cortisol, GH
Glucose tube
1 plain tube
* GH-Growth hormone, LH-Luteinizing hormone, FSH- Follicular stimulating
hormone, TSH – Thyroid Stimulating Hormone
Adapted from Clinical Chemistry Sixth Edition, William J Marshall & Stephen K Bangert,
Mosby, 2008, pg 140.
• Label specimens according to sampling time.
• Send all samples after test is completed to main counter, Pathology
Department.
Notes:
• Plasma glucose level must fall below 2.2 mmol/L and/or clinical signs and
symptoms of hypoglycaemia (sweating, tachycardia etc) must be observed.
• Additional intravenous insulin may be given if this does not occur by 30 min
and sampling should be prolonged by another 30 min.
• Physician should be in attendance throughout the tests and 50% i.v. dextrose
should be kept by bed side if severe hypoglycemia is documented.
• Giving glucose for severe hypoglycemia does not invalidate the test results.
• Test is contraindicated for patient with seizure, ischeamic heart disease or
cardiovascular insufficiency and in young children.
• Normal ECG is mandatory.
c) Insulin Hypoglycaemic Test:
• Similar as Combine Anterior Pituitary Stimulation Test but without GnRH
injection.
Blood samples are taken at 0 minute (basal), 30 minutes and 60 minutes after
insulin injection for glucose, cortisol and growth hormone (GH) as follows:
Time Tests Tube
0 min (basal) Glucose
Cortisol, GH
Glucose tube 1
plain tube
30 min Glucose
Cortisol, GH
Glucose tube 1
plain tube
60 min Glucose
Cortisol, GH
Glucose tube 1
plain tube
• Label specimens according to sampling time.
• Send all samples after test is completed to main counter, Pathology
Department.
d) Gonadotrophin- Releasing Hormones Stimulation Test:
• Collect samples into plain tubes for LH and FSH (basal sample).
• Give 100 ug GnRH.
• Collect samples into plain tubes at 15 minutes, 30 minutes, 60 minutes and 90
minutes after GnRH injection for Luteinizing Hormone (LH) and Follicular
Stimulating Hormone (FSH).
Time Tests Tube
0 min (basal) FSH, LH 1 plain tube
15 min FSH, LH 1 plain tube
30 min FSH, LH 1 plain tube
60 min FSH, LH 1 plain tube
90 min FSH, LH 1 plain tube
• Label specimens according to sampling time.
• Send all samples to main counter Pathology Department
2. Pituitary surgery assessment
a) Pre-operative assessment
• Morning serum cortisol
• Thyroid Function Test (TSH, FT4)
• Prolactin, LH, FSH
• GH
• Testosterone for man
• Estradiol for woman
b) Post-operative assessment (2-4 days after surgery)
• Steroid coverage with hydrocortisone is administered immediately before,
during and after surgery.
• If adrenal function was normal before surgery, hydrocortisone is stopped on
second or third post-operative day.
• 24 hours after stopping – take morning blood for cortisol
c) Follow up assessment (one month after surgery)
• FT4
• Testosterone for man
• Estradiol for woman
• Cortisol and ACTH at 9.00 am and Short Synacthen test, even if function is
subnormal after surgery. ACTH deficiency after surgery is often transient.
After pituitary irradiation, patient should be evaluated at least once per year with
measurement of FT4, estradiol (if female), testosterone (if male), FSH, LH, prolactin,
cortisol, ACTH and Short Synacthen Test.
3. Acromegaly
a) Screening and biochemical diagnosis • 2 tests must be done to attain biochemical diagnosis of active acromegaly.
• Measure IGF 1 level according to age-adjusted reference.
• Perform oral glucose tolerance test with 75g oral glucose after at least 8
hours of overnight fasting.
• Active acromegaly is indicated by elevated IGF 1 and failure of GH to be
suppressed below 1 ng/ml (3 mIu/L)
• GH may not be suppressed in poorly controlled diabetes mellitus, severe
illness, chronic liver disease and chronic kidney disease.
b) Other biochemical tests (Anterior Pituitary hormones and metabolic Screening) • Serum prolactin
• ACTH and cortisol (morning sample)
• TFT
• LH, FSH, testosterone (male), estradiol (female) – morning sample
• Fasting serum lipids
• RP, uric acid
• LFT, calcium, phosphate
• Urine FEME
Assessment of Posterior Pituitary Hormone
Posterior pituitary secretes vasopressin (ADH) and oxytocin. These hormones are
synthesized in hypothalamus and pass down nerve axons into the posterior pituitary and
released into the circulation.
1. Diabetes Insipidus (DI)
• Lack of ADH caused by pituitary/hypothalamic disease (cranial DI) or failure of
kidney to respond to ADH (nephrogenic DI)
• Presented with polyuria –urine volume >3 L/day
• common causes of polyuria such as diabetes mellitus , hypokalemia ,
hypercalcemia and diuretic therapy have been excluded
• Measure serum and urine osmolality and sodium
If serum osmolality > 295 mOsm/kg, urine osmolality is < 300 mOsm/kg and
sodium >145 mmol/l - Diagnosis of Diabetes Insipidus is likely and not to do
Fluid Deprivation test
• If diagnosis is in doubt; perform Fluid Deprivation test
a) Protocol for Fluid Deprivation Test
Procedure
(**Ensure adrenal and thyroid function normal before contemplating the test)
• Allow fluids overnight before test and give light breakfast with no fluid; no
smoking permitted
• Weigh patient
• Allow no fluid for 8hours; patient must be under constant supervision
• Every 2 hours
- Weigh patient (stop test is weight falls by > 5% initial body weight)
- Measure urine volume and osmolality
- Measure serum osmolality ( stop test if osmolality >300 )
After 8 hours
- Allow patient to drink ( no more than twice urine volume of period of fluid
deprivation, to avoid acute hyponatraemia) and give 2 µg desmopressin i.m
Measure urine osmolality every 4 hours for further 16 hours
Interpretation:
Algorithm for the investigation of polyuria.
Adapted from Clinical Chemistry Sixth Edition, William J Marshall & Stephen K Bangert,
Mosby, 2012, pg 135
normal
fluid
deprivati
on test
Urine osmolality (mmol/kg) after:
8 h fluid
deprivation
desmopressin
<300 >750
<300 <300
>750 >750
300-750 <750
Cranial diabetes
insipidus
Nephrogenic
diabetes insipidus
Primary polydipsia
Non-diagnostic
measure: blood
glucose plasma
creatinine potassium
calcium
polyuria abnormal diagnosis
ADRENAL DISORDERS
Disorders of Adrenal Cortex
1. Adrenal hypofunction (Addison’s Disease)
measure AM Cortisol
<50 nmol/L – diagnostic of adrenal failure
>550 nmol/L – excludes adrenal failure
50-550 nmol/L – ACTH stimulation test (Short
synacten test)
a. Short Synacthen Test
• High index of suspicion is required to diagnose adrenal insufficiency.
• Indications for screening:
– Unexplained hyponatremia.
– Prolonged corticosteroid or traditional medication ingestion.
• Screening is by doing short synacthen test.
Procedure:
• Take blood sample for baseline cortisol level (0 minutes).
• Give 250ug cosyntropin (synthetic ACTH) intramuscularly or intravenously.
• Take samples at 30 minutes and 60 minutes after injection for cortisol level.
Time Tests Tube
0 min (basal) Cortisol 1 plain tube
30 min Cortisol 1 plain tube
60 min Cortisol 1 plain tube
Interpretation:
• Normal response is cortisol increment of 200nmol/L with peak of >550nm/l
• Patient with atrophy of adrenal cortex (exogenous steroid / pituitary or
hypothalamic disease) shows slight rise in serum cortisol.
2. Adrenal Hyperfunction (Cushing’s syndrome)
Screening tests should be done in patients:
– With multiple and progressive features of Cushing syndrome
– With adrenal incidentaloma.
– After excluding exogenous steroid intake.
• Screening tests are:
i. 24-hours urine free cortisol: if level is 3-4 times greater than upper limit
normal, suggestive of Cushing syndrome.If less than 300 nmol/day,
Cushing syndrome is excluded
ii. Overnight Dexamethasone Suppression Test (OLDDST)
Procedure:
- Give 1 mg dexamethasone orally at 2300 or 2400 hours.
- Fill up the request form complete with clinical summary and request test
mentioned above.
- Collect blood at 8.00 am the next morning for determination of serum cortisol
and send to main counter, Pathology Department.
Interpretation: In normal subjects, serum cortisol is suppressed to less than
50 nmol/l. Serum cortisol level of more than 50 nmol/l can also be seen in
cases of stress, obesity, infection, acute or chronic illness, alcohol abuse,
severe depression, oral contraceptive, pregnancy, estrogen therapy, failure to
take dexamethasone, or treatment with diphenylhydantoin or phenobarbital
(enhancement of dexamethasone metabolism).
iii. Low Dose Dexamethasone Suppression Test
Procedure:
- At 9.00am on 1st day of test, collect blood for serum cortisol (basal) and
request test mentioned above.
- Immediately after sampling, give 0.5mg dexamethasone orally every 6 hrs for
2 days (8 times).
- Collect blood for serum cortisol 6 hours after last dose of 0.5mg
dexamethasone and send to main counter Pathology Department.
Note:
• Ensure the times are followed strictly and with full compliance.
Day 1
Day 2
Day 3
Sample taken for
serum cortisol.
0900 am (basal) -
0900 am
Drug given: 0.5mg dexamethasone every 6 hours (8 times)
0900 am 0300 am 0300 am
dose)
(last
1500 pm
0900 am
-
2100 pm
1500 pm
-
-
2100 pm
-
Interpretation:
In normal subjects, serum cortisol will be suppressed to <50nmol/l.
• Localization Test:
• After 2 concordantly positive screening tests, localization tests are
recommended, which include:
iv. Plasma ACTH
Procedure:
– Blood should be taken together with serum cortisol at 9am.
– Keep the tube in ice water bath and send to lab for
centrifuged and frozen as soon as possible to avoid falsely
low result.
Interpretation:
– ACTH < 5 ng/L (<1 pmol/L): ACTH independent Cushing →
proceed with CT scan of adrenals.
– ACTH >15 ng/L (>3 pmol/L): ACTH dependent Cushing →
proceed with MRI pituitary/ CXR.
v. Bilateral inferior petrosal sinus sampling:
For localization of pituitary tumour (Cushing disease).
• Special Endocrinology Test Protocols for Adults ,Endocrinology Unit, Department
of Medicine Hospital Putrajaya, 2010
• Clinical Chemistry Sixth Edition, William J Marshall & Stephen K Bangert, Mosby,
2008
11. REFERENCES