Evaluation Of Short Stature in Children

Dr Tariq Azam khattakMBBS (AM College(

MCPS ,FCPS(Pediatrics(

Growth Physiology

Growth

Environment

HormonesGenetic factors

Dietary factors

•Growth hormone

•Thyroid hormone

•Gonadotrophins

Factors affecting height

Intra uterine Growth factors

NutritionThyroid harmone

Growth Hormone

FSHLHGH

Thyroid

Birth 1 year 2 years 4years 8years Puberty Adult

Normal height pattern

Birth length 50cmOne year 75 cmTwo yrs 87.5 cmThree yrs 93.75 cm growth 4 yrs 100 cm velocity8 yrs 125 cm 6 cm 12 yrs 150 cm per year

Growth ChartsEasy Instrument Monitoring– Growth Velocity– Growth Pattern

Definition

A child whose height is below 2 standard deviations for age and gender

Males

Age (y)

30

34

38

42

46

50

54

58

62

66

70

74

78

Heig

ht (in)

Heig

ht (c

m)

2 4 6 8 10 12 14 16 18 2070

80

90

100

110

120

130

140

150

160

170

180

190

200

0

+2

+1

-1

-2 -2.0 SD (2.3 percentile)

Generally accepted definition of normal range

Etiology of short stature

Physiological– Familial or genetic– Constitutional short stature

Pathological– Malnutrition– Chronic systemic illness– Hormonal deficiency states

SHORT STATURESHORT STATURE

DysmorphicDysmorphic NormalNormal

•Russle Silver•Noonan’s•Turner syndrome•Downs syndrome•Prader Willi•Pseudo-hypoparathyroidism

•Russle Silver•Noonan’s•Turner syndrome•Downs syndrome•Prader Willi•Pseudo-hypoparathyroidism

ProportionateProportionate Dis-Proportionate

Dis-Proportionate

•Constitutional•Familial/genetic•IUGR•Ch Malnutrition•Celiac Disease•Chronic systemic disease (CRF, CLD)•GH Deficiency•Hypogonadism•Hypothyroidism

•Constitutional•Familial/genetic•IUGR•Ch Malnutrition•Celiac Disease•Chronic systemic disease (CRF, CLD)•GH Deficiency•Hypogonadism•Hypothyroidism

•Osteogenesisimperfecta•Achodroplasia•Rickets•Metabolic and storage disorders(short spine)

•Osteogenesisimperfecta•Achodroplasia•Rickets•Metabolic and storage disorders(short spine)

Most parents contribute short stature to hormonal def. large randomized trials have shown only 5% cases are attributed to hormonesMost common cause is malnutrition in developing countries Familial or constitutional is the leading cause in developed countries

Approach to a child with short stature

History Physical examination Height of the childHeight of parentsPlotting on growth chartworkup

History

Birth historyNutritional historyChronic disease history (asthma, CHD, CLD,CRF, chronic diarrhea)Drugs….chronic steroid therapyFamily history

Physical examination

Weight measurement (fat & short….endocrine, thin & short……under nutrition or chronic illnessSystemic examination to rule out systemic illnessskeletal system examination including spineDysmorphic featuresTanner staging

Height measurementsWithout footwear

Heels & back touching the wall

Looking straight ahead

Gentle but firm pressure upwards applied to the mastoids from underneath

US/ LS ratio

Total Arm span

Target height

Target height in cm for a girl = [mother's height in cm + (father's height in cm - 13)] /2

Target height in cm for a boy = [(mother's height in cm + 13) + father's height in cm)] /2

Growth chartTarget centiles

Workup for short stature

Rule out chronic disease (Hemoglobin, hepatic and renal profile)Rule out malabsorption (esp. if history is suggestive)Karyotyping for all females with short stature to rule out turner syndromeX-ray for bone age (usually left wrist)

Bone age

Better correlate with SMRPredictor of future height

Delayed bone age

Constitutional short statureHypothyroidismCeliac diseaseGH deficiency

Familial Vs Constitutional hallmarks of familial (genetic) short stature is normal bone age, normal growth velocity, and predicted adult height appropriate to the familial patternBy contrast, constitutional growth delay is characterized by delayed bone age and predicted adult height appropriate to the familial pattern Patients with constitutional growth delay typically have a first or second-degree relative with constitutional growth delay (menarche older than 15 y, adult height attained in male relatives when older than 18 y)

Growth hormone actions

Growth Hormone

GH receptors

Liver

Synthesis of IGF1

Proliferation of CellsCellular growth

Linear Growth

Metabolic effects

IGF receptors

Growth Hormone

GH receptors

GH receptors Liver

Synthesis of IGF1

Proliferation of CellsCellular growth

Linear growth

Metabolic effects(Anabolic)

IGF receptors

Workup for GH def

endogenous GH is secreted in a pulsatile fashion. These intermittent peaks are greatest after exercise, meals, and during deep sleep. Therefore, measuring a single random serum GH value is of no use in the evaluation of the short child. random serum GH value of more than 10 mg/dL generally excludes GHD, a random low serum GH concentration does not confirm the diagnosis

GH stimulation test

Insulin-induced hypoglycemia is the most powerful stimulus for GH secretion; however, this test also carries the greatest potential for harm.Alternate GH stimulants used successfully are arginine, levodopa, propranolol with glucagon, exercise, clonidine, or epinephrine.GH provocative testing should be done under the supervision of a pediatric endocrinologist

IGF-1 and IFGBP-3 measurement

IGFBP-3 and IGF-1 serum levels represent a stable and integrated measurement of GH production and tissue effectsIGF-1 have superior diagnostic sensitivity and specificity compared with IGFBP 3.The combination of IGF-1 and IGFBP-3 measurements appears superior to determining either analyte alone in the diagnosis of growth hormone (GH) related disorders

Interpretation of results

If IGF-1 and IGBP-3 level are normal then it shows that GH level is also normal (no need for GH testing)

If IGF-1 and IGBP-3 level are low then it may be due to GH def or GH resistance-----go for GH basal level and after stimulation

If GH also low then GH def, if normal or high then GH resistance ( Primary IGF-1 def)

Take Home Message

Take height properly along with the height of parentsPlot on Growth Charts and find out the target centileDetermine the growth velocity by follow up at least after 6 monthsA systematic approach and simple tests like bone age usually reduce the need & hence cost of further investigationsFor dynamic stimulation tests refer the child to specialist centres