Approach To A Child With Short Stature

Anju Virmani

1. Measure child's and both parents' heights (cm.) accurately. Assess stage of puberty. Ask if any previous height measurements available, and plan to follow up for growth velocity (see point 8).
2. Calculate midparental height [boys= (father + mother +12)/2; girls=(father -12+ mother)/2]; see which percentile MPH fits with: this will be the centile the child is likely to follow.
3. Plot these (child's height, MPH) on charts of most appropriate normal standards. The most current, all-India standards are those published in Indian Pediatrics, October 1992. Alternatively, Tanner curves can be used. Assess child's height in relation to MPH centile.
4. Child is short if (i) height is less than 3rd percentile of standard for child's age and MPH; or (ii) growth velocity is low (< 5-6 cm/yr. from age of 3 years till onset of puberty) based on previous height measurements (if measurements likely to be accurate, and are over a period of at least 6-12 months).
5. Do screening tests: Hemoglobin, total and differential counts, peripheral smear, serum proteins, creatinine, calcium, phosphorus, alkaline phosphatase, T4 & TSH; urine microscopy, pH (for renal tubular acidosis); stool exam; X-rays of lateral skull (for size and calcification of sella) and left hand and wrist (for bone age).
6. Treat for worm infestations, anemia, other deficiencies, poor diet, infections, hypothyroidism, as indicated.
7. Rule out skeletal dysplasia, IUGR, major dysmorphism, as any treatment is less likely to benefit.
8. Reassess height and pubertal development at 3 monthly intervals:calculate growth velocity only after minimum 6 months.
9. If bone age >15 years or menarche attained (in girls), or bone age > 18 years (in boys): do screening tests (see point 12) and follow up: there is little advantage in looking for GHD as there is hardly any potential for further growth.
10. Only if short (point 4), and euthyroid, test for growth hormone deficiency as follows (single, basal sample is USELESS):
    1. Single sample after 20 min. vigorous exercise (e.g. climbing stairs):
       if > 10 ng/ml, no deficiency.
       If < 10 ng/ml, do stimulation test:
       
       
    2. Using (i) clonidine ( 4 ug/kg or 150 ug/m2) or (ii) Levodopa (125 mg., 250 mg. & 500 mg. at <10 kg., 10-20 kg., and>20 kg. respectively) + propanalol (0.75 mg./kg.):
       • sampling at 0, 30, 60, 90, 120 min:
       • all samples to be tested separately.
       • If ANY level > 10 ng/ml, no deficiency. If all levels < 10 ng/ml, refer to pediatric endocrinologist for GH treatment.
11. Turner syndrome may benefit from GH treatment. For screening, FSH can be done in all girls older than 8 years (see point 5): if high, refer to pediatric endocrinologist.
12. GH treatment must be for a minimum of 1 year; ideally till growth potential remains (completion of puberty); with periodic monitoring of thyroid status. If other cause of short stature found (eg. RTA, malabsorption), treat accordingly.