35uncommon in children with celiac disease and also adds to growth
impairment.- What is the growth response in children with celiac disease on gluten-free diet?
Gluten-free diet (GFD) is highly effective in the management of celiac dis-
ease. The catch-up growth usually occurs by 6–12 months after introduction
of GFD; however, the gain in weight precedes height gain. Failure to attain
catch- up growth in children with celiac disease who are on GFD for at least
1 year should raise a suspicion of refractory celiac disease, concurrent
autoimmune thyroid disease, growth hormone deficiency, or SHOX
haploinsufficiency.- Why is there growth failure in renal tubular acidosis?
Children with renal tubular acidosis (RTA) may manifest with growth failure.
The impairment in linear growth is a result of chronic metabolic acidosis which
leads to alterations in GH–IGF1 axis, decreased 1α-hydroxylase activity, and
has detrimental effects on epiphyseal growth plate. Metabolic acidosis is asso-
ciated with decreased GH and IGF1 secretion and action and reduced expres-
sion of IGF1 receptor on growth plate. Decreased 1α-hydroxylase activity
results in reduced 1,25(OH) 2 D levels, which lead to impaired endochondral
ossification. In addition, metabolic acidosis per se has deleterious effects on
hypertrophic chondrocytes at growth plate.- How to treat a child with short stature due to renal tubular acidosis?
The aim of therapy in a child with RTA is to correct metabolic acidosis in order
to promote growth and prevent further progression of skeletal deformities.
Therefore, early diagnosis and optimal treatment with oral alkali, either as
bicarbonate or citrate, is recommended. However, citrate is preferred over
bicarbonate, as it is better tolerated. The recommended dose of oral alkali
(bicarbonate or potassium citrate) is 10–20 mmol/Kg daily in divided doses in
proximal RTA (higher doses are required due to massive urinary loss of bicar-
bonate), while 1–2 mmol/Kg daily in distal RTA. Short-term administration of
potassium, calcitriol, and phosphate may be required in these patients.
Overcorrection with alkali should be avoided as it may worsen hypokalemia
and hypercalciuria. During follow-up, serum potassium, pH, bicarbonate, and
urinary calcium should be periodically monitored. In addition, renal ultraso-
nography should be performed at regular interval for the detection of
nephrocalcinosis.1 Disorders of Growth and Development: Clinical Perspectives