Relationship between rickets and incomplete distal renal tubular acidosis in children

Abstract

BackgroundIn the Sub Saharan Africa Rickets has now been established to be due primarily to calcium deficiency and sometimes in combination with vitamin D deficiency. The main thrust of management is calcium supplementation with or without vitamin D. An observation was made that some children with nutritional rickets do not respond to this management modality. The recently reported high prevalence of Incomplete Distal Renal Tubular Acidosis (idRTA) in adults with osteoporosis as brought to fore the possibility of this being a possible cause of calcium wastage and therefore the poor response in these group of children with rickets.AimTo determine the prevalence of idRTA amongst a cohort of subjects with ricketsTo show a relationship between rickets and incomplete distal renal acidosisTo determine the response of children with rickets and idRTA to addition of Shohl's solution to therapyMethodologyTwo separate cohorts of children with rickets performed the ammonium chloride loading test to detect those with incomplete renal tubular acidosis. Following identification for idRTA, Shohl's solution was added to therapy of calcium and vitamin D supplementation and their response compared to those without idRTA on calcium and vitamin D supplementation solely.Results50 children with rickets aged from two to six years of age and composed of 29 females and 21males were investigated. Incomplete renal tubular acidosis was found in 38% of them. Prevalence of idRTA was highest amongst those aged 3-6 years of age. Those with idRTA had worse limb deformities, biochemical and radiological parameters than those who hadn't. Rate of response on those with idRTA treated with Shohl's solution was at par with those without idRTA.ConclusionIncomplete idRTA exist amongst children with rickets and should be looked out for in severe rickets and older children. Treatment of idRTA will lead to optimal response and healing of rickets.

Distal Renal Tubular (Type 1) Acidosis- A Case Report

“…5 Refractory Rickets is due to bone demineralisation 3,4 in an attempt to buffer acidosis is seen in Type I variety. Renal calculi is also seen in distal renal tubular acidosis (Type I variety).…”

“…X-ray bones showed widening and fraying of epiphysis-suggestive of Rickets (which did not respond to multiple Vitamin D doses at past. 3 Serum Sodium 132 mEq/L and Potassium 2.6 mEq/L were low in more than one instances. Serum Calcium was low normal (7.5; 7.9 mEq/L).…”

“…-2 SD). Widening of bone ends at elbow, wrist, knee and ankle seen, 3,4 which the mother told to be better after present hospital treatment. Muscle power and tendon jerks are diminished, 5 sensory system unaffected.…”

Clinical Evaluation of Chinese Patients with Primary Distal Renal Tubular Acidosis

“…On the third day, the blood carbon dioxide combining power (CO2CP) and blood and urinary pH values were determined. A patient was defined as dRTA-positive if the blood pH and CO2CP decreased while the urine pH exceeded 5.5 (11)(12)(13) and was diagnosed with incomplete dRTA. dRTA patients with a blood pH of < 3.5 were diagnosed with complete dRTA (5).…”

Renal Rickets, A Severe Form in Children

“…Gilson and others described typical findings of bonedeformity with curving of the legs [4]. Rickets a disease of deficiency is still a common finding in the developing countries amongst the under 5 children, peak age of presentation is between the age 1-3 years, It is being contemplated that the basis of rickets in older children may be through another mechanism or the calcium deficiency which was also observed, not purely a nutritional deficiency [5].…”