Pediatric Renal Rickets

A new study presented a clinical and etiological profile of 19 children with renal rickets managed between 2021-2022. The median age of presentation was 60 months, and the commonest cause was renal tubular acidosis (RTA)––identified in 8 cases. Genetic analysis revealed the diagnosis in 83% of the tested subjects. The reported etiologies of renal rickets included RTA, chronic kidney disease (CKD), hypophosphatemic rickets, vitamin D-dependent rickets (VDDR), chronic liver disease, and malabsorption.

This retrospective case record analysis included data from January 2021 to December 2022, with information on clinical features, biochemical investigations, radiological features, response to therapy, and genetic analysis results. The study found that failure to thrive, polyuria, and polydipsia were consistently present in all RTA patients. Nephrocalcinosis was present in all distal RTA patients, and skeletal deformities were observed in various cases. Hypokalemia and metabolic acidosis were prevalent in RTA and CKD patients.

The study identified specific genetic variations in some cases, such as SLC4A1 variation causing hereditary hemolytic anemia in distal RTA patients. Hypophosphatemic rickets cases showed genetic variations, including one associated with Dent disease. A rare form of refractory rickets (VDDR type 2A) was diagnosed in a 2-year-old boy with a homozygous splice acceptor variant in the VDR gene.

Two deaths occurred in the cohort, one associated with nephropathic cystinosis and the other with chronic kidney disease. The study emphasizes the need for early recognition of non-nutritional forms of rickets based on growth failure, metabolic acidosis, and azotemia. It highlights the importance of clinicians being aware of these indicators for timely diagnosis and management.

Source: Singh A, Sucheta, Gupta R, Abhinay A, Prasad R, Mishra OP.Indian Pediatrics. 2023 Dec;60(12):1039-40.