Distal renal tubular acidosis with amelogenesis imperfecta: A novel WDR72 gene mutation

ABSTRACT Renal tubular acidosis (RTA) is a condition where there is a defect in renal tubular excretion of hydrogen ion (H + ) or reabsorption of bicarbonate (HCO 3− ) or both. RTA is of four types: type 1 (distal RTA), type 2 (proximal RTA), type 3 (mixed type 1 and type 2), and type 4 (hyperkalemic RTA). Distal RTA (dRTA) may be inherited or acquired and is caused by impaired H+ ion secretion, leading to impair urinary acidification, resulting in hyperchloremic normal anion gap metabolic acidosis. The inherited (hereditary) form is the most common form of dRTA in children. The hereditary form of dRTA is diagnosed by genetic testing. dRTA due to homozygous pathogenic variations in the WRD72 (tryptophan–aspartate repeat domain 72) gene have also been linked to amelogenesis imperfecta (AI). Dental anomaly associated with dRTA is a rare presentation. This case report represents AI with dRTA associated with a novel mutation in the WDR72 gene.