Untreated Hereditary Distal Renal Tubular Acidosis: Severe Skeletal and Renal Complications

Objective To demonstrate the severe radiological consequences of prolonged treatment interruption in hereditary dRTA and emphasize the importance of continuous therapy. Case Presentation A 31-year-old female with genetically confirmed hereditary dRTA (SLC4A1 mutation) presented after a 13-year treatment hiatus. Clinical findings included severe metabolic acidosis (pH 7.19, bicarbonate 12.7 mEq/L), hypokalemia, hypophosphatemia, and persistently alkaline urine (pH 7.0). Radiological examination revealed pathognomonic features of severe osteomalacia including Looser-Milkman pseudofractures, biconcave vertebral deformities, trefoil pelvis configuration, and extensive bilateral medullary nephrocalcinosis. Results The patient demonstrated classical complications of untreated dRTA: progressive skeletal deformities, recurrent nephrolithiasis requiring annual hospitalizations, and chronic kidney disease. Genetic analysis confirmed a heterozygous SLC4A1 variant (c.2704G > T, p. Asp902Tyr). Following treatment reinitiation, biochemical parameters improved but structural deformities remained irreversible. Conclusion This case provides exceptional radiological documentation of severe complications from untreated hereditary dRTA. Early diagnosis and continuous alkali therapy are crucial to prevent irreversible skeletal and renal damage. The radiological findings serve as important