Primary Hyperoxaluria type 3, first case reported in Uruguay

Rodolfo X. Flores-Bravo, Servicio de Nefrología, Centro Asistencial del Sindicato Médico del Uruguay, Institución de Asistencia Médica Privada de Profesionales Sin Fines de lucro (CASMU-IAMPP), Montevideo, Uruguay
Rosario Gueçaimburú-Ehuletche, Centro de Referencia Nacional de Defectos Congénitos y Enfermedades Raras (CRENADECER), Uruguay
Alejandro Ferreiro, Servicio de Nefrología, Centro Asistencial del Sindicato Médico del Uruguay, Institución de Asistencia Médica Privada de Profesionales Sin Fines de lucro (CASMU-IAMPP); Centro de Nefrología del Hospital de Clínicas, Universidad de la República. Montevideo, Uruguay

Primary hyperoxaluria (PH) comprises a heterogeneous group of autosomal recessive disorders of glyoxylate metabolism. Three genotypic forms (PH1–PH3) are recognized, and diagnosis can be challenging because of marked phenotypic heterogeneity. PH3, the least common form, is caused by pathogenic variants in the HOGA1 gene and generally follows a milder clinical course than PH1 and PH2. We report the case of a young woman with mild hyperoxaluria and preserved renal function with a genetic diagnosis of PH3. Genetic testing identified two pathogenic HOGA1 variants: c.208C>T, p.(Arg70Ter) and c.700+5G>T. This case highlights the broad clinical spectrum of PH3 and underscores the importance of genetic testing in establishing the diagnosis.

Keywords: Primary hyperoxaluria type 3. Oxaluria. Urolithiasis. HOGA1.