Autosomic Dominant Tubulo Interstitial Kidney Disease: Case Report of a New Variant of the UMOD Gene.

Autosomal dominant tubulointerstitial kidney disease (ADTKD) is a low-prevalence pathology mainly associated with pathogenic variants of the UMOD gene. It is characterized by the progressive deterioration of renal function, associated with hyperuricemia and accompanied by a family history of gout or hyperuricemia. Often, clinical variability and a lack of molecular testing results in diagnostic failure to determine the ADTKD-UMOD association. Case presentation: We describe the case of a 14-year-old male who presented to the nephrology service with hyperuricemia, renal ultrasonographic changes, and progression to chronic kidney disease in 4 years. He had a family history of hyperuricemia. A probable genetic disease with an autosomal dominant inheritance pattern was considered, confirmed by the presence of a probably pathogenic variant of the UMOD gene, not previously reported in the literature. Conclusion: The investigation of this case led to the identification of a new variant in the UMOD gene, broadening the spectrum of known variants for ADTKD-UMOD. In addition, in this case, a comprehensive anamnesis, that takes into account family history, was the key point to carry out genetic tests that confirmed the diagnosis suspicion. Directed Genetic tests are currently an essential diagnostic tool and should be performed as long as they are available and there is an indication to perform them.