Autosomal Dominant Tubulointerstitial Kidney Disease

Autosomal dominant tubulointerstitial kidney disease (ADTKD) is a recently defined entity characterized by tubular atrophy, interstitial fibrosis, and development of chronic kidney disease. Different forms of ADTKD can manifest in childhood; however, due to the slow progressive nature of this condition, renal failure usually develops in adulthood. Initially, ADTKD was known as medullary cystic kidney disease (MCKD). However, after the identification of mutations in Uromodulin (UMOD) as one of the causative genetic defects for MCKD, it became apparent that only approximately 20% of patients with UMOD mutations develop renal cysts and that the medulla is not a specific location for the cysts when observed. Therefore, the name “medullary cystic kidney disease” was considered misleading and contributing to underdiagnosis of this condition. Other terms used for the same condition included familial juvenile hyperuricemic nephropathy (FJHN), hereditary interstitial kidney disease, and tubulointerstitial nephritis. In order to replace these unspecific and misleading names with a more descriptive and accurate term which would also simplify diagnosis, the term “autosomal dominant tubulointerstitial kidney disease” (ADTKD) was created (Eckardt KU, Alper SL, Antignac C, Bleyer AJ, Chauveau D, Dahan K et al, Kidney Int 88:676-683, 2015). A major challenge ofADTKD is the nonspecific nature of clinical and pathological characteristics. To make the correct diagnosis, a family history is helpful and consistent with a dominant pattern of inheritance. Recently, other genes mutations (Mucin-1, HNF1B, Renin, SEC61A1) have also been associated with ADTKD, providing evidence that, in fact, the term ADTKD refers to a heterogeneous disease spectrum with overlapping renal phenotypes caused by at least five different genes (Devuyst O, Olinger E, Weber S, Eckardt KU, Kmoch S, Rampoldi L et al, Nat Rev Dis Primers 5(1):60, 2019). In this chapter, the genetic and clinical heterogeneity, of the pathogenesis, and potential therapeutic approaches for this condition will be discussed.