Juvenile versus Adult Types of Alport Syndrome . Schneider first recognized that males in some kindreds with Alport syndrome experienced ESRD in childhood or adolescence, while in other kindreds, males that had ESRD were middle-aged. Major Types of Alport Syndrome . Our analysis of 65 kindreds indubitably suffers from nonuniformity of diagnostic criteria in the original reports, but most fit the following classification well. Type I Alport Syndrome is dominantly inherited juvenile type nephritis with hearing loss, where affected males have no offspring.
Pedigree analyses are uninformative for X-linked vs. autosomal dominant inheritance.
I is an interim category subject to reclassification because ESRD treatment may now allow the affected males to reproduce, or newer genetic methods may allow chromosomal localization of the nephritis genes. Type V Alport Syndrome is autosomal dominant nephritis with hearing loss and thrombocytopathia. Prevalence of ESRD of females with type V disease may approach that of males, but data are scanty. Nineteen of the 65 kindreds in our retrospective study were unclassifiable. We could not estimate worldwide incidence of Alport syndrome.