A novel frameshift PKD1 mutation in a Chinese patient with autosomal dominant polycystic kidney disease and azoospermia: A case report

Abstract

Autosomal dominant polycystic kidney disease (ADPKD) is primarily caused by mutations in polycystin 1, transient receptor potential channel interacting (PKD1) and PKD2, and characterized by numerous cysts in various organs, primarily the kidneys and liver. The present case report is on a 33-year-old Chinese male patient who suffered from abdominal pain and hypertension, and presented with long-term infertility. Laboratory tests indicated that the patient had a normal renal function, while abdominal computed tomography demonstrated that the patient had enlarged kidneys with a volume of 1,127.21 cm3. In a semen analysis, no sperm was detected, while a subsequent testicular biopsy analysis demonstrated numerous mature sperms with progressive motility which suggests that the cysts of the epididymis and the dilated seminal vesicles may have obstructed the ejaculation of semen. Genetic testing identified that a novel missense mutation (c.9053delT) that was responsible for the disease. ADPKD has various disease severities, which depend on whether there is a PKD1 or PKD2 mutation and whether the mutation impairs the function of the polycystin protein. Therefore, genetic testing is important for the clinical diagnosis and prognosis of ADPKD patients, as well as prenatal diagnosis.1.5 million individuals are affected in China (1-4). A common cause of ADPKD is a mutation in polycystin (PC)-1, a transient receptor potential channel which interacts with (PKD1) and/or PKD2, and accounts for 85 and 15% of all detectable cases of ADPKD, respectively. Approximately 10% of patients with ADPKD have no detectable PKD1 or PKD2 mutation, which may be attributed to the current lack of effective testing methods or to similar kidney cysts caused by other gene mutations (5,6). ADPKD is characterized by numerous enlarged cysts in the bilateral kidneys and liver, in addition to specific rare manifestations in other organs, including the pancreas, cerebral vasculature, aortic arch and seminal vesicles (7-10). In the case of the present study, a novel frameshift PKD1 mutation was identified in ADPKD, which additionally caused epididymal cysts and azoospermia.