The First Case of Lipoprotein Glomerulopathy in a Patient With Male Infertility.

Lipoprotein glomerulopathy (LPG) is a rare hereditary glomerular disease with lipoprotein thrombi deposition in glomerular capillaries, which is caused by pathogenic variants in APOE gene. Limited research has theoretically suggested that APOE gene mutations might affect sperm quality and contribute to male infertility. However, there have been no reports documenting the occurrence of LPG and male infertility in the same individual worldwide. Herein, we report a 36-year-old slim man who presented with nephrotic syndrome and had abnormal sperm quality. Kidney biopsy confirmed the diagnosis of LPG based on apolipoprotein E (ApoE) deposition. A pathogenic mutation in APOE (c.127C>T; p.Arg43Cys) was discovered by whole-exome sequencing. The patient was sensitive to lipid-lowering treatment, successfully achieving the remission of proteinuria within one month of therapeutic intervention. Furthermore, after four months' treatment the patient's wife conceived naturally and ultimately gave birth to a full-term infant. We highly emphasize the importance of timely renal biopsy and subsequent gene screening in similar clinical cases.