Clinicopathological Study of Immunoglobulin M Nephropathy in Northern Areas of Pakistan.

Immunoglobulin M IgM nephropathy (IgMN) is a controversial entity first described in 1970. Since its inception, the disease remains underdiagnosed because of its diverse clinical as well as morphological presentations and its lack of recognition as a separate distinct entity. We undertook this study, which includes a large number of cases, to better characterize and understand the natural history of this disease. The objective of the study was to determine the clinico-pathological features of patients diagnosed with IgMN. This cross-sectional study was conducted from 1 January 2013 to 28 February 2020 at the Department of Histopathology, Shifa International Hospital, Islamabad. All renal biopsies diagnosed as IgMN were included in the study. A comparative analysis was performed to see the associations of the clinicopathological features with the histological patterns. Univariate analysis was conducted to determine predictors of end-stage renal disease (ESRD). During the study period, 175 (2.80%) cases were diagnosed as having IgMN. The male to female ratio was 1.65:1. The mean age was 28.68 ± 16.19 years. Minimal change disease was the most common histological pattern, seen in 44% (n = 77) of the cases. Of our cases, 89% presented with nephrotic syndrome (NS) and 37.5% of the patients developed ESRD. Mean blood pressure, serum creatinine, treatment type, and response were found to be significantly associated with ESRD. IgMN in our population was frequently seen to present with NS, with variable morphological patterns. It has a poor prognosis with increased resistance to steroids and the frequent development of ESRD.