Histopathological study of nephrotic syndrome in adults: A Moroccan report

The reported causes of nephrotic syndrome (NS) varies between different countries. In this retrospective study, we aimed to evaluate the underlying causes of NS in adult patients who underwent renal biopsy in a region of Morocco and we also determined the distribution of histopathological diagnoses with regard to the age subgroups and genders from January 2007 to December 2016. Patients were divided into four groups according to age at the time of renal biopsy. A total of the 257 patients with NS were included in this study. The mean age of the patients was 40.9 ± 16.7 years; male gender was preponderant (61.9%). One hundred and sixty-six (64.6 %) and 81 (35.4%) patients were diagnosed as primary and secondary glomerulonephritis, respectively. The most common diagnosis in NS was membranous nephropathy (MN) (22.2%), followed by minimal change disease (MCD) (20.6%), and lupus nephritis (LN) (13.6%). Among the patients aged 15-30, 31-45, 46-60, and >61 years, the most common cause of NS was MCD (32.1%), MN (29.6 %), MN (26.1%), and amyloidosis (AM) (28.2%), respectively. The proportion of patients with MCD and LN decreased in parallel with patient age and the proportion of patients with renal AM increased in parallel with patient age. Among the female patients aged 15-30 and 31-45 years, LN was the leading cause of NS (41.5 and 36.7%, respectively). Among the male patients aged 15-30 years, MCD was the leading cause of NS (43.2%). Our study over 10 years represents an important data of regional variations of glomerular diseases presenting with adult-onset NS.