Nephropathies with pattern of structural alterations of the glomerular basement membrane: Case study

Background The pattern of structural alterations of the glomerular basement membrane comprises two hereditary glomerular diseases: Alport syndrome (AS) and thin basement membrane nephropathy (TBMN); both are rare entities. Material and methods A retrospective, descriptive and observational study was carried out. A sample of 90 cases from Hospital General de Mexico “Eduardo Liceaga” and the Instituto Nacional de Cardiologia “Ignacio Chavez” were obtained over a period of 5 years (2011–2016). The diagnoses provided in all cases were reviewed and the clinical and histological spectrum was described. Data were analysed using descriptive statistics. Results Structural alterations of the basement membrane were found to be more frequent in women (60%), and occurred most frequently in the second decade of life. We found 38 cases (42.22%) compatible with TBMN and 52 cases (57.77%) with ultrastructural changes suggestive of Alport syndrome. Of the cases with characteristics compatible with AS, the majority were men (55.76%) with an average age of 14 years (3–39 years), starting with haematuria (42.30%); in the electron microscopy (EM), the glomerular basement membranes (GBM) measured on average 245.27 nm, with very irregular ranges. The majority of patients with TBMN were women (81.57%) with an average age of 29 years (6–66 years) and with persistent microscopic haematuria at the time of diagnosis (47.36%); in the EM, the GBM averaged 170.63 nm in thickness. Conclusions We report one of the largest case series in Latin America with respect to entities that share a morphological pattern via the study of optical microscopy, that of structural alterations of the glomerular basement membrane. With the EM study, both entities can be suggested.