Nephrological aspects of complement-mediated thrombotic microangiopathy

Abstract

To analyze cases of complement-mediated thrombotic microangiopathy (C-TMA) in the daily practice of a hospital nephrology department, relative to the general aspects of the clinical course, therapy, and short-term outcomes. The prospective study conducted in the period June 1, 2015 to June 1, 2016 included 10 patients with C-TMA newly diagnosed during hospitalization. Standard demographic parameters, generally accepted clinical data showing the severity of TMA and the involvement of vital organs were recorded at admission. Short-term outcomes of therapy (plasma therapy and/or eculizumab therapy), such as achievement of hematological remission and the need for maintenance therapy and renal replacement therapy (RRT), were evaluate. The median time from the onset of symptoms of the disease to diagnosis in the analyzed cases was 5 months (range 1 week to 26 months). The incidence of C-TMA among the inpatients of nephrology departments was 6.4 per 1,000 patients per year. Five patients were admitted to a clinic with symptoms of obvious extrarenal organ disorders; 4 of them had multiple organ dysfunction. Evident clinical symptoms of renal dysfunction were detected in all the patients, which necessitated RRT in 8 out of the 10 patients. Renal biopsy was performed in 7 patients. All were found to have typical morphological manifestations of acute and chronic TMA. All the patients received plasma therapy; most of them had plasma exchanges; 4 patients took eculizumab. There were no fatal outcomes. All achieved hematological remission. Three of the 8 cases could achieve varying recovery of kidney function and stop dialysis. Analysis of this series of cases confirms the idea about the severity of TMA due to multiple organ dysfunction and the high risk of end-stage renal failure at late diagnosis. The key points of better renal prognosis are the earliest detection and treatment of the disease.