Immunoglobulin M nephropathy: Histopathological and clinical characteristics. Case series

La nefropatía por inmunoglobulina M (NIgM) es una glomerulopatía idiopática caracterizada por depósitos mesangiales globales y difusos de IgM. Se realizó un estudio retrospectivo de las características clínicas e histopatológicas de los pacientes con NIgM atendidos en nuestro servicio. De 241 biopsias renales, 21 correspondieron a NIgM (8,7 %). Se incluyeron 18 pacientes (14 de sexo femenino, mediana de edad: 3,08 años). Se excluyó a 1 paciente por enfermedad sistémica asociada y a 2 por seguimiento menor a 1 año. Catorce pacientes se manifestaron con síndrome nefrótico (SN) y 4 con proteinuria aislada o asociada a hematuria. En la microscopia óptica, 13 presentaron hiperplasia mesangial, y 5 esclerosis focal y segmentaria. De los pacientes con SN, 7 fueron corticorresistentes, 4 corticodependientes y 3 presentaban recaídas frecuentes. Todos los pacientes con SN y 1 con proteinuria-hematuria recibieron inmunosupresores; los 18 pacientes recibieron, además, antiproteinúricos. Luego de 5,2 años (2-17,5) de seguimiento, 6 pacientes evolucionaron a enfermedad renal crónica.Immunoglobulin M nephropathy (IgMN) is an idiopathic glomerulopathy characterized by diffuse global mesangial deposits of IgM. We retrospectively studied the clinical and histopathological characteristics of the patients with IgMN seen in our service. Of 241 renal biopsies, 21 corresponded to IgMN (8.7 %). One patient was excluded due to associated systemic disease and 2 due to follow-up less than 1 year, 18 were included (14 girls, median age 3.08 years). Fourteen manifested with nephrotic syndrome (NS) and the remaining with proteinuria (isolated or associated with hematuria). On light microscopy, 13 had hyperplasia with mesangial expansion and 5 had focal and segmental sclerosis. Of the patients with NS, 7 were steroid-resistant, 4 steroid-dependent, and 3 frequent relapsers. All patients with NS and 1 with proteinuria-hematuria received immunosuppressants; the 18 patients also received antiproteinuric drugs. After 5.2 years (2-17.5) of follow-up, 6 patients developed chronic kidney disease.Fil: Meni Battaglia, Luciana. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Balestracci, Alejandro. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Toledo, Ismael. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Martin, Sandra M.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Careaga, Claudia Mabel. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Gogorza, María C.. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Caupolican, Alvarado. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); ArgentinaFil: Cao, Gabriel Fernando. Gobierno de la Ciudad de Buenos Aires. Hospital General de Niños Pedro Elizalde (ex Casa Cuna); Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Postdiarrhoeal haemolytic uraemic syndrome without thrombocytopenia

Background: Thrombocytopenia is a hallmark of postdiarrhoeal haemolytic uraemic syndrome (D+ HUS), although it can be transient and therefore undetected. There is scarce information regarding the prevalence and the course of the disease in children with D+ HUS without thrombocytopenia. Objective: To determine the prevalence of D+ HUS without thrombocytopenia and to describe the clinical characteristics of a series of children with this condition. Patients and methods: The medical records of patients with D+ HUS hospitalised between 2000 and 2016 were reviewed to identify those without thrombocytopenia (>150,000 mm3). Demographic, clinical and laboratory parameters of the selected cases were collected and descriptively analysed. Results: Nine cases (5.6%) without thrombocytopenia were identified among 161 patients hospitalised during the study period. Median age at diagnosis was 17 months (7–32) and median prodromal symptom duration was 15 days (7–21). Eight patients maintained normal urine output while the remaining one required dialysis. No patient presented with severe extrarenal compromise and/or hypertension. Conclusions: The prevalence of non-thrombocytopenic D+ HUS was 5.6% and most cases occurred with mild forms of the disease; however, the need for dialysis in one of them indicated that normalisation of platelet count is not always an accurate marker for disease remittance. Our results also confirm that the time of onset of D+ HUS in patients without thrombocytopenia is usually delayed with respect to the initial intestinal symptoms; thus, heightened diagnostic suspicion is necessary