IntroductionBecause of their rarity in men, systemic lupus erythematous and lupus nephritis (LN) are poorly understood in men. Our aim was to analyze the clinical presentation and course of histology-proven systemic lupus erythematous and LN in males and to determine the risk factors for progression to end-stage renal disease.MethodsFifty patients from 2 historical cohorts in Spain (Hospital 12 de Octubre) and Uruguay were retrospectively analyzed and compared with a female cohort matched for age and disease characteristics.ResultsThe median age at the time of renal biopsy was 27 years (range, 8–79 years). The main forms of presentation were nephrotic syndrome in 26 of 50 patients (52%), and class IV LN in 34 of 50 (68%). After treatment, 21 patients (45.6%) achieved complete renal remission. During follow-up, 12 patients required renal replacement therapy, and 3 patients died of infectious causes. When patients who required renal replacement therapy were compared with those who did not require it, several parameters showed significant differences (P < 0.05) at the time of renal biopsy: estimated glomerular filtration rate < 60 ml/min, hypertension, hypoalbuminemia, and concomitant visceral involvement (neurologic, cardiovascular, and/or pulmonary). In the multivariate analysis, only estimated glomerular filtration rate < 60 ml/min persisted as a risk factor for progression to end-stage renal disease. When compared with a cohort of female patients with LN, there were no significant differences in remission or renal survival.DiscussionLN in males usually presents as nephrotic syndrome, and type IV LN is the most frequent form. An estimated glomerular filtration rate < 60 ml/min at the time of renal biopsy is associated with poor renal outcomes. There were no differences in remission or progression of LN in males when compared with a cohort of female patients with LN.

Background Acute interstitial nephritis (AIN) is an emerging cause of acute kidney disease. While this disease usually follows an acute course, it may occasionally recur, representing a major challenge for the clinician. Methods We performed a retrospective, observational cohort study in 13 nephrology departments belonging to the Spanish Group for the Study of Glomerular Diseases. Patients with biopsy-proven AIN between 1996 and 2018 were included. Results The study group consisted of 205 patients with AIN, 22 of which developed recurrent AIN (RAIN) after a median of 111 days from diagnosis. RAIN was due to a surreptitious reintroduction of a previously known implicated drug or toxic in six patients (27%), sarcoidosis in two (9%), Sjögren’s syndrome in three (14%), light-chain-mediated AIN in two (9%) and tubulointerstitial nephritis and uveitis syndrome in two (9%), while in the rest of cases (32%), no precise cause could be identified. Microscopic haematuria was more frequent in patients with underlying systemic diseases. The first RAIN episode was treated with a repeated course of corticosteroids in 21 patients (95%). In six cases (27%), azathioprine and mycophenolate mofetil were added as corticosteroid-sparing agents. During a median follow-up of 30 months, 50 patients (27%) with no recurrences and 12 patients (55%) with RAIN reached Stages 4 and 5 chronic kidney disease (CKD). By multivariable logistic regression analysis, RAIN was independently associated with the risk of reaching Stages 4 and 5 CKD, even after adjusting for potential covariables. Conclusions RAIN is infrequent but is associated with poor kidney survival. RAIN should prompt clinicians to search for an underlying aetiology other than drug induced. However, in a large percentage of cases, no precise cause can be identified.

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Aim IgA nephropathy (IgAN), the most common glomerulopathy worldwide and in Uruguay, raised treatment controversies. The study aimed to analyze long-term IgAN outcomes and treatment. Methods A retrospective analysis of a Uruguayan IgAN cohort, enrolled between 1985 and 2009 and followed up until 2020, was performed. The Ethics Committee approved the study. The inclusion criteria were (a) biopsy-proven IgAN; (b) age ≥12 years; and (c) available clinical, histologic, and treatment data. The patients were divided into two groups, with immunosuppressive (IS) or without (NoIS) treatment. Outcomes (end-stage kidney disease/kidney replacement therapy [ESKD/KRT] or all-cause death) were obtained from mandatory national registries. Results The study population included 241 patients (64.7% men), median age 32 (19.5) years, baseline blood pressure <130/80 mmHg in 37%, and microhematuria in 67.5% of patients. Baseline proteinuria, glomerulosclerosis, and a higher crescent percentage were significantly more frequent in the IS group. Proteinuria improved in both groups. Renal survival at 20 years was 74.6% without difference between groups. In the overall population and in the NoIS group, bivariate Cox regression analysis showed that baseline proteinuria, endocapillary hypercellularity, tubule interstitial damage, and crescents were associated with a higher risk of ESKD/KRT or death, but in the IS group, proteinuria and endocapillary hypercellularity were not. In the multivariate Cox analysis, proteinuria in the NoIS group, crescents in the IS group and tubule interstitial damage in both groups were independent risk factors. Conclusion The IS group had more severe risk factors than the NoIS group but attained a similar outcome.