Valentin D. Mocanu

Background: Atypical hemolytic uremic syndrome (aHUS) is a rare thrombotic microangiopathy (TMA) caused by complement dysregulation, leading to microangiopathic anemia, thrombocytopenia, and acute kidney injury (AKI). Complement over activation typically results from genetic mutations in alternative pathway proteins. The genetic profile varies regionally and influences clinical phenotype and outcomes. Methods: We conducted a retrospective observational study in all 27 patients (12 children, 15 adults) diagnosed with aHUS, at “Fundeni” Clinical Institute, between January 2017 and January 2025. Median age was 30 years (range, 1–70), 59% female. All patients were treated with anti-C5 monoclonal antibodies and followed for a median of 13 months (9–27). Results: No patient had a family history of aHUS. Infections were the most common trigger (67%). Although 30% had a history of previous events, the median time from latest event to admission was 30 days, reflecting late diagnosis and referral, but the median time from admission to treatment was 8 days. At presentation, 60% of patients required dialysis and all had anemia, but 20% had no thrombocytopenia. AKI was common and the predominant clinical presentation was acute nephritic syndrome. Renal biopsies showed acute-on-chronic TMA with glomerulosclerosis and interstitial fibrosis in 90% and 80% of cases, respectively. Genetic testing revealed CFH/CFHR variants in 39% and CFI variants in 22% of patients. Anti-C5 therapy led to remission of anemia and thrombocytopenia in about 90% of patients, C3 normalization in 90%, and dialysis independence in 74%. No deaths or serious adverse events occurred. Conclusion: In this Romanian aHUS cohort, CFI variants were more frequent than expected, probably reflecting a different geographical distribution. Anti-C5 therapy proved effective and safe. However, limited patient numbers and observational design are study limitations.

(1) Background: We sought to investigate the impact of the COVID-19 pandemic in patients with lupus nephritis (LN); (2) Methods: A total of 95 patients with LN actively monitored in our department between 26 February 2020, when the first case of COVID-19 was diagnosed in Romania, and 1 May 2021, were included in the study. Multivariate logistic regression analysis was performed to identify the independent risk factors for SARS-CoV-2 infection; (3) Results: A total of 15 patients (15.8%) had a confirmed SARS-CoV-2 infection during a total follow-up time of 105.9 patient-years (unadjusted incidence rate: 14.28 SARS-CoV-2 infections per 100 patient-years). Median time to SARS-CoV-2 infection was 9.3 months (IQR: 7.2–11.3). The majority of patients had a mild form of SARS-CoV-2 infection (73.3%), while the remaining had moderate forms. None of the patients had a severe infection or a SARS-CoV-2-related death. The most frequent symptom was fatigue (73.3%), followed by loss of taste/smell (53.3%) and fever (46.7%). Forty percent of those with SARS-CoV-2 infection were hospitalized for a median 11.5 days (IQR:3.75–14). In the multivariate logistic regression analysis, a current oral corticosteroid dose ≥ 15 mg/day was associated with a 7.69-fold higher risk (OR, 7.69; 95%, 1.3–45.46), while the use of hydroxychloroquine was associated with a 91% lower risk for a SARS-CoV-2 infection (OR, 0.09; 95%CI, 0.01–0.59). (4) Conclusions: Our study confirms that the SARS-CoV-2 infection-associated morbidity might only be moderately increased in patients with LN. The current oral corticosteroid dose was the only independent predictor of infection occurrence, while use of hydroxychloroquine was associated with a protective effect.