Overlapping Atypical Hemolytic Uremic Syndrome and C3 Glomerulopathy with Mutation in CFI in a Japanese Patient: A Case Report.

A 34-year-old Japanese man presented with blurred vision, headache, nausea, anemia, thrombocytopenia, and severe renal dysfunction. Thrombotic microangiopathy was initially suspected to have been caused by malignant hypertension. Antihypertensive medications did not improve his thrombocytopenia or renal dysfunction, and other diseases causing thrombotic microangiopathy were ruled out. Therefore, the patient was diagnosed with atypical hemolytic uremic syndrome. A renal biopsy revealed an overlap of thrombotic microangiopathy and C3 glomerulopathy. Genetic testing revealed c.848A>G (p.Asp283Gly), a missense heterozygous variant in the gene encoding complement factor I. Overlapping atypical hemolytic uremic syndrome and C3 glomerulopathy with complement factor I mutation is very rare, especially in Japan.

Severe systemic inflammation mimicking TAFRO syndrome following COVID-19.

TAFRO syndrome is a rare systemic inflammatory disease. Its pathogenesis mainly involves excessive cytokine secretion and autoimmune dysfunction. Although its etiology is unclear, some viral infections have been reported to cause it. Here, we report a case of severe systemic inflammation mimicking TAFRO syndrome that arose after COVID-19. A 61-years-old woman suffered from a continuous fever, ascites, and edema after contracting COVID-19. She developed progressive thrombocytopenia, renal failure, and elevated C-reactive protein levels. She was tentatively diagnosed with multisystem inflammatory syndrome in adults (MIS-A) and received steroid pulse therapy. However, she exhibited worsening fluid retention and progressive renal failure, which are not typical of MIS-A. A bone marrow examination showed reticulin myelofibrosis and an increased number of megakaryocytes. Although a definitive diagnosis of TAFRO syndrome was not made according to current diagnostic criteria, we determined that her symptoms were clinically consistent with those of TAFRO syndrome. Combination therapy, including steroid pulse therapy, plasma exchange, rituximab, and cyclosporine, improved her symptoms. There are pathological similarities between hyperinflammation that arises after COVID-19 and TAFRO syndrome in terms of the associated cytokine storms. COVID-19 may have triggered the development of systemic inflammation mimicking TAFRO syndrome in this case.

Living-Donor Kidney Transplantation Performed in a Low-Volume Center by Visiting Surgeons From a High-Volume Center and Managed Clinically Solely by Nephrologists: 1-Year Outcomes.

BACKGROUND: Little is known about the outcome of living-donor kidney transplantation (LDKT) performed in low-volume centers lacking the services of full-time transplant surgeons. This retrospective cohort study assessed the outcome of LDKT performed in a low-volume center by visiting transplant surgeons from a high-volume center and managed perioperatively by transplant nephrologists. METHODS: We compared Japanese adult patients who had no donor-specific antibodies and underwent LDKT between 2006 and 2015 either in a low-volume (n = 31) or high-volume (n = 481) center. In the low-volume center, visiting transplant surgeons from the high-volume center conducted LDKT and transplant nephrologists managed the recipients peri- and postoperatively. The primary outcome was the composite of infection, cardiovascular disease, or cancer during 1-year follow-up. The outcomes of the low- and high-volume centers were compared using 1:2 propensity score matching. RESULTS: After matching, 9 of 29 patients in the low-volume center (31.0%) and 16 of 58 patients in the high-volume center (27.6%) experienced the primary composite outcome (risk ratio = 1.13; 95% confidence interval, 0.57-2.23). There were no significant differences between the 2 groups in graft function at 1 year, all-cause graft loss, biopsy-proven rejection, and urological complications. However, the median duration of post-LDKT hospitalization was significantly longer in the low-volume center than in the high-volume center (23 and 16 days, respectively). CONCLUSIONS: Among Japanese patients without preformed donor-specific antibodies, LDKT conducted at a low-volume center by visiting transplant surgeons from a high-volume center and managed clinically by transplant nephrologists was not associated with significantly higher risk of postoperative complications.