Kawasaki College of Allied Health Professions

This study is a continuation of the Japan Rapidly Progressive GlomeruloNephritis (RPGN) Working Group’s chronological nationwide survey.

We analyzed 1,660 RPGN cases from 2016–2019 and compared them to 4,179 cases from five earlier periods (1989–1998, 1999–2001, 2002–2008, 2009–2011, 2012–2015). Data on causative diseases, clinical severity, 24-month life and renal survival, and treatment details were collected and compared.

The most recent cohort showed an older median age at onset (median age 74 years), with improved serum creatinine levels (median 2.5 mg/dL). Cumulative survival at 24 months remained stable (periods 1989–1998, 1999–2001, 2002–2008, 2009–2011, 2012–2015, 2016–2019 were each 72.0%, 72.9%, 77.7%, 83.0%, 84.9%, 83.5%, p < 0.01), while renal survival showed a favorable trend in the most recent periods (there were each 68.7%, 75.4%, 76.7%, 73.4%, 78.2%, 78.4%, p < 0.01). Anti-neutrophil cytoplasmic antibody-associated vasculitis (AAV)-RPGN had similar outcomes to the overall cohort. Increased rituximab use was observed, with no significant differences in life and renal prognosis between rituximab (RIX) and cyclophosphamide (CY). In severe renal impairment (Cre ≥ 6), renal prognosis was better in the CY or RIX use group than in the non-use group (p = 0.035, 0.025). Anti-glomerular basement membrane disease had a poorer renal prognosis compared to other causes.

Despite an increasingly older age of onset, both life and renal prognoses for new-onset AAV-RPGN from 2016 to 2019 remain comparable to the best in previous surveys, due to the impact of constant improvements in early diagnosis and changes in treatment.

Kidney complications associated with anticancer drug therapy have greatly increased recently. We aimed to investigate the real-world clinical outcomes of anticancer drug therapy–associated renal complications in Japan using the national kidney biopsy database, Japan Renal Biopsy Registry (J-RBR).

From 2018 to 2021, 449 cases from 49 facilities identified as ‘drug-induced’ histopathology in the J-RBR were screened, of which a total of 135 were confirmed as anticancer drug–related cases and included in the analysis. Overall survival rates were estimated using the Kaplan–Meier method and compared by logrank test. The Cox regression model was used to evaluate the association between variables and deaths.

The most common primary sites of malignancies were the lung (33.3%), followed by gastrointestinal (16.3%) and gynaecological (11.1%) cancers. Tubulointerstitial nephritis (TIN; 47.4%) and thrombotic microangiopathy (TMA; 35.6%) were the most frequent diagnoses. All immunoglobulin A nephropathy, minimal change disease and crescentic glomerulonephritis (CrGN) cases were immune checkpoint inhibitor related. All CrGN cases were anti-neutrophil cytoplasmic antibody negative. Antibiotics were most frequently used concomitantly with anticancer drugs in TMA cases among subgroups (TMA versus others: 62.5 versus 27.5%; P &lt; .001). Among TMA cases, the serum lactate dehydrogenase level tended to be higher in cytotoxic agent–associated TMA (CTx-TMA) than in other TMAs, but was not significant between groups (415.5 versus 219.0 U/l; P = .06). Overall survival was worse in CTx-TMA than in other TMAs (P = .007). The Cox model demonstrated proton pump inhibitor (PPI) use (hazard ratio 2.49, P = .001) as a significant prognostic factor, as well as the presence of metastasis and serum albumin level.

Our registry analysis highlighted various presentations of biopsy-proven kidney complications associated with anticancer drug therapy. Clinicians should be aware of worse outcomes associated with CTx-TMA and the prognostic role of PPI use.

Fabry disease is an X-linked lysosomal storage disorder caused by defective enzyme activity of α-galactosidase A and treated with enzyme replacement therapy (ERT) with recombinant α-galactosidase. ERT reduces left ventricular mass assessed by echocardiography or magnetic resonance imaging. However, electrocardiogram changes during ERT have not been fully elucidated. In the present case, ERT with agalsidase alfa for 4 years decreased QRS voltage and negative T depth along with a reduction of left ventricular mass and wall thickness and improvement of symptoms in a female patient with Fabry disease. Long-term observation of electrocardiogram changes might be useful for determining the efficacy of ERT in this case.