Yumei Ge

Rationale: Anti-glomerular basement membrane (anti-GBM) antibody disease and antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis represent the 2 leading causes of rapidly progressive glomerulonephritis (RPGN). The coexistence of these conditions is rare, typically progresses rapidly, and has a poor prognosis. Elderly patients often present with nonspecific systemic symptoms, increasing the likelihood of misdiagnosis and treatment delay. Patient concerns: A 74-year-old woman presented with a one-month history of intermittent shortness of breath, worsening progressively over ten days, accompanied by nausea and vomiting. She denied hemoptysis, gross hematuria, rash, or arthralgia. Diagnoses: Initial assessment suggested heart failure. However, laboratory results revealed severe renal impairment (creatinine: 1025.99 μmol/L). Renal biopsy demonstrated crescent formation in over 80% of glomeruli, with immunofluorescence showing linear immunoglobulin G deposits along glomerular capillary loops. Serological testing revealed markedly elevated anti-GBM antibody (>400 RU/mL) and MPO-ANCA (108.4 RU/mL) levels, together with a perinuclear ANCA (P-ANCA) pattern on indirect immunofluorescence, supporting the diagnosis of anti-GBM glomerulonephritis with concomitant MPO-ANCA positivity. Interventions: Treatment included methylprednisolone pulse therapy, cyclophosphamide, and 3 plasma exchange sessions. Additional supportive measures comprised hemodialysis, antihypertensive therapy, and management of renal anemia. Outcomes: Although the patient’s uremic symptoms improved markedly, renal function did not recover. She was discharged on hemodialysis and was subsequently transitioned to maintenance peritoneal dialysis. By January 2026, the anti-GBM antibody level had decreased markedly to 4.27 RU/mL, below the positive cutoff, and MPO-ANCA had also become negative. At the last follow-up in April 2026, the patient remained dialysis-dependent and experienced recurrent hospitalizations for pneumonia, heart failure, and acute pancreatitis. Lessons: This case emphasizes that elderly patients with anti-GBM/ANCA double-positive crescentic glomerulonephritis may initially present with nonspecific symptoms, increasing the risk of incorrect diagnosis. Although combination therapy resulted in symptomatic improvement and serological remission, renal function failed to recover and dialysis dependence persisted. Screening for anti-GBM antibody and ANCA should therefore be considered in patients with unexplained rapidly progressive deterioration of kidney function or active urinary sediment, and renal biopsy should be performed promptly when clinically indicated.

Invasive fungal infections caused by Aspergillus fumigatus and other pathogenic fungi represent a major global health threat, with treatment increasingly c

Syphilis is caused by Treponema pallidum and progresses through different clinical stages, with a wide range of clinical manifestations. We report a case of secondary syphilis in which the patient presented with diffuse granuloma annulare–like lesions involving the neck, chest, abdomen, back, and upper extremities. Clinically, the lesions manifested as annular plaques with raised erythematous borders, accompanied by central ulceration and necrosis. The diagnosis of secondary syphilis was confirmed by skin biopsy and serological examination. Following treatment with benzathine penicillin G, the non-treponemal test (TRUST) became negative 7 months after therapy. The patient responded well to intravenous penicillin treatment, highlighting the importance of early detection and timely therapy in managing syphilis with atypical histopathological features. In recent years, the incidence of syphilis has continued to increase, underscoring the importance of recognizing this clinicopathological presentation. Routine syphilis screening is essential for accurate diagnosis and appropriate treatment.

Liquid-liquid phase separation (LLPS)-mediated formation of membraneless, biomolecule-rich organelles formed via LLPS is critical to numerous biological processes, but how this spatiotemporal control enables efficient catalysis by biosynthetic enzymes to produce natural products (NPs) remains poorly understood. Here, we demonstrate that two C7/C6-dimethylallyl tryptophan synthases (DMATSs), IsaA/InaA and a tryptophanase IsaB, from Streptomyces possess intrinsically disordered regions (IDRs) to undergo LLPS. IDRs from IsaA/InaA are required for enzyme activity, while the IDR from IsaB is not, but it mediates enzyme interaction and preferentially undergoes inter-IDR condensation with IsaA, leading to stronger LLPS and efficient catalysis of cascade reactions to produce isoprenyl alkaloids. These properties were leveraged for enzyme engineering with the IsaA IDR to enhance the catalytic efficiency of taxadiene synthase, and with interactive IDRs from IsaA/IsaB to improve the production of taxadiene and farnesyl-pyrophosphate. Our work proposes LLPS-mediated catalysis regulation and demonstrates new orthogonal toolkits for efficient biosynthesis of isoprenoid NPs.

Traditionally, Pseudonectria foliicola has been considered to have high host specificity, mainly infecting boxwood and causing typical leaf spot disease, w

Aspergillus candidus (A. candidus), while an uncommon clinical isolate, represents an emerging cause of severe invasive fungal disease, particularly among

Nocardia spp. are zoonotic pathogens that can cause infections ranging from localized lesions to systemic dissemination, primarily via pulmonary inhalation or percutaneous inoculation. We report the first confirmed case of Nocardia africana pneumonia with SARS-CoV-2 co-detection in mainland China, diagnosed through bronchoalveolar lavage fluid (BALF) analysis using metagenomic next-generation sequencing (mNGS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). A 76-year-old male presented with persistent cough and fever, accompanied by radiographic evidence of progressive pneumonia. Targeted antimicrobial therapy with trimethoprim-sulfamethoxazole and amoxicillin-clavulanate resulted in clinical resolution within 12 days. This case underscores three critical implications for post-COVID-19 pandemic medicine: the requirement for heightened vigilance for opportunistic pathogens (eg, Nocardia species) in pneumonia patients with recurrent fever, the essential role of advanced diagnostics (eg, mNGS and MALDI-TOF MS) in identifying fastidious organisms like actinomycetes, and the potential for antimicrobial resistance in N. africana, which necessitates susceptibility-guided therapy.