急速進行性糸球体腎炎

INTRODUCTION: Pediatric rapidly progressive glomerulonephritis (RPGN) encompasses heterogeneous serology-based subtypes, including anti-glomerular basement membrane (anti-GBM), immune-complex-associated, and ANCA-associated (pauci-immune) RPGN. Although these subtypes differ in their underlying immune mechanisms, their ability to predict early renal recovery in children remains uncertain. This study aimed to evaluate the association between serology-based RPGN subtypes and early changes in renal function and tubular injury markers. METHODS: This prospective cohort study included 30 children with newly diagnosed RPGN treated at Dr. Soetomo General Hospital. Patients were classified into anti-GBM, immune-complex-associated, or ANCA-associated RPGN based exclusively on serologic criteria. Estimated glomerular filtration rate (eGFR) and serum kidney injury molecule-1 (KIM-1) were measured at baseline and at 3 months after induction therapy. Primary outcomes were changes in eGFR (ΔeGFR) and serum KIM-1 (ΔKIM-1). Differences among subtypes were assessed using multivariate analysis of variance. RESULTS: Of the 30 patients, 67% had immune-complex-associated RPGN, 20% had ANCA-associated RPGN, and 13% exhibited anti-GBM disease. The median age was 15 years. No statistically significant differences in ΔeGFR or ΔKIM-1 were observed among subtypes (MANOVA, p = 0.506), although numerical improvements varied across groups. CONCLUSION: Serology-based RPGN subtype was not associated with early improvement in glomerular filtration or reduction in tubular injury markers in pediatric RPGN. Early renal recovery may be influenced more by baseline disease severity and therapeutic responsiveness than by serologic subtype classification alone.

Perinuclear antineutrophil cytoplasmic antibodies (P-ANCAs) and myeloperoxidase (MPO) antibodies are detected in 15%-25% of lupus nephritis patients, but systemic lupus erythematosus (SLE)/ANCA-associated vasculitis (AAV) overlap syndrome is rare, occurring in approximately 2% of cases. We present a 57-year-old woman with SLE and antiphospholipid syndrome (APS) on belimumab, hydroxychloroquine, and prednisone, who presented with acute ischemic stroke requiring thrombectomy and rapidly progressive renal failure (creatinine rising from 1.1 to 5.2 mg/dL) with nephrotic-range proteinuria (8.6 g/g). P-ANCA titer was > 1:640 with MPO positivity, while anti-dsDNA, C3, and C4 were normal. Kidney biopsy revealed crescentic glomerulonephritis with neutrophil-rich infiltrates and immune complex deposits on electron microscopy but without "full house" immunofluorescence, favoring SLE/AAV overlap rather than isolated lupus nephritis flare. Treatment with methylprednisolone, rituximab, and anticoagulation resulted in significant renal recovery (creatinine 1.7 mg/dL, proteinuria 4.4 g/g). This case highlights the importance of ANCA testing in SLE patients with unexplained rapidly progressive glomerulonephritis, as early recognition of overlap syndrome carries distinct therapeutic implications, including the use of rituximab-based regimens targeting both disease processes.

Microscopic polyangiitis (MPA) is an ANCA-associated vasculitis that affects multiple organs. However, cardiac involvement is rare in these patients. We herein report a rare case of MPA presenting with marked peripheral edema and weight gain due to acute pericarditis with borderline tamponade physiology and possible effusive-constrictive features, resulting in right-sided heart failure. Myeloperoxidase-ANCA was strongly positive, and the patient subsequently developed rapidly progressive renal dysfunction. A renal biopsy revealed pauci-immune crescentic glomerulonephritis, confirming the diagnosis of MPA. This case highlights pericarditis with pericardial compressive syndrome as an atypical initial manifestation of MPA.

Granulomatosis with polyangiitis (GPA) is a systemic necrotizing small-vessel vasculitis that commonly involves the upper and lower respiratory tracts and kidneys and is potentially life-threatening. Early manifestations may be subtle and misleading, resulting in delayed diagnosis and treatment. Laryngeal involvement, particularly presenting as isolated dysphonia, remains an underrecognized and easily overlooked feature. We report a 77-year-old man with a history of lymphoma and previous lung cancer in remission who presented with six weeks of progressive hoarseness, shortness of breath, profound weight loss, and constitutional symptoms. On presentation, he was found to have multifocal pulmonary opacities, acute kidney injury with active urinary sediment, and systemic inflammation. The constellation of symptoms and his complex medical history created a diagnostic challenge. A unifying diagnosis emerged only after serologic testing revealed positive cytoplasmic anti-neutrophil cytoplasmic antibodies (C-ANCA) and anti-elevated proteinase-3 (PR3) antibodies. Renal biopsy confirmed pauci-immune crescentic glomerulonephritis consistent with GPA. Prompt initiation of pulse-dose corticosteroids and rituximab resulted in rapid clinical improvement. This case underscores dysphonia, which may represent an early and critical clue to airway involvement, preceding fulminant multisystem disease. Recognition of this presentation is essential, as diagnostic delay may lead to irreversible organ damage, whereas timely immunosuppressive therapy can be rapidly life-saving and organ-preserving.

Monoclonal gammopathies of renal significance constitute a heterogeneous spectrum of nephropathies characterised by renal deposition of monoclonal immunoglobulins or their fragments, produced by clonal proliferation of B lymphocytes or plasma cells, in the absence of diagnostic criteria for symptomatic multiple myeloma or overt lymphoma. In recent years, the growing recognition of these nosological entities has highlighted how early diagnosis and the implementation of clone-directed therapeutic strategies can significantly alter the natural history of the disease and improve long-term renal outcomes. Within this complex classification, proliferative glomerulonephritis with monoclonal immunoglobulin deposits is an exceptionally rare histological diagnosis, typically burdened by an unfavourable renal prognosis and a high risk of progression to end-stage renal disease. The peculiarity of this entity lies in the granular non organised deposition of monoclonal immunoglobulins at the glomerular level, which triggers an endocapillary and/or mesangial proliferative process with consequent impairment of filtration function. We present the clinical case of a 65-year-old male patient who developed overt nephrotic syndrome associated with rapidly progressive renal failure. Renal biopsy revealed PGNMID in the context of MGRS underlying marginal zone B-cell lymphoma. The patient underwent combination treatment with high-dose corticosteroids and rituximab, achieving an excellent clinical response characterised by complete remission of the nephrotic syndrome and normalisation of renal function. This case highlights the importance of a multidisciplinary diagnostic approach in MGRS and the potential benefit of clone-targeted therapies in the management of PGNMID, even in the presence of acute deterioration of renal function.