Clinical Implications of Steroid Therapy for Crescentic Glomerulonephritis and Gemella morbillorum-associated Infective Endocarditis

A 54-year-old man was admitted to our institute with a diagnosis of infective endocarditis (IE) with vegetation on the mitral valve and severe regurgitation due to Gemella morbillorum infection together with renal dysfunction, which was eventually diagnosed as infection-related pauci-immune necrotizing crescentic glomerulonephritis. Given the refractoriness to antibiotics, the persistent activity of nephritis, and repeated cerebral hemorrhaging, we prioritized steroid therapy over early surgical mitral valve replacement. Following steroid therapy, the glomerulonephritis completely improved. Although the administration of steroid therapy in the active phase of IE remains controversial, it might be indicated if comorbid glomerulonephritis is critical.