Diffuse crescentic glomerulonephritis in bacterial endocarditis.

Renal involvement is common in patients with bacterial endocarditis. The most common bacteria are staphylococci and streptococci, and the commonest renal histopathological lesion is a diffuse proliferative and exudative type of glomerulonephritis. Very rarely, patients may present with an extensive glomerular epithelial crescent formation with a rapid deterioration in the renal function. This study reviews the published literature on diffuse crescentic glomerulonephritis in bacterial endocarditis and reports a 24-year-old male patient with endocarditis due to Capnocytophagia species, a gramnegative facultative anaerobic bacillus, which normally inhabits the oral cavity. Appropriate antibiotic therapy is essential to eradicate the infection. A brief course of corticosteroid therapy may be helpful in those with deteriorating renal function. Plasmapheresis may be useful in those with persistent hypocomplementemia, increased circulating immune complexes, and a progressive deterioration in the renal function. Removal of vegetation or valve replacement may be necessary. Prognosis is generally good.