Rupture of Infected Splenic Artery Aneurysm Secondary to Infective Endocarditis
Infected splenic artery aneurysm is a rare but, if ruptured, serious complication of infective endocarditis.1 We report the case of an individual with infective endocarditis who suddenly died during the antibiotic therapy. A 48-year-old man was admitted with a 2-month history of slight fever, general malaise, leg edema, and decreased urine output. He had no history of heart disease, tooth extraction, or drug addiction. On physical examination, a grade-3 systolic murmur was heard at the cardiac apex and marked edema was noted in the lower legs. Laboratory tests showed a white blood cell count of 21 800/mm3 (90% of which were neutrophils), serum C-reactive protein of 17.6 mg/dL, blood urea nitrogen of 51.5 mg/dL, serum creatinine of 7.37 mg/dL, and marked proteinuria and hematuria. Blood cultures obtained on admission were positive for α hemolytic streptococcus. Electrocardiography showed no abnormal findings, except for sinus tachycardia (Figure 1). Transthoracic and transesophageal echocardiography revealed a seaweed-like vegetation attached to the mitral valve ring (Figure 2) and severe mitral regurgitation. Abdominal computed tomography revealed enlarged bilateral kidneys and no abnormal findings in the spleen and splenic artery (Figure 3). On the basis of these findings, infective endocarditis complicated with renal failure was diagnosed, and intensive antibiotic therapy with sultamicillin and meropenem was started. Because the serum creatinine level increased to 9.17 mg/dL on the fourth hospital day, the short-term corticosteroid therapy (intravenous methylprednisolone 0.5g per day for 3 days, then oral prednisolone 30 mg, 20 mg, and 10 mg per day each for 3 days, respectively) was added.2 On the 16th hospital day, the patient’s symptoms improved and serum C-reactive protein and creatinine level decreased to 2.92 mg/dL and 2.84 mg/dL, respectively. Nevertheless, the patient suddenly went into shock after cardiopulmonary arrest and died despite resuscitative efforts on the 24th hospital day. The autopsy revealed massive bloody ascites over 2000 mL and a ruptured infected aneurysm, ≈2 cm in diameter, on the distal portion of the splenic artery (Figure 4). An autopsy specimen of the kidney showed typical crescentic glomerulonephritis (Figure 5). The present case was finally diagnosed as infective endocarditis complicated by rapidly progressive glomerulonephritis2 and infected splenic artery aneurysm with rupture.1 The overlap of these extracardiac complications, probably different in their causes, was thought to be extremely rare in a patient with infective endocarditis. In the present case, the additional steroid therapy for infective endocarditis-induced rapidly progressive glomerulonephritis was effective in recovering renal function, but it may have exacerbated infected aneurysm formation and rupture of the splenic artery.