Brucella melitensis endocarditis: successful treatment of an infected prosthetic mitral valve

Abstract

. Brucelha melitensis endocarditis: successful treatment of an infected prosthetic mitral valve. A 38-year-old man had a mitral valve replacement for rheumatic calcific mitral stenosis and regurgitation; following this operation he remained well for 10 months. He then presented with cough, abdominal pain, and rigors, and Brucella melitensis type 3 was repeatedly isolated from blood cultures. His clinical condition deteriorated rapidly and an emergency valve replacement was performed. He was then treated with co-trimoxazole for 12 months and made an excellent recovery. This is the first reported case of brucella endocarditis arising de novo on a prosthetic heart valve. Endocarditis is a rare but serious complication of brucellosis. We report here a case of Brucella melitensis type 3 endocarditis occurring in a patient with a prosthetic mitral valve. CASE REPORTA 38-year-old Italian male restaurant proprietor underwent mitral valve replacement for rheumatic calcific mitral stenosis and regurgitation on 13 January 1972, with insertion of a No. 3 Starr Edwards mitral valve prosthesis type 6520. On the fourth day after the operation he developed a pyrexia with a rigor. Blood cultures taken at this time were sterile but it was known that at least one bottle of intravenous fluid he had received was contaminated with Pseudomonas thomasii (Phillips, Eykyn, and Laker, 1972) and he was accordingly treated with a six-week course of co-trimoxazole to which the organism was known to be sensitive. Following this, the patient made a good recovery and remained well for 10 months, requiring only routine maintenance doses of digoxin and warfarin.In November 1972, he developed a febrile illness with rigors and complained of cough and abdominal pain, and one week later he became progressively dyspnoeic on exertion and orthopnoeic. Blood was taken for culture and treatment was started with amoxycillin. However, his fever persisted and he developed left heart failure, requiring admission to St. Peter's Hospital, Chertsey on 21 November. Amoxycillin was discontinued and further blood cultures were taken. He was transferred to St. Thomas' Hospital on 25 November where more blood cultures were taken before treatment was begun with intravenous ampicillin and intramuscular streptomycin as it was considered that he had endocarditis. Two days later a slow-growing oxidase-positive Gram-negative bacillus was isolated from the blood cultures taken at Chertsey. It was strongly suspected that this organism might be Ps. thomasii and the antibiotic therapy was changed to intravenous cephalexin, trimethoprim, and sulphadiazine. However, the patient's condition deteriorated and cardiac catheterization with angiography was performed on 29 November. Right heart catheterization showed a right atrial mean pressure of 6 mmHg, pulmonary artery pressure of 40/28 mmHg, and pulmonary artery wedge pressure of 33/26 mmHg. Left heart catheterization showed an aortic pressure of 68/35 mmHg and a left ventricular pressure of 75/7 mmHg. Simultaneous pulmonary arter...

A Case of Prosthetic Mitral Valve Endocarditis Caused by Brucella abortus

“…Mitral prosthetic valve endocarditis due to Brucella species has been reported in the literature (4,5,7,8). Prosthetic mitral valve involvement has been detected at a rate of 8.3% in Brucella endocarditis (3).…”

“…Peery and Belter (6) found endocarditis in 35 of 44 cases of fatal brucellosis by necropsy. The most common cause of death in Brucella endocarditis is congestive heart failure (6,7). The optimal management for Brucella endocarditis, particularly the role of surgery, its timing and the choice and duration of antimicrobial therapy, are unclear.…”

Brucella endocarditis in prosthetic valves

“…The infection of a previously healthy valve most often involves the aortic valve, whereas secondary infections of predamaged valves preferably occur on mitral valves (20). B abortus and B melitensis are reported to be the most frequently isolated species.…”

“…Brucella prosthetic valve endocarditis on mechanical and bioprostheses has been described frequently (5,(12)(13)(14)(15)(16)(17)(18)(19)(20)(21). In endemic areas, such as Saudi Arabia, Brucella has established a high incidence (approximately 10%) among the causative agents of prosthetic valve endocarditis (12,15).…”

“…Some examples of these are myocardial abscesses and aneurysms (5,11); cusp perforation (25); ruptured chordae tendineae and detached leaflets (22); left ventricular failure; disseminated intravascular coagulation (28,29); and embolic phenomena (ie, mycotic aneurysms [15], transient ischemic attacks, myocardial and other organ infarctions [10,20,22,30]). Septic emboli dislodged from valve vegetations may cause infected infarcts of any organ, leading to relapse (21).…”