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Infective endocarditis due to coagulase-negative staphylococci is increasingly recognized as a difficult-to-treat disease associated with poor outcome. The aim of this report is to describe the characteristics and outcome of patients with prosthetic valve endocarditis (PVE) due to coagulase-negative staphylococci versus those of patients with PVE due to Staphylococcus aureus and viridans streptococci. Patients were identified through the International Collaboration on Endocarditis Merged Database. A total of 54 cases of coagulase-negative staphylococci PVE, 58 cases of S. aureus PVE, and 63 cases of viridans-streptococci-related PVE were available for analysis. There was no difference between the three groups with respect to the type of valve involved or the rate of embolization. However, heart failure was encountered more frequently with coagulase-negative staphylococci (54%) than with either S. aureus (33%; p=0.03) or viridans streptococci (32%; p=0.02). In addition, valvular abscesses complicated 39% of infections due to coagulase-negative staphylococci compared with 22% of those due to S. aureus (p=0.06) and 6% of those due to viridans streptococci (p<0.001). Mortality was highest in patients with S. aureus and coagulase-negative staphylococcal endocarditis (47 and 36%, respectively; p=0.22) and was considerably lower in patients with viridans streptococcal endocarditis (p=0.002 compared to patients with coagulase-negative staphylococcal endocarditis). The results of this analysis demonstrate the aggressive nature of coagulase-negative staphylococcal PVE and the substantially greater morbidity and mortality associated with this infection compared to PVE caused by other pathogens.

The aim of the present study was to compare the epidemiological and clinical characteristics of Streptococcus bovis endocarditis with those of endocarditis caused by oral streptococci, using data obtained from a large international database of uniformly defined cases of infective endocarditis. S. bovis, a well-known cause of infective endocarditis, remains the common name used to designate group D nonenterococcal streptococci. In some countries, the frequency of S. bovis endocarditis has increased significantly in recent years. Data from the International Collaboration on Endocarditis merged database was used to identify the main characteristics of S. bovis endocarditis and compared them with those of infective endocarditis (IE) due to oral streptococci. The database contained 136 cases of S. bovis IE and 511 cases of IE due to oral streptococci. Patients with S. bovis IE were significantly older those with IE due to oral streptococci (63+/-16 vs. 55+/-18 years, P<0.00001). The proportion of streptococcal IE due to S. bovis increased from 10.9% before 1989 to 23.3% after 1989 (P=0.0007) and was 56.7% in France as compared with 9.4% in the rest of Europe and 6.0% in the USA (P<0.00001). Patients with S. bovis IE had more comorbidity and never used intravenous drugs. Complication rates, rates of valve replacement, and mortality rates were similar in the two groups. In conclusion, this study confirmed that S. bovis IE has unique characteristics when compared to endocarditis due to oral streptococci and that it emerged in the 1990s, mainly in France, a finding that is yet unexplained.

We analyzed 50 cases of bicuspid aortic valve endocarditis in patients who presented to St. Thomas' Hospital from 1970 through 1998. These represented 12.3% of the 408 cases of native valve endocarditis (NVE). All patients were male, and their mean age was 39 years. Forty-five of the 50 cases were pathologically proven; 47 were clinically definite according to the Duke criteria and 49 according to our modifications of the Duke criteria. Viridans streptococci and staphylococci accounted for 72% of cases. The prevalences of clinical features were similar to those seen in NVE: fever (temperature >/=38 degrees C, 74%) and malaise (70%), although dyspnea was more frequent (36%). There was a high incidence of serious complications (72% heart failure; 30% periannular abscesses). Surgery was required during the initial admission in 82% of cases. Overall mortality was 14%, and surgical mortality was 9%. Few patients knew they had a "heart condition," and a bicuspid aortic valve was detected in only 35% of echocardiograms performed before surgery.

The clinical and epidemiological features of 120 episodes of Streptococcus pyogenes bacteraemia in St. Thomas' Hospital between 1970 and 1997 were analysed. One-third of episodes were nosocomial. M1 was the most common serotype, and 29% of strains were non-typable. There was a variety of presenting features, but nearly half of the patients had cellulitis, 15% were shocked, and 6% had necrotic infections. There was no focus of infection in 13%. 54% of patients had an underlying disease, and 23% of infections were associated with a medical procedure or device. The mortality rate was 19%, and was associated with shock, coma, no focus of infection, and underlying disease. Since 1989, the annual incidence has more than doubled, and M1 strains and necrotic infections have increased, but the mortality rate and the proportion of patients presenting with shock have decreased, and the increase in cases involved many different M-types.

Metastatic bacterial endophthalmitis is an uncommon and serious infection, that can be caused by a variety of bacteria. Group B streptococci have rarely been implicated. We report four cases of metastatic endophthalmitis in adults caused by group B streptococci. The organisms were isolated from the eyes and blood in each case.

Three clinically typical cases of multiple pyogenic liver abscesses are presented. In all three cases Streptococus milleri was isolated from the pus and in two cases it was isolated from blood cultures also. The patients were successfully treated by surgical drainage and antibiotics.

A case of hepatopulmonary hydatid disease in a Cypriot who presented with pyogenic infection with Streptococcus milleri is described. Although hydatid disease and pyogenic liver abscess are both rare in the UK, an underlying echinococcal pathology should be suspected in any patient from an area endemic for hydatid who presents with a pyogenic hepatic or hepatopulmonary abscess.

In 83 episodes of culture-positive infective endocarditis (IE) of a native valve, fever persisted or recurred in 42 (50%) despite appropriate bactericidal antibiotics. The commonest cause of fever was extensive infection of the valve ring and adjacent structures, even when the infecting organisms were viridans streptococci; urgent surgery was required. Less frequent causes were systemic and pulmonary emboli and drug hypersensitivity. Infected intravenous access sites were seldom responsible. In no case was fever due to antibiotic resistance of the infecting organism. In patients with a definite microbiological diagnosis who have been given appropriate antibiotics, the temptation to alter antibiotic therapy because of persistent or recurrent fever should be resisted unless there are features of drug hypersensitivity. When fever persists or recurs during treatment of IE, the opinions of a cardiologist and cardiac surgeon should be obtained as soon as possible; delay in valve replacement may prove fatal in patients with extensive infection.