Native valve infective endocarditis at Siriraj Hospital, 1982-1989

During January 1982 to June 1989, there were 105 evaluable adult cases of native valve infective endocarditis admitted to Department of Medicine, Siriraj Hospital. The incidence was approximately 2.6 per 1,000 admissions. The male to female ratio was 1.4 and the mean age was 31.6 years. Thirty (28.5%) were cases associated with intravenous drug abuse. All non-addicts had pre-existing cardiac lesions susceptible to endocarditis especially rheumatic mitral regurgitation, aortic regurgitation, VSD and PDA. The clinical features of cases without intravenous drug abuse were low grade fever for few weeks, malaise, dyspnea and heart murmur. The addicts with endocarditis presented with acute febrile illness and pulmonary symptoms. Mucocutaneous embolic lesions were detected in one third of the patients. Echocardiography detected vegetations in 50 per cent of the patients. Streptococci were the most common causative agent in 93 per cent of non-addicts whereas the same percentage in addicts were caused by S. aureus. Most of the patients were treated with beta lactams (pen G, ampicillin or cloxacillin) alone or combined with aminoglycosides (streptomycin or gentamicin) for a duration from 10 days to 16 week. Six cases had valve replacement operation due to intractable heart failure and valve ring abscess, 2 had embolectomy of major arteries and 2 had craniotomy due to intracerebral hemorrhage. The overall case fatality rate was 14 per cent. The causes of death were heart failure, cerebral complications and severe pulmonary infections. Clinical response was observed sooner in non-addict patients.