Streptococcus vestibularis bacteremia following dental extraction in a patient on long-term hemodialysis: a case report.

Abstract

Sir, Streptococcus vestibularis is a normal inhabitant of vestibules of the human oral cavity, and it has rarely been associated with human disease except that two cases of infectious endocarditis of the prosthetic valve [1,2], early neonatal sepsis and bacteremia in both cancer and rheumatic valve disease patients [3–5]. A 24-year-old woman, a known case of end-stage renal disease on haemodialysis was admitted with severe toothache, fever and malaise for a 2-week duration. Dental caries of the upper second molar were found by an expert dental surgeon, the carious tooth was removed and the pain was relieved. However, she developed fever and malaise again 2 days following tooth extraction. She had no symptoms of infection of the upper or lower respiratory, gastrointestinal or genitourinary systems. On physical examination her temperature was 38°C, heart rate was 92 bpm and blood pressure was 130/ 80 mmHg. Her oral hygiene was very poor. Cardiovascular system examination showed a grade 2/6 functional ejection systolic murmur at the lower left sternal edge. There were no clinical findings specific to bacterial endocarditis, either clinically or radiologically. (A trans-esophageal echocardiogram was done to rule out infective endocarditis.) Her leukocyte count was 11 900 cells/L (92% neutrophils), CRP 55 mg/L and ESR 54 mm/h. We thought that the subclavian catheter (inserted because of a–v fistula disfunction) could have been infected but there were no exit-site features of infection. Vancomycin (1 g iv, three times a week, post-HD) was started immediately. Her temperature returned to normal 48 h later. The patient had no complaints of malaise 3 days later. Two blood cultures grew gram-positive cocci. Subcultures grown on solid media showed S. vestibularis by identification kits (BBL Crystal Gram-Positive Identification Kits®). The microorganism was susceptible to vancomycin. Two other blood cultures were taken on the 10th day of vancomycin therapy and they were negative. The patient remained on vancomycin therapy for 18 days, with neither fever nor malaise. On the 18th day the patient's leukocyte count was 6900 cells (72% neutrophils), CRP was 5 mg/L and ESR was 21 mm/h. We stopped vancomycin therapy, and the patient was discharged. Haemodialysis patients are liable to develop blood stream infections following surgical or dental procedures. To our knowledge, ours is the first case of bacteremia caused by S. vestibularis in a haemodialysis patient. We chose vancomycin for treatment as it was shown to be susceptible to vancomycin elsewhere [5]. There is no recommendation for the duration of antibiotic therapy in the literature. We continued the treatment for 3 weeks and stopped therapy after blood cultures were negative. We suggest that in patients with poor dental hygiene and history of orodental surgery, virulent streptococci should be considered. Conflict of interest statement. None declared.