Two matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS)-based methods were compared for their ability to identify viridans streptococci. One approach employed a reference database and software developed in-house. All inhouse measurements were performed using an Autoflex II Instrument (Bruker Daltonics GmbH, Germany). The other system, a VITEK-MS (BioMérieux, France) was operated on the commercially available V2.0 Knowledge Base for Clinical Use database. Clinical isolates of viridans streptococci (n=184) were examined. Discrepant results were resolved by 16S rDNA sequencing. Species-level identification percentages were compared by a chi-square test. The in-house method correctly identified 179 (97%) and 175 (95%) isolates to the group and species level respectively. In comparison, the VITEK-MS system correctly identified 145 (79%) isolates to the group and species level. The difference between the two methods was statistically significant at both group and species levels. Using the Autoflex II instrument combined with an extraction method instead of whole cell analysis resulted in more reliable viridans streptococci identification. Our results suggest that combining extraction with powerful analysis software and the careful choice of well-identified strains included into the database was useful for identifying viridans streptococci species.
DNA, Ribosomal ; Knowledge Bases ; Mass Spectrometry* ; Methods* ; Viridans Streptococci*

Oral viridans streptococci are recognized as one of the etiological agents of a variety of infectious diseases such as dental caries and infective endocarditis. Although antimicrobial susceptibility tests for these fastidious bacterial species are now established and standardized, a comparison between the broth microdilution and broth macrodilution tests has not previously been performed. This comparison was performed in the present study using the tests adopted by the Clinical and Laboratory Standards Institute (CLSI) and seven clinical isolates of oral viridans streptococcal strains. A modified broth macrodilution susceptibility test method was also included in this analysis, in which the media was not supplemented with horse blood. The susceptibility interpretation category agreements were measured at 83% (broth microdilution versus broth macrodilution) and 71% (broth microdilution versus modified broth macrodilution). The interpretation category agreement between the broth macrodilution and modified broth macrodilution tests was also 83%. These data indicate that the interpretation of antibiotic susceptibility test results for oral viridans streptococci are influenced by the methods used.
Communicable Diseases ; Dental Caries ; Endocarditis ; Horses ; Viridans Streptococci

BACKGROUND: We compared the sensitivity and specificity of the newly developed Duke criteria (D) with those of the von Reyn criteria (R), and also evaluated the usefulness of transesophageal echocardiography (TEE) for the diagnosis of infective endocarditis (IE). METHODS: We retrospectively reclassified 99 cases of infective endocarditis either by the Duke criteria or by the von Reyn criteria, according to clinical, microbiologic, and echocardiographic findings. RESULTS: Of 27 histologically confirmed cases, the sensitivity of D (22 definite + 5 possible) was 100%, and that of R (6 probable + 13 possible) was 70.4% (p< 0.05). Of 7 histologically rejected cases, there were 6 possible cases falsely accepted as IE by D, but none were accepted by R (p<0.05). For the histologically confirmed cases, the sensitivity of D was not improved by TEE (23/23, 100%) compared with TTE (23/23, 100%). For 7 histologically rejected cases, the false-positive rate of TEE (5/7, 85.7%) was higher than that of TTE (2/7, 33.3%). There were 2 rejected cases by R compared with 0 by D among 34 cases of IE caused by viridans streptococci (p<0.05). And there were 5 rejected cases by R compared with 0 by D among 11 cases caused by S. aureus. CONCLUSION: The Duke criteria was more sensitive, but less specific than the von Reyn criteria for the diagnosis of IE. TEE may be helpful, but are not specific. The usefulness of TEE should be further evaluated.
Diagnosis* ; Echocardiography ; Echocardiography, Transesophageal* ; Endocarditis* ; Humans ; Korea ; Retrospective Studies ; Sensitivity and Specificity ; Viridans Streptococci

BACKGROUND: The pathogenesis of confluent and reticulated papillomatosis(CRP) is still unknown, although many theories have been suggested. It is stressed that abnormal host response to colonization of pityrosporum orbiculare might play a role in the pathogenesis of CRP, but is not completely understood. Frequently, we have observed bacterial colonies in the stratum corneum and, especially, within the hair follicles from biopsy specimens of patients with CRP. In addition, successful treatment for CRP with minocycline, a derivative of tetracyclines, has been reported continuously. OBJECTIVE: The purpose of this study was to document the possible association of bacterial factors in the pathogenesis of CRP and to elucidate the effectiveness of minocycline. METHODS: We performed Brown and Brenn gram staining in 12 biopsy specimens, bacterial cultures, identification of microorganisms and antibiotics sensitivity testing including minocycline. We administered oral minocycline with an initial dose of 100mg per day for 1 to 3 months and a maintenance dose 50mg per day for I to 2 months, then evaluated the response of treatment. RESULTS: 1. On Brown and Brenn staining, the gram positive bacterial colonies that stained dark bluish or nearly black were observed within the infundibulum of hair follicles in 10 out of 12 biopsy specimens(83.3%) and on the keratotic invagination of stratum corneum in 11 out of 12 biopsy specimens(91.7%). 2. Histological features of regions where bacterial colonies were observed showed, hyperkeratosis and keratotic invagination on the stratum corneum in all cases. Hyperkeratosis(66.7%), parakeratosis(16.7%), inflammatory cell infiltration(25.0%), perifollicular fibrosis(33.3%), and abnormal keratin in sebaceous ducts(50.0%) were shown in hair follicles. 3. In anaerobic cultures, no bacteria was grown. In aerobic cultures, staphylococcus species were identified in 6 cases, streptococcus viridans in one case, sternotrophomonas maltophilia in one case. In the susceptibiliity test, minocycline was sensitive in 7 from 8 cases. 4. The therapeutic response to minocycline was observed within one month in all cases, and the time to clear the lesions was 1/2 month in 2 cases, 1 month in 4 cases, 2 months in 5 cases, 3 months in one case, respectively. CONCLUSION: Form these results, we suggest that bacterial factors may play an important role in the pathogenesis of CRP and that the action mechanism of minocycline in the treatment of CRP may be due to antibacterial effects.
Anti-Bacterial Agents ; Bacteria* ; Biopsy ; Colon ; Hair Follicle ; Humans ; Malassezia ; Minocycline ; Papilloma* ; Staphylococcus ; Tetracyclines ; Viridans Streptococci

PURPOSE: To evaluate the prevalence of contamination of imported donor corneas and their preserved solutions, and to characterize the spectrum of contaminating microorganisms. METHODS: Thirty-seven imported donor corneas and their preserved solutions imported between December 2003 and June 2005 were included in this study. RESULTS: Five imported donor corneas (13.5%) had positive bacterial cultures, and none had positive fungal or mycobacterial cultures. On the other hand, the preserved solutions did not have positive bacterial, fungal, or mycobacterial cultures. One of the 5 imported donor corneas with positive bacterial culture had a mixed bacterial culture. There were 3 isolates of Staphylococcus epidermidis, 1 isolate of Streptococcus viridans, 1 isolate of Enterobacter cloacae, and 1 isolate of Pseudomonas aeruginosa. CONCLUSIONS: The prevalence of contamination of imported donor corneas is low; however, there is a risk of postkeratoplasty infection by contaminated donor corneas. Thus, careful management should be practiced during and after corneal transplant operations.
Cornea* ; Enterobacter cloacae ; Hand ; Humans ; Prevalence ; Pseudomonas aeruginosa ; Staphylococcus epidermidis ; Tissue Donors* ; Viridans Streptococci

Brain abscess is a rare, extremely aggressive, life-threatening infection. It may occur following : infection of contiguous structure, hematogenous spread, or cranial trauma/ surgery. Dental pathology and/or treatment have been linked to a small number of brain abscesses as possible source of infection. 50-year-old male patient was presented with a brain abscess caused by Streptococcus viridans. In the case presented, the significant oral findings were chronic periapical and periodontal infection due to root remnant of lower right 3rd molar. A case history and brief literature review of brain abscess related odontogenic infection was presented after successful treatment with antibiotics and craniotomy.
Anti-Bacterial Agents ; Brain Abscess* ; Brain* ; Craniotomy ; Humans ; Male ; Middle Aged ; Molar ; Pathology ; Viridans Streptococci

Brain abscess is a rare, extremely aggressive, life-threatening infection. It may occur following : infection of contiguous structure, hematogenous spread, or cranial trauma/ surgery. Dental pathology and/or treatment have been linked to a small number of brain abscesses as possible source of infection. 50-year-old male patient was presented with a brain abscess caused by Streptococcus viridans. In the case presented, the significant oral findings were chronic periapical and periodontal infection due to root remnant of lower right 3rd molar. A case history and brief literature review of brain abscess related odontogenic infection was presented after successful treatment with antibiotics and craniotomy.
Anti-Bacterial Agents ; Brain Abscess* ; Brain* ; Craniotomy ; Humans ; Male ; Middle Aged ; Molar ; Pathology ; Viridans Streptococci

Pacemaker lead-related infective endocarditis is an uncommon, but serious complication. We report a case of a 45-year-old man who had symptom of intermittent high fever and rupture of sinus Valsalva that developed after a redo aortic valve replacement and transvenous permanent pacemaker implantation. Positive blood cultures of streptococcus viridans and transesophageal echocardiography showing a large mobile vegetation on pacemaker lead and tricuspid valve lead to the diagnosis of pacemaker lead-related infective endocarditis. Initial antibiotic therapy followed by surgical extraction of the pacemaker lead and wide debridement of infective tissues including multiple vegetations was required. Postoperative antibiotic therapy was continued for 4 weeks. The postoperative course has been uneventful. The patient is totally asymptomatic and is doing well up to now.
Aortic Valve* ; Debridement ; Diagnosis ; Echocardiography, Transesophageal ; Endocarditis* ; Fever ; Humans ; Middle Aged ; Rupture* ; Tricuspid Valve ; Viridans Streptococci

We report herein a case of meningitis due to Streptococcus viridans that occurred after epidural nerve block. The low virulence of S. viridans resulted in milder clinical symptoms and signs than are usually observed for bacterial meningitis, thus mimicking viral meningitis. The infection may have originated from the oral cavity of the medical personnel, and so S. viridans infection should be included in the differential diagnosis of meningitis subsequent to spinal manipulation.
Diagnosis, Differential ; Manipulation, Spinal ; Meningitis ; Meningitis, Bacterial ; Meningitis, Viral ; Mouth ; Nerve Block ; Streptococcus ; Viridans Streptococci

BACKGROUND: Clinical significance of viridans streptococcal bacteremia may be variable from insignificant colonization to serious invasive diseases such as endocarditis. However, there have been no data on the clinical implications of viridans streptococcal bacteremia in Korea to date. MATERIALS AND METHODS: We have analyzed 95 cases of viridans streptococcal bacteremia diagnosed at the Samsung Medical Center from 1997 to 2003. All available clinical and microbiological data were analyzed. RESULTS: Of the total 95 cases, 76 (80%) had clinically significant infections, while 20% of cases were not associated with clinical diseases. Primary bacteremia was the most common disease (48%) followed by intra-abdominal infections (15%), and infective endocarditis (8%). Primary bacteremia was mostly observed in patients with neutropenia after anti-cancer chemotherapy. Infective endocarditis was unlikely if patients did not have underlying heart diseases. S. mitis, S. oralis, and S. intermedius were the most common etiologic agent in infective endocarditis, primary bacteremia, and intra-abdominal infection, respectively. Thirty-eight percent of isolates were not susceptible to penicillin. CONCLUSION: Viridans streptococcal bacteremia is likely to be associated with invasive clinical diseases, especially in patients with neutropenia, intra-abdominal diseases or underlying heart diseases. However, the presence of viridans streptococci in the blood cultures does not necessarily mean the possibility of infective endocarditis.
Bacteremia* ; Colon ; Drug Therapy ; Endocarditis ; Heart Diseases ; Humans ; Intraabdominal Infections ; Korea ; Neutropenia ; Penicillins ; Viridans Streptococci*