BACKGROUND: Continuous monitoring systems have allowed determination of the time-to-positivity (TTP). We evaluated the clinical relevance of TTP in the BACTEC9240 system (Becton-Dickinson, USA). METHODS: A total of 2,354 vials of positive blood cultures were evaluated over 2 months. TTP was monitored from each of BACTEC Plus Aerobic/F (BD) or Pediatric Plus/F and Lytic Anaerobic/F bottles, and the differential time-to-positivity (DTP) for blood samples drawn simultaneously via catheter and a peripheral site was determined. RESULTS: The average TTP of the positive vials was 17.4 hr, and 79.9% and 95.2% of the vials showed positivity within 24 and 48 hr, respectively. While the average TTP values for Aeromonas hydrophila, Bacillus cereus, Acinetobacter baumannii, and Streptococcus pneumoniae were less than 10 hr, those for Candida spp., anaerobes, Propionibacterium acnes, Corynebacterium spp, Bacillus spp. other than cereus, and coagulase-negative staphylococci were 35.3, 27.0, 56.8, 45.8, 23.0, and 26.3 hr, respectively. The negative predictive values of TTP over 24 hr to predict Staphylococcus aureus among staphylococci and S. pneumoniae among alpha-hemolytic streptococci were 76.7% and 100%, respectively. Enterobacteriaceae and Enterococcus faecalis showed shorter TTP in anaerobic vials than in aerobic vials. DTP of more than 2 hr was observed for 27.8%, 72.2%, and 45.5% of S. aureus, S. epidermidis, and Candida spp. CONCLUSIONS: TTP can be used to discriminate pathogens and contaminants. The shorter TTP in anaerobic vials of certain Enterobacteriaceae and Enterococcus spp. would facilitate further identification. DTP is useful for diagnosing catheter-related bloodstream infection by S. aureus, S. epidermidis, and Candida spp.
Bacteremia/*diagnosis ; Bacteria, Aerobic/isolation &purification ; Bacteria, Anaerobic/isolation &purification ; Bacteriological Techniques/instrumentation/methods ; Humans ; Reagent Kits, Diagnostic ; Time Factors

BACKGROUND: Optimal blood culture performance is critical for successful diagnosis and treatment of sepsis. To understand the status of blood culture, we investigated several aspects of the procedure at 9 university hospitals. METHODS: The process of ordering blood culture sets and sampling volume for adults and children was investigated from January 2010 to April 2010, while the positive rate of detection and growth of skin contaminants were compared in 2009. Microbial growth in aerobic and anaerobic bottles was investigated prospectively. RESULTS: A majority of the hospitals used 2 sets of bottles for adults and 1 bottle for children. The average blood volume in each set was 7.7 mL for adults and 2.1 mL for children. The positive rate of microorganisms was 8.0%, and the isolation rate of the normal flora of the skin was 2.1%. Bacterial growth rates in aerobic and anaerobic bottles only were 31.8% and 24.5% respectively. CONCLUSIONS: Ordering blood culture sets and sampling volumes did not comply with CLSI guidelines. However, the rate of positive cultures and skin contamination rates were acceptable. Anaerobic bottles are useful in enhancing the yield of microorganisms.
Adult ; Bacteremia/blood/*microbiology ; Bacteria, Aerobic/isolation & purification ; Bacteria, Anaerobic/isolation & purification ; Blood/microbiology ; Child ; Hospitals, University ; Humans ; Prospective Studies ; Republic of Korea ; Skin/microbiology

OBJECTIVEThe purpose of this study was to evaluate the effects of squamous cell carcinoma on oral bacteria.

METHODSThis study investigated the microbial contents of the plaque on the surfaces of oral squamous cell carcinomas. Samples were obtained from the central surface of lesions, contiguous healthy mucosa and saliva of 42 patients with oral squamous carcinoma before and after operation.

RESULTSThe median of bacterial colony forming units per milliliter (CFUs/ml) of saliva before operation was 8.10 x 10(8) CFUs/ml. The median of CFUs per square centimeter of the tumor surface was 5.21 x 10(5) CFUs/cm2 which was significantly higher than that of the healthy (the control) mucosa (1.77 x 10(4) CFUs/cm2, P = 0.0001). The CFUs per square centimeter of mucosa surface at the operative zone was 4.34 x 10(5) CFUs/cm2 which was also significantly higher than that of the healthy (control) mucosa(7.24 x 10(4) CFUs/cm2, P = 0.0001).

CONCLUSIONOral carcinoma can break the balance of oral microflora, which may be one of the reasons leading to the high susceptivity of these compromised patients to systemic infection.

Adult ; Aged ; Bacteria, Aerobic ; isolation & purification ; Bacteria, Anaerobic ; isolation & purification ; Bacterial Infections ; etiology ; prevention & control ; Carcinoma, Squamous Cell ; microbiology ; Female ; Humans ; Male ; Middle Aged ; Mouth Mucosa ; microbiology ; Mouth Neoplasms ; microbiology ; Saliva ; microbiology ; Streptococcal Infections ; prevention & control ; Streptococcus ; isolation & purification

Abscess ; diagnosis ; microbiology ; surgery ; Bacteria, Aerobic ; isolation & purification ; Child, Preschool ; Female ; Fever ; Humans ; Prognosis ; Spleen ; pathology ; surgery ; Splenic Diseases ; diagnosis ; surgery ; Treatment Outcome

BACKGROUND/AIMS: The aim of this study was to evaluate the characteristics of cryptogenic and biliary pyogenic liver abscess by comparing the clinical aspects between the two groups. METHODS: Of 119 patients treated for pyogenic liver abscess from 2000 to 2004, 82 subjects with cryptogenic liver abscess and 21 with biliary abscess were analysed retrospectively. RESULTS: There were no significant differences between the two groups regarding clinical symptoms. The characteristics of abscess were similar except the size of abscess. The size of abscess less than 5 cm in diameter was more common in billiary group than in cryptogenic group (p=0.004). Compare to cryptogenic group, biliary group had more positive culture test from abscess (100% vs. 69%, p=0.006). Especially, E. coli isolated from abscess culture (28% vs. 7%, p=0.014) and blood culcure (23% vs. 4%, p=0.035) were more common in biliary group than in cryptogenic group. There was no difference in mortality between the two groups (biliary vs. cryptogenic: 4.8% vs. 0%, p=0.204). However, the rate of clinical improvement was higher in cryptogenic group than in biliary group (92.7% vs. 66.7%, p=0.001). CONCLUSIONS: Biliary liver abscess had similar clinical characteristics to cryptogenic origin. Biliary liver abscess had smaller abscess size and more positive abscess culture rates than cryptogenic abscess. Improvement rate without complication and recurrence was higher in cryptogenic group than biliary group.
Aged ; Biliary Tract Diseases/*diagnosis ; Blood Chemical Analysis ; Female ; Gram-Negative Aerobic Bacteria/isolation & purification ; Gram-Positive Bacteria/isolation & purification ; Humans ; Liver Abscess, Pyogenic/*diagnosis/microbiology ; Male ; Middle Aged ; Retrospective Studies

INTRODUCTIONThe prevalence of diabetes mellitus is high in Singapore. Infections of the lower limb are significant causes of morbidity in this population. Although the aerobic bacteriology of these infections is well-documented, there is less data available on the anaerobic pathogens involved. This study sets out to describe the anaerobic bacteria associated with diabetic foot infections, and evaluates the susceptibility to 3 antimicrobials with anaerobic activity.

MATERIALS AND METHODSAnaerobic culture was performed on operative samples taken from diabetic foot infections. Organisms were identified through standard microbiological methods and commercial identification kits. Antimicrobial susceptibility testing to clindamycin, metronidazole and imipenem was performed by agar dilution.

RESULTSOne hundred and two strains of strict anaerobic bacteria were isolated from 30 unique specimens. The predominant anaerobic isolates were Peptostreptococcus spp. (46%) and Bacteroides fragilis group (19%). Antibiotic resistance was detected for clindamycin (18%), metronidazole (1%) and imipenem (2%).

CONCLUSIONMultiple anaerobic species can be isolated from diabetic foot infections. A significant proportion of isolates are resistant to clindamycin, while resistance to imipenem and metronidazole remains low.

Anti-Bacterial Agents ; therapeutic use ; Bacteria, Aerobic ; drug effects ; genetics ; isolation & purification ; DNA, Bacterial ; analysis ; Diabetic Foot ; surgery ; Drug Resistance, Multiple, Bacterial ; Drug Therapy, Combination ; Humans ; Nucleic Acid Amplification Techniques ; Retrospective Studies ; Surgical Wound Infection ; drug therapy ; microbiology

OBJECTIVE: To investigate the bacterial characteristics of persistent rhinosinusitis after functional endoscopic sinus surgery (FESS). METHOD: Twenty patients with nasal septum deviation, 30 patients with chronic rhinosinusitis (CRS) and 20 patients with persistent rhinosinusitis, were selected to take discharges from middle meatus during the operation. Bacteria culture and drug susceptibility of the discharges were compared between three groups. RESULT: There were 13, 15 and 15 isolates detected in nasal septum deviation group, CRS group and persistent rhinosinusitis group. There was no significant difference among the three groups at the detection rate of Gram-positive bacteria. But there was significant difference between the persistent rhinosinusitis group and the other two groups at the detection rate of Gram-negative bacteria. The detection rate of antibiotic-resistant bacteria were significantly higher in persistent rhinosinusitis group than in CRS group. CONCLUSION Aerobic bacteria can live in nasal cavity. Bacteria infection is one of the etiological factors of persistent rhinosinusitis after FESS. Gram-negative bacteria and antibiotic resistant bacteria are increased in patients with persistent rhinosinusitis. To treat the persistent rhinosinusitis after surgery, the antibiotics should be reasonably used according to the bacteria culture and the drug susceptibility.
Adolescent ; Adult ; Aged ; Bacteria, Aerobic ; isolation & purification ; Bacterial Infections ; microbiology ; Chronic Disease ; Disease Susceptibility ; Endoscopy ; Female ; Humans ; Male ; Middle Aged ; Nasal Cavity ; microbiology ; Postoperative Period ; Sinusitis ; microbiology ; surgery ; Young Adult