D-Test method for detection of inducible clindamycin resistance in staphylococcus aureus

Methicillin resistant staphylococcus aureus [MRSA] is a frequent cause of infections in children. The purpose of this study was to determine the frequency of nasal colonization of S. aureus in children and detection of inducible clindamycin resistance [ICR] by disk approximation test [D-test]. This was a cross-sectional study conducted in Hamedan from 2007 to 2008. 520 nasal swabs were obtained from children under 12 years of age at the time of admission and 287 swabs at the time of discharge. Antibiogram was performed by method of disk diffusion for oxacillin, erythromycin, clindamycin, cefazolin and vancomycin as well as D-test. Chi-square test was applied for statistical analysis. Out of 520 patients, 118 [22.3%] were colonized with S. aureus as community-acquired [CA-S. aureus]. Of 287 patients, 64 [22.3%] were colonized with isolates of S. aureus at discharge time. Of these 64 patients, 32 cases were colonized with hospital acquired [HA-S. aureus] isolates after admission. Only one CA-MRSA isolate was resistant to clindamycin, 5% of 118 CA-S. aureus isolates and 6.3% of HA-S. aureus isolates had inducible clindamycin resistance [D-test]. Also 37.5% of CA-MRSA isolates at the time of admission and 22.2% of HA-MRSA isolates at discharge had positive D-test. We emphasize that D-test should be used routinely and clindamycin should not be used in patients with infections caused by inducible resistant S. aureus

Typing of the uropathogenic E. coli strains using O-serotyping and detection of pap adhesion-encoding operon by polymerase chain reaction

Urinary tract infection [UTI] is a frequently diagnosed renal and urologic disease. Escherichia coli is by far the most common etiologic agent of this disease. This study was aimed to type the E. coli strains isolated from the patients with urinary tract infection using sero-grouping Detection of pap adhesion-encoding operon was also targeted. A total of 130 E. coli strains isolated from patients with UTI were investigated for O-serotyping. The presence of pap adhesion-encoding operon was detected using polymerase chain reaction [PCR]. In serogrouping with 13 antisera, 86 strains [66.14%] were O-serogroupable and belonging to O1, O6, O15, O18 and O20 serogroups, while 44 strains [33.86%] were O-non typeable. Predominant serogroups were O6 and O18. The PCR results showed that 61% of strains exhibited the pap genotype. Serogroups O1, O6, O15 and O18 possessed pap operon. There was an obvious correlation between the pap operon and the O-serogroups of the strains. Our results showed that obtained protein patterns of the isolated strains were more reliable than serotyping results for typing purposes. Our findings indicated that pap adhesion-encoding operon has an important role in the development and severity of UTI. Many cases of serious urogenital diseases are caused by a limited number of uropathogenic E. coli strains that generally possess special virulence factors such as pap operon

[ frequency of prevotella species in women with bacterial vaginosis and detection of the drug resistance]

Recently drug resistance to three species of Prevatella [P.bivia, P. melaninogemcus, P. disicns] is seen. The aim of this study was to evaluate the frequency of bacterial vaginosis and detection of drugs resistance of Prevotella species. This descriptive study performed from 2004 to 2005 at Fatemi Hospital of Hamadan, Iran, on 310 female patients with vaginal discharge. This study was approved by the local committee of medical ethics. Laboratory diagnosis of bacterial vaginosis was based on 4 criteria including study of the homogenesity of the discharges, performing of whiff test, search for clue cell in smear and determination of pH of the discharge. Antibiogram test was performed by method of Kirby-Bauer and 9 commonly used antibiotics were applied. The data collected in a questionnaire and analyzed, using SPSS software. Of 310 patients with discharge, 65.7% were diagnosed as bacterial vaginosis that 47.4% of them had clue cells, 66.2% were whiff test positive, pH of 87.1% of the discharge were more than 4.5 and 76.7% had non-homogenous discharge. Out of 310 samples, 60 [19.3%] Prevotella species isolated in which 80% was P.bivia, 11.6% P.disiens and 8.3% Pjnelaninogenicus. These isolates and 4 references strains were resistant to penicillin [100%] and to vancomycin, kanamycin [> 60%]. Resistance to eefoxcetin, clindamycin, metronidazole and ciprofloxacin were less than 10%. The frequency of bacterial vaginosis in our patients was relatively high. The most frequent isolated strain was P.bivia and also the most effective antibiotics against Prevotella isolates were ciprofloxacin, cefoxcetin, clindamycin and metronidazole

epidemiology of burn wound infections in patients hospitalized in burn center of Hamedan, Western Iran

A total of 465 burned patients with wound infections who admitted to referral burns center of Hamedan Imam Khomeiny hospital from July 1998 to June 2001 were retrospectively studied. The required data including age, sex, season, causes of burns, burn size of wounds and types of organisms isolated from patients [wounds and blood], was recorded in a questionnaire. The susceptibility of the isolates to eight routine antibiotics was tested by disc diffusion method.The data was analyzed by SPSS and EP16 software package. Out of 465 burn wound infections 73.1% of isolates were Gram-negative bacilli and 26.9% were Gram-positive cocci. Pseudomonas aeruginosa [32.7%], Klebsiella pneumoniae [21.8%] and Staphylococcus aureus [21.2%] were the most common isolates. In 28.7% of patients, blood culture became positive, Klebsiella pneumoniae [30.4%], Pseudomonas aeruginosa [26.9%], were predominant isolates. 57.3% of patients were males and the most frequency of burn patients belonged to age group 0-9 years old [28.6%], most of the burns occurred during summer. Boiled water, fuel oil flames and firewood flames were the commonest causative agent for burns, respectively. The most effective antibiotics against isolates were ciprofloxacin, ceftizoxime, amikacin and gentamicin, while most of isolates showed high resistance to ampicillin, tetracycline and carbenicillin. Present results indicated that Pseudomonas aeruginosa, Klebsiella pneumoniae and Staphylococcus aureus were predominant isolates with high resistance to tested antibiotics. These data can be used to evaluate the effects of changes in burn treatment and antimicrobial resistance development in relation to antibiotic usage