Antimicrobial susceptibility of bacteria isolated from cerebrospinal fluids in an Iranian referral pediatric center, 1998-2008.

Antimicrobial susceptibility patterns of bacterial meningitis provide essential information regarding selection of antibiotic therapy for patients with bacterial meningitis. This study presents data on causes of bacterial meningitis and their susceptibility pattern among children at Children's Medical Center (CMC), a referral tertiary care center in Iran. In this comprehensive retrospective study we reviewed microbiology records of all inpatients suspected to bacterial meningitis, during 1998-2008 of period. Of 11269 CSF cultures examined in the study, 329 (2.9%) were positive for bacterial growth. Overall, coagulase negative staphylococci (CONS) were the most frequent group of organism recovered from our CSF cultures (40%), followed by gram negative enteric bacilli (19.7%). Also, high rates of oxacillin and vancomycin resistance were found among staphylococci. In our study more than 80% of gram-negative enteric bacteria were resistant to ampicillin; we also found high rates of cephalosporin resistance among these organisms. Over 55% of S. pneumoniae were resistant to penicillin. Staphylococci species and gram-negative enteric organisms were the most common pathogens isolated from CSF cultures in this study. It seems that nosocomial meningitis is the main cause of bacterial meningitis in CMC Hospital. Our report draws attention to the importance devising a national strategy to control the spread of resistance in Iran.

Evaluation of procalcitonin and neopterin level in serum of patients with acute bacterial infection.

BACKGROUND: Fever as a common presenting complaint in pediatric patients can be due to various causes. Differentiating bacterial infection from other causes is important because the prompt use of antibiotics is critical in bacterial infection. Traditional markers of infection such as BT and WBC count may be unspecific and culture may be late or absent. CRP and Procalcitonin (PCT) have been considered to evaluate the evolution of infections and sepsis in patients presenting with SIRS. Neopterin has also been proposed to aid in the diagnosis of bacterial infection. In this study, we compared the value of the serum PCT, neopterin level, and WBC count for predicting bacterial infection and outcome in children with fever. METHODS: 158 pediatric (2-120-month-old) patients suspected to have acute bacterial infection, based on clinical judgment in which other causes of SIRS were ruled out were included in the study. WBC count with differential was determined and PCT and neopterin levels were measured. RESULTS: PCT level was higher in bacterial infection and patients who were complicated or expired. CONCLUSION: Rapid PCT test is superior to neopterin and WBC count for anticipating bacterial infection, especially in ED where prompt decision making is critical.

Frequency and antimicrobial susceptibility of Shigella species isolated in Children Medical Center Hospital, Tehran, Iran, 2001-2006.

Appropriate antimicrobial treatment of shigellosis depends on identifying its changing resistance pattern over time. We evaluated 15,255 stool culture submitted from July 2001 to June 2006 to the Laboratory of Children Medical Center Hospital. Specimen culture, bacterial identification, and disk diffusion susceptibility testing were performed according to National Committee for Clinical Laboratory Standards guidelines. From 15,255 stool samples, 682 (4.5%) were positive for Shigella species. The most common species of Shigella were S. flexneri (48%) and S. sonnei (45%); other results were S. dysenteriae (5%) and S. boydii (2%). The rate of sensitivity to ceftriaxone (95%), ceftizoxime (94%), and nalidixic acid (84%) were among our isolates. Resistance to co-trimoxazole and ampicillin was 87% and 86%, respectively. S. flexneri was more multiresistant than other species (47.9%). Our isolates are overall most sensitive to ceftriaxone, ceftazidime, and nalidixic acid (> 84%). They were most resistant to co-trimoxazole and ampicillin (> 86%). Because resistance varies according to specific location, continuous local monitoring of resistance patterns is necessary for the appropriate selection of empirical antimicrobial therapy.

Evaluation of procalcitonin and neopterin level in serum of patients with acute bacterial infection

BACKGROUND: Fever as a common presenting complaint in pediatric patients can be due to various causes. Differentiating bacterial infection from other causes is important because the prompt use of antibiotics is critical in bacterial infection. Traditional markers of infection such as BT and WBC count may be unspecific and culture may be late or absent. CRP and Procalcitonin (PCT) have been considered to evaluate the evolution of infections and sepsis in patients presenting with SIRS. Neopterin has also been proposed to aid in the diagnosis of bacterial infection. In this study, we compared the value of the serum PCT, neopterin level, and WBC count for predicting bacterial infection and outcome in children with fever. METHODS: 158 pediatric (2-120-month-old) patients suspected to have acute bacterial infection, based on clinical judgment in which other causes of SIRS were ruled out were included in the study. WBC count with differential was determined and PCT and neopterin levels were measured. RESULTS: PCT level was higher in bacterial infection and patients who were complicated or expired. CONCLUSION: Rapid PCT test is superior to neopterin and WBC count for anticipating bacterial infection, especially in ED where prompt decision making is critical. ABBREVIATIONS: BT, body temperature; WBC, white blood cell; PCT, procalcitonin; CRP, C-reactive protein; SIRS, systemic inflammatory response syndrome; ED, emergency department.

Frequency and antimicrobial susceptibility of Shigella species isolated in Children Medical Center Hospital, Tehran, Iran, 2001-2006

Appropriate antimicrobial treatment of shigellosis depends on identifying its changing resistance pattern over time. We evaluated 15,255 stool culture submitted from July 2001 to June 2006 to the Laboratory of Children Medical Center Hospital. Specimen culture, bacterial identification, and disk diffusion susceptibility testing were performed according to National Committee for Clinical Laboratory Standards guidelines. From 15,255 stool samples, 682 (4.5 percent) were positive for Shigella species. The most common species of Shigella were S. flexneri (48 percent) and S. sonnei (45 percent); other results were S. dysenteriae (5 percent) and S. boydii (2 percent). The rate of Sensitivity to ceftriaxone (95 percent), ceftizoxime (94 percent), and nalidixic acid (84 percent) were among our isolates. Resistance to co-trimoxazole and ampicillin was 87 percent and 86 percent, respectively. S. flexneri was more multiresistant than other species (47.9 percent). Our isolates are overall most sensitive to ceftriaxone, ceftazidime, and nalidixic acid (> 84 percent). They were most resistant to co-trimoxazole and ampicillin (> 86 percent). Because resistance varies according to specific location, continuous local monitoring of resistance patterns is necessary for the appropriate selection of empirical antimicrobial therapy.

Frequency of isolation and antimicrobial susceptibility of bacteria isolated from bloodstream infections at Children's Medical Center, Tehran, Iran, 1996-2000.

Antimicrobial susceptibility patterns of major bloodstream pathogens from Iran provide essential information regarding the selection of antibiotic therapy for patients with bloodstream infections (BSIs) living in Iran. Unfortunately, data regarding the isolation frequency and antimicrobial susceptibility patterns of endemic BSI pathogens are scarce in Iran. To shed some light on the susceptibility patterns of BSI pathogens endemic to Tehran, Iran, we investigated the antimicrobial susceptibility patterns of 2248 bloodstream isolates from patients in Children's Medical Center (CMC) Hospital in Tehran between January 1996 and December 2000. Microbiology reports of 24600 blood specimens collected from inpatients in CMC Hospital were retrospectively reviewed. Specimen culture, bacterial identification and disk diffusion susceptibility testing were performed according to National Committee for Clinical Laboratory Standards guidelines. Overall, Gram-positive bacteria comprised 72% (1627/2248) of recovered isolates and Gram-negative bacteria comprised 28% (621/2248). Coagulase-negative staphylococci (CoNS) comprised 48.4% of all isolates, followed by Staphylococcus aureus (16.7%) and Klebsiella spp. (8.5%). Among the 621 Gram-negative organisms, Klebsiella spp. (31%) were the most frequently isolated, followed by Escherichia coli (21%) and Pseudomonas aeruginosa (17%). The rates of oxacillin resistance for S. aureus and CoNS isolates were similar (60% versus 61%); however, the rate of S. aureus vancomycin resistance was almost twice that of CoNS resistance (21% versus 11%). Over 55% of S. pneumoniae were resistant to penicillin and co-trimoxazole. Although all isolates of enterococci were susceptible to vancomycin, only 21% were susceptible to gentamicin. Among Gram-negative isolates, amikacin was shown to be very effective, with susceptibility rates of 84%. The susceptibility of Klebsiella spp. to ampicillin and co-trimoxazole was 1% and 39%, respectively. The susceptibility of Klebsiella spp., E. coli and Enterobacter spp. to ceftriaxone was 47%, 86% and 67%, respectively. There were notable differences in the order of the five most common organisms isolated from blood cultures, which can help set priorities for focused control efforts. Our findings highlight the importance of a nationwide surveillance programme to monitor the trends in isolation frequency of bacteria and their antimicrobial resistance patterns throughout Iran.