title: Changing patterns of drug-resistant Shigella isolates in egypt.
abstract: BACKGROUND
  The emergence of multidrug resistance (MDR) is a serious problem in treating shigellosis. There are limited existing data examining the change in the antimicrobial resistance profile of Shigella in Egypt. We previously reported that 58% of the Shigella isolates in Egypt were resistant to at least one member of the three different antimicrobial groups. This study was performed to determine the antimicrobial resistance profile of Shigella, determine their possible mechanisms of resistance, and compare their resistance profile to those reported 20 years ago.
  
  
  METHODS
  Stool samples were collected from 500 subjects and processed for the isolation and identification of Shigella. The susceptibility of the isolates to 11 different antimicrobials was determined using the disc diffusion method.
  
  
  RESULTS
  Of 500 stool cultures, 24 (4.8%) samples were positive for Shigella. There was a high percentage of resistance to ampicillin (88%), tetracycline (83%), and sulfamethoxazole-trimethoprim (75%). Also, there was a moderate percentage of resistance to chloramphenicol (46%), streptomycin (42%), ceftazidime (33%), and cefotaxime (25%). A lower percentage of resistance was recorded for amikacin, nalidixic acid (17% each), and ofloxacin (7%), while no resistance was found to ciprofloxacin (0%). Twenty-one of the isolates (88%) were resistant to at least three different antimicrobial groups (indicating MDR). The average number of antimicrobial agents to which the Shigella isolates were resistant was 4.3±1.4, while it was 3.4±1.5 in the same locality in 1994.
  
  
  CONCLUSIONS
  These data demonstrate that there is a marked increase in MDR and change in the resistance patterns of Shigella over the past 20 years.
authors.affiliation: 1Department of Microbiology and Immunology, Faculty of Medicine, Minia University, Minia, Egypt.|2Minia Regional Blood Bank, Minia, Egypt.
authors.forename: Ghada M
authors.initials: GM
authors.lastname: Abd-Elmeged
authors.affiliation: 1Department of Microbiology and Immunology, Faculty of Medicine, Minia University, Minia, Egypt.
authors.forename: Rasha M
authors.initials: RM
authors.lastname: Khairy
authors.affiliation: 1Department of Microbiology and Immunology, Faculty of Medicine, Minia University, Minia, Egypt.
authors.forename: Sahar M
authors.initials: SM
authors.lastname: Abo-Eloyoon
authors.affiliation: 1Department of Microbiology and Immunology, Faculty of Medicine, Minia University, Minia, Egypt.|3Faculty of Pharmacy, Taif University, Taif, Kingdom of Saudi Arabia.
authors.forename: Sayed F
authors.initials: SF
authors.lastname: Abdelwahab
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000617:Aminoglycosides / Q000494:pharmacology; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D002701:Chloramphenicol / Q000494:pharmacology; D052978:Disk Diffusion Antimicrobial Tests; D024901:Drug Resistance, Multiple, Bacterial; D004405:Dysentery, Bacillary / Q000188:drug therapy* / Q000453:epidemiology* / Q000382:microbiology; D004534:Egypt / Q000453:epidemiology; D005243:Feces / Q000382:microbiology; D005260:Female; D006801:Humans; D015994:Incidence; D007223:Infant; D008297:Male; D008875:Middle Aged; D011804:Quinolines / Q000494:pharmacology; D012760:Shigella / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D013754:Tetracyclines / Q000494:pharmacology; D015662:Trimethoprim, Sulfamethoxazole Drug Combination / Q000494:pharmacology; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D011804:Quinolines; D013754:Tetracyclines; D047090:beta-Lactams; D002701:Chloramphenicol; D015662:Trimethoprim, Sulfamethoxazole Drug Combination