Molecular identification of methicillin-resistant staphylococcus aureus in Khartoum teaching hospital

Antimicrobial resistance has become a great public health problem worldwide and multi-drug resistant Staphylococcus aureus has been widely reported. The presence or absence of methicillin resistance gene [mecA] in 48 clinical wound isolates of S. aureus was examined by the polymerase chain reaction [PCR]. The results were analyzed in parallel to the disk diffusion method by oxacillin [1 microg]. Polymerase chain reaction was amplified at a sequence of mecA gene at 1319 bp. Nine [18.75%] out of the 48 isolates and were found to be identical to those of disk diffusion test. All strains were studied for their susceptibility to traditionally used antibiotics. The results revealed that multi-drug resistance was common among MRSA strains. The drug of choice for the treatment of MRSA and MSSA was vancomycin. The study concluded that multiple antibiotic resistance was common, and the PCR assay can be used to confirm MRSA infection

use of antibiotics as food additives in poultry and their effect on antibiotic resistance

The widespread use and misuse of antimicrobials beyond human medicine, assisted in the alarming emergence of resistance amongst the bacterial strains. to determine the effect of the use of antibiotics as food additives on the intestinal flora of poultry. one hundred and eighty chickens at the age of two weeks were divided equally into six groups. Five of these groups were used for the test and the sixth served as a control group. Each of the test groups was fed with a different type of antibiotic which served as food additives. The control group was fed an antibiotic-free diet. The antibiotics used were amoxycillin, ciprofloxacin, tetracycline, gentamicin and co-trimoxazole. Rectal swabs were collected from the chickens at the age of two and six weeks respectively. The specimens were processed for the isolation and antibiotic sensitivity of E. coli from each group. After slaughtering the chickens, the presence of the antibiotic residue in the tissues was tested. Pieces of tissues were applied on a sensitivity agar using standard E coli as a test organism. significant increase in antibiotic resistance was noticed in the test groups [P < 0.05]. The change in resistance was insignificant in the control group [P > 0.05]. The pieces of tissues from the test groups inhibited the growth of E coli indicating the presence of antibiotic residue. No inhibition of growth was detected in the control group. The use of antibiotics as food additives in animals and poultry can lead to the emergence of resistant bacterial strains in their intestinal flora and can leave antibiotic residue in their tissue

Antibiotic susceptibility and plasmid profiles of shigella species in Sudan

This study was carried out to determine the antibiotic susceptibility, plasmid profile and conjugative abilities of Shigella species isolated from different towns in Sudan during 2005-2007. Stool specimens were collected in Carry Blair transport medium from patients presenting with diarrhea from different sites in Sudan between the years 2005-2007. All specimens were inoculated on Mac Conkey' s agar and Xylose Lysine Dioxycholate [XLD] [Mast group Ltd. Merseyside UK]. Bacteria was isolated and subjected to different antibiotics to detect sensitivity and transference of resistance. One hundred and fourteen Shigella isolates were included in the study. Eighty [70.1%] were Shigella flexeneri representing the dominant isolate, followed by 20 [17.5%] isolates of Shigella dysenteriae, 9 [7.9%] Shigella sonnei and 5 [4.5%] Shigella boydii. Most of the isolates showed resistance to streptomycin [70%], tetracycline [52%] and co-trimoxazole [43%]. They were highly sensitive to norfioxacin [97%], nalidixic acid [95%], gentamicin [89%] and chloramphenicol [77%]. Multi-drug resistance to two or more antibiotics was apparent in most of the isolates [64, 56.1%]. Fifty nine of the resistant Shigella isolates were studied for their ability to transfer resistance to the donor E. coli K[12] by conjugation. Of these, six were able to transfer resistance to streptomycin, tetracycline and co-trimoxazole. Extraction of the plasmid DNA from both donors and trans-conjugants showed a single type of plasmid with a molecular weight of 4.6 Kb. The transfer of multi-drug resistant plasmids and the emergence of antibiotic Shigella and other bacterial species should raise the awareness and the seriousness of the uncontrolled [unsupervised] use of antibiotics in the medical practice