MULTIDRUG RESISTANT MYCOBACTERIUM TUBERCULOSIS IN ADAMAWA STATE, NIGERIA.

BACKGROUND: There is a need to have regular updates from regions where high burden of tuberculosis (TB) have been reported in order to assist the local and global bodies in their objective to curtail the spread of drug resistant TB (DRTB). This study presents a situation report of DRTB in Adamawa State which has been identified as one of the States with high burden of TB in Nigeria. MATERIALS AND METHODS: Sputum culture in Lowenstein-Jensen Media, drug sensitivity tests and the GeneXpert MTB/Rif analysis were used in the identification and drug susceptibility studies of M. tuberculosis isolates obtained from forty TB patients who were enrolled from three selected hospitals with DOTS facilities in the State. RESULTS: The age of TB patients range from 17 to 70 years (median = 30 years). Twenty (50 %) M. tuberculosis isolates were detected by the GeneXpertMTB/Rif analysis while the media culture detected 31 (77.5%). The two methods however detected rifampicin resistance in 4 (10%) of the total isolates. All rifampicin resistant isolates were multidrug resistant TB (MDRTB) and three of them were from male patients aged 30, 38 and 45. There was only one case of resistance to streptomycin, 3 to ethambutol and 6 to isoniazid. Monoresistance were only observed for ethambutol and isoniazid and it was found in two isolates for each. CONCLUSION: There is a need to provide interventions to control MDRTB in the state and to make such interventions available and closer to the patients.

The pathogenicity of Staphylococcus epidermidis on the intestinal organs of rats and mice: an experimental investigation.

BACKGROUND: Staphylococcus epidermidis is the most frequently isolated species of the coagulase negative staphylococci from human stool. However, it is not clear how its presence in the gut affects the cellular structures and functions of this organ. In this study therefore, the pathogenicity of strains of S. epidermidis which were isolated from the stool samples of apparently healthy children was investigated in mice and rats. METHODS: The albino mice (22-30 g) and albino rats (100-155 g) of both sexes were infected orally and intraperitoneally with graded doses of the bacteria and subjected to behavioral and histopathological examinations. RESULTS: Acute infection in these animals caused temporary behavioural changes as shown by restlessness and abdominal stretchings but did not result in death even at a dosage of 2 × 109 cfu/kg. Daily administration of the same dose for 14 days resulted in the death of 11 out of 21 (52.4%) mice. Histopathological examination of the affected organs showed congestions, aggregations and multinucleated hepatocytes in the liver, infiltration of the kidney tubule interstitial by chronic inflammatory cells, coagulative necrosis of the kidney, spleen, intestine and stomach cells as well as marked stroma fibrosis of the spleen. Coagulative necrosis of cells was the most frequently occurring pathological alteration. Lethality and pathological effects reflected the virulence factors expressed by the organism which are biofilm formation, haemagglutination properties and capsule production. CONCLUSIONS: The results indicate that strains of S. epidermidis colonising the gut can cause serious pathological changes on certain organs such as kidney, liver, intestine, stomach and spleen which, depending on their severity, could be fatal.

Diversity of antibiotic resistance genes and staphylococcal cassette chromosome mec elements in faecal isolates of coagulase-negative staphylococci from Nigeria.

BACKGROUND: Coagulase-negative staphylococci (CoNS) are opportunistic pathogens found as colonisers of the human gut. This study was carried out to examine the genetic resistance mechanisms in faecal isolates of CoNS. The study investigated 53 non-duplicate CoNS isolates obtained from the fresh stool samples of apparently healthy subjects in the community of Ile-Ife, South-Western Nigeria. Antibiotic susceptibility testing was assessed by the disc diffusion test while antibiotic resistance genes were analysed by PCR. mecA positive isolates were analysed by Staphylococcal Chromosome Cassette mec (SCCmec) and cassette chromosome recombinase (ccr) complex typing methods. RESULTS: Resistance genes were detected only in isolates that showed resistance by phenotypic screening. The aac(6')-aph(2") gene was detected in all the three isolates resistant to gentamicin. Four of the five erythromycin resistant isolates were positive for the ermC gene, the remaining isolate carried the msrA gene. The tetK gene was detected in 6 of the 7 tetracycline resistant isolates while 4 possessed the tetM gene. Three of the isolates (S. haemolyticus, S. xylosus and S. capitis) had both genes. Several SCCmec types were found: SCCmec I- ccrABß2-α2 (4 isolates: 3 S. epidermidis, 1 S. warneri), SCCmecIVb- ccrABß2-α3 (1 isolate: S. epidermidis), SCCmecIVd- ccrABß2-α3 (8 isolates: 3 S. epidermidis, 2 S. xylosus, 1 S. saprophyticus, 1 S. warneri, 1 S. capitis), and untypable (2 isolates: S. epidermidis). CONCLUSION: This genetic background could be a reservoir for interspecies gene transfer among CoNS and S. aureus in the intestinal tract.

Pattern of pathogens from surgical wound infections in a Nigerian hospital and their antimicrobial susceptibility profiles.

BACKGROUND: In surgical patients, infection is an important cause of morbidity and mortality. A prospective study to find the pattern of microorganisms responsible for post operative wound infections and their antibiotic susceptibility profile was therefore conducted. SETTING AND METHODS: Surgical wards in Obafemi Awolowo University Teaching Hospital Complex, Ile-Ife, Nigeria. Isolation, identification and antimicrobial susceptibility screening of organisms were done employing standard microbiological techniques. RESULTS: Bacterial pathogens were isolated from all the specimens while the yeast Candida species (spp) was isolated from 12.4%. Staphylococcus aureus was the most frequent organism isolated accounting for 23 (18.3%) of a total of 126 isolates. Other organisms were Pseudomonas aeruginosa and Bacillus spp 11.1% each; Escherichia coli 10.3%; Candida spp 8.7%; Coagulase negative staphylococci 8.7%; Pseudomonas spp 6.3%; Serratia odorifera 4.7%; Bacteroides 4.0%; Enterococcus spp 3.2%; the remaining isolates were other enterobacteria. Sensitivity of the bacterial isolates to antibiotics varied. In general, resistance to the ß-lactam antibiotics was above 98%, whilst more than 70% of isolates were resistant to erythromycin, fusidic acid and tobramycin. CONCLUSIONS: The infections were polymicrobic and multidrug resistant. The quinolones, ciprofloxacin and ofloxacin, should be used as frontline drugs in the management of surgical wound infections at the hospital.

Susceptibility of community associated methicillin resistant Staphylococcus aureus isolated from faeces to antiseptics.

INTRODUCTION: The study aimed to investigate the resistance of methicillin resistant Staphylococcus aureus (MRSA), an indicator used in hospitals but isolated from faecal samples of children in the community, to commonly used antibiotics and antiseptic agents. METHODOLOGY: S. aureus isolates were identified by phenotypic and genotypic techniques such as biochemical tests and polymerase chain reaction. Antibiotic susceptibility was investigated using the disc diffusion technique while the agar dilution method was used to determine the minimum inhibitory concentration (MIC) of antiseptics. RESULTS: MRSA showed considerably higher resistance to other antibiotics than methicillin sensitive Staphylococcus aureus (MSSA). Twelve percent of the MSSA were susceptible to all the antibiotics studied while none of the MRSA had this property. A significant difference in susceptibility between MRSA and MSSA to the three antiseptic agents was observed as 68.8%, 75.0% and 100% of MRSA were less susceptible to benzalkonium chloride, chlorhexidine and cetrimide respectively, while 32.0%, 28.0% and 56.0% of MSSA respectively were less susceptible to these agents compared with S. aureus NCTC 6571. Overall, the MICs for the antiseptics were 2-3 times greater in the MRSA than in the MSSA (p < 0.001). CONCLUSION: Results show that the concentration of antiseptics used in the prevention of the transmission of infectious agents may have to be raised to cope with the possible presence of MRSA in patients coming into hospital.