Methicillin-resistant coagulase-negative staphylococci from healthy dogs in Nsukka, Nigeria

The occurrence, resistance phenotype and molecular mechanisms of resistance of methicillin-resistant staphylococci from groin swabs of 109 clinically healthy dogs in Nsukka, Nigeria were investigated. The groin swab samples were cultured on mannitol salt agar supplemented with 10 µgof cloxacillin. Sixteen methicillin-resistant coagulase negative staphylococci (MRCoNS), all harbouring the mecA gene were isolated from 14 (12.8%) of the 109 dogs studied. The MRCoNS isolated were: S. sciuri subspecies rodentium, S. lentus, S. haemolyticus, and S. simulans with S. sciuri subspecies rodentium (62.5%) being the predominant species. Thirteen (81.3%) of the MRCoNS were resistant to tetracycline while 12 (75%) and 10 (62.5%) were resistant to kanamycin and trimthoprim-sulphamethoxazole respectively. None of the isolates was resistant to fusidic acid, linezolid and vancomycin. Thirteen (81.3%) of the MRCoNS were multi-drug resistance (MDR). Other antimicrobial genes detected were: blaZ, tet(K), tet(M), tet(L), erm(B), lnu(A), aacA-aphD, aphA3, str, dfr(G), cat pC221,and cat pC223. Methicillin-resistant staphylococci are common colonizers of healthy dogs in Nigeria with a major species detected being S. sciuri subsp. rodentium.

Rapid detection of methicillin-resistant staphylococcus aureus [MRSA] in nose, groin, and axilla swabs by the BD GeneOhm MRSA achromopeptidase assay and comparison with culture

To compare the BD GeneOhm Methicillin Resistant Staphylococcus aureus [MRSA] Achromopeptidase [ACP] polymerase chain reaction [PCR] assay with the culture method for the detection of MRSA colonization. One hundred and two patients were admitted to the Intensive Care Unit in King Khalid Hospital, Najran, Kingdom of Saudi Arabia from July 2010 to February 2011. Separate swabs from the nose, axilla, and groin of each patient were processed by the culture method [sheep blood agar plate and mannitol salt agar plate] and BD GeneOhm MRSA ACP assay. Of the 287 samples, 62 [21.6%] were MRSA positive by the PCR assay and 26 [9%] were MRSA positive by the culture method. The PCR method showed 88.4% sensitivity and 98.6% negative predictive value. The number of MRSA-PCR positive groin specimens was nearly the same as nasal specimens. The PCR method gave positive results in 22.5% of patients by nasal specimens, 27.5% of patients by nasal and groin specimens, and 30.4% of patients by nasal, groin, and axilla specimens. The PCR method detected 30.4% of patients as MRSA positive while the culture method detected 19.6% of patients as positive for MRSA. The BD GeneOhm MRSA ACP assay has high sensitivity and NPV and hence is a useful screening method to exclude patients who are not colonized with MRSA