Syed Zahid Bukhari, Safia Ahmed, Naheed Zia


Background: The global problem of increasing trend in antimicrobial resistance is particularly pressing
in the developing countries, where the Methicillin-Resistant Staphylococcus aureus (MRSA) is often the
severe casual agent in hospital-acquired infections. Methods: This multi-centre surveillance prospective
study was planned to define the magnitude of problem of MRSA among clinical isolates from four
teaching hospitals of Lahore Pakistan; Mayo, Services, Jinnah and Shaikh Zayed Hospitals during April
2006–March 2008. Identification of organisms was done by the standard Microbiology methods. MRSA
isolates identified on Kirby-Bauer disc diffusion were further evaluated by minimum inhibitory
concentration on BD PhoenixTM system and detection of mecA gene by pulsed-field gel electrophoresis
(PFGE) PCR. Results: Of the total 1,102 S. aureus isolates, oxacillin resistance was found in 462 on disc
diffusion and 420 on MIC while mecA gene was detected from 307 strains. The prevalence of MRSA
among S. aureus isolates was 41.9%, 38.1% and 27.9% on disc diffusion, MIC, and mecA gene
detection respectively. Hospital acquired-MRSA strains were multi drug resistant while community
acquired-MRSA showed susceptibility to clindamycin (63%), ciprofloxacin (24.2%) and SMZ/TMP
(3.9%). In diagnosing MRSA, the sensitivity and specificity rates of disc diffusion test were 100% and
83.7% while MIC 96.2% and 93.3% respectively. Conclusion: There is an increasing trend in
emergence MRSA and the conventional method of antimicrobial susceptibility testing showed false
positive tests. This is the reason of misuse of vancomycin by physicians which may further increase
MRSA in Pakistan. Therefore, molecular diagnostic facilities are recommended to avoid falsesusceptibleresults.
Keywords: S. aureus, MRSA, mecA gene, MIC

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Oliveira CD, Tomaz A, Lencastre H. Secrets of success of a human

pathogen: molecular evolution of pandemic clones of methicillinresistant Staphylococus aureus. Lancet 2002;2:180–89.

Hsu LY, Wijaya L, Tan BH. Management of healthcare-associated

methicillin-resistant Staphylococcus aureus. Expert Rev Anti Infect

Ther 2005;3:893–905.

Zafar A, Stone M, Ibrahim S, Parveen Z, Hasan Z, Khan E, et al.

Prevalent genotypes of meticillin-resistant Staphylococcus aureus:

report from Pakistan. J Med Microbiol 2011;60:56–62.

Francois P, Pittet D, Bento M. Rapid detection of Methicillinresistant Staphylococcus aureus directly from sterile or nonsterile

clinical samples by a new molecular assay. J Clin Microbiol


CLSI. Performance standards for antimicrobial susceptibility

testing. CLSI approved standard M100-S15. Wayen USA: Clinical

and Laboratory Standards Institute; 2007.

Safdar N, Narans L, Gordon B, Maki DG. Comparison of culture

screening methods for detection of nasal carriage of methicillinresistant Staphylococcus aureus: a prospective study comparing

methods. J Clin Microbiol 2003;41:3163–6.

Ashiq B, Tareen AK. Methicillin resistant Staphylococcus aureus

in a teaching hospital of Karachi-a laboratory study. J Pak Med

Assoc 1989;39:6–9.

Qureshi AH, Hannan A. The prevalence and susceptibility pattern

of Methicillin resistant Staphylococcus aureus. Pak J Pathol


Siddique M, Karamat KA, Hannan A. Prevalence of Resistance to

methicillin resistant Staphylococcal aureus (MRSA) A study at

PAF Hospital Sargodha. Pak J Pathol 1999;10:26–9.

Latif S, Anwar MS, Chaudhry NA. The susceptibility pattern of

nosocomial Methicillin resistant Staphylococcus aureus (MRSA)

isolates to vancomycin and other anti-staphylococcal antibiotics.

Biomedical 2000;16:32–5.

Hafiz S, Hafiz AN, Ali L, Chughtai AS. Methicillin resistant

Staphylococcus aureus: A multicentre study. J Pak Med Assoc


Anwar MS, Jaffery G, Bhatti KU, Tayyab M, Bokhari SR.

Staphylococcus aureus and MRSA nasal carriage in general

population. J Coll Physicians Surg Pak 2004;14:661–4.

Bukhari MH, Iqbal A, Khatoon NA. Laboratory study of

susceptibility of methicillin-resistant Staphylococcus aureus

(MRSA). Pak J Med Sci 2004;20:229–33.

Perwaiz S, Barakzi Q, Farooqi BJ, Khursheed N, Sabir N.

Antimicrobial susceptibility pattern of clinical isolates of methicillin

resistant Staphylococcus aureus. J Pak Med Assoc 2007;57:2–4.

Chen Z, Fan X, Lu X. Combination PCR of mecA, femA genes for

detection of MRSA. Sichuan Da Xue Xuc Bao Yi Xue Ban


Krishnan PU, Miles K, Shetty N. Detection of methicillin and

mupirocin resistance in Staphylococcus aureus isolates using

conventional and molecular methods: a descriptive study from a

burns unit with high prevalence of MRSA. J Clin Pathol


Zeeshan M, Jabeen K, Khan E, Irfan S, Ibrahim S, Parween Z,

Zafar A. Comparison of different methods of detection of

methicillin resistance in Staphylococcus aureus with molecular

detection of mecA gene. J Coll Physicians Surg Pak


Geha DJ, Uhl JR, Gustaferrro CA, Persing DH. Multiplex PCR for

identification of methicillin-resistant Staphylococci in the clinical

laboratory. J Clin Microbiol 1994;32:1768–72.

Robert LS, Lars V, Pallesen RL, Poulsen, Espersen F. Evaluation

of a new 3-h hybridization method for detecting the mecA gene in

Staphylococcus ureus and comparison with existing genotypic and

phenotypic susceptibility testing methods. J Antimicrob Chemo


Ojulong J, Mwambu TP, Joloba M, Bwanga F, Kaddu-Mulindwa

DH. Relative prevalence of methicilline resistant Staphylococcus

aureus and its susceptibility pattern in Mulago Hospital, Kampala,

Uganda. Tanzan J Health Res 2009;11(3):149–53.

Nevet A, Ashkenazi S, Samra Z, Livni G. Community-associated

methicillin-resistant Staphylococcus aureus infections in Israel. Isr

Med Assoc J 2010;12:428–30.

Majumder D, Bordoloi JS, Phukan AC, Mahanta J. Antimicrobial

susceptibility pattern among methicillin resistant staphylococcus

isolates in Assam. Indian J Med Microbiol 2001;19:138–40.

Araj GF, Talhoulk RS, Simaan CJ, Maasad MJ. Discrepancies

between mecA PCR and conventional tests used for detection of

methicillin-resistant Staphylococcus aureus. APMIS


Cekovska Z, Panovski N, Petrovska M, Kristof K, Rozgonyi F.

Incidence of Staphylococcus aureus isolated from patients treated

at the Clinical Center of Skopje, Macedonia, with special attention

to MRSA. Acta Microbiol Immunnol Hung 2005;52:373–84.

Sisirak M, Zvizdic A, Hukic M. Methicillin-resistant

Staphylococcus aureus (MRSA) as a cause of nosocomial wound

infections. Bosn J Basic Med Sci 2010;10(1):32–7.

Malik N, Butt T, Arfan-ul-Bari. Frequency and antimicrobial

susceptibility pattern of methicillin resistant Staphylococcus aureus.

J Coll Physicians Surg Pak 2009;19:287–90.

Shrestha B, Pokhrel BM, Mohapatra TM. Antibiotic susceptibility

pattern of nosocomial isolates of Staphylococcus aureus in a tertiary

care hospital, Nepal. J Nepal Med Assoc 2009;48:234–8.

Bukharie HA. Increasing threat of community-acquired methicillinresistant Staphylococcus aureus. Am J Med Sci 2010;340:378–81.

Cataldo MA, Taglietti F, Petrosillo N. Methicillin-resistant

Staphylococcus aureus: a community health threat. Postgrad Med


Marchese A, Gualco L, Maioli E, Debbia E. Molecular analysis and

susceptibility patterns of meticillin-resistant Staphylococcus aureus

(MRSA) strains circulating in the community in the Ligurian area, a

northern region of Italy: emergence of USA300 and EMRSA-15

clones. Int J Antimicrob Agents 2009;34(5):424–8.


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