Antibacterial resistance and molecular typing of methicillin-resistant Staphylococcus aureus in a Kuwaiti general hospital

Molecular Characterization of Methicillin- Resistant Staphylococcus aureus in a Tertiary Care hospital in Kuwait

Methicillin-resistant Staphylococcus aureus (MRSA) are a major cause of healthcare and community- associated infections due to their ability to express a variety of virulence factors. We investigated 209 MRSA isolates obtained from 1 January to 31 December 2016 using a combination of phenotypic and genotypic methods to understand the genetic backgrounds of MRSA strains obtained in a General hospital in Kuwait. Antibiotics susceptibility was performed with disk diffusion, and MIC was measured with Etest strips. Molecular typing was performed using SCCmec typing, spa typing, and DNA microarray for antibiotic resistance and virulence genes. The isolates were susceptible to vancomycin, teicoplanin, rifampicin, ceftaroline, and linezolid but were resistant to gentamicin, tetracycline, erythromycin, fusidic acid, chloramphenicol and ciprofloxacin. Molecular typing revealed six SCCmec types, 56 spa types and 16 clonal complexes (CC). The common SCCmec types were type IV (39.5%), type III (34.4%), type V (25.8%) and type VI (3.8%). The dominant spa types were t860 (23.9%), t945 (8.6%), t127 (6.7%), t688 (6.7%), t304 (6.2) and t044 (5.7%). The other spa types occurred sporadically. Genes for PVL was detected in 59 (28.2%) of the isolates. CC8-ST239-MRSA-III + SCCmer (23.3%) was the most prevalent clone, followed by CC6-MRSA-IV (8.3%), CC80-MRSA-IV [PVL+] (5.8%), CC5-MRSA-VI + SCCfus (5.0%), CC30-MRSA-IV[PVL+] (4.1%), CC1-MRSA-V + SCCfus [PVL+] (4.1%), CC5-MRSA-V + SCCfus (4.1%) and CC22-MRSA-IV[PVL+] (4.1%). The study revealed that despite the emergence of MRSA with diverse genetic backgrounds over the years, ST239-MRSA-III remained the dominant clone in the hospital. This warrants reassessment of infection prevention and control procedures at this hospital.

Infectious diseases in the Arabian Peninsula and Egypt

Infectious diseases are important causes of morbidity and mortality globally. Epidemiologically, differences in the patterns of infectious diseases and antimicrobial resistance exist across diverse geographical regions. In this review on infectious diseases in the Arabian Peninsula and Egypt, the epidemiology of tuberculosis, malaria and human immunodeficiency virus (HIV) infections will be addressed. The challenges of the hepatitis C epidemic in Egypt and the epidemiology of this infection across the region will be reviewed. In recent years, we have seen dengue endemicity become established, with major outbreaks in parts of the region. Emerging data also indicate that, across the region, there is an increasing burden of antibiotic resistance, with endemicity in healthcare settings and dissemination into the community. New challenges include the emergence of the Alkhurma haemorrhagic fever virus in Saudi Arabia. The annual Hajj pilgrimage in Saudi Arabia serves as a model for the control of infectious disease in mass gatherings. As most of these countries constantly experience a uniquely dynamic population influx in the form of expatriate workers, tourists, or pilgrims, concerted regional and international collaboration to address these public health concerns in a region that lies at the crossroads for the global spread of infectious pathogens is imperative.

Predominance and emergence of clones of hospital-acquired methicillin-resistant Staphylococcus aureus in Malaysia

We define the epidemiology of predominant and sporadic methicillin-resistant Staphylococcus aureus (MRSA) strains in a central teaching and referral hospital in Kuala Lumpur, Malaysia. This is done on the basis of spa sequencing, multilocus sequence typing (MLST), staphylococcal cassette chromosome mec (SCCmec) typing, and virulence gene profiling. During the period of study, the MRSA prevalence was 44.1%, and 389 MRSA strains were included. The prevalence of MRSA was found to be significantly higher in the patients of Indian ethnicity (P < 0.001). The majority (92.5%) of the isolates belonged to ST-239, spa type t037, and possessed the type III or IIIA SCCmec. The arginine catabolic mobile element (ACME) arcA gene was detected in three (1.05%) ST-239 isolates. We report the first identification of ACME arcA gene-positive ST-239. Apart from this predominant clone, six (1.5%) isolates of ST-22, with two related spa types (t032 and t4184) and a singleton (t3213), carrying type IVh SCCmec, were detected for the first time in Asia. A limited number of community-acquired (CA) MRSA strains were also detected. These included ST-188/t189 (2.1%), ST-1/t127 (2.3%), and ST-7/t091 (1%). Panton-Valentin leukocidin (PVL) was detected in all ST-1 and ST-188 strains and in 0.7% of the ST-239 isolates. The majority of the isolates carried agr I, except that ST-1 strains were agr III positive. Virulence genes seg and sei were seen only among ST-22 isolates. In conclusion, current results revealed the predominance of ST-239-SCCmec III/IIIA and the penetration of ST-22 with different virulence gene profiles. The emergence in Malaysia of novel clones of known epidemic and pathogenic potential should be taken seriously.

Surveillance of antibacterial resistance in Staphylococcus aureus isolated in Kuwaiti hospitals

OBJECTIVE

To investigate the prevalence of antibiotic resistance among Staphylococcus aureus isolated in Kuwaiti hospitals.

MATERIALS AND METHODS

S. aureus were isolated and identified following standard microbiological methods. Antibacterial susceptibility test was performed by disk diffusion and the measurement of minimum inhibitory concentration with E-test strips.

RESULTS

A total of 1,846 S. aureus isolates were analyzed from 13 hospitals between 1 March and 30 October 2005. They were isolated from 1,765 (95.6%) inpatients and 81 (4.4%) outpatients. Methicillin resistance was detected in 588 (32.0%) of the isolates. The methicillin-resistant S. aureus (MRSA) consisted of 461 (78%) multiresistant and 127 (22%) nonmultiresistant isolates. The nonmultiresistant MRSA consisted of epidemic MRSA-15 and community-associated MRSA. The community-associated MRSA was detected in all hospitals with MRSA, indicating its establishment in Kuwaiti hospitals. The proportion of isolates resistant to gentamicin, kanamycin, erythromycin, tetracycline, ciprofloxacin, fusidic acid and trimethoprim was higher among MRSA than methicillin-susceptible S. aureus (MSSA) isolates. Twenty-four and 22% of MRSA and MSSA isolates, respectively, expressed reduced susceptibility to vancomycin (minimum inhibitory concentration = 3-4 mg/l).

CONCLUSION

The study revealed the presence of methicillin resistance in 32% of S. aureus isolated in Kuwaiti hospitals and revealed an increase in the number of MRSA and MSSA with reduced susceptibility to vancomycin.

Antibacterial resistance and their genetic location in MRSA isolated in Kuwait hospitals, 1994-2004

Background

Methicillin-resistant Staphylococcus aureus (MRSA) continues to be a major cause of serious infections in hospitals and in the community worldwide. In this study, MRSA isolated from patients in Kuwait hospitals were analyzed for resistance trends and the genetic location of their resistance determinants.

Methods

Between April 1994 and December 2004, 5644 MRSA isolates obtained from different clinical samples were studied for resistance to antibacterial agents according to guidelines from the National Committee for Clinical Laboratory Standards and the British Society for Antimicrobial Chemotherapy. The genetic location of their resistance determinants was determined by curing and transfer experiments.

Results

They were resistant to aminoglycosides, erythromycin, tetracycline, trimethoprim, fusidic acid, ciprofloxacin, chloramphenicol, rifampicin, mupirocin, cadmium acetate, mercuric chloride, propamidine isethionate and ethidium bromide but susceptible to vancomycin, teicoplanin and linezolid. The proportion of the isolates resistant to erythromycin, ciprofloxacin and fusidic acid increased during the study period. In contrast, the proportion of isolates resistant to gentamicin, tetracycline, chloramphenicol and trimethoprim declined. High-level mupirocin resistance increased rapidly from 1996 to 1999 and then declined. They contained plasmids of 1.9, 2.8, 3.0, 4.4, 27 and 38 kilobases. Genetic studies revealed that they carried plasmid-borne resistance to high-level mupirocin resistance (38 kb), chloramphenicol (2.8 – 4.4 kb), erythromycin (2.8–3.0 kb) and cadmium acetate, mercuric chloride, propamidine isethionate and ethidium bromide (27 kb) and chromosomal location for methicillin, the aminoglycosides, tetracycline, fusidic acid, ciprofloxacin and trimethoprim resistance. Thus, the 27 kb plasmids had resistance phenotypes similar to plasmids reported in MRSA isolates in South East Asia.

Conclusion

The prevalence of resistance to erythromycin, ciprofloxacin, high-level mupirocin and fusidic acid increased whereas the proportion of isolates resistant to gentamicin, tetracycline, chloramphenicol and trimethoprim declined during the study period. They contained 27-kb plasmids encoding resistance to cadmium acetate, mercuric chloride, propamidine isethionate and ethidium bromide similar to plasmids isolated in MRSA from South East Asia. Molecular typing of these isolates will clarify their relationship to MRSA from South East Asia.