Multidrug resistance among gram-positive bacteria, especially MRSA, has been a major healthcare concern worldwide. The prevalence of infections by multidrug-resistant gram-positive bacteria is growing. Increased use and misuse of antibiotics are among the foremost contributors to the development of antibiotic resistance, especially in India.
Penicillin was the original drug of choice. So, the emergence of resistance was due to the acquisition of plasmid-borne genetic elements encoding beta-lactamases. Subsequently, semisynthetic penicillin was developed for treatment in 1959. Unfortunately, resistance to these agents also emerged during 1980. Methicillin resistance is due to the presence of an altered penicillin-binding protein called penicillin-binding protein 2a that results from the acquisition of a chromosomal gene called mecA which is located within the large mobile staphylococcal chromosomal element known as the SCCmec.
Many SCCmec types and subtypes have been identified. Type 1,11 and 111 are found in hospital-acquired MRSA (HAMRSA) strains, while type 1V, V, and VII are predominantly among community-acquired MRSA (CAMRSA). Staphylococcus. aureus strains that contain SCCmec are termed MRSA [2].
Recently, three types of MRSA could be recognized: Healthcare-associated MRSA, community-acquired MRSA, and Livestock associated MRSA, a new type that arose from animals. CAMRSA strains can spread in the general population with or without exposure to the healthcare environment. It causes infections like soft tissue infections (including necrotizing fasciitis), severe necrotizing pneumonia, sepsis, and bone and joint infection. It is increasingly being observed that CAMRSA is gradually resembling HAMRSA in being more invasive and transmissible than before [3]. CAMRSA outbreaks have occurred among populations such as prisoners, daycare centers, military recruits, and participants in contact sports. HAMRSA infections occur mostly among the elderly, individuals at risk factors like recent hospitalization, living in a long-term care facility, indwelling catheter in place, or recent surgery, and are generally multidrug resistant. The pattern of antibiotic susceptibility of MSSA and MRSA isolates differed significantly. The MSSA isolates were susceptible to most of the antibiotics while MRSA posed a serious therapeutic challenge and can lead to increased mortality and morbidity of the patients. It is resistant to beta-lactam antibiotics, cephalosporins, beta-lactamase inhibitors, and carbapenems. It can further exhibit resistance to other classes of antibiotics. As a result, it can cause an increased overall length of stay in the hospital, more complications, requirement of therapy by multiple antimicrobial agents. These results in an overall increase in the treatment cost, which can be disastrous in a country like India where most of the healthcare expenditure is borne out-of-pocket [4, 5].
The prevalence of MRSA strains has increased worldwide. In India, high rates of MRSA have been reported in clinical isolates from various studies, with rates as high as 54.8% (ranging between 32% and 80% among the S. aureus pool. Studies showed that MRSA among invasive S. aureus isolates was estimated to be 29% in 2009, which increased to around 47% in 2014 [6]. In the present study, the MRSA prevalence rate was 56.79%. A similar prevalence of 54.85% and 59.3% were observed by Anupurba et al. and Tiwari et al., respectively [7, 8]. The MRSA prevalence rates vary in various countries, with some reporting rates higher than ours [9-13]. Whereas the studies done by various author has also found a lower prevalence rate of 41%, 32.22%, 32.12%, and 30% [14-16]. The factors responsible for the rate of variations seen with different studies could be the different geographical areas, variation in sample sizes and length of study, specimens, methods, and status of infection control.
While comparing the gender distribution of MRSA infections, males (67.9%) were more affected than female patients (32.1%). Similar trends were observed by Rao et al. in 2012 [17]. Vancomycin remains the most important drug for the treatment of MRSA [18]. Daptomycin is another useful drug for invasive MRSA infections [19]. Telavancin, ceftaroline, and linezolid may be used for second-line therapy of MRSA [20]. Ceftobiprole is a new broad-spectrum, a "5th generation" cephalosporin activating against gram-positive bacteria, including MRSA [21].
There have been reports from different parts of India isolating MRSA strains with additional resistance to linezolid (Linezolid-resistant MRSA-LRMRSA) [22] and multiple antibiotics such as vancomycin, linezolid, and tigecycline (multidrug-resistant S. aureus- MDRSA) [23]. The emergence of multiple drug resistance among S. aureus isolates may be significant, though the exact prevalence and clinical implications remain to be known. The spread of MRSA infection is promoted by contacts comprising close skin-to-skin contact, skin lesion like cuts or abrasions, contaminated items and surfaces, crowded living conditions, like hospitals and prisons, and poor hand hygiene. Therefore, MRSA can be prevented by the following methods:
- Wash hands thoroughly;
- Cover cuts with antibacterial cream and a clean bandage. This will help the wound heal and also prevent it from spreading bacteria to other people;
- Do not share personal items like towels or razors;
- Washing clothes and linens with regular detergents at the hottest temperature that is safe for the fabric;
- Shower after athletic games or practice.
Conclusion
Antimicrobial resistance is an important communicable disease and a global health and development threat. It is widely considered to be the next global pandemic. Increased use and misuse of antibiotics are among the foremost contributors to the development of antibiotic resistance, especially in India. As reported in 2014, India was the largest consumer of antibiotics for human health in the world at 12.9 × 109 units [24]. Treatment of multi-drug resistant MRSA is still problematic because of the limited choice of antibiotics. The option of the drug for empirical therapy for staphylococcal infections depends on susceptibility data for the local geographic area. Knowledge of MRSA prevalence and their antimicrobial profile in a healthcare setup is crucial to implement control measures like cleanliness, hygiene, and aseptic precaution for these infections and minimize the usage of second-line antimicrobials. The findings of the study have helped us to recommend the empirical therapy schedule to clinicians and implement stringent hospital infection control programs.
Conflict of Interest
The authors have no conflicts of interest to declare.
Acknowledgement
None.