Endogenous methicillin resistant staphylococcus aureus as a source of post-operative surgical site infections.

OBJECTIVE: To determine frequency of Endogenous Methicillin Resistant Staphylococcus aureus (MRSA) in pre-operative patients and its frequency in Surgical Site Infections (SSIs) post operatively. METHODS: It was a descriptive cross sectional conducted at Department of Microbiology, Fauji Foundation Hospital Rawalpindi (FFH), Pakistan. Samples were collected from 1st November-31st May 2018. Total 75 samples were collected during the period. Consecutive non-probability sampling technique was utilized. Specimens were collected from nose, axilla and groin of preoperative patients. Methicillin Resistant Staphylococcus aureus was identified if only isolated from these sites. Patients were followed till his/her discharge from the hospital and if they developed infection post operatively, pus specimen from infected site was also collected and identified. RESULTS: Out of 75 specimen preoperatively, 11(14.7%) were identified as endogenous MRSA. From these, 33(44%) developed Surgical site infections (SSIs), among them 19(57%) were MRSA (09 endogenous, 10 exogenous), 7(21.2%) were Escherichia coli, 3(9.1%) were Klebsiella pneumoniae, 3(9.1%) were Enterococcus faecalis and 1(3%) was Methicillin Sensitive Staphylococcus aureus. CONCLUSIONS: The results of this study determined that Endogenous Methicillin Resistant Staphylococcus aureus (MRSA) could be isolated from patients going for surgery if microbiological screening was done at the time of admission. This could prevent patients from Surgical Site Infection Post operatively by these endogenous MRSA. This search and wipe out strategy is able to curtail the events of outbreak, reduce hospital stay and decrease budget of the hospital by providing guidance in choice of empirical therapy for infection.

Reviving the role of mecillinam against extended spectrum beta-lactamase producing enterobacterales.

Background and Objectives: This study was designed to determine the in vitro efficacy of mecillinam against extended spectrum beta lactamse producing Enterobacterales. Materials and Methods: After proper permission from Ethical Review Committee of the Institute, all samples yielding growth of ESBL producing Enterobacterales were part of the study and were processed according to routine microbiological procedures. Routine antibiotic sensitivity testing was done on Muller Hinton Agar by Modified Kirby Bauer Method. All Gram negative isolates were subjected to concomitant detection of ESBL production by double disc synergy method. All ESBL producers were then subjected to the mecillinam Minimum Inhibitory Concentration (MIC) determination by E test. The results were interpreted as per CLSI Guidelines. Results: A total of 120 ESBL producing Enterobacterales isolates were included in the study. The mean age of patients with ESBL infection was 45 ± 18.7 years. There were 44% male and 55% female patients. Majority of the ESBL producing Enterobacterales were isolated from urine samples (56%), followed by pus. Among the isolated organisms, Escherichia coli (45%) was the most frequently isolated organism followed by Klebsiella spp. (22%). Overall 83% of the isolates turned out to be sensitive to mecillinam. MIC50 of mecillinam against ESBL producing Gram negative rods (GNR) turned out to be 1 ug/ml and MIC90 turned out to be 2 ug/ml. Conclusion: Mecillinam shows good in vitro efficacy against ESBL producing Enterobacterales in our study. Further studies with more sample size and from diverse areas across the country should be done to evaluate its efficacy.

Aerobic vaginal pathogens and their sensitivity pattern.

BACKGROUND: The vaginal flora is a complicated environment, containing dozens of microbiological species in variable quantities and relative proportions. The frequent cause of vaginal discharge is an infection or colonization with different microorganisms. Some pathologic conditions causing vaginitis are well defined yet, 7-72% of women with vaginitis may remain undiagnosed and such forms of abnormal vaginal flora neither considered as normal, nor can be called bacterial vaginosis have been termed as 'intermediate flora' and its management probably differ from that of bacterial vaginosis. It is of crucial importance in pregnant females at risk of preterm delivery. The present study has been conducted especially to elucidate this type of aerobic vaginal isolates and their culture and sensitivity towards currently used antibiotics. This study was conducted at the Microbiology Department of Fauji Foundation Hospital, Rawalpindi over a period of two years (April 2004-March 2006). METHODS: One thousand, nine hundred and twenty three high vaginal swabs, both from indoor and outdoor patients were collected, cultured and their susceptibility to various antibiotics was determined. RESULTS: Significant growth was obtained in 731 samples. The highest frequency of infection (39.5%) was observed at 31-40 years followed by 41-50 years (35.8%). About 76% were from outdoor and 24% were from indoor patients. Staphylococcus aureus was the most prevalent vaginal pathogen at 11-60 yrs & with highest prevalence at 31-40 years followed by 41-50 years. It was a predominant pathogen in both indoor (35%) as well as outdoor (41.6%) patients, followed by enteric gram-negative bacilli and other gram-positive cocci. There were very few antibiotics among the conventionally available aminoglycosides, third generation cephalosporins, penicillin, quinolones, sulfonamides and tetracyclines possessing good sensitivity (> 80%) against any one the common aerobic vaginal pathogens. The effective chemotherapeutics agents belong to the groups of carbapenems and beta-lactams beta-lactamase inhibitor combinations. CONCLUSIONS: The high prevalence of gynaecological infections demands that the patients with gynaecological symptoms be investigated thoroughly. Culture must invariably be done. Currently the antibiotics showing good sensitivity are very expensive. So there is a need for an effective antimicrobial policy. Effective drug should be reserved for the treatment of serious life threatening situations only.

Extended spectrum beta-lactamases in enteric gram-negative bacilli: related to age and gender.

BACKGROUND: Extended Spectrum beta-Lactamases (ESBLs)-producing strains of Enterobacteriaceae have emerged as a major problem in hospitalized as well as community based patients. Infections due to ESBLs-producers range from uncomplicated urinary tract infection to life threatening sepsis. The objective of this study was to find out the prevalence of ESBLs-producing Gram- negative bacilli among clinical isolates. METHODS: This descriptive study was conducted at the Microbiology department of Fauji Foundation Hospital, Rawalpindi over a period of two years (March 2004-April 2006). Six hundred and nine isolates of Enteric Gram-negative rods from various samples were tested for ESBLs-production by double disc synergy test. In 176 ESBLs-producing isolates, source of samples in term of indoor/outdoor was analyzed. In 165 ESBLs-producing isolates, patients' gender and age was analysed from 3 months to 70 years. RESULTS: The ESBLs-producing isolates were more commonly isolated from indoor patients (88.1%) as compared to outdoor patients (11.9%). Escherichia coli was found to be most prevalent organism in indoor patients while Klebsiella pneumoniae, was the most prevalent organism in outdoor patients. ESBLs were most commonly isolated from female patients (64.3%) suffering from urinary tract infections ((41.5%), as compared to male patients (35.7%) in which the organisms were most commonly isolated from pus samples (54.2 %). ESBLs-producing Enteric Gram-Negative rods were most frequent at later part of life where they were most common (27.9%) at 61-70 years, followed by 41-50 years of age group (20.0%). Another peak (13.3%) was also seen at younger age group (11-20 years). The least prevalence (5.5%) was seen in two age groups (0-10 and 31-40 yrs). In case of female patients, ESBLs-producing EGNR were most frequently (29.2%) isolated from middle age group (41-50 years) followed by later age groups (51-60 and 61-70 years, (15.1% and 25.5%). CONCLUSIONS: Considering the high prevalence of ESBLs in Enteric Gram-negative rods, it is suggested that all such isolates should be tested for the production of ESBLs in the routine microbiology laboratory.

Outbreak Of Extensively Drug Resistant Stenotrophomonas Maltophilia In Burn Unit.

Stenotrophomonas maltophiliais an emerging cause of nosocomial infections. We report an outbreak of XDR-Stenotrophomonas maltophilia infection from burn unit of a tertiary care hospital in July 2016. The strain isolated was resistant to all antimicrobials tested but colistin. Outbreak investigation was carried out which subsided after timely intervention. Patients were treated adequately by Colistin.