Debadatta Panigrahi

Prevalence and Antimicrobial Susceptibility Pattern of Extended-Spectrum Beta-Lactamase-Producing Enterobacteriaceae in the United Arab Emirates

Objective: To investigate the prevalence and antibiotic susceptibility pattern of extended-spectrum β-lactamases (ESBL)-producing Enterobacteriaecae among patients in the United Arab Emirates. Materials and Methods: A total of 130 Enterobacteriaceaecomprising of Escherichia coli (n = 83), Klebsiella pneumoniae (n = 45) and Klebsiella oxytoca (n = 2) was studied. Of these 130 isolates, 64 were from urine. ESBL screening was by disc diffusion and confirmatory tests for ESBL phenotype were conducted using BD Phoenix™ ESBL System and cephalosporin/clavulanate combination discs. Susceptibility to a panel of antibiotics was evaluated. Results: Of the 130 isolates, 53 (41%) were identified as having ESBL phenotype; of these, 32 (60%) were E. coli, 20 (36%) K. pneumoniae and 2 (4%) K. oxytoca. ESBL phenotype was seen in 100% of endotracheal tubes isolates, 20 (31%) from urine, 7 (58%) from blood and 4 (80%) from catheter tips. Amikacin susceptibility was 100%. Over 90% of ESBL isolates showed resistance to aztreonam and cephalosporins. All Klebsiella isolates were carbapenem sensitive. One ESBL isolate showed intermediate resistance to imipenem and meropenem (both MIC 8 µg/ml), cefotetan (MIC 32 µg/ml) and piperacillin/tazobactam (MIC 32 µg/ml). MIC for the carbapenems was lower in non-ESBL isolates (0.034 µg/ml) than ESBL isolates (0.071 µg/ml). Resistance to gentamicin, ciprofloxacin and piperacillin/tazobactam was higher in ESBL than non-ESBL isolates (p < 0.05). Conclusion: A high prevalence of ESBL-producing bacteria exists among in-patients in the United Arab Emirates. Amikacin and carbapenems remain the most effective drugs, but the presence of carbapenem-resistant ESBL-producing E. coli and occurrence of multidrug resistance are of concern. Continued surveillance and judicious antibiotic usage are recommended.

Prevalence of Intestinal Parasitic Infections in Sharjah, United Arab Emirates

A survey of prevalence of intestinal parasites among the expatriates and native Emirati people attending Ministry of Health hospitals in Sharjah, United Arab Emirate was performed during the year 2008 and 2009. Stool examination from 10,514 patients (64% expatriates and 36% native Emiratis) was performed. Eight hundred fourteen specimens of the 10,514 examined were found to be positive for intestinal parasites. The infection rates were 15.7% and 3.2% among the native and expatriate population respectively (odds ratio = 5.5). The rate of infection in males (58%) was higher than in females (42%). Overall, protozoa infections (92.2%) were higher than the helminth infections (7.8%). Entamoeba histolytica (71.8%) and Giardia lamblia (17.5%) were the commonest intestinal parasites identified. Among the helminths, Ancylostoma dudenale and Ascaris lumbricoides were the common ones. In comparison to helminthic infestations, protozoa infections were more common among the native Emirati population than the expatriate population. The high prevalence rate of intestinal parasitic infections among the local Emirati people clearly indicates that there is continuous ongoing transmission of various parasitic infections in the community.

Molecular Typing of Methicillin-Resistant Staphylococcus aureusIsolated in a Bahrain Hospital

Objective: To investigate antibacterial resistance patterns and genetic relatedness of methicillin-resistant Staphylococcus aureus (MRSA) obtained at the Salmaniya Medical Complex in Bahrain. Methods: A total of 53 consecutive MRSA isolates obtained from 53 patients were studied using antibacterial resistance patterns, coagulase gene polymorphism, staphylococcal cassette chromosome mec (SCCmec) typing and pulsed-field gel electrophoresis (PFGE). Results: There was a high prevalence of resistance to fusidic acid (92.5%), ciprofloxacin (92.5%), erythromycin (90.6%), tetracycline (88.7%), trimethoprim (88.7%), streptomycin (88.7%), kanamycin (83.0%) and gentamicin (73.6%). Coagulase gene typing divided the isolates into five coagulase types comprising coagulase type 36 (86.7%), type 20 (3.8%), type 16 (3.8%), type 38 (1.9%) and type 384 (3.8%). They belonged to SCCmec type III (86.7%) and SCCmec type IV (13.3%). PFGE identified five pulsotypes (types A–E) with PFGE type A and its subtypes comprising 83% of the isolates. PFGE type A isolates were multiresistant and had the SCCmec type III and coagulase type 36 genotype. The SCCmec type IV isolates were nonmultiresistant with different genetic backgrounds. Conclusions: The study identified two types of MRSA in the hospital during the study period. One type consisted of a persistent multiresistant PFGE clone with the SCCmec type III and coagulase type 36 genotypes. The second type consisted of nonmultiresistant isolates that belonged to different genetic backgrounds and were isolated less frequently.

Distribution and Resistance Trends of Community Associated Urinary Tract Pathogens in Sharjah, UAE

Objective To describe the spectrum of etiologic agents causing community associated UTI and their antimicrobial resistance trends in a large teaching hospital in Sharjah, United Arab Emirates. Methods A retrospective review of the microbiology laboratory records of four hundred ninety two cases of community associated UTI between April 2006 and March 2007 was carried out. Etiologic agents and their antimicrobial susceptibility pattern were analyzed. Results A wide spectrum of uropathogens was isolated of which the leading etiologic agents of community associated UTI were Escherichia coli (207 strains) and Klebsiella species (90 strains). Sixty-six per cent of Gram-negative bacilli were resistant to amoxicillin, 58.5% were resistant to trimethoprim-sulfamethoxazole and more than 50% were resistant to cephalexin. However, resistance rate to antimicrobials like ciprofloxacin and ceftriaxone remain relatively low 9.7% and 7.6% respectively. Conclusions Escherichia coli remains the leading cause of community associated UTI. In-vitro antimicrobial resistance pattern of the isolates revealed that trimethoprim-sulfamethoxazole, cephalexin and amoxycillin the commonly used first-line antimicrobials were becoming less and less effective in their treatment. This information can help in changing preferences of suitable antimicrobial agent in treatment of community associated UTI.

Extended-Spectrum β-Lactamase-Producing Enterobacteriaceae: In vitro Susceptibility to Fosfomycin, Nitrofurantoin and Tigecycline

Objective: To assess the susceptibility trends of community-acquired extended-spectrum β-Iactamase (ESBL)-producing urinary isolates with particular reference to fosfomycin, nitrofurantoin and tigecycline. Materials and Methods: Seven hospitals across the United Arab Emirates participated in this study from June 2008 to March 2010. The antibiotic sensitivity of ESBL-producing uropathogens to a panel of antibiotics including tigecycline, fosfomycin and nitrofurantoin was assessed. The Hyplex ESBL identification system (h-ES-ID) was used for genotypic identification. Results: Two hundred and ninety-two ESBL-producing Enterobacteriaceae isolates were identified during the study period. Of these, 182 (62%) were urinary isolates and comprised of Escherichia coli: 149 (81.9%), Klebsiella pneumoniae: 30 (16.5%) and Proteus mirabilis: 3 (1.6%). Of the 182 urinary isolates, 179 (98.3%) were from patients with community onset urinary tract infections. The h-ES-ID system identified 172 (94.5%) of the urinary isolates as CTX-M positive. All isolates were susceptible to imipenem and meropenem. Over half of the isolates showed resistance to gentamicin (98; 53.8%), trimethoprim-sulfamethoxazole (139; 76.4%) and ciprofloxacin (143; 78.6%). Sensitivity to nitrofurantoin and fosfomycin was 90 and 100%, respectively. Two CTX-M-positive K. pneumoniae isolates with tigecycline resistance (MIC >4 µg/ml) were identified. Conclusion: There is dissemination of CTX-M ESBL-producing urinary pathogens into the community. Fosfomycin and nitrofurantoin were active against ESBL-positive uropathogens, and emergence of tigecycline resistance needs close monitoring.

Incidence of community‐acquired methicillin‐resistant Staphylococcus aureus carrying Pantone‐Valentine leucocidin gene at a referral hospital in United Arab Emirates

Community‐acquired methicillin‐resistant Staphylococcus aureus (CA‐MRSA) is an emerging pathogen in hospitalized patients worldwide. The present study was undertaken to identify CA‐MRSA in hospitalized patients in a 350‐bed tertiary care hospital in Sharjah, UAE over a 2‐year period from January 2011 to December 2012. CA‐MRSA was defined based on identification within first 48 h of admission in the hospital. Staphylococcal cassette chromosome (SCC) mec typing of the CA‐MRSA isolates was carried out by multiplex polymerase chain reaction (PCR). Detection of PVL and mecA genes was done by PCR using the GenoType® MRSA test system (Hain Lifescience). Patients clinical data and antimicrobial susceptibility pattern of the CA‐MRSA isolates were also evaluated. Fifty seven of the 187 MRSA isolates were identified as CA‐MRSA. All the CA‐MRSA strains in our study belonged to SCCmecIV type and were positive for both PVL and mecA genes. The patients with CA‐MRSA infections were young (median age, 32 years) and the majority of infections involved the skin and soft tissue (36%). Antimicrobial susceptibility pattern of the CA‐MRSA isolates showed a better susceptibility profile to the non‐beta‐lactam antimicrobials with the exception of ciprofloxacin having 28% resistance. This study evidently strengthens the recent observation of an increase in CA‐MRSA emergence among hospitalized patients in the UAE.

Misidentification of Brucella melitensis as Bergeyella zoohelcum by MicroScan WalkAway®: a case report.

Objective: To describe the misidentification of Brucella melitensis as Bergeyella zoohelcum by MicroScan WalkAway®, a commonly used bacterial identification system. Clinical Presentation and Intervention: A 35-year-old man was admitted to the Intensive Care Unit with sepsis syndrome. Three sets of aerobic blood culture samples were positive after 48 h of incubation. The isolated organism was identified as B. zoohelcum using the MicroScan WalkAway (Siemens Healthcare Diagnostics Inc., West Sacramento, Calif., USA). However, due to the rareness of the pathogen, the isolate was reidentified as B. melitensis with Vitek® 2 system and later 16S ribosomal sequence analysis confirmed the isolate as B. melitensis having 100% match. Conclusion: This case showed that Brucella can be misidentified using MicroScan WalkAway. Countries where brucellosis is endemic need to be careful while using such automated identification systems in order not to miss the diagnosis of Brucella.