Multi-Drug Resistance Bacteria: A Case Study in Western Peninsular Malaysia Freshwaters

The emergence of antibiotic resistant bacteria in aquatic environment has led to an increase in waterborne health risks to an alarming extent. This study attempts to investigate the population of certain antibiotic resistant strains in Peninsular Malaysia. From the samples of 14 rivers from 7 different states in Peninsular Malaysia, a total of 203 isolates were successfully isolated. These are from rivers in Negeri Sembilan, Melaka, Selangor, Kuala Lumpur, Kedah, Kelantan and Terengganu with 35, 15, 37, 39, 24, 26 and 27 isolates, respectively. The isolates were tested for their susceptibility towards 6 broad spectrum of antibiotics which are gentamicin, ampicillin, rifampicin, chloramphenicol, tetracycline, and ciprofloxacin. A total of 117 isolates were identified to have more than 20% MAR index value with 47 of the isolates possess minimum MAR index value of 50%. Based on MAR index value, 59% of isolates are high risk threats indicating a serious emergence of antibiotic resistant bacteria in the rivers in Peninsular Malaysia. Isolates with MAR index value of more than 50% were selected for 16S rRNA gene sequencing for further identification.Based on 16s rRNA gene sequencing, the isolates are a mixture of pathogenic and commensals bacteria. This also implies that the environment especially rivers can be a reservoir for genetic jugglery

BACTERIAL INFECTION AND ANTIBIOTIC RESISTANCE IN PATIENTS WITH HUMAN IMMUNODEFICIENCY VIRUS PRESENTING LOWER RESPIRATORY TRACT INFECTION IN NIGERIA

Lower Respiratory Tract Infection (LRTI) is associated with mortality and prolonged antibiotics use among HIV/AIDS patients. Sputum samples were collected from 134 HIV/AIDS patients with LRTI and productive cough, visiting University of Abuja Teaching Hospital, Nigeria, to determine the bacterial aetiologies and antibiotic resistance profile. Adequate for culture sputum samples were observed in only 119 subjects (75 females and 44 males) and cultured using standard procedure. Isolates were identified by biochemical method and 16SrRNA gene amplification, purification, sequencing and database nucleotide blast. Antibiotic susceptibility tests were performed and interpreted according to Clinical and Laboratory Standard Institute (CLSI) procedures. Bacteria associated LRTI was found in 20.2% of the patients and Klebsiella pneumonia (29.7%); Enterobacter cloacae (16.7%); Enterobacter hormaechei subsp. xiangfangensis (12.5%); Pseudomonas parafulva; Pseudomonas aeruginosa; Pseudomonas alcaliphila; Klebsiella aerogenes (8.3%); Comamonas testosteroni; Escherichia coli; Acinetobacter junii; Acinetobacter soli and Acinetobacter baumannii were implicated. Isolates show high resistance to amoxicillin-clavulanic acid at 94.1%, trimethoprim-sulfamethoxazole at 75.0% and cefotaxime at 70.0%. The Multiple Antibiotic Resistance (MAR) index of most isolates (62.5%) is within 0.3-0.8 in a range of 0.0 to 0.8. Isolates of the same species were found to have different MAR index in different patients. However, E. cloacae, E. hormaechei subsp. xiangfangensis, A. baumanni and 71.4% of K. pneumonia were Multi-drug Resistant (MDR). Interestingly, Gentamycin, Ciprofloxacin and Imipenem were effective against MDR isolates and showed significant negative correlation with MAR index. We propose that antibiotics with efficacy against MDR isolates could be used to down regulate the selective pressure of other antibiotics, and these MDR pathogens, including those rarely associated with human infection poses potential threat, similar to Methicillin Resistant Staphylococcus aureus (MRSA). Particularly, among the immunocompromised. Furthermore, HIV/AIDS patients present good metrics for profiling the burden and spread of antibiotic resistant bacteria in poor countries.

Co-Existence of Certain ESBLs, MBLs and Plasmid Mediated Quinolone Resistance Genes among MDR E. coli Isolated from Different Clinical Specimens in Egypt

The emergence of multi-drug resistant (MDR) strains and even pan drug resistant (PDR) strains is alarming. In this study, we studied the resistance pattern of E. coli pathogens recovered from patients with different infections in different hospitals in Minia, Egypt and the co-existence of different resistance determinants. E. coli was the most prevalent among patients suffering from urinary tract infections (62%), while they were the least isolated from eye infections (10%). High prevalence of MDR isolates was found (73%) associated with high ESBLs and MBLs production (89.4% and 64.8%, respectively). blaTEM (80%) and blaNDM (43%) were the most frequent ESBL and MBL, respectively. None of the isolates harbored blaKPC and blaOXA-48 carbapenemase like genes. Also, the fluoroquinolone modifying enzyme gene aac-(6′)-Ib-cr was detected in 25.2% of the isolates. More than one gene was found in 81% of the isolates. Azithromycin was one of the most effective antibiotics against MDR E. coli pathogens. The high MAR index of the isolates and the high prevalence of resistance genes, indicates an important public health concern and high-risk communities where antibiotics are abused.

Characterization and Analysis of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPRs) in Pandemic and Non-Pandemic Vibrio parahaemolyticus Isolates from Seafood Sources

Vibrio parahaemolyticus is one of the significant seafood-borne pathogens causing gastroenteritis in humans. Clustered regularly interspaced short palindromic repeats (CRISPR) are commonly detected in the genomes of V. parahaemolyticus and the polymorphism of CRISPR patterns has been applied as a genetic marker for tracking its evolution. In this work, a total of 15 pandemic and 36 non-pandemic V. parahaemolyticus isolates obtained from seafood between 2000 and 2012 were characterized based on hemolytic activity, antimicrobial susceptibility, and CRISPR elements. The results showed that 15/17 of the V. parahaemolyticus seafood isolates carrying the thermostable direct hemolysin gene (tdh+) were Kanagawa phenomenon (KP) positive. The Multiple Antibiotic Resistance (MAR) index ranged between 0.1 and 0.4, and 45% of the isolates have an MAR index ≥ 0.2. A total of 19 isolates were positive for CRISPR detection, including all tdh+ trh− isolates, two of tdh− trh+, and each of tdh+ trh+ and tdh− trh−. Four spacer types (Sp1 to Sp4) were identified, and CRISPR-positive isolates had at least one type of spacer homolog to the region of Vibrio alginolyticus megaplasmid. It is of interest that a specific CRISPR profile and spacer sequence type was observed with correlations to the hemolysin genotype (tdh/trh). Thus, these provide essential data on the exposure of foreign genetic elements and indicate shared ancestry within different genotypes of V. parahaemolyticus isolates.

Features of oral immunity indicators in patients with phlegmons of the maxillofacial region against the background of insulin-independent diabetes mellitus

Objective: studying the interrelations of the local oral immunity indicators which allow to predict the severity of phlegmons course in patients with maxillofacial region phlegmons against the background of insulin-independent diabetes mellitus. Materials and methods. 44 patients were included in this prospective study. The main group: 19 patients with the maxillofacial region phlegmons and the type 2 diabetes mellitus as a concomitant pathology (PH+DM). The comparison group: 20 patients with the maxillofacial region phlegmons with no diabetes mellitus among the concomitant pathologies (PH). The control group: 5 patients were undergoing routine surgical treatment in the maxillofacial surgery department. The groups were comparable in age, gender, and phlegmon treatment (p > 0.05). Levels of the proinflammatory and anti-inflammatory cytokines, the humoral immunity factors and the microbial adsorption reaction (MAR) index to the oral epithelial cells were determined in the saliva of patients on the 1st and 5th days. The obtained data were statistically processed. Results. On the 1st day of hospital treatment the PH+DM group revealed an increase in interleukin-6, a decrease in interleukin-10 and lactoferrin as compared to the PH and control groups (p < 0.05). On the 5th day of the treatment the interleukin-6 and tumor necrosis factor-α levels did not differ between PH+DM and the control groups (p < 0.05). The interleukin-4 and interleukin-10 levels were lower in the PH+DM and PH groups than in the control group on the 5th day (p < 0.05). The lactoferrin level in the PH+DM group was lower than in the PH and control groups (p < 0.05). The significant negative correlation was found between the MAR index values and SOFA (Sequential organ failure assessment score) points in patients with sepsis, R = -0.9 (p < 0.05). Conclusion. The delayed regression of the saliva inflammation indicators was specific for the PH+DM group patients in comparison with the PH group patients. The MAR index below 10% may be a predictor of unfavorable course of the phlegmon development.

Lentic and effluent water of Delhi-NCR: a reservoir of multidrug-resistant bacteria harbouring blaCTX-M, blaTEM and blaSHV type ESBL genes

Antimicrobial resistance is not restricted to clinics but also spreading fast in the aquatic environment. This study focused on the prevalence and diversity of extended-spectrum β-lactamase (ESBL) genes among bacteria from lentic and effluent water in Delhi-NCR, India. Phenotypic screening of 436 morphologically distinct bacterial isolates collected from diverse sites revealed that 106 (∼24%) isolates were ESBL positive. Antibiotic profiling showed that 42, 60, 78 and 59% ESBL producing isolates collected from Ghazipur slaughterhouse, Lodhi garden pond, Hauz Khas lake and Jasola wastewater treatment plant, respectively, were multidrug-resistant (MDR). The multiple antibiotic resistance (MAR) index varied from 0.20 to 0.32 among selected locations. The prevalence of ESBL gene variants blaSHV, blaTEM and blaCTX-M were found to be 17.64, 35.29 and 64%, respectively. Furthermore, the analysis of obtained gene sequences showed three variants of blaCTX-M (15, 152 and 205) and two variants of blaTEM (TEM-1 and TEM-116) among ESBLs producers. The co-existence of 2–3 gene variants was recorded among 48% ESBL positive isolates. New reports from this study include the blaCTX-M gene in Acinetobacter lwoffii, Enterobacter ludwigii, Exiguobacterium mexicanum and Aeromonas caviae. Furthermore, the identification of blaTEM and blaSHV in an environmental isolate of A. caviae is a new report from India.

Prevalence of Pseudomonas in dental unit water of private dental clinics and its antimicrobial susceptibility using MAR index

The bacteriology of water in a dental unit is important as potentially pathogenic microorganisms like Pseudomonas may be present in dental water unit, which could be fatal for immuno-compromised patients and be of significant morbidity in immuno-competent patients. It is difficult to treat infections caused by Pseudomonas due to their resistance to many commonly used disinfectants and antibiotics. The aim of the present study was to evaluate the Pseudomonas contamination in dental unit water lines of a dental hospital outpatient department and to analyse the antimicrobial susceptibility of Pseudomonas.

Multidrug-Resistant Coagulase-Negative Staphylococci Isolated from Bloodstream in the uMgungundlovu District of KwaZulu-Natal Province in South Africa: Emerging Pathogens

Coagulase-negative staphylococci (CoNS) are increasingly associated with nosocomial infections, especially among the immunocompromised and those with invasive medical devices, posing a significant concern. We report on clinical multidrug-resistant CoNS from the uMgungundlovu District, KwaZulu-Natal Province, South Africa, as emerging pathogens. One hundred and thirty presumptive CoNS were obtained from blood cultures. Culture, biochemical tests, and the Staphaurex™ Latex Agglutination Test were used for the initial identification of CoNS isolates; confirmation and speciation were undertaken by the VITEK 2 system. Susceptibilities of isolates against a panel of 20 antibiotics were determined using the Kirby-Bauer disk diffusion method, and the multiple antibiotic resistance (MAR) indices of the isolates were determined. The polymerase chain reaction (PCR) was used to amplify the mecA gene to confirm methicillin resistance. Overall, 89/130 presumptive CoNS isolates were confirmed as CoNS by the VITEK 2 system. Of these, 68 (76.4%) isolates were putatively methicillin-resistant by the phenotypic cefoxitin screen test and 63 (92.6%) were mecA positive. Staphylococcus epidermidis (19.1%), S. hominis ssp. hominis (15.7%), and S. haemolyticus (16.9%) were the most common CoNS species. Isolates showed high percentage resistance against penicillin (100.0%), erythromycin (74.2%), and azithromycin (74.2%) while displaying high susceptibilities to linezolid (95.5%), gentamicin (95.5%), and tigecycline (94.4%). Multidrug resistance (MDR) was observed in 76.4% of isolates. MAR index calculation revealed 71.9% of isolates with MAR index >0.2 and 20.2% >0.5. Isolates with the highest MAR indices (0.7 and 0.8) were recovered from the neonatal intensive care unit. Fifty-one MDR antibiograms were observed. The high prevalence of methicillin resistance and multidrug resistance in several species of CoNS necessitates surveillance of this emerging pathogen, currently considered a contaminant of microbial cultures.

Molecular Detection of Antibiotic-Resistant Genes in Pseudomonas aeruginosa from Nonclinical Environment: Public Health Implications in Mthatha, Eastern Cape Province, South Africa

Evaluation of resistant profiles and detection of antimicrobial-resistant genes of bacterial pathogens in the nonclinical milieu is imperative to assess the probable risk of dissemination of resistant genes in the environment. This paper sought to identify antibiotic-resistant genes in Pseudomonas aeruginosa from nonclinical sources in Mthatha, Eastern Cape, and evaluate its public health implications. Samples collected from abattoir wastewater and aquatic environment were processed by membrane filtration and cultured on CHROMagarTM Pseudomonas medium. Species identification was performed by autoSCAN-4 (Dade Behring Inc., IL). Molecular characterization of the isolates was confirmed using real-time polymerase chain reaction (rPCR) and selected isolates were further screened for the possibility of harboring antimicrobial resistance genes. Fifty-one Pseudomonas species were recovered from abattoir wastewater and surface water samples, out of which thirty-six strains were Pseudomonas aeruginosa (70.6%). The P. aeruginosa isolates demonstrated resistance to aztreonam (86.1%), ceftazidime (63.9%), piperacillin (58.3%), cefepime (55.6%), imipenem (50%), piperacillin/tazobactam (47.2%), meropenem (41.7%), and levofloxacin (30.6%). Twenty out of thirty-six P. aeruginosa displayed multidrug resistance profiles and were classified as multidrug-resistant (MDR) (55.6%). Most of the bacterial isolates exhibited a high Multiple Antibiotic Resistance (MAR) Index ranging from 0.08 to 0.69 with a mean MAR index of 0.38. In the rPCR analysis of fifteen P. aeruginosa isolates, 14 isolates (93.3%) were detected harboring blaSHV, six isolates (40%) harbored blaTEM, and three isolates (20%) harbored blaCTX-M, being the least occurring ESBL. Results of the current study revealed that P. aeruginosa isolates recovered from nonclinical milieu are resistant to frontline clinically relevant antipseudomonal drugs. This is concerning as it poses a risk to the environment and constitutes a public health threat. Given the public health relevance, the paper recommends monitoring of multidrug-resistant pathogens in effluent environments.