Prevalence of antimicrobial resistance in Acinetobacter calcoaceticus-baumannii complex in a Saudi Arabian hospital

Epidemiology and Multidrug Resistance of Pseudomonas aeruginosa and Acinetobacter baumanni Isolated from Clinical Samples in Ethiopia

Background

A. baumannii and P. aeruginosa are important nosocomial pathogens in health-care settings. Both are intrinsically resistant to many drugs and are able to become resistant to the virtually most antimicrobial agents. An increasing prevalence of infections caused by multidrug-resistant isolates has been reported in many countries.

Methods

An institutional-based cross-sectional five-year retrospective study was conducted to assess the antimicrobial resistance trend of P. aeruginosa and A. baumani. 893 A. baumani and 729 P. aeruginosa isolates were included in the study. Conventional method was used for identification and antimicrobial susceptibility was determined by Kirby-Bauer disc-diffusion method. The isolates were from suspected bloodstream infections, wound infections, urinary tract, or surgical site nosocomial infections. Socio-demographic and other variables of interest were collected using a structured check list from a patient record data. Data were analyzed using SPSS version 26 software. P value <0.05 was considered statistically significant.

Results

A total of 1622 A. baumanii and P. aeruginosa were isolated from various clinical specimens recorded from the year 2017-2021. Out of which A. baumanni was 893 (60.6%) and P. aeruginosa was 729 (39.4%). Blood was the major source of the isolates (18.3%), followed by urine (16%), and tracheal aspirate (10.6%). Antimicrobial resistance among A. baumanni over the five years were; ampicillin (86% to 92%), ceftriaxone (66.7% to 82.2%), and ciprofloxacin (58.5% to 66.7%). In P. aeruginosa a significant increase in resistance was seen from 2017 to 2021 to Amoxicillin-clavulanate (74.1% to 84.2%), chloramphenicol (62% to 81.9%), and gentamicin (40% to 44.8%).

Conclusion

A five-year antimicrobial resistance trend analysis of A. baumanni and P. aeruginosa showed increasing multi drug resistance and resistance to highly potent antimicrobial agents in Ethiopia. It should be addressed with infection control measures, surveillance, and alternative new therapeutic strategies to circumvent the spread of multi-drug resistance.

Transmission of Antimicrobial Resistant Bacteria at the Hajj: A Scoping Review

BACKGROUND

The Hajj is an annual religious mass gathering event held in Makkah, Saudi Arabia. With millions of participants from across the globe attending the Hajj, the risk of importation, transmission, and global spread of infectious diseases is high. The emergence of antimicrobial resistant (AMR) bacteria is of worldwide concern and the Hajj poses a serious risk to its dissemination. This review aims to synthesize published literature on AMR bacteria acquisition and transmission associated with the Hajj.

METHODS

We searched electronic databases to identify literature published between January 1990 and December 2021. The search strategy included medical subject headings and keyword terms related to AMR bacteria and the Hajj.

RESULTS

After screening 2214 search results, 51 studies were included in the analysis. The review found 6455 AMR bacteria transmissions related to the Hajj. Thirty predominantly enteric or respiratory disease-causing AMR bacterial species were reported with isolates identified in cases on five continents. Most were male, aged above 50 years and were diagnosed in Makkah. Most cases were identified through hospital-based research; few cases were detected in community or primary health care settings.

CONCLUSIONS

This review provides a contemporary account of knowledge related to AMR transmission at the Hajj. It emphasizes the need for the enhancement of surveillance for AMR bacteria globally.

Prevalence of Acinetobacter baumannii in Saudi Arabia: risk factors, antimicrobial resistance patterns and mechanisms of carbapenem resistance

Acinetobacter baumannii is an important opportunistic pathogen due to its capabilities for developing mechanisms of resistance to a wide range of antimicrobial agents including carbapenems. This review described the risk factors, antimicrobial susceptibility and mechanisms of carbapenem resistance of A. baumannii from different geographical regions of Saudi Arabia. Several factors including complexity of intensive care unit (ICU) environments, increased numbers of patients with serious diseases, wide spread gastrointestinal colonization and extensive use of antimicrobial drugs led to a wide prevalence of A. baumannii infections in hospitals in Saudi Arabia. A. baumannii has been noted to be less susceptible to antimicrobials agents, including carbapenems, over time, resulting in the evolution of multidrug-resistant (MDR) strains. Dissemination of MDR A. baumannii is attributed to the extreme use of wide-spectrum antimicrobial drugs in hospitals, cross infection between inpatients, invasive ICU procedures, and hospitalized patients with diabetic and cancer those are under frequent invasive diagnostic and therapeutic interventions. Although an increasing prevalence of colistin and tigecycline resistance has been reported in many hospitals, combinations of these agents with carbapenems or other antibiotics remain the best therapeutic choice and reasonably safe to treat patients with MDR A. baumannii infections. The wide distribution of carbapenem resistant A. baumannii (CRAB) due to several mechanisms with diverse genetic determinants has been documented. Although OXA-23 β-lactamase and OXA-51 β-lactamase are the most common genes responsible for CRAB, other novel genes such as blaVIM, PER-1-like and GES-5 have been discovered in carbapenem resistant strains. The high rates of MDR A. baumannii in Saudi hospitals indicate that extensive investigation into the molecular basis of MDR and developing new therapies of CRAB is needed. Moreover, the development of a local antibiogram database coupled with a nationwide antimicrobial stewardship and infection prevention program might help to improve our knowledge of the resistance patterns of A. baumannii, and in developing a treatment protocol for decreasing the infection burden in Saudi Arabia.

Misinterpretation of Gram Stain from the Stationary Growth Phase of Positive Blood Cultures for Brucella and Acinetobacter Species

Introduction:

Acinetobacter baumannii and Brucella species are Gram-negative organisms that are vulnerable to misinterpretation as Gram-positive or Gram-variable in blood cultures.

Objective:

We assess the random errors in gram stain interpretation to reduce the likelihood of such errors and therefore patient harm.

Methodology:

Aerobic and anaerobic blood cultures from two patients in an acute care facility in Saudi Arabia were subjected to preliminary Gram-staining. In case 1, VITEK-2 Anaerobe Identification, repeat Gram staining from a blood agar plate, Remel BactiDrop™ Oxidase test, Urea Agar urease test and real-time PCR were used to confirm presence of Brucella and absence of Coryneform species. In case 2, repeat Gram- staining from the plate and the vials, VITEK-2 Gram-Negative Identification, real-time PCR and subculture on to Columbia agar, blood agar, and MacConkey agar were carried out to identify A. baumannii.

Results:

In case 1, initially pleomorphic Gram-positive bacteria were identified. Coryneform species were suspected. Tiny growth was observed after 24 h on blood agar plates, and good growth by 48 h. Presence of Brucella species was ultimately confirmed. In case 2, preliminary Gram-stain results suggested giant Gram-positive oval cocci. Further testing over 18-24 h identified A. baumannii.

Conclusions:

Oxidase test from the plate and urease test from the culture vial is recommended after apparent identification of pleomorphic Gram-positive bacilli from blood culture, once tiny growth is observed, to distinguish Brucella from Corynebacterium species. If giant Gram-positive oval cocci are indicated by preliminary Gram-staining, it is recommended that the Gram stain be repeated from the plate after 4-6 h, or culture should be tested in Triple Sugar Iron (TSI) medium and the Gram stain repeated after 2-4 h incubation.

Antimicrobial susceptibility pattern in nosocomial infections caused by Acinetobacter species in Asir Region, Saudi Arabia

This study aimed at evaluating the sensitivity of antibiotics towards nosocomial infections caused by Acinetobacter species. The study took place during the period Dec. 2011- Dec. 2012 at Assir Central Hospital in collaboration with the department of microbiology, college of medicine, King Khalid University, Abha. A prospective study involving 150 patients presented with nosocomial infections due to Acinetobacter species detected by bacteriological tests; direct microscopy, culture in blood agar media, fermentation test in MacConkey media and MIC (minimum inhibitory concentration) for antibiotics sensitivity using Muller Hinton media and Chemical test using API 20. A 150 nosocomial infections in this study showed gram-negative coccobacilli, non motile, glucose-negative fermentor and oxidase negative. All isolates showed 100% sensitivity to: Imipramine, Meropenem, Colistin. From the rest of tested antibiotics the higher resistant ones were; Nitrofurantoin 87% and Cefoxitin 85%. The least resistant antibiotics; Imipenem 3% and Ticarcillin 7%. While variable resistance in the rest of tested antimicrobials. A 47 patients (31.3%) have used antibiotics prior to this study. The high rate of usage occurred in elder patients. The frequency of Acinetobacter calcoaceticus baumannii complex multi-drugs resistance ABCMDR is rising including almost all commonly used antibiotics. Only few antibiotics exert 100% sensitivity towards these bacteria.

One-year surveillance of ESKAPE pathogens in an intensive care unit of Monterrey, Mexico

BACKGROUND

Bacterial species from the ESKAPE group (i.e. Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter species) are frequently resistant to antibiotics. The purpose of this study was to monitor the incidence of ESKAPE pathogens at the intensive care unit (ICU) of a tertiary care hospital in Monterrey, Mexico.

METHODS

All clinically relevant organisms isolated from June 2011 to June 2012 were included. Identification and susceptibility testing was performed using panels from Sensititre. Resistance to oxacillin, for S. aureus, and the production of extended spectrum β-lactamases (ESBLs), for K. pneumonia, were determined as defined by the Clinical Laboratory Standards Institute. Also, the presence of vanA and vanB genes was determined in E. faecium vancomycin (VAN)-resistant isolates.

RESULTS

The majority of pathogens (64.5%) isolated in the ICU unit were from the ESKAPE group. The organisms most frequently isolated were A. baumannii (15.8%) and P. aeruginosa (14.3%). A high resistance to carbapenems was detected for A. baumannii (75.3%) while 62% of S. aureus isolates were confirmed to be methicillin resistant. Of the K. pneumoniae isolates, 36.9% were ESBL producers. We detected three E. faecium VAN-resistant isolates, all of which contained the vanA gene.

CONCLUSION

The presence of the ESKAPE group of pathogens is a major problem in the ICU setting. The results of this study support the implementation of special antimicrobial strategies to specifically target these microorganisms.