Emergence of Raoultella ornithinolytica isolated from chicken products in Alexandria, Egypt

Emergence of NDM-1-producing Raoultella ornithinolytica from reservoir water in Northeast Thailand

Background and Aim

Antibiotic resistance is a major global health threat. The increasing prevalence of drug-resistant bacteria poses a serious challenge to the effective treatment of infections in both humans and animals. Water is a major source of human and animal exposure to bacteria, and the presence of drug-resistant bacteria in water could present a severe threat to public health and animal production. This study investigated the presence of drug-resistant bacteria in Lam Pao Dam (LPD) water in Kalasin, Thailand.

Materials and Methods

Ampicillin-resistant strains were obtained from LPD water and identified using 16s rDNA sequencing. Antibiotic resistance genes were detected by polymerase chain reaction using specific primers. The presence of antibiotic-resistant bacteria was evaluated using 16s amplicon analysis. The minimum inhibitory concentration (MIC) of Raoultella ornithinolytica strains against antibiotics was determined.

Results

A total of 12 R. ornithinolytica, 4 Bacillus cereus, and 4 Enterococcus faecalis isolates were resistant to ampicillin. Almost all R. ornithinolytica strains harbored blaSHV and blaOXA genes, and two strains also harbored the blaNDM-1 gene. All four E. faecalis strains harbored the blaIMP gene. The most abundant species in the LPD sample was Exiguobacterium indicum, followed by E. faecalis and R. ornithinolytica. The MICs of 10 R. ornithinolytica strains against five antibiotics revealed that all strains were resistant to ampicillin but susceptible to meropenem, doripenem, ertapenem, and imipenem.

Conclusion

These findings suggest a high prevalence of drug-resistant bacteria in LPD water. This is a cause for concern, as it could spread antibiotic-resistant infections in the community.

Insights to antimicrobial resistance: heavy metals can inhibit antibiotic resistance in bacteria isolated from wastewater

The alarming upsurge in the co-existence of heavy metal and antibiotic resistance may have a devastating impact on humans, animals, and the environment. Four metal-resistant bacteria were isolated from hospital effluents and industrial drain. Heavy metal resistance and antimicrobial resistance were examined in the isolates followed by identification through 16S rRNA gene sequencing. Delftia tsuruhatensis strain FK-01 and Carnobacterium inhibens strain FK-02 tolerated arsenic with maximal tolerated concentration (MTC) of 30 mM and 10 mM, respectively. Staphylococcus hominis strain FK-04 tolerated copper up to 4 mM and lead-resistant Raoultella ornithinolytica strain FK-05 exhibited tolerance to 1 mM lead. The growth kinetics of bacteria were monitored in the presence of metals and the following antibiotics, tetracycline, chloramphenicol, and kanamycin. The presence of arsenate significantly enhanced tetracycline resistance in C. inhibens. Heavy metal-induced antibiotic resistance was also observed in S. hominis and R. ornithinolytica, against chloramphenicol and tetracycline respectively. D. tsuruhatensis showed resistance to kanamycin but when grown in the presence of arsenic and kanamycin, bacteria lost resistance to the antibiotic. Therefore, it is suggested that the novel arsenate-resistant strain Delftia tsuruhatensis FK-01 has a unique ability to inhibit antimicrobial resistance that can be harnessed in bioremediation.

Sepsis From Multisystem Infection With Multidrug-Resistant Raoultella ornithinolytica

Raoultella (R.) ornithinolytica is a gram-negative, encapsulated aerobe or facultative anaerobe belonging to the family Enterobacteriaceae. It is distinguished from other members in the family with a negative indole test, growth at 10^oC, production of histamine, a negative D-melezitose test, and metabolism of ornithine. R. ornithinolytica is a versatile organism found in different habitats, including soil, water, and plants, as well as colonizing the human gastrointestinal tract and throat. It was considered to cause opportunistic infection in humans but is increasingly being implicated in infections in immunocompetent individuals. Raoultella ornithinolytica causes infection in different clinical settings. Sepsis from Raoultella ornithinolytica is increasing among humans, and it is considered an emerging infectious agent in both immunocompromised and immunocompetent people. There is an increasing level of antibiotic resistance among isolates with reports of multidrug resistance.

We report the case of a 95-year-old man with multidrug-resistant R. ornithinolytica multisystem infection and review the literature.

Bacteriological profile, antibiotic susceptibility and factors associated with neonatal Septicaemia at Kilembe mines hospital, Kasese District Western Uganda

Introduction

Neonatal septicaemia is one of the most common leading causes of neonatal morbidity and mortality in developing countries. It is estimated to affect more than 30 million people worldwide annually, potentially leading to 6 million deaths.

Objective(s)

To determine the prevalence, bacteriological profile, antibiotic susceptibility and factors associated with neonatal septicaemia among neonates suspected to sepsis at Kilembe mines hospital.

Methods

We conducted a descriptive cross-sectional study, where purposive sampling technique was used and blood was drawn from 122 neonates suspected to sepsis attending Kilembe Mines Hospital during the period (July to November 2020). Specimens were inoculated in Brain heart infusion broth, transported to Fortportal Regional Referral Hospital, plated daily up to 7 days on blood, chocolate, MacConkey agar and incubated in aerobic and 5% carbondioxide. Pure colonies were identified by Gram stain, biochemical tests and antibiotic sensitivities obtained by Kirby Bauer disc diffusion method. Associations were tested using Chi square with Fisher’s exact or Yates correction tests where necessary and statistical significance was set at P < 0.05. Stata (version 14) used for statistical analysis.

Results

Blood cultures were positive in 59.0% cases with 55.5% male and 44.4% female. EOS was present in 56.9% and LOS 43.1% of the cases. Gram negative (56.9%) organisms were most implicated with neonatal septicaemia than Gram positives ones (43.1%). Gram positive organisms exhibited better susceptibility to amikacin, linezolid and vancomycin but more resistant to ampicillin and gentamicin. Of the aminoglycosides, amikacin exhibited a verge over netilmicin and gentamicin against Gram negative isolates. Risk factors of neonatal septicaemia were mother’s age of ≥25 years, employed mothers, tertiary-level of education, SVD, ANC attendance of ≥4 times, UTI during pregnancy, PROMS, foul Smelling liquor, urban residence, neonatal birth weight of ≥2500 g, Apgar score 1st and 5th min ≥6 and resuscitation.

Conclusion

Multi-drug resistant organisms were isolated. Therefore caution is required in selection of antibiotic therapy and avoid empirical treatment.

A spotlight on Raoultella ornithinolytica: A newly emerging life-threatening zoonotic pathogen

The genus Raoultella contains Raoultella ornithinolytica (R. ornithinolytica), which was previously named as Klebsiella ornithinolytica. R. ornithinolytica is a Gram-negative bacillus that belongs to the family Enterobacteriaceae. This pathogen is normally present in aquaculture, and it has been isolated from fish, insects, and wild and domestic birds. Seafood and poultry products are incriminated as sources of R. ornithinolytica infection. Community-acquired human infection with R. ornithinolytica is common. This infection is commonly associated with sepsis, bacteremia, food poisoning, purities, and urinary and respiratory tracts' infections. Rapid acquired resistance of R. ornithinolytica strains is common, and it is related to the development of resistant genes. R. ornithinolytica is considered as a newly emerging life-threatening pathogen world-wide. Hence, it is very important to determine the role of animals and birds in the epidemiological situation of this pathogen as well as the detection of antibiotic resistance genes before treatment.