Acanthamoeba- Associated Pseudomonas Species At Kenyatta National Hospital Intensive Care Unit, Kenya

Abstract

Background: Free-living amoeba (FLA) such as Acanthamoeba spp. are ubiquitous unicellular eukaryotes that graze on bacteria, viruses, algae and are common contaminants in virtually all environments. However, amoeba resistant microorganisms (ARMs) evade amoebic killing and survive and multiply within FLA. Pseudomonas spp. is an ARM with known high antibiotic resistance, increased virulence, resistance to disinfectants and are etiologic agents of nosocomial infections. Co-existence of FLA and ARMs may perpetuate spread of pathogens across hospital environments that would be responsible for nosocomial infections and the antimicrobial resistance global surge today. Sensitization on the existence of ARMs and their potential impact on infection control and patient health is paramount. Aim:To culture and isolate both Acanthamoeba spp. and bacteria as well as to detect Pseudomonas sp. genomic DNA within Acanthamoeba spp. isolates obtained from swabs collected from selected surfaces and equipment at Kenyatta National Hospital Intensive Care Unit (KNH ICU). Methodology: This was a descriptive cross-sectional study done at KNH ICU. One hundred and fifty-three swabs were collected in duplicate (306 swabs). Acanthamoeba spp. cultures were performed on the first batch of 153 swabs while bacterial cultures were performed on the second batch of 153 swabs. Pseudomonas sp. genomic DNA was detected from Acanthamoeba spp. isolates using polymerase chain reaction (PCR) technique. Results: The proportion of swabs with Acanthamoeba spp. isolates was 93.5% (143/153). Subcultures were done on 62.7% (96/153) primary Acanthamoeba spp. isolates and only 22.9% (22/96) were positive. PCR was conducted on all the 22 positive Acanthamoeba spp. subcultures and Pseudomonas sp. genomic DNA was detected in almost half (45.5%) of the tested subcultures. Of the total bacterial isolates, the proportion of Pseudomonas spp. was 10.7% (18/168). Conclusion: To the best our knowledge Acanthamoeba spp. was for the first time in Kenya isolated upon culture and Pseudomonas sp. endosymbiotic relationship with the isolated Acanthamoeba spp. confirmed as a potential contributor to nosocomial infections and bacterial antimicrobial resistance burden at KNH ICU.