Microbial profile of infections amongst adult in-patients in selected intensive care units in Port Harcourt: a comparative study

Background: The intensive care unit should maintain a minimal presence of pathogenic organisms that could potentially lead to severe infections, particularly in an environment where numerous procedures and interventions compromise the body's normal mucosal defenses. Aim: To evaluate the prevalence and distribution of common and clinically relevant microorganisms within selected Intensive Care Units (ICUs) in Port Harcourt, Nigeria. Methods: A prospective, non-randomized study covering January 2022 to December 2024. The study sites were the intensive care units of three hospitals in Port Harcourt: namely the University of Port Harcourt Teaching Hospital (UPTH), Sterling Specialist Hospital, and Prime Medical Consultants. Clinical specimens, including blood samples, urine specimens, respiratory secretions, wound swabs, and venous catheter tips, were collected and analyzed. Data were analyzed using SPSS version 25. Results: Of the 238 specimens, 186 (78.8%) yielded positive cultures. Gram-negative bacteria (GNB) constituted 68.29% of isolates, followed by Gram-positive bacteria (23.66%) and fungi (8.06%). The most frequently isolated microorganisms were Klebsiella pneumoniae (23.12%), Escherichia coli (19.36%), Pseudomonas aeruginosa (14.52%), Proteus mirabilis (8.60%), and Enterobacter cloacae (2.69%). Among Gram-positive bacteria, methicillin-resistant Staphylococcus aureus (MRSA) accounted for 15.59% of cases, while Streptococcus species constituted 8.07%. Fungal infections accounted for 8.06% and were represented by Candida albicans (5.91%) and non-albicans Candida species (2.15%). UPTH recorded the highest microbial burden, particularly with multidrug-resistant pathogens, compared to the private hospitals. Conclusion: The study revealed a marked variation in antimicrobial resistance patterns among hospitals, with public hospital demonstrating a notably higher rate of multidrug-resistance in comparison to private hospitals.