Serological Characterization and Antimicrobial Sensitivity Profile of Haemophilus influenzae Serotypes Isolated from Aminu Kano Teaching Hospital, Kano, Nigeria

Abstract

Aim: The aim of this research study was to isolate and serologically characterize Haemophilus influenzaeserotypes with view to determine antibiotic susceptibility profile of the isolated bacterium and compare the effectiveness of the antibiotics used on the capsulated and unencapsulated serotypes. Methodology: In this study, 200 samples from different sites (respiratory tract, blood and cerebrospinal fluid) were collected from patients 1—70 years old and were cultured on chocolate agar. The presence of encapsulated bacteria was identified by Fildes medium, Congo red staining and Slide Agglutination test. Serotyping was performed by Slide Agglutination test. Results: The results showed that 14 (7.0%) cases were positive for Haemophilus influenzae of which 78.5% were encapsulated. A statistical relationship was found between unencapsulated H. influenzae and the age of the subjects. No significant differences were found between the incidence of the infections caused by the bacterium and the gender. Isolates were sensitive to Levofloxacin (85.7%), Azithromycin and Clarithromycin both by (71.4%). While, moderate sensitivity was found in Amoxicillin (28.6) and Co-trimoxazole (28.6) with least sensitivity rates in Cloxacillin (7.1) and Tetracycline (0). Unencapsulated strains were found to be more sensitive to the tested antimicrobials than their encapsulated counterparts. Conclusion: Our research showed that age is among the risk factors for H. influenzae infections and unencapsulated strains were found to be more prevalent in the diagnosed sites.