Comparative Distribution of Staphylococcus Aureus Nasal Carriage in Diabetic and Non-diabetic Kenyan Populations

Abstract

Introduction: Diabetic patients are considered immunosuppressed due to their hyperglycemic state, inducing immune function dysregulation through several mechanisms. This patient cohort provides a niche for Staphylococcus aureus nasal carriage and acts as a reservoir of endogenous infections. This issue is further complicated by the increasing numbers of diabetics of pediatric and adult ages in the developing countries stemming from increased sedentary lifestyle practices. MRSA nasal carriage exacerbates this as it is associated with severe diseases such as skin and soft tissue infections and bloodstream infections, limiting treatment options and increasing morbidity and mortality. In comparison to the non-diabetics, it is deemed that nasal carriage of the offending organism in the diabetic population is higher hence a higher risk of staphylococcal infections. Objective: To explore the hypothesis that there is a difference in the Staphylococcus aureus nasal carriage proportion in diabetic and non-diabetic populations in Kenya. Methodology: This cross-sectional study enrolled two groups of participants; 189 diabetics and 189 blood donors (non-diabetics), from whom nasal swabs were collected for culturing and screening for Staphylococcus aureus and MRSA using standard clinical bacteriology techniques. The data was analyzed for carriage rates, risk factors and antimicrobial susceptibility patterns. Results: S. aureus positive diabetics accounted for 28%, while non-diabetics at 21% (p-value = 0.15). The proportion of MRSA in people with diabetes was 29% and 23% in non-diabetics. MRSA positive diabetics constituted 8% and the non-diabetics (blood donors) 5% (p-value = 0.206). Being a 36 to 55 year old diabetic was positively associated with S. aureus nasal colonization (p-value = 0.033, O.R = 2.34, 95% C.I 1.07 – 5.09). The antibiotic sensitivity patterns of selected drugs of the S. aureus isolates from diabetics relative to non-diabetics was as follows: Oxacillin (71% vs 77%), Clindamycin (77% vs 83%), Tetracycline (69% vs 75), Gentamicin (88% vs 95%), Ciprofloxacin (87% vs 88%) and Vancomycin (100% vs 100%). Of the 15 MRSA strains isolated from diabetics, 11 had different multidrug resistant combinations compared to 5 different combinations of the 9 non-diabetic MRSA isolates. Conclusion: A low prevalence of S. aureus and MRSA nasal carriage, whose differecences were not significant, was recorded in both groups. The effective management of blood glucose levels 2 could be key in lowering the nasal colonization rates in diabetics as the difference in both groups was not statistically significant. The range of various resistance patterns in the MRSA isolates in diabetics compared to non-diabetics necessitates screening and nasal decolonization policies to prevent infections of nasal origin