Comparison of nasopharyngeal bacteriological profile between patients with diabetes and healthy individuals in Accra, Ghana.

Background: The nasopharynx is characterised by a rich microbial diversity, making it an important endogenous reservoir for respiratory infections. People living with diabetes (PLWD) have a high risk for acquisition of respiratory tract infections, but their nasopharyngeal bacterial flora have rarely been investigated.

Aim: To investigate the nasopharyngeal bacterial flora among PLWD and non-diabetics at the Korle Bu Teaching Hospital in Accra.

Methodology: This study was a case-control one, involving 130 each of PLWD and non-diabetics. Nasopharyngeal swab specimens were obtained from the participants and cultured for bacteria, which were identified using MALDITOF mass spectrometry.

Results: The bacterial flora present in the anterior nares of the participants of both study groups was characterised by a rich diversity, comprising both Gram-positives and Gram-negatives. In the diabetics, the dominant bacteria were Acinetobacter baumannii (19.6%), Staphylococcus epidermidis (18.12%), Staphylococcus aureus (15.2%), and Rahnella aquatilis (12.3%). In the control group, however, the dominant bacteria were Staphylococcus epidermidis (21.9%), Staphylococcus aureus (19.0%), Proteus mirabilis (10.9%), Pseudomonas aeruginosa (10.2%), Acinetobacter baumannii (8.8%), and Enterobacter cloacae (7.2%). Between groups, Acinetobacter baumannii (19.6% vs. 8.8%, p = 0.014) and Rahnella aquatilis (12.3% vs. 0.0%, p < 0.001) recorded a significantly higher prevalence in the diabetes group than in the control group. On the contrary, Klebsiella pneumoniae (0.0% vs. 4.4%, p = 0.003), Proteus mirabilis (2.2% vs. 10.9%, p = 0.006), and Pseudomonas aeruginosa (0.7% vs. 10.2%, p < 0.001) had significantly lower prevalence than in the control group.

Conclusion: The nasopharyngeal bacterial flora of PLWD in Accra seems to have comparable diversities with those of non-diabetics. Nonetheless, the PLWD had a higher carriage rate of Acinetobacter baumannii but seem to have some protection against carriage of Klebsiella pneumoniae, Proteus mirabilis, and Pseudomonas aeruginosa.