Etiology of ear infection and associated factors among patients attending otorhinolaryngology clinic at muhimbili national hospital

Abstract

Background: Ear infection is a global problem with high incidence in developing countries that tends to subject individual to prolonged antibiotic use which increases risks of multidrug resistant bacteria thus increase cost of treatment and decrease quality of life. Early and effective detection and management of ear infection together with knowledge of factors associated with ear infection will decrease complications that could arise. Methodology: The study was a hospital-based cross-sectional study, conducted for a period of 3 months in Otorhinolaryngology clinic at Muhimbili Nation Hospital (MNH), Tanzania. A standardized questionnaire and patient’s medical records were used to obtain participant’s social demographic, behavioural and clinical information. All the patients attending otorhinolaryngology clinic at MNH with ear complaints such as accumulation of fluid in the middle ear, bulging of the eardrum, ear pain, ear itching, perforation of the eardrum and ear discharge (otorrhea) consented or assented to participate in the study were included. Patients with other hearing disorders (congenital malformations, physical head injury, etc.) and patients who are on regular checkups were excluded. Culture and sensitivity was done. Data was stored in MS Excel program and processed by using SPSS v23. Mean and median will be used to describe continuous variables depending upon the distribution of the data. Logistic regression was used to determine the association for categorical variables. Statistical significance was defined at a p-value of < 0.05. Results: This study recruited 255 participants with a median age of 31 years (IQR: 15- 49). The majority of the participants 134 (52.5%) were males and majority had otitis externa (OE) (45.1%). 65.9% study participants who presented with ear infection had positive cultures. The overall distribution of the bacteria spp indicated that the predominant bacteria isolated were S. aureus with the frequency of 36/132(27.3%) and Pseudomonas aeruginosa with the frequency of 32/132(24.2%). Regarding fungi, Candida spp (63.8%) and Aspergillus spp (36.2%) were the most frequently isolated fungi organisms. Regarding antimicrobial susceptibility patterns, 94% of isolated bacteria were resistant to Amoxy/clav and 75.5% resistant to ceftazidime. In this study, the proportion of ESBL and MRSA were 34.4% and 47%, respectively. Furthermore the study revealed that ear infection was associated with cotton buds use (AOR 2.66, 95%CI 1.03-6.91, p 0.044), preference for cerumen impaction (AOR 13.94, 95%CI 2.93-66.33, p=0.001), preference for recurrent URTI (AOR 3.0, 95%CI 1.01-8.93, p=0.047) and nasal congestion/discharge (AOR 3.14, 95% CI 1.20-8.23, p = 0.020) Conclusion and recommendations: The present study revealed that the leading etiological agent of ear infection in our setting are bacteria; and that there is a significant proportion of Extended Spectrum Beta-Lactamase producing bacteria and Methicillin-resistant Staphylococcus aureus causing infection. In addition, ear infection was associated with recurrent URTI, nasal congestion, cotton buds use and cerumen impaction. Therefore, these findings suggest that empirical treatment should be avoided and indicate that there is a need to improve community awareness on proper ear hygiene and knowledge on cotton bud use. Also early diagnosis and treatment of URTI and cerumen impaction to prevent ear infection and the potential complications.