Secretory Otitis Media (SOM) is a group of non-purulent (no pus), sterile (no infection) middle ear fluid in which there is no perforation of the TM. It is very common in childhood, often unnoticed for long periods and can therefore, result in significant problems when the child grows up, such as chronic conductive hearing loss, developmental delay in speech and language and learning difficulties (1). Although the mechanisms underlying SOM are complex and not fully understood, it is thought to be due to Eustachian tube dysfunction, immune-mediated inflammatory reactions and the development of viral and bacterial biofilms. (2) The Eustachian tube is shorter, more horizontal and less stiff in children, thus drainage and ventilation of the middle ear are more impaired. (3, 4)

SOM prevalence and determinants can differ substantially between various populations and geographic regions, depending on genetic, environmental and socioeconomic differences.(5, 6) Demographic factors such as age/sex, socioeconomic status and parental education have been found to impact on the incidence and natural history of the disease.(7) Further, the relationship between breastfeeding vs bottle feeding and environmental tobacco smoke and otitis media has been consistently linked.(8) Another important clinical variable which is related to treatment and prognosis is laterality (unilateral/bilateral). Sometimes unilateral disease will clear up, but bilateral disease is more likely to be chronic and lead to significant hearing loss that will require surgery for insertion of ventilation tubes.(9, 10) There is a lack of comprehensive epidemiological data on SOM in Pakistan especially in the province of KP.(11) The disease pattern is also restricted in the region due to current demands: there are limited access to specialized healthcare services and low health literacy, high consanguinity rates and high poverty rates in the region that could potentially alter the disease pattern.(12) Though relatively developed in the region, Abbottabad is still facing these challenges at primary health care level. The department of ENT, Head and Neck Surgery, Ayub Teaching Hospital, Abbottabad is a referral center for the surrounding population which made it ideal for such a study.(13) Knowing the local determinants and patterns of laterality plays an important role in the identification of context-specific preventive measures and the best use of scarce health services. This study therefore aims at filling this knowledge gap and to provide a systematic analysis of the demographic profile and laterality of the disease in children with SOM in Ayub teaching hospital MTI, Abbottabad in 2023-2024.

Study Design and Setting This descriptive cross-sectional study was carried out at Department of ENT, Head and Neck Surgery, Ayub teaching Hospital MTI, Abbottabad from 5th January, 2023 to 28th December, 2024. Ayub teaching Hospital MTI Abbottabad is a big tertiary care specialty hospital & referral center for the population of Abbottabad district and its surrounding areas of Khyber Pakhtunkhwa province of Pakistan. The ENT department of the hospital offers the specialties of otolaryngology, offers a large number of ENT patients both in the city as well as the countryside and therefore it was an ideal venue for such an epidemiological investigation. Study population and sampling technique. All children aged between 1 – 12 years, who received a new diagnosis of secretory otitis media in the outpatient department of ENT and as an in-patient at the hospital during the study period were included. A non-probability consecutive sampling technique was used to select participants. All patients with the inclusion criteria in the study period were included until 50 patients were attained. The number of samples was determined by feasibility of recruiting samples for the study duration and the descriptive study. Inclusion Criteria Of any gender, all children aged 1-12 years. Patients with a new diagnosis of secretive OM confirmed. The diagnosis was confirmed by clinical exam findings which were supportive of SOM. Tympanometry (Type B or Type C curve) confirmation of diagnosis. Informed consent of parent/guardian to participate. Exclusion Criteria Children with ear and face defects or defects of the head. Immunodeficiency or immunosuppressive diseases in the past. A previous ear surgery or history of ear tube placement. Acute otitis media (AOM) - perforated or purulent OM. Systemic diseases that have a long onset period such as diabetes mellitus, renal disease or malignancies. Children that received antibiotic/immunosuppressive medication (within 2 weeks before). Parents/guardians who have not given informed consent. Diagnostic Procedures A consultant ENT surgeon (at least 5 years’ experience in pediatric otolaryngology) attended to all children, carrying out a full examination of the ears. History was taken and examination was done of the anterior rhinoscopic examination, oropharynx to see if there was any other upper respiratory disease. Otoscopic examination was performed using an otoscope fitted with a pneumatic attachment which was used to assess the mobility of the TM. Color of the TM (normal, dull, amber or hyperemic), mobility (normal, reduced or absent), position of the TM (neutral, retracted or bulging) and presence or absence of fluid level and/or air bubbles were all assessed. The diagnosis of SOM was achieved by checking the mobility of the TM using pneumatic otoscopy, and confirmed when it was dull or retracted and had little or no mobility and was not associated with any signs of acute TM inflammation (pain, fever or purulent discharge). Clinical Examination All of the patients were then tested for tympanometry using a standard impedance audiometer to confirm the diagnosis. The Jerger classification system (Type A, normal; Type B, flat curve (MEE); or Type C, negative pressure (ETD)) was used to interpret the tympanometry. Only patients with Type B curves and C curves were studied. Pure tone audiometry was used to determine the degree of hearing loss, but it was not used as a diagnostic test, but as indication for baseline audio logical evaluation, for children aged 4 years or older. Laterality Assessment Laterality of the disease was established by clinical and tympanometric examination of each ear. Cases were defined as either unilateral (single ear) or bilateral (both ears). In unilateral cases, a notation of right or left was made for the affected side. All the ENT physicians made this classification independently and in any case of discrepancy, a re-evaluation of the patient was conducted together and settled by consensus. Data Collection The information for this study was obtained from a structured and pre-tested questionnaire. The questionnaire was translated into English and Urdu languages to ensure that the data were collected accurately and it was pre-tested with 10 patients for clarity, comprehensibility and reliability before the study. The instrument was administered a last time requiring some necessary modifications given the results of the pilot administration of the instrument. The questionnaire consisted of two parts as follows: Data analysis All the data gathered were entered into a pre-designed Microsoft Excel spreadsheet (version 2019) with data entry validation checks that were prepared to minimize the data entry error. The data then was cleaned for inconsistencies, missing data and outliers and exported into SPSS version 25.0 (IBM Corp., Armonk, NY, USA) for further statistical analysis. All questionnaires that were not completed and/or incomplete were checked and wherever possible corrected by follow-up with parents/guardians of the participants. Data were kept on a password-protected computer access to which is limited to the principal investigator for the security and confidentiality of the data. The resulting data set was anonymised in that all personal information was removed. Statistical Analysis All the study variables were presented by descriptive statistics. The categorical variables (gender, age groups, socioeconomic status, feeding practices, education level, and disease laterality) were reported as frequencies and percentages. Age (in years) was represented as mean and SD, as a continuous variable. For the categorical variables, their association with various demographic and risk factors and disease laterality (bilateral vs. unilateral) was explored using the chi-square test. Fisher's exact test was performed for the cases where the expected numbers of cells were less than 5. The p value was < 0.05 considered statistically significant for all analyses. The direction of the test result on each of the statistical tests was not given, as the tests were two-tailed tests. These were then compiled and plotted to display and analyze the data. Ethical Considerations The parents/legal guardians of all children who participated provided written informed consent, after receiving a detailed description of the purpose, procedures, potential risks, and benefits of the study. The participants were informed that their information would be kept confidential and that any information which could identify them would be omitted from the final data set. There was a free consent to participate of the parents, and parents had the freedom to withdraw their child from the study at any time without impacting their access to medical care. No other use was made except for routine diagnostic evaluation; no invasive procedure was performed. Ethical principles from the Declaration of Helsinki were followed.

The data obtained from 50 children with secretory otitis media were analyzed. The following tables summarize the demographic characteristics and laterality patterns.

Table 1: Demographic Profile of the Study Population (n=50)

Table 2: Laterality and Associated Clinical Parameters (n=50)

Table 3: Association of Laterality with Demographic Factors

The results of this cross sectional study offer very important insight in to the demographic factors and laterality pattern of pediatric secretory otitis media in Abbottabad area. The study group had a definite age bias that was very evident, with a disproportionately high number of cases (68%) falling within the age range 1-5 years. This matches the internationally accepted epidemiologic profile of SOM that has been identified as occurring most frequently at between 6 months to 4 years of age. This immaturity of the Eustachian tube is primarily blamed on the anatomical and functional immaturity of the tube, being shorter, more horizontal, and less stiff than in adults, making it less effective in ventilating and draining the middle ear.(3) Mechanical obstruction of the tubal orifice is predisposing to the occurrence of effusion, because of the rapid growth of the lymphoid tissue around this age and especially the adenoids.(14) Children aged >6 years were relatively less in proportion, reflecting the age-dependent improvement in Eustachian tube function as a result of the growth of the craniofacial skeleton.(15) One interesting finding in our study was the association between socioeconomic status (SES) and disease prevalence. More than 60% of the patients were low income and this group was significantly larger in the bilateral disease group (71%). There is a strong association that likely is mediated by a set of related factors. Poor SES is frequently associated with poor housing conditions that enable the easy spread of respiratory infections. This is compounded by increased risk for poor nutritional status that can impair immune function and susceptibility to infections. In addition, parents of lower SES status may lack health literacy, and may avoid seeking medical attention, thereby giving the disease a chance to progress to a bilateral and more chronic state(16). The specific association of low SES with bilateral disease is clinically important to raise awareness since children from disadvantaged backgrounds could have a greater disease burden requiring more aggressive treatment. This is an indication of the need for a targeted approach, in which public health interventions offer affordable health care and raise awareness of the lower-income population of the early symptoms and potential long-term consequences of SOM.(17) Parental education was another important finding in our study; more than half of the children had an illiterate or only primary-level education. Educated mothers are more likely to make use of the preventive health care, to be aware of the early signs of sickness and to be aware of proper feeding and hygiene practices. However, mothers with limited education may not recognize the less obvious symptoms of SOM like a hearing problem or a speech delay, which are commonly mistaken for behavioural shortcomings in the child. They may also be unaware of the importance of exclusive breastfeeding and of the dangers to be avoided from using bottles. (18) This study revealed that bottle-feeding was much more prevalent than breast-feeding (62%), and that there was a strong association with bilateral disease. This is in line with the work of others that has shown that infant bottle feeding has been linked to the decreased protection from the protective immunoglobulins and antibodies in breast milk and increased risk of reflux up the Eustachian tube and bacterial colonization of the ear, which significantly increases the risk of otitis media. This study also confirmed that recurrent upper respiratory tract infections (URTIs) were an extremely important predisposing factor, as most patients were found to have a history of frequent URTIs (82%). The importance of mucosal inflammation and edema under viral infection in the nose, throat, and Eustachian tube, which leads to decreased mucociliary clearance in the middle ear is well established.(19) This results in transudation of fluid and effusion formation. Recurrent URTIs were significantly associated with bilateral involvement, indicating that infection is likely to play a large role in the development of more extensive middle ear pathology.(20) Primary prevention of SOM is possible by implementing public health measures to reduce the incidence of URTIs, including increasing hand hygiene, reducing crowding and emphasizing immunization.(21) Alarmlingly high (44%) was the percentage of patients exposed to passive smoking, a risk factor that is modifiable, and has been shown to have negative effects on respiratory health and to cause irritation of the mucosa of the Eustachian tube. Rigorous anti-smoking initiatives and parental advice about house environmental smoke dangers are very much needed.(22) Regarding the laterality of the disease, in 62% of the cases, it was bilateral, a higher percentage than in some previous regional studies. This bilateral disease rate is significant and has implications for patient management. Bilateral SOM is more likely to result in significant hearing loss and if that persists can have a significant effect on a child's learning, speech development and social interaction. This frequently requires more definite, timely and/or surgical interventions such as tympanostomy tube placement.(23) The unilateral cases, on the other hand, were nearly double (38%) compared to the bilateral cases; the left ear was more affected than the right in the unilateral cases (63.2% vs. 36.8%). This left-sided predominance has been described in other studies and the mechanism is still unknown, although there have been several speculations. The theory is that the left Eustachian tube is frequently positioned more horizontally and/or may have a more narrow angle of inclination, making it more vulnerable to dysfunction.(15) The other one is sleeping position: many babies and young children prefer to sleep on their right side, which allows the right ear to drain better, and puts the left ear at risk of fluid pooling and bacterial growth.(24) Further studies are needed to verify this laterality tendency but the clinician should have a high index of suspicion for disease to be left sided if unilateral disease is suspected.

The age group most common with secretory otitis media in Abbottabad is less than 5 years present showing slight male predominance, with bilateral involvement of ears occurring in almost two-thirds of cases. The unilateral cases reveal a clear predominance of the left side, which is an interesting clinical finding that needs to be explored further. Recurrent upper respiratory tract infections, low socioeconomic status and maternal illiteracy are important modifiable risk factors associated with the disease, as is bottle-feeding. The results highlight the importance of routinely including otological screening in primary care and community-based parent education programmes. To minimize disease burden and to prevent long term complications to the ears and child development, early detection and precise public health interventions are crucial in this at-risk group.

Limitations

Our study is limited by the small number of patients (50) studied, which makes our results less generalizable to the pediatric population in the area. It is not possible to determine the causal relationships between the risk factors identified and disease development in the cross-sectional study design. There may be recall bias because other historical information, including feeding practices and type of infections, are dependent upon parental recall. This study was done at only one tertiary care center, which could have led to selection bias and overlooked milder or sub clinical community cases. This study did not gather any information about several important confounding variables, such as detailed vaccination history or information about pollution in indoor air.

Recommendations

All children less than 5 years old should be routinely screened for SOM during Expanded Program on Immunization (EPI) visits. It is important that community-based health education program to mothers focus on exclusive breastfeeding and risks of bottle-feeding and passive smoking. Increased early recognition and referral would be greatly enhanced by training primary care physicians and LHWs in pneumatic otoscopy and basic tympanometry. Strategies that can be implemented to prevent the occurrence of URTIs should be prioritized, such as promoting vaccination and hand hygiene. In order to definitively establish risk factors and developmental outcomes over the long-term in affected children, larger, multi-center, prospective cohort studies are needed.

1. Troyan V, Pukhlik S, Titarenko O, Kostrovskyi О, Sinaiko І, Lobova О. Otorhinolaryngology. 2020.
2. Mather MW, Powell S, Talks B, Ward C, Bingle CD, Haniffa M, et al. Dysregulation of immune response in otitis media. Expert reviews in molecular medicine. 2021;23:e10.
3. Goulioumis AK, Gkorpa M, Athanasopoulos M, Athanasopoulos I, Gyftopoulos K, Athanasopoulos M. The eustachian tube dysfunction in children: anatomical considerations and current trends in invasive therapeutic approaches. Cureus. 2022;14(7).
4. Bal R, Deshmukh P. Management of Eustachian tube dysfunction: A review. Cureus. 2022;14(11).
5. Choffor‐Nchinda E, Bola Siafa A, Nansseu JR. Otitis media with effusion in Africa‐prevalence and associated factors: A systematic review and meta‐analysis. Laryngoscope investigative otolaryngology. 2020;5(6):1205-16.
6. Jamal A, Alsabea A, Tarakmeh M. Effect of ear infections on hearing ability: a narrative review on the complications of otitis media. Cureus. 2022;14(7).
7. Bhatia R, Singh M, Pradhan P. Trends in health equity and access among children with otitis media in India: A systematic review. Journal of Pediatric Pulmonology. 2022;1(3):87-92.
8. Hardani AK, Esfandabadi FM, Delphi M, Samir MA, Abdollahi FZ. Risk factors for otitis media in children referred to Abuzar Hospital in Ahvaz: a case-control study. Cureus. 2020;12(8).
9. Principi N, Esposito S. Unsolved problems and new medical approaches to otitis media. Expert Opinion on Biological Therapy. 2020;20(7):741-9.
10. Popovych V, Orishchak O. State of hearing function and eustachian tonsils in patients with secretory otitis media at different stages of its development. Art of Medicine. 2022:142-8.
11. Naz I. Assessment of antimicrobial activity of cerumen (earwax) and antibiotics against pathogenic bacteria isolated from ear pus samples. Microbiology Research. 2020;11(1):5.
12. Pang K, Di Y, Li G, Li J, Li X, Sun L. Can reflux symptom index and reflux finding score be used to guide the treatment of secretory otitis media in adults? ORL. 2020;82(3):130-8.
13. Shah SMH, Mahmud A, Shad S, Farooq A, Shahnawaz A, ul Ehsan HR. DISTRIBUTION AND DETERMINANTS OF ORAL SQUAMOUS CELL CARCINOMA: A RETROSPETIVE OBSERVATIONAL STUDY AT ORAL & MAXILLOFACIAL DEPARTMENT OF AYUB TEACHING HOSPITAL ABBOTTABAD. Pakistan Oral & Dental Journal. 2021;41(3):159-64.
14. Clarke RW. Diseases of the Ear, Nose & Throat in Children: An Introduction and Practical Guide: CRC Press; 2022.
15. Holmes GJ. Developmental characterisation of the temporal bone: Quantifying the growth of the eustachian tube and mastoid in Australian subadults: Queensland University of Technology; 2022.
16. Rook GA. Evolution, the immune system, and the health consequences of socioeconomic inequality. Msystems. 2022;7(2):e01438-21.
17. Perdrizet J, Farkouh RA, Horn EK, Hayford K, Sings HL, Wasserman MD. The broader impacts of otitis media and sequelae for informing economic evaluations of pneumococcal conjugate vaccines. Expert review of vaccines. 2022;21(4):499-511.
18. Campbell L, Reath J, Hu W, Gunasekera H, Askew D, Watego C, et al. The socioemotional challenges and consequences for caregivers of Aboriginal and Torres Strait Islander children with otitis media: A qualitative study. Health Expectations. 2022;25(4):1374-83.
19. Karamert R, Tapısız AA, Konstantinidis I. Pathophysiology of Pediatric Ear, Nose, and Throat Infections. Pediatric ENT Infections: Springer; 2021. p. 19-27.
20. Folino F, Ruggiero L, Capaccio P, Coro I, Aliberti S, Drago L, et al. Upper respiratory tract microbiome and otitis media intertalk: lessons from the literature. Journal of Clinical Medicine. 2020;9(9):2845.
21. Ellwanger JH, Byrne LB, Chies JAB. Examining the paradox of urban disease ecology by linking the perspectives of Urban One Health and Ecology with Cities. Urban ecosystems. 2022;25(6):1735-44.
22. Ferrante G, Cilluo G, La Grutta S. Prevention and cessation of smoking. Paediatric Respiratory Medicine. 2021:815.
23. Núñez-Batalla F, Jáudenes-Casaubón C, Sequí-Canet JM, Vivanco-Allende A, Zubicaray-Ugarteche J. Early diagnosis and treatment of unilateral or asymmetrical hearing loss in children: CODEPEH recommendations. Acta Otorrinolaringologica (English Edition). 2020;71(1):45-55.
24. i Brú JdlF. Upper respiratory tract infections-2: otitis media (etiology, symptoms and diagnosis; complications and treatment); recurrent acute otitis media and chronic otitis media; external otitis. Pediatría Integral. 2022;352:353-68.