DESIGN: Forty-four full-term healthy neonates (17 males and 27 females) participated in a longitudinal study. The neonates were assessed at 1-month intervals from 0 to 6 months of age using high-frequency tympanometry, acoustic stapedial reflex, distortion product otoacoustic emissions, and pressurized WBA. The values of WBA at tympanometric peak pressure (TPP) and 0 daPa across the frequencies from 0.25 to 8 kHz were analyzed as a function of age.
RESULTS: A linear mixed model analysis, applied to the data, revealed significantly different WBA patterns among the age groups. In general, WBA measured at TPP and 0 daPa decreased at low frequencies (<0.4 kHz) and increased at high frequencies (2 to 5and 8 kHz) with age. Specifically, WBA measured at TPP and 0 daPa in 3- to 6-month-olds was significantly different from that of 0- to 2-month-olds at low (0.25 to 0.31 kHz) and high (2 to 5 and 8 kHz) frequencies. However, there were no significant differences between WBA measured at TPP and 0 daPa for infants from 3 to 6 months of age.
CONCLUSIONS: The present study provided clear evidence of maturation of the outer and middle ear system in healthy infants from birth to 6 months. Therefore, age-specific normative data of pressurized WBA are warranted.
METHODS: A case-control study was carried out among patients with CSOM (cases) and controls were those with no ear pathology. The presence of CSOM was made through a medical history and otoscopic examination. Allergen testing was done by the skin prick test.
RESULTS: In all 124 subjects were recruited in this study with equal number of the cases and controls. The commonest positive reaction in the skin prick test in both groups was to house dust mites. Among CSOM cases, half (50%) of them had an allergy to Blomia tropicalis and 48.4% to Dermatophagoides while in the control group, 27.4% to Dermatophagoides and 25.8% to B. tropicalis. There were significant associations between CSOM and allergy to B. tropicalis (p=0.005), Dermatophagoides (p=0.016) and Felis domesticus (p=0.040). The prevalence of allergy at 95% confidence interval (95%CI) in CSOM and control groups were demonstrated as 59.7% (95%CI: 47.5, 71.9) and 30.6 % (95%CI: 19.1, 42.1) respectively. There was a significant association between allergy and CSOM (p=0.001).
CONCLUSION: Indoor allergens are the most prevalent in our environment and therefore good control may difficult to achieve. The hypersensitivity states of the subject are likely to have a role in the pathogenesis of CSOM especially in the tropical countries where allergy occurs perennially.