Identification of pathogens isolated in acute external otitis cases and evaluation of aminoglycoside and quinolone sensitivity

ObjectiveThis study aimed to identify pathogens isolated in acute external otitis cases and determine their distribution according to ages and seasons as well as investigate the susceptibility or resistance to the aminoglycoside and quinolone group antibiotics of which topical forms are available.MethodA total of 168 patients diagnosed with acute external otitis were evaluated retrospectively. Growing bacteria were identified according to the species by conventional methods. Antibiotic susceptibility status was determined for the growing bacteria.ResultsThe most common bacteria detected were pseudomonas group bacteria (38.7 per cent). Resistance to the amikacin group of antibiotics was found to be the lowest and resistance to the ciprofloxacin group of antibiotics was the highest.ConclusionExternal auditory canal cultures should be taken simultaneously with empirical treatment. Seasonal effect and age group should be taken into consideration in the choice of treatment and after questioning about chronic exposure to water. Empirical treatment should then be started.

Diagnosing necrotizing external otitis on CT and MRI: assessment of pattern of extension

Background and purpose Necrotizing external otitis (NEO) is a serious complication of external otitis. NEO can be classified according to—anterior, medial, posterior, intracranial, and contralateral—extension patterns. Currently there is no consensus on the optimal imaging modality for the identification of disease extension. This study compares NEO extension patterns on MR and CT to evaluate diagnostic comparability. Methods Patients who received a CT and MR within a 3-month interval were retrospectively examined. Involvement of subsites and subsequent spreading patterns were assessed on both modalities by a radiologist in training and by a senior head and neck radiologist. The prevalence of extension patterns on CT and MR were calculated and compared. Results All 21 included NEO cases showed an anterior extension pattern on CT and MR. Contrary to MR, medial extension was not recognized on CT in two out of six patients, and intracranial extension in five out of eight patients. The posterior extension pattern was not recognized on MR. Overall, single anterior extension pattern (62%) is more prevalent than multiple extension patterns (38%). Conclusion All anterior NEO extension pattern were identified on CT as well as MR. However, the medial and intracranial spreading patterns as seen on MR could only be identified on CT in a small number of patients. The posterior spreading pattern can be overlooked on MR. Thus, CT and MR are complimentary for the initial diagnosis and work-up of NEO as to correctly delineate disease extent through the skull base.

Antimicrobial activity of essential oils against positive coagulase Staphylococcus isolated from External Canine Otitis cases

This study aimed to evaluate the antimicrobial activity of clove (Syzygium aromaticum), citronella (Cymbopogon winteranius) and melaleuca (Melaleuca alternifolia) essential oils (EOs) on CoPS. Of the 67 cerumen samples collected, 17 CoPS strains were isolated. Using the microdilution method in a 96-well plate, EOs were added at a maximum concentration of 10% and minimum of 0.04%. It is concluded that the EOs of clove and citronella demonstrate antimicrobial activity against strains of CoPS isolated from canine external otitis. At the concentrations used, melaleuca essential oil did not show any bacteriostatic or bactericidal effects.