Swab and aspiration specimen collection methods and antibiogram in chronic suppurative otitis media at Jos University Teaching Hospital: Which is superior?

BACKGROUND Chronic suppurative otitis media is a very common otologic problem in our environment. Appropriate methods for obtaining sample specimens for specific bacteria isolation has generated a lot of controversy. The simplest method available in our environment is the traditional swab method which, however, has been condemned on the basis of introducing contaminants. The objectives of this study were to compare the bacterial yield and the antibiogram of two specimen collection methods: the traditional swab method and aspiration method. METHOD This was a 3-month prospective study involving outpatients seen at both the emergency and outpatients' clinics of the Jos University Teaching Hospital in the period between May 2008 and July 2008. The biodata, duration of discharge and sites of samples were recorded in the study data form after obtaining consent from the patients or the parents of child. RESULTS Eighty patients were studied comprising 40 each for aspiration and swab technique. This consists of 30 males (37.5%) and 50 females (62.5%) with a male to female ratio of 1:1.7. There were 24 (30%) children (14 males, 10 females). Six (4 males, 2 females) and 74 (26 males, 48 females) patients had bilateral and unilateral ear discharges, respectively. A total of 86 specimens were obtained in all, consisting of 42 left and 44 right ears. There were 68 bacteria isolates comprising Pseudomonas (30), Staphylococcus (18), Proteus (12), and (8) Klebsiella species. Two were incidental fungal isolates of (Candida species), (8) cultures grew contaminants and (10) specimens had no growth at all. Each of the swab and aspiration techniques had (44) specimens. CONCLUSIONS Despite the controversy surrounding the sampling technique in literature, swab technique has been found to be as good as the aspiration technique in our study. The organisms isolated are the same as those obtained in other places. Contaminants found were few and occurred in equal amount in the same patients in the two methods.