RESUMEN
In this study, 130 children with acute otitis media were examined and subjected to myringotomy and aspiration of middle ear fluid. Only 50 patients could attend accurately at the follow up. Middle ear aspirates were cultured. Sera were collected from patients at days 0, 7 and 14 examined by indirect immunofluorescent technique for specific 1gG and 1gM against the causative organism. After myringotomy, patients were divided into two groups. Group A, received Velosef 75 mg /kg/day orally in 4 divided doses for 1 w. Group B, received the same antibiotic, but starting 3 days after myringotomy. Follow up by tympanometry and audiometry was done after 2 weeks and 1 month. Discharge rapidly stopped in group A [mean 2.24 d.], while in group B stopped 3 days after [mean 3.24 d.]. Effusion persisted in 5 cases of group A and 3 cases of group B. Only 1 case of group A showed rising titer of Ig, while 3 cases of group B did so. So late administration of cephradine is accompanied by more active immune response and more rapid resolution of middle ear effusion