A boy with ASOM undrgoing treatment with penicillin therapy for 7 days now presents with subsidence of pain and persistence of deafness, diagnosis is -

Inadequate antibiotic treatment of acute suppurative otitis media may inactivate infection but fail to resolve it completely. Low grade infection lingers on which acts as a stimulus for the mucosa to secrete more mucus which leads to development of serous/secretory otitis media.