[Peritonsillar abscess in a child caused by ampicillin resistant Haemophilus influenzae].

An unusual case of peritonsillar abscess in a six year old boy is presented. The abscess was initially treated with penicillin without success and afterwards with ampicillin and tonsillectomy. Cultivation of pus from the abscess revealed beta-lactamase producing Haemophilus influenzae. The patient was finally successfully treated with sulfamethizole.