Mycoplasma pneumoniae-associated mucositis.

A 9-year-old boy presented to the emergency department of a paediatric hospital with non-painful lesions on his lips and inside his mouth, associated with lip swelling. On examination, his oral mucosa and lips showed numerous blisters with yellowish serofibrinous content and lip oedema. An eye examination revealed bilateral conjunctival injection. Genitalia was unaffected and no other skin lesions were found. He was on day 4 of clarithromycin prescribed for atypical pneumonia caused by Mycoplasma pneumoniae The patient was diagnosed with M. pneumoniae-associated mucositis and was started on topical treatment with fusidic acid and betamethasone, with gradual improvement of the oral lesions.