Mycoplasma pneumoniae-Associated Reactive Infectious Mucocutaneous Eruption Mimicking Atypical Stevens-Johnson...

Reactive infectious mucocutaneous eruption (RIME) is an infection-associated mucositis syndrome previously described under terms including incomplete Stevens-Johnson syndrome (SJS), Fuchs syndrome, and Mycoplasma pneumoniae-induced rash and mucositis (MIRM). It is characterised by an infectious prodrome, prominent mucosal involvement, and sparse or absent cutaneous disease. Severe ocular involvement may clinically mimic atypical Stevens-Johnson syndrome. We report the case of a previously healthy woman in her 20s who developed coryzal symptoms and self-treated with ibuprofen, paracetamol, and pseudoephedrine before presenting with worsening cough, pyrexia, odynophagia, and bilateral conjunctival discharge. She received doxycycline and topical chloramphenicol but re-presented overnight with rapidly progressive lip swelling, dysphagia, oral mucosal ulceration, and severe bilateral ocular inflammation without cutaneous lesions. Recent exposure to non-steroidal anti-inflammatory medication and doxycycline created initial diagnostic uncertainty, while the preceding respiratory prodrome and skin-sparing mucositis supported infection-associated RIME. Ophthalmological assessment demonstrated severe ocular surface inflammation with pseudomembrane formation, early symblepharon, and progressive corneal involvement, requiring tertiary transfer and amniotic membrane grafting. Initial chest radiography and respiratory multiplex polymerase chain reaction (PCR) testing were negative, including for Mycoplasma pneumoniae; however, subsequent serology returned positive for Mycoplasma pneumoniae IgM. Later drug challenge testing demonstrated tolerance to suspected medications, supporting an infection-associated rather than drug-induced aetiology. This case highlights that Mycoplasma pneumoniae-associated RIME may mimic atypical Stevens-Johnson syndrome, particularly when severe ocular and oral mucositis occurs after recent medication exposure. Early dermatology and ophthalmology involvement, combined molecular and serological testing, and prompt ocular treatment are essential to reduce long-term ocular morbidity.