Proposed diagnostic criteria for classic cases of Mycoplasma pneumoniae-induced rash and mucositis
| Mucocutaneous eruption | Involvement of ≤10% body surface area |
| Number of mucosal sites involved | ≥2 |
| Few vesiculobullous lesions, or scattered, atypical | Yes |
| Targetoid lesions | ± |
| Clinical evidence of atypical pneumonia | Fever, cough and auscultatory findings |
| Laboratory evidence of atypical pneumonia | Increase in Mycoplasma pneumoniae (MP) IgM antibodies, MP in oropharyngeal or bullae cultures or PCR, and/or serial cold agglutinins |