Atypical Stevens-Johnson Syndrome Associated With Mycoplasma Pneumoniae.

Mycoplasma pneumoniae primarily causes atypical pneumonia in children and young adults. 7%-8% of patients with M. pneumoniae infections may experience extra-pulmonary manifestations, including M. pneumoniae-associated Stevens-Johnson Syndrome (SJS), also known as atypical SJS. In recent literature, there have been a few reports of isolated mucositis in children with M. pneumoniae infections. Due to significant overlap with several diseases, including autoimmune disease and infections, atypical mucositis associated with M. pneumoniae is often a diagnostic challenge. In addition, due to limited cases of M. pneumoniae-associated SJS, there is no established standardized treatment guideline that has been shown to reduce hospitalization duration and/or disease progression associated with M. pneumoniae-associated SJS. We report a case of isolated mucositis in the absence of cutaneous involvement in a 10-year-old patient with an acute M. pneumoniae infection. Examination revealed erythematous ulcerations of his lips and pharynx with patchy exudates and bilateral submandibular lymphadenopathy. Laboratory investigation revealed a negative respiratory polymerase chain reaction (PCR) panel, which included M. pneumoniae. Further testing revealed a positive M. pneumoniae immunoglobulin M (IgM) titer on enzyme immunoassay. The diagnosis of atypical SJS was made secondary to M. pneumoniae. Treatment was initiated with systemic steroids and oral antibiotics. Limitations in diagnostic testing for M. pneumoniae in combination with non-specific clinical presentation make for challenges in confirming this pattern of SJS due to a primary M. pneumoniae infection. In this case, serological testing confirmed our suspected diagnosis, which guided treatment and helped reveal some of the difficulties in diagnosing and managing M. pneumoniae-associated SJS.