Mycoplasma Pneumoniae-Induced Rash and Mucositis (MIRM) in a Pediatric Patient: A Case Report and Review of Clinical Management

Background: Mycoplasma pneumoniae-induced rash and mucositis (MIRM) is a mucocutaneous eruption occurring primarily in pediatric patients in response to Mycoplasma pneumoniae infection. Although often confused with Stevens-Johnson syndrome (SJS) or erythema multiforme (EM), MIRM is distinguished by specific clinical and serological findings and requires a distinct treatment approach. Case Presentation: A previously healthy 9-year-old child presented with a high fever of 40°C, painful oral ulcers, and atypical target-like lesions on the extremities following a respiratory infection initially diagnosed as pharyngitis. Despite initial antibiotic treatment, mucosal and cutaneous symptoms developed, characterized by mouth ulcers with hemorrhagic crusting and papulo-erythematous lesions on the extremities. A chest X-ray demonstrated mild airway inflammation, and laboratory results showed elevated acute-phase proteins and Mycoplasma pneumoniae IgM and IgG levels. The diagnosis of MIRM was established, and treatment included intravenous steroids, antibiotics (ceftriaxone and azithromycin), and supportive care. The child’s condition improved gradually with complete resolution of symptoms. Conclusion: This case underscores the importance of differentiating MIRM from other mucocutaneous disorders to ensure appropriate diagnosis and treatment in pediatric patients presenting with respiratory symptoms and characteristic mucocutaneous lesions.