Unique Presentation of Mycoplasma pneumoniae-Induced Rash and Mucositis with Salivary Gland Inflammation in a Pediatric Patient: A Case Report

Background: Mycoplasma pneumoniae (MP) is a significant respiratory pathogen leading to community-acquired pneumonia (CAP), especially in children. Up to 30% of confirmed MP cases can develop dermatological symptoms, with Mycoplasma pneumoniae-induced rash and mucositis (MIRM) being a distinct clinical entity marked by mucous membrane inflammation, with or without skin lesions. Methods: This case report describes a 7-year-old girl admitted with fever, stomatitis, conjunctivitis, and skin lesions. On the second day, a painful neck enlargement was observed, with ultrasound confirming bilateral submandibular salivary gland inflammation and elevated serum amylase levels. The patient later developed pneumonia, confirmed via chest X-ray and pleural ultrasound. MP infection was confirmed via specific IgM antibodies and PCR in a throat swab. Results: The patient was diagnosed with MIRM and was treated with clarithromycin, amoxicillin with clavulanic acid, and methylprednisolone, resulting in a full recovery. Conclusions: This case highlights a unique presentation of MIRM with salivary gland inflammation, not previously described in pediatric mycoplasmal infections.