8-year-old diagnosed with mycoplasma-induced rash and mucositis
An 8-year-old girl was taken to the dermatology clinic after complaining of painful lip crusting, mouth ulcers, rash, and vaginal soreness for three days. A fever and cough had begun ten days before the presentation. She has no prior medical history. Physical examination revealed conjunctivitis in both eyes and oropharyngeal ulcers. Her face was covered in vesicular lesions, and her swollen, bleeding, exudative lips made opening her mouth difficult (Panel A). Targetoid lesions with vesicles were detected all over her arms and legs (Panel B, left leg), as well as several tiny ulcers in the vulvar and perianal regions. The patient was diagnosed with a mycoplasma-induced rash.
Rales may be heard in both lung bases. Chest imaging revealed infiltrates in both lungs. Mycoplasma pneumoniae was detected in serum IgM antibody tests and sputum polymerase chain reaction tests. Mycoplasma-induced rash and mucositis were diagnosed. Although this postinfection mucocutaneous condition has symptoms comparable to Stevens-Johnson syndrome, the prognosis is better. Supportive care was provided, and the pneumonia was treated with doxycycline. The mucocutaneous lesions had resolved two weeks after presentation, and the pneumonia symptoms had resolved shortly after.
Mycoplasma pneumonia is a common infection that may cause community-acquired pneumonia
Mycoplasma pneumoniae (MP) is a common infection that can cause community-acquired pneumonia (CAP).1 According to one 2016 meta-analysis, MP accounts for 10.1% of all CAP, with greater rates in children (17.6%) compared to adults (7.2%).1 Extrapulmonary manifestations of MP affect approximately 25% of patients, and include pericarditis (inflammation of the pericardium), thrombosis (blood clot), hepatitis (inflammation of the liver), hemolytic anaemia (inflammation of red blood cells), arthritis (inflammation of joints), encephalitis (inflammation of the brain), glomerulonephritis (inflammation of the kidneys), mucositis (inflammation of the mucosa) and other dermatologic manifestations.
Historically, Mycoplasma pneumoniae dermatologic signs were thought to be in the range of erythema multiforme (EM), Steven-Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN).3 EM is a skin immunological reaction that manifests as raised red rashes of various forms, as opposed to SJS, which is characterised by a painful rash that blisters and sheds skin over the body and mucous membranes. Toxic epidermal necrolysis is a more severe variant of SJS that affects a larger portion of the body’s surface.3 A smaller retrospective study of 30 paediatric patients examined for probable causes of EM and discovered that more than 13.3% tested positive for MP.
Studies suggest that the disease is a distinct process on its own
Although MP-related mucocutaneous disease has previously been classified as a subset of EM, SJS, and TEN, recent research suggests that it is a distinct disease process in its own right. Canavan and colleagues published the broadest systematic study to date in 2014, and they were the first to define Mycoplasma-induced rash and mucositis (MIRM) as a distinct disease condition.2 This was based on an examination of 202 cases of mucocutaneous (mucous membrane and skin) illness in Mycoplasma pneumoniae-positive patients.
Canavan et al observed varied degrees of mucosal involvement with or without cutaneous involvement in their clinical studies. They discovered a novel illness morphology that did not fit into the accepted diagnosis of EM, SJS, and TEN. MIRM features prominent mucositis (mucosal inflammation) with or without the typical skin vesicles and/or atypical target-shaped eruption seen in the SJS spectrum. MIRM also has a milder clinical course, fewer sequelae, and reduced mortality when compared to EM, SJS, and TEN. Other research has found that the pathophysiology and therapy of this separate clinical entity differ from those of previously identified Mycoplasma-induced erythema multiforme.
M. pneumoniae infection with concomitant mucocutaneous involvement is rare, but more common in children and men. Antibiotic therapy for M. pneumoniae pneumonia should be commenced, while mucocutaneous lesions should be treated primarily supportively. Targeted skin lesions in the context of community-acquired pneumonia, along with mucosal ulcerations and ocular involvement, should highlight the possibility of Mycoplasma pneumoniae-induced rash and mucositis.