Erythema Multiforme - Symptomen, Oorzaken en Behandelingen van deze Huidziekte

Introduction

Erythema multiforme (EM) is a cutaneous and mucosal hypersensitivity reaction with characteristic lesions triggered by certain antigenic stimuli. It represents an acute, sometimes recurrent condition of the skin and mucosal membranes manifested by papular, bullous, and necrotic lesions. Its causes are variable and numerous, and its evolution is generally favorable.[1][2][3][4]

Most lesions appear in 48 to 72 hours and favor the extremities. The lesions remain localized to one site and heal within 7 to 21 days. Common precipitating factors include herpes simplex virus, histoplasmosis, and Epstein Barr virus. Recurrences are not uncommon if the trigger is Herpes simplex. While most cases are mild, severe cases can be life-threatening. The mucous membranes are involved in 2 to 10% of individuals. Overall, the majority of cases of EM are linked to medications.

Wat zijn de verschijnselen?

Erythema multiforme kan op elke leeftijd optreden. In 80% van de gevallen is de aandoening niet ernstig en voelt men zich niet ziek. De huidafwijkingen worden vooral gezien op de handen (zowel de handruggen als de handpalmen), de polsen, de voeten, de ellebogen en de knieën. De huiduitslag van erythema multiforme kan bestaan uit vlekken, bobbeltjes, galbulten, zogenoemde ‘schietschijven’ of een combinatie daarvan. Deze huidafwijkingen zijn rood van kleur, kunnen klein blijven maar ook wel 3 centimeter groot worden.

Soms zijn er maar enkele huidafwijkingen, soms is de uitslag zeer uitgebreid. In het laatstgenoemde geval is er sprake van een ernstiger aandoening het Stevens-Johnson syndroom, waarbij de patiënt ook ziek kan zijn. Daarnaast doen dan ook de slijmvliezen mee, meestal van de mond en soms andere slijmvliezen (geslachtsorganen, ogen).

Who gets erythema multiforme?

Erythema multiforme affects less than 1% of the population. It is most common in young adults (aged 20–40 years) with a modest predominance in males. There is no association with race.

Mycoplasma pneumoniae infection is often listed as a trigger of erythema multiforme, however mucocutaneous rash and mucositis (MIRM).

Medications which may trigger erythema multiforme include:

• Antibiotics (including erythromycin, nitrofurantoin, penicillins, sulfonamides, and tetracyclines)
• Anti-epileptics
• Non-steroidal anti- Lymphoma
• DNA is then transferred to the keratinocytes. Within the keratinocyte layer, expression of viral DNA fragments induces a cell-mediated immune response, including the production of interferon-γ which upregulates the inflammatory process.

Pathophysiology

EM is often associated with viral or bacterial infections, especially HSV. Studies have demonstrated the presence of HSV-DNA by a polymerase chain reaction in acute or sequellae EM lesions. The predisposing factors are unknown. HLA-DQ3 is reported to be associated with postherpetic EM and has been suggested as an additional diagnostic marker. Other human leukocyte antigen groups have also been reported as markers of recurrent EM.

The damage to the epithelial cells is via cell-mediated immunity. During the early phase of the disease, there is an influx of macrophages and CD8 T lymphocytes, which release a wide range of cytokines that mediate the inflammation and resultant cell death.

When the process is due to drug hypersensitivity, the earliest pathological feature is necrosis of keratinocytes.