ERYTHEMA MULTIFORME

ETIOLOGY:
  • Idiopathic: Most common cause
  • Viral : HSV (most important) HBV, Mumps, Adenovirus
  • Bacteria :Streptococci, tuberculosis,M. pneumoniae
  • Fungal : Coccidioidomycosis, Histoplasmosis.
  • Drugs -: Antibiotics (Sulphonamide), Phenytoin, NSAIDS.
  • Autoimmune disease: SLE, thyroiditis, RA
  • Others: Sarcoidosis, Pregnancy, Malignancy.
CLASSIFICATION :
  • Erythema multiforme major-typical targets or raised, edematous papules distributed acrally
  • Erythema multiforme minor-typical targets or raised, edematous papules distributed acrally with involvement of one or more mucous membranes; epidermal detachment involves less than 10% of total body surface area (TBSA)
  • Toxic epidermal necrolysis
  • Stevens–Johnson syndrome-widespread blisters predominant on the trunk and face, presenting with erythematous or pruritic macules and one or more mucous membrane erosions; 
  • epidermal detachment is less than 10% TBSA for Stevens-Johnson syndrome and 30% or more for toxic epidermal necrolysis.
CLINICAL FEATURES:
  • Prodromal Features :
  1. Prev Attack (30%) 
  2. Preceding Infection Fever (T>103.1 deg C)
  3. Cutaneous Lesions 
  4. Mucous Lesions 
  • CUTANEOUS LESIONS :
  1. Symmetrical, Acral, Centripetal Rash
  2. Hemorrhagic crusts
  3. Extensor aspect : Extremities > Face > Neck > Trunk
  4. Predilection to Sun-Exposed Areas / Koebnerization 
  5. Well-defined, circular, blanching papule / plaque that persists for 01 week – Self-limiting in 04 weeks – Persistent / Continuous EM 
  • Typical Target Lesion
  1. Dusky Central Disk / Bulla (later Violaceous / Purpuric) 
  2. Infiltrated Pale Ring 
  3. Erythematous edematous halo Larger lesions show Central Bulla and Marginal ring of vesicles , Herpes Iris of Bateman
  4. vesicles, ruptured to form ulcers covered with pseudomembrane
  • Raised Atypical Target lesions / Targetoid lesions
  1. SJS-TEN lesions – mostly Macular MUCOSAL LESIONS 
  2. 70% Cases 
  3. Lips – Cutaneous Target Lesions Serous Crusting
  • MUCOSAL LESIONS :
  1. LIPS – Mucosal (Erosions / Vesicles / Bullae)
  2. GINGIVAL / Ventral Tongue
  3. Hard Palate – Spared 
  4. Pharynx / Larynx / Trachea / Bronchi
  5. Conjunctivitis B/L with Vesicles / Erosions 
  6. Nasal / Urethral / Anal Mucosae 
  7. 2/3 Mucosal Sites sans Cutaneous inv – FUCH’s SYNDROME
  8. Image result for ERYTHEMA MULTIFORME minorImage result for ERYTHEMA MULTIFORME minor


TREATMENT:
  • Treating underlying Etiology 
  • Reducing morbidity – Oral CS
  • Anti-Virals 
  • Macrolides / Quinolones for MPAEM 
  • Oral EM – Topical CS / Anesthetics / Antacids 
  1. RECURRENT EM 
  2. Anti-Virals 
  3. Topical Acyclovir 
  4. Azathioprine 
  5. Thalidomide
Exam Question
  • The most clinically significant skin eruption associated with M. pneumoniae infection is Erythema multiforme major
  • After taking sulphonamide group of drugs, one patient developed certain oral lesions of Erythema multiforme
  • Erythema multiforme lesions consist of vesicles, ruptured to form ulcers covered with pseudomembrane.
  • While touching, the lesions of Erythema multiforme bleed easily with Hemorrhagic crusts on lips and other skin .
  • Commonest etiology among infection of erythema multiforme is Viral
  • In Erythema multiforme Target lesions are seen
  • Erythema multiforme Involves face and neck regions
  • Erythema multiform shows Sign of internal malignancy
  • Erythema multiforme is most commonly caused by idiopathy
Don't Forget to Solve all the previous Year Question asked on ERYTHEMA MULTIFORME