Erythema By Dr. Mohamad Nasr Lecturer Of Dermatology & Venereology Erythema Erythema is a skin condition characterized by redness or rash. Types 1. 2. 3. Photosensitivity Erythema multiforme Erythema nodusum. Photosensitivity Photosensitivity is caused by a reaction to sunlight and tends to occur when something, such as an infection or a medication, increases your sensitivity to ultraviolet radiation. Erythema multiforme Erythema multiforme is an acute or subacute selflimiting disease that involves the skin and mucous membranes. The etiology is unclear. However, an immunologically mediated process triggered by herpes simplex or Mycoplasma pneumoniae, drugs, radiation or malignancies, is probable. Age: the ages of 20 and 30 years Sex: The disease more frequently affects young men. Clinical Features Fatigue, fever, itching (before lesions appear) The skin manifestations consist of erythematous, flat, round macules, papules, or plaques, usually in a symmetrical pattern. -The characteristic skin patterns are target- or iris-like lesions. Skin bullae may occasionally be seen. Stevens-Johnson syndrome (SJS) & toxic epidermal necrolysis (TEN) The most severe forms of erythema multiforme. The oral lesions are always present, and are characterized by extensive vesicle formation, followed by painful erosions covered by grayish-white or hemorrhagic pseudomembranes. Drugs usually trigger the disease Age: young adults Sex: Male predilection A person with TEN will have symptoms of SJS that worsen to include peeling and detachment of the skin, pus-like infections, fluid loss and even death. Stevens-Johnson syndrome Toxic Epidermal Necrolysis Treatment 1. Prevention; Treat any underlying diseases and avoid any known triggers (certain medications, for example). 2. Drug Therapies; Antihistamines for itching Antibiotics, if you have an infection Antiviral medications such as acyclovir and valacyclovir, if you have a virus Corticosteroids -- applied to the skin (topically); corticosteroids may also be taken orally. Treatment of TEN & SJS; Management should be in an intensive care unit: Supportive care (warm environment, fluid replacement, correction of electrolyte disturbances, prevention of sepsis, suction of oropharynx) Analgesics Intravenous antibiotics for sepsis Debridement of frankly necrotic skin Non-stick occlusive burns dressings Granulocyte colony stimulating factor for neutropaenia Intravenous immunoglobulins or ciclosporin to arrest the cytotoxic process Erythema nodosum (EN) EN is an acute, nodular, erythematous eruption that usually is limited to the extensor aspects of the lower legs. EN is a hypersensitivity reaction that may occur in association with several systemic diseases or drug therapies, or it may be idiopathic. Age: peak 20 - 30 years of age Sex: Female predilection Etiology 1. 2. 3. 4. 5. Streptococcal infections are the most frequent Drugs Sarcoidosis Autoimmune disorders Inflammatory diseases of the bowel Clinical features EN begins with flulike symptoms of fever and generalized aching. Lesions begin as red tender nodules . Lesion borders are poorly defined and vary from 2-6 cm. During the first week, lesions become tense, hard and painful. During the second week, they may become fluctuant, as in an abscess, but do not suppurate or ulcerate. Individual lesions last approximately 2 weeks, but occasionally, new lesions continue to appear for 3-6 weeks. Treatment In most patients, EN is a self-limited disease and requires only symptomatic relief using NSAIDs (eg, indomethacin) , cool wet compresses, elevation and bed rest. Corticosteroids are effective but seldom necessary in self-limited disease.