Severe erythema multiforme (Stevens-Johnson syndrome)

Overview Of Severe erythema multiforme (Stevens-Johnson syndrome)

Severe erythema multiforme (EM), also known as Stevens-Johnson syndrome (SJS), is a rare but life-threatening hypersensitivity reaction affecting the skin and mucous membranes. It is characterized by widespread erythematous macules, target lesions, and blistering, often accompanied by mucosal involvement in the eyes, mouth, and genital areas. SJS is considered a severe form of erythema multiforme and is often triggered by medications or infections. The condition is a medical emergency due to its potential for rapid progression, systemic complications, and high mortality rate. SJS overlaps with toxic epidermal necrolysis (TEN), a more severe condition with greater skin detachment. Early recognition and intervention are critical to improving outcomes.

Causes of Severe erythema multiforme (Stevens-Johnson syndrome)

• The primary causes of SJS include adverse drug reactions and infections. Medications are the most common triggers, with antibiotics (e.g., sulfonamides, penicillins), anticonvulsants (e.g., phenytoin, carbamazepine), and nonsteroidal anti-inflammatory drugs (NSAIDs) being frequent culprits. Infections, particularly Mycoplasma pneumoniae and herpes simplex virus (HSV), are also significant triggers. Genetic factors, such as specific human leukocyte antigen (HLA) alleles, may predispose individuals to SJS. The condition results from a complex immune-mediated response, leading to keratinocyte apoptosis and widespread epidermal detachment. Discontinuing the offending agent is crucial to halting disease progression.

Risk Factors of Severe erythema multiforme (Stevens-Johnson syndrome)

• Several factors increase the risk of developing SJS:
• Medication Use: Certain drugs, particularly sulfonamides, anticonvulsants, and NSAIDs, are strongly associated with SJS.
• Infections: Mycoplasma pneumoniae and HSV infections are common triggers.
• Genetic Predisposition: HLA alleles, such as HLA-B*15:02 and HLA-A*31:01, are linked to increased susceptibility.
• Immunocompromised State: Patients with HIV or other immunodeficiencies are at higher risk.
• Previous History: A history of SJS or TEN increases the likelihood of recurrence.
• Age and Gender: SJS is more common in children and young adults, with a slight female predominance.

Prevention of Severe erythema multiforme (Stevens-Johnson syndrome)

• Preventing SJS involves avoiding known triggers and implementing safety measures:
• Medication Safety: Patients with a history of SJS should avoid high-risk medications.
• Genetic Testing: Screening for HLA alleles associated with SJS before prescribing certain drugs can reduce risk.
• Infection Control: Prompt treatment of infections, particularly Mycoplasma pneumoniae and HSV, may prevent SJS.
• Patient Education: Informing patients about the signs and symptoms of SJS enables early recognition and intervention.
• Drug Monitoring: Close monitoring of patients on high-risk medications can help detect early signs of hypersensitivity.

Prognosis of Severe erythema multiforme (Stevens-Johnson syndrome)

• The prognosis of SJS depends on the extent of skin involvement, the presence of systemic complications, and the timeliness of intervention. Mortality rates range from 5% to 15%, with higher rates in older adults and those with extensive skin detachment. Early withdrawal of the causative agent and aggressive supportive care improve survival. Long-term sequelae may include scarring, pigmentation changes, and ocular complications such as chronic dry eye or blindness. Psychological support is often needed due to the traumatic nature of the disease and its impact on quality of life.

Complications of Severe erythema multiforme (Stevens-Johnson syndrome)

• SJS can lead to severe complications, including:
• Sepsis: Secondary bacterial infections of denuded skin can lead to septicemia.
• Ocular Damage: Corneal ulceration, scarring, and blindness may occur.
• Respiratory Failure: Mucosal involvement in the airways can cause acute respiratory distress.
• Renal Failure: Acute tubular necrosis may result from dehydration or drug toxicity.
• Gastrointestinal Involvement: Esophageal strictures or perforation can occur.
• Psychological Impact: The disfiguring nature of the disease can lead to depression or anxiety.

Related Diseases of Severe erythema multiforme (Stevens-Johnson syndrome)

• SJS shares similarities with several other conditions, including:
• Toxic Epidermal Necrolysis (TEN): A more severe form of SJS with greater skin detachment (>30% of body surface area).
• Erythema Multiforme Major: A less severe form of EM with mucosal involvement but less systemic toxicity.
• Drug Reaction with Eosinophilia and Systemic Symptoms (DRESS): A hypersensitivity reaction characterized by rash, fever, and multi-organ involvement.
• Staphylococcal Scalded Skin Syndrome (SSSS): A condition caused by exfoliative toxins from Staphylococcus aureus, presenting with widespread skin peeling.
• Pemphigus Vulgaris: An autoimmune blistering disorder that can mimic SJS but has distinct histopathological features. Understanding these related diseases aids in differential diagnosis and management.

Treatment of Severe erythema multiforme (Stevens-Johnson syndrome)

The treatment of SJS requires immediate discontinuation of the offending agent and supportive care in a specialized burn or intensive care unit. Fluid and electrolyte management is critical to prevent dehydration and renal failure. Wound care involves the use of non-adhesive dressings and topical antibiotics to prevent secondary infections. Pain management with opioids and mucosal care with saline rinses or artificial tears are essential. Systemic corticosteroids are controversial but may be used in early stages. Intravenous immunoglobulin (IVIG) or cyclosporine may be considered to modulate the immune response. In severe cases, plasmapheresis or biologic therapies like anti-TNF agents may be employed. Multidisciplinary care is crucial for optimal outcomes.