史帝芬強森症候群(steven johnson syndrome)

Summary

Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are severe, life-threatening conditions where the immune system attacks the skin and mucosal linings. They occur due to type 4 hypersensitivity reactions triggered by certain medications or infections. SJS affects up to 10% of the body, while TEN affects more than 30%. Symptoms include fever, flu-like symptoms, and a painful rash that progresses to blisters and necrosis. Immediate cessation of triggering medications and supportive treatment are critical for managing the conditions. If untreated, both can lead to organ failure, scarring, and even death.

Takeaways

• 😀 Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are acute, potentially fatal immune-mediated conditions affecting the skin and mucous membranes.
• 😀 TEN is a more severe form of SJS, with increased risk of fatality as the severity of the condition rises.
• 😀 The skin serves as a barrier to protect against pathogens and water loss, while mucous membranes line inner body surfaces like the mouth and genitals.
• 😀 Cytotoxic T cells play a key role in SJS and TEN by attacking healthy epithelial cells, leading to cell death and skin/mucosal erosion.
• 😀 These conditions are classified as Type 4 hypersensitivity reactions, with immune cells causing tissue damage through inflammatory cytokines.
• 😀 SJS and TEN differ based on the percentage of body surface area affected: <10% for SJS, 10-30% for overlap, and >30% for TEN.
• 😀 Common triggers for SJS and TEN include specific medications (e.g., anticonvulsants, antibiotics, NSAIDs) and infections (e.g., mycoplasma pneumoniae).
• 😀 Early symptoms of SJS and TEN include flu-like signs such as sore throat, fever, and red eyes, followed by a rash and blistering lesions.
• 😀 Diagnosis is typically clinical but can be confirmed with a biopsy of the affected skin or mucosa.
• 😀 Treatment involves immediate cessation of the triggering medication, supportive care, and sometimes immune modulators (e.g., corticosteroids or IVIG).

Q & A

What are Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN)?

Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN) are severe, immune-mediated conditions that affect the skin and mucous membranes. They are part of the same spectrum of diseases, with TEN being the more severe form. Both conditions can be fatal if not treated promptly.

How do Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis differ?

SJS and TEN differ based on the percentage of the body’s surface area affected. SJS affects less than 10% of the body, while TEN affects more than 30%. If 10-30% of the body is affected, it is considered an overlap between the two conditions.

What triggers the hypersensitivity reactions in Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis?

The hypersensitivity reactions in SJS and TEN are typically triggered by certain medications, such as anticonvulsants, antibiotics, immune modulators, and NSAIDs. Infections like Mycoplasma pneumoniae or Cytomegalovirus can also trigger these conditions.

What is the role of the skin in protecting the body?

The skin plays a vital role in protecting underlying muscles, bones, ligaments, and internal organs by forming a barrier against infectious pathogens and preventing water loss from the body. The outermost layer of the skin, the epidermis, is crucial in maintaining this protective barrier.

How does the immune response lead to the symptoms of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis?

In SJS and TEN, cytotoxic T cells attack and kill the epithelial cells in the mucosa and epidermis. These immune cells release cytotoxins like perforin and granzymes, which cause the affected cells to undergo necrosis and detach from the basement membrane, leading to skin and mucosal erosion and a loss of the protective barrier.

What are some of the distinguishing symptoms of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis?

Distinguishing symptoms of SJS and TEN include fever, flu-like symptoms, a rash with dark red centers, and the development of lesions that can evolve from flat macules to fluid-filled vesicles and large bullae. As necrosis occurs, the skin and mucosal lining may slough off, leaving behind areas resembling severe burns.

What is the Nikolsky sign, and how is it related to Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis?

The Nikolsky sign refers to the detachment of the outer skin layer upon slight rubbing of the lesion. This sign is present in conditions like SJS and TEN, where the skin is compromised and begins to peel due to the immune response.

How is a clinical diagnosis of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis made?

A clinical diagnosis of SJS and TEN is typically made based on the presentation of symptoms. However, a biopsy of the affected skin or mucosa can help confirm the diagnosis.

What is the typical treatment approach for Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis?

Treatment typically involves hospitalization, often in a burn or intensive care unit for severe cases. The first step is to stop the triggering medication. Treatment may also include systemic immune modulators like antihistamines, intravenous immunoglobulin (IVIG), or corticosteroids to suppress the immune response. Supportive care, including pain management, hydration, and wound care, is crucial to prevent further complications.

What are the potential long-term effects of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis?

After healing, patients with SJS or TEN may experience scarring. Additionally, complications like infection, dehydration, and organ dysfunction can occur due to the loss of the skin barrier.