SSSS, TEN, SJS Differences PDF

# Difference between SSSS, TEN, SJS The key differences between Staphylococcal Scalded Skin Syndrome (SSSS), Toxic Epidermal Necrolysis (TEN), and Stevens-Johnson Syndrome (SJS) are summarized below based on their etiology, pathophysiology, clinical features, and treatment: ## 1. Staphylococcal Sc...

# Difference between SSSS, TEN, SJS The key differences between Staphylococcal Scalded Skin Syndrome (SSSS), Toxic Epidermal Necrolysis (TEN), and Stevens-Johnson Syndrome (SJS) are summarized below based on their etiology, pathophysiology, clinical features, and treatment: ## 1. Staphylococcal Scalded Skin Syndrome(SSSS) - **Etiology:** Caused by exotoxins (exfoliative toxins A and B) produced by *Staphylococcus aureus*. - **Age group:** Primarily affects neonates and young children (rare in adults). - **Pathophysiology:** Exfoliative toxins target *desmoglein-1*, leading to cleavage within the epidermis (stratum granulosum). ### Clinical Features: - Fever, irritability, and skin tenderness. - Widespread erythema followed by superficial flaccid blisters and large sheets of epidermal peeling. - Nikolsky sign positive (epidermis detaches with gentle pressure). - No mucosal involvement. - **Histopathology:** Cleavage occurs at the granular layer of the epidermis. ### Treatment: - Antistaphylococcal antibiotics (e.g., oxacillin, clindamycin). - Supportive care (hydration, wound care). ## 2. Stevens-Johnson Syndrome (SJS) - **Etiology:** Severe immune-mediated hypersensitivity reaction, often triggered by drugs (e.g., sulfonamides, anticonvulsants) or infections (e.g., *Mycoplasma pneumoniae*). - **Age group:** All ages, including children. - **Pathophysiology:** Cytotoxic T cells induce keratinocyte apoptosis via Fas-Fas ligand interaction. ### Clinical Features: - Flu-like prodrome (fever, sore throat). - Erythematous macules progressing to targetoid lesions and epidermal detachment (less than 10% of body surface area (BSA)). - Prominent mucosal involvement (oral, ocular, genital). - Nikolsky sign positive. - **Histopathology:** Full-thickness epidermal necrosis. ### Treatment: - Stop the offending agent immediately - Supportive care in ICU or burn unit - Consider immunomodulation (e.g., IVIG, corticosteroids) in select cases. ## 3. Toxic Epidermal Necrolysis (TEN) - **Etiology:** Similar to SJS (drug-induced hypersensitivity). - **Age group:** All ages but more severe in adults. - **Pathophysiology:** Extensive keratinocyte apoptosis due to cytotoxic T-cell activity. ### Clinical Features: - Similar to SJS but involves greater than 30% of BSA. - Severe skin and mucosal involvement with widespread sloughing of epidermis. - Nikolsky sign positive. - Systemic complications (e.g., dehydration, infection, multiorgan failure). - **Histopathology:** Full-thickness epidermal necrosis with subepidermal detachment. ### Treatment: - Stop the causative drug. - Aggressive supportive care (fluid replacement, wound care, temperature control). - Use of IVIG or immunosuppressive therapy (controversial). ## Key Differences Summary Table: | Feature | SSSS | SJS | TEN | |--------------|--------------------------------------|---------------------------------------|---------------------------------------| | Etiology | *S. aureus* exotoxin | Drugs, infections | Drugs, infections | | Age Group | Neonates, young children | All ages | All ages | | Skin Involvement | Superficial (epidermis only) | Epidermal necrosis (<10% BSA) | Epidermal necrosis (>30% BSA) | | Mucosal Involvement | Absent | Present | Present | | Nikolsky Sign | Positive | Positive | Positive | | Histology | Granular layer cleavage | Full-thickness necrosis | Full-thickness necrosis | | Treatment | Antibiotics, supportive care | Stop drug, supportive care | Stop drug, supportive care | Let me know if you need further clarification! ## Then what is Erythema Multiforme # Erythema Multiforme (EM) Erythema multiforme (EM) is an immune-mediated hypersensitivity reaction involving the skin and mucous membranes. It is a distinct condition from Stevens-Johnson Syndrome (SJS) and Toxic Epidermal Necrolysis (TEN), although there can be some overlap in clinical presentation. EM is generally less severe and has different etiological and clinical characteristics. ## Key Features of Erythema Multiforme ### 1. Etiology: - Most commonly triggered by infections (especially Herpes simplex virus (HSV)). - Less frequently associated with drugs (e.g., sulfonamides, NSAIDs, anticonvulsants). - Other triggers: *Mycoplasma pneumoniae*, vaccinations, or malignancies. ### 2. Pathophysiology: - **Type IV hypersensitivity reaction:** Immune response leads to deposition of immune complexes in small dermal blood vessels and subsequent inflammation. ### 3. Clinical Features: #### Skin Lesions: - **Target lesions:** Pathognomonic feature of EM. - Three distinct zones: a central dusky or blistered area, a pale edematous ring, and an erythematous halo. - Often symmetrical, involving palms, soles, extensor surfaces, and mucocutaneous junctions. - Lesions may coalesce but usually remain discrete. #### Mucosal Involvement: - Seen in Erythema Multiforme Major but is typically mild compared to SJS. - Oral ulcers, conjunctivitis, and genital erosions may occur. #### Systemic Symptoms: - Absent or mild (fever, malaise in some cases). ### 4. Classification: - **Erythema Multiforme Minor:** - Limited to the skin, with target lesions. - No or minimal mucosal involvement. - **Erythema Multiforme Major:** - Mucosal involvement is present (usually oral mucosa, less commonly ocular or genital). - More widespread but not life-threatening. ### 5. Differences from SJS/TEN: | Feature | Erythema Multiforme | SJS / TEN | |--------------|---------------------------|---------------------------------| | Trigger | Infections (e.g., HSV) | Drugs, infections | | Lesion Type | Target lesions | Macules progressing to bullae | | Mucosal Involvement | Absent (minor) / mild | Prominent, severe | | Nikolsky Sign | Negative | Positive | | Severity | Self-limiting | Severe, potentially fatal | ### 6. Treatment: #### General Management: - Identify and treat the underlying cause (e.g., antivirals for HSV). - Supportive care: hydration, analgesics, topical steroids for symptomatic relief. #### Erythema Multiforme Major: - May require systemic corticosteroids or hospitalization if mucosal involvement is significant. #### Recurrent EM: - Consider prophylactic antiviral therapy if HSV is a recurrent trigger. Erythema multiforme is generally self-limiting and has a **good prognosis**, unlike SJS/TEN, which are associated with significant morbidity and mortality. Let me know if you'd like further clarification!