Dermatitis herpetiformis: Difference between revisions
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==Background== | ==Background== | ||
{{Skin anatomy background images}} | {{Skin anatomy background images}} | ||
*Autoimmune disorder associated gluten sensitivity | *Autoimmune blistering skin disorder strongly associated with celiac disease (gluten sensitivity) | ||
*IgA deposits at dermal papillae cause neutrophilic inflammation | |||
*Nearly all patients (>90%) have underlying celiac disease on intestinal biopsy, though most are asymptomatic from GI perspective | |||
*Peak age: 30-40 years; male predominance | |||
{{Dermatitis types}} | {{Dermatitis types}} | ||
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==Clinical Features== | ==Clinical Features== | ||
[[File:Dermatitis-herpetiformis2.jpg|thumbnail|Characteristic rash]] | [[File:Dermatitis-herpetiformis2.jpg|thumbnail|Characteristic rash]] | ||
* | *Intensely pruritic papulovesicular eruption in '''symmetric''' distribution | ||
*Characteristic locations: elbows, knees, shoulders, buttocks, sacrum, scalp | |||
*Grouped vesicles on erythematous base (herpetiform pattern — hence the name, though unrelated to [[herpes]]) | |||
*Excoriations often predominate (patients scratch off the vesicles) | |||
*Resembles [[scabies]] but distribution is more extensor surfaces | |||
==Differential Diagnosis== | ==Differential Diagnosis== | ||
*[[Scabies]] | *[[Scabies]] | ||
*[[Linear IgA bullous dermatosis]] | |||
*[[Herpes simplex virus|HSV]] | |||
*[[Contact dermatitis]] | |||
{{Bullous rashes DDX}} | {{Bullous rashes DDX}} | ||
==Evaluation== | ==Evaluation== | ||
*Skin biopsy with direct immunofluorescence (gold standard): granular IgA deposits at dermal papillae | |||
*Tissue transglutaminase (tTG) IgA — elevated in most patients | |||
*Consider referral for intestinal biopsy to confirm celiac disease | |||
==Management== | ==Management== | ||
*Gluten-free diet | *'''Gluten-free diet''' — mainstay of long-term treatment (improves skin and GI disease) | ||
*[[Dapsone]] | *'''[[Dapsone]]''' — rapid relief of symptoms (often within 24-48 hours) | ||
*{{AntibioticDose|drug=Dapsone|dose=50mg PO QD|context=Dermatitis herpetiformis|disease=Dermatitis herpetiformis|population=Adult}} | *{{AntibioticDose|drug=Dapsone|dose=50mg PO QD|context=Dermatitis herpetiformis|disease=Dermatitis herpetiformis|population=Adult}} | ||
*Check G6PD level before starting dapsone (risk of hemolytic anemia) | |||
*Monitor CBC regularly on dapsone therapy | |||
==Disposition== | ==Disposition== | ||
*Discharge with dermatology referral | |||
*Consider GI referral for celiac disease evaluation | |||
==See Also== | ==See Also== | ||
*[[Rash]] | *[[Rash]] | ||
*[[Celiac disease]] | |||
*[[Bullous pemphigoid]] | |||
==References== | |||
<references/> | |||
[[Category:Dermatology]] | [[Category:Dermatology]] | ||
Latest revision as of 01:26, 21 March 2026
Background
- Autoimmune blistering skin disorder strongly associated with celiac disease (gluten sensitivity)
- IgA deposits at dermal papillae cause neutrophilic inflammation
- Nearly all patients (>90%) have underlying celiac disease on intestinal biopsy, though most are asymptomatic from GI perspective
- Peak age: 30-40 years; male predominance
Dermatitis Types
- Atopic dermatitis
- Candida dermatitis
- Cercarial dermatitis
- Contact dermatitis
- Dermatitis herpetiformis
- Diaper dermatitis
- Dyshidrotic dermatitis
- Neonatal seborrhoeic dermatitis
- Nummular dermatitis
- Perianal streptococcal dermatitis
- Perioral dermatitis
- Seborrheic dermatitis
- Stasis dermatitis
Clinical Features
- Intensely pruritic papulovesicular eruption in symmetric distribution
- Characteristic locations: elbows, knees, shoulders, buttocks, sacrum, scalp
- Grouped vesicles on erythematous base (herpetiform pattern — hence the name, though unrelated to herpes)
- Excoriations often predominate (patients scratch off the vesicles)
- Resembles scabies but distribution is more extensor surfaces
Differential Diagnosis
Vesiculobullous rashes
Febrile
- Diffuse distribution
- Varicella (chickenpox)
- Smallpox
- Monkeypox
- Disseminated gonococcal disease
- DIC
- Purpural fulminans
- Localized distribution
Afebrile
- Diffuse distribution
- Bullous pemphigoid
- Drug-Induced bullous disorders
- Pemphigus vulgaris
- Phytophotodermatitis
- Erythema multiforme major
- Bullous impetigo
- Localized distribution
- Contact dermatitis
- Herpes zoster (shingles)
- Dyshidrotic eczema
- Burn
- Dermatitis herpetiformis
- Erythema multiforme minor
- Poison Oak, Ivy, Sumac dermatitis
- Bullosis diabeticorum
- Bullous impetigo
- Folliculitis
Evaluation
- Skin biopsy with direct immunofluorescence (gold standard): granular IgA deposits at dermal papillae
- Tissue transglutaminase (tTG) IgA — elevated in most patients
- Consider referral for intestinal biopsy to confirm celiac disease
Management
- Gluten-free diet — mainstay of long-term treatment (improves skin and GI disease)
- Dapsone — rapid relief of symptoms (often within 24-48 hours)
- Dapsone 50mg PO QD
- Check G6PD level before starting dapsone (risk of hemolytic anemia)
- Monitor CBC regularly on dapsone therapy
Disposition
- Discharge with dermatology referral
- Consider GI referral for celiac disease evaluation