Gianotti-Crosti Syndrome

Key Points
Skin condition which initially affects the thighs and buttocks, spreading to other areas
Caused by a reaction to viral infection
Consists of an asymmetrical rash of dull, deep red spots

Gianotti-Crosti Syndrome is a skin condition which initially appears on the thighs and buttocks, and spreads to the arms and face. The condition consists of an asymmetrical rash of dull, deep red spots, which may be accompanied by fever and swollen glands (which may persist). In rare cases, the condition may be accompanied by itching.

Gianotti-Crosti Syndrome is caused by a reaction to viral infection. It is classically associated with hepatitis B infection, but can also occur with Epstein Barr, enterovirus, echovirus, and respiratory synctial virus. The condition usually appears in children under 12.

Differential Diagnosis (Other conditions with similar appearance)
Acute Febrile Neutrophilic Dermatosis
Viral exanthem
Hypersensitivity Vasculitis (Leukocytoclastic Vasculitis)
Impetigo
Behcet Disease
Insect Bites
Churg-Strauss Syndrome (Allergic granulomatosis)

Diagnosis
Key Points
Diagnosis based on the characteristic appearance of the affected area
Blood tests may be performed to check for associated conditions

Gianotti-Crosti Syndrome is typically diagnosed based on the characteristic appearance of the affected area. Blood tests may be performed to check for associated conditions, such as hepatitis B.

Treatment
The condition has no specific treatment, as it is self-resolving
Associated conditions should be treated accordingly
Topical steroids may be prescribed for itching

There is no specific treatment for Gianotti-Crosti Syndrome, as the condition is typically self-resolving (which may take up to 8 weeks). Serious associated conditions, such as hepatitis B, should be treated accordingly. If the condition is accompanied by itching, health care professionals may prescribe topical steroids.