Infantile papular acrodermatitis
Synonyms and keywords:  GianottiCrosti syndrome; papular acrodermatitis of childhood; papulovesicular acrolocated syndrome; acrodermatitis papulosa infantum

# Overview
Infantile papular acrodermatitis is a reaction of the skin to a viral infection. Hepatitis B and Epstein-Barr virus are the most frequently reported etiologies. Other incriminated viruses are hepatitis A, hepatitis non A-non B, strep, cytomegalovirus, coxsackie, adenovirus, enterovirus, rotavirus, rubella, HIV and parainfluenza.

# Historical Perspective
It is named for Ferdinando Gianotti and Agostino Crosti.

# Causes
Hepatitis B and Epstein-Barr virus are the most frequently reported etiologies of infantile papular acrodermatitis.
Other incriminated viruses are
- Hepatitis A
- Hepatitis non A-non B
- Cytomegalovirus
- Coxsackie
- Adenovirus
- Enterovirus
- Rotavirus
- Rubella
- HIV
- Parainfluenza.
- Parvovirus B19 infection
- Respiratory syncytial virus

# Differentiating from other Diseases
Infantile papular acrodermatitis must be differentiated from:
- Acrodermatitis enteropathica
- Erythema infectiosum
- Erythema multiforme
- Hand-foot-and-mouth disease
- Henoch-Schonlein purpura
- Kawasaki disease
- Lichen planus
- Papular urticaria
- Papular purpuric gloves and socks syndrome
- Scabies

# Epidemiology and Demographics
Infantile papular acrodermatitis  mainly affects infants and young children.

# Natural History, Complications and Prognosis
- Infantile papular acrodermatitis is a self limiting condition.
- Spontaneous disappearance of the rash usually occurs after 15-60 days.
- Complications occur as a result of associated conditions, rather than as a result of  infantile papular acrodermatitis .

# Diagnosis
The diagnosis of infantile papular acrodermatitis is clinical.  A validated diagnostic criteria is as follows: 
A patient is diagnosed as having infantile papular acrodermatitis if:
- On at least one occasion or clinical encounter, he/she exhibits all the positive clinical features,
- On all occasions or clinical encounters related to the rash, he/she does not exhibit any of the negative clinical features,
- None of the differential diagnoses is considered to be more likely than  infantile papular acrodermatitis on clinical judgment, and
- If lesional biopsy is performed, the histopathological findings are consistent with infantile papular acrodermatitis.
The positive clinical features are:
- Monomorphous, flat-topped, pink-brown papules or papulovesicles 1-10mm in diameter.
- At least three of the following four sites involved  (1) cheeks, (2) buttocks, (3) extensor surfaces of forearms, and (4) extensor surfaces of legs.
- Being symmetrical, and
- Lasting for at least ten days.
The negative clinical features are:
- Extensive truncal lesions, and
- Scaly lesions.

## Symptoms
- Infantile papular acrodermatitis is generally recognized as a papular or papulovesicular skin rash occurring mainly on the face and distal aspects of the four limbs.  The presence of less florid truncal lesions does not exclude the diagnosis.
- Itching
- Asthenia

## Physical Examination

### Skin
- Papular or papulovesicular skin rash occurring mainly on the face and distal aspects of the four limbs.

### Head
- Lymphadenopathy

### Abdomen
- Hepatomegaly

## Gallery
- Acrodermatitis infantile papular.With permission from Dermatology Atlas.
- Acrodermatitis infantile papular.With permission from Dermatology Atlas.
- Acrodermatitis infantile papular.With permission from Dermatology Atlas.
- Acrodermatitis infantile papular.With permission from Dermatology Atlas.
- Acrodermatitis infantile papular.With permission from Dermatology Atlas.
- Acrodermatitis infantile papular.With permission from Dermatology Atlas.
- Acrodermatitis infantile papular.With permission from Dermatology Atlas.
- Acrodermatitis infantile papular.With permission from Dermatology Atlas.

## Laboratory Findings
- Raised liver transmainases with no rise in conjugated and unconjugated bilirubin are sometimes detectable, although the absence of such does not exclude the diagnosis.
- Hepatitis virus serology or hepatitis B surface antigen
- Screening for EBV antibodies
- Serum zinc level may be tested in acrodermatitis enteropathica
- Skin biopsy

# Treatment
Infantile papular acrodermatitis is a harmless and self-limiting condition, so no treatment may be required.  Treatment is mainly focused on controlling itching, symptomatic relief and to avoid any further complications. For symptomatic relief from itching, oral antihistamines or any soothing lotions like calamine lotion or zinc oxide may be used. If there are any associated conditions like streptococcal infections, antibiotics may be required.