Gianotti Crosti syndrome (GCS), also known as Papular acrodermatitis of childhood, acrodermatitis papulosa infantum, and infantile papular acrodermatitis, is a symmetric papular eruption of the skin in response to viral or bacterial infection. This condition is harmless and self-limiting which usually resolves in about 3-5 weeks.

Gianotti-Crosti syndrome usually occurs in children between the ages of 3 months to 15 years and is more commonly seen in children younger then 4 years. In children, both male and female are equally affected. However, in adult population it tends to occur more in females then male.

What causes Gianotti Crosti syndrome?
Although previous studies have associated with viral infection specifically hepatitis B virus, recent advance in research have associated its involvement with several viral and bacterial infection.

Causes associated with viral infection:
Epstein-Barr virus
Hepatitis A, B and C
Cytomegalovirus
Coxsackievirus
Rotavirus
Parainfluenza virus
Human herpesvirus 6
Rubella virus
Adenovirus
Echovirus
Molluscum contagiosum virus
Enterovirus
Human immunodeficiency virus
Respiratory syscytial virus

Causes associated with bacterial infections:
Meningococcemia
Mycoplasma pneumoniae
Group A b-hemolytic streptococci
Borrelia burgdorferi
Mycobacterium avium-intracellulare
Bartonella henselae

Causes associated with immunizations:
Hepatitis A and B
Smallpox
Polio
Diphtheria
Influenza
Measles
Pertussis

Prior to cutaneous rash child may have flu like symptoms which may include upper respiratory tract symptoms ( pharyngitis ), low grade fever and malaise. When it is associated with viral infection like Epstein-Barr virus, Hepatitis B and Cytomegalovirus acute hepatitis may be present.

Gianotti Crosti rash develops over the course of 3-4 days. The rashes are usually dull, pale, deep red or pink to flesh colored papules or papulo-vesicular ranging from 1-10mm in diameter. The rash may primarily be localized on the thigh and buttocks followed by extensor surface of arms and finally may appear on face. The rash rarely appears on trunk, elbows, palms, knees and soles, although few cases have been reported. The rash is usually not itchy or in some cases may be mild itchy. The rash usually last for 2-4 weeks but may last as long as 4 months.

Other findings during examinations may be swelling of the axillary or inguinal lymph nodes, enlargement of liver and spleen, which may persist for several months.

Investigations:
Usually, no lab tests are needed to diagnose the case, but to find the definitive cause your doctor may perform some laboratory tests. A skin biopsy, liver enzymes or other serologic tests may be required.

Treatment of Gianotti-Crosti Syndrome

Gianotti-Crosti disease is harmless and self limited conditions, so no treatment is required. Treatment is mainly focused on controlling itching and symptomatic relief and treatment of any associated conditions or to prevent any further complications.

For symptomatic relief from itching, oral antihistamines or any soothing lotions like calamine or zinc oxide may be used. Topical or systemic steroids are not recommended, until and unless required for some very severe cases. Antihistamines and steroids doesn’t speed up the disease recovery but will relief the discomfort.

If there are any associated conditions like streptococcal infections, antibiotics may be required. Mild fever and discomfort may be relief with some antipyretic medications (aspirin is not recommended in child below 12 years). If there is any liver involvement consultation with pediatric gastroenterologist may be required.

There are no any long term complications with Gianotti-Crosti syndrome. Lesion usually resolves with in 4-5 weeks. If it is associated with hepatitis B continue follow-up with your doctor may be required as directed by your doctor.