As its name implies, papular acrodermatitis of childhood clinically manifests as an acute, symmetric eruption of flat-topped papules in an acral distribution. These monomorphic papules most commonly occur on the extensor surfaces of the extremities. Arms are more commonly involved than legs. The face, buttocks, palms, and soles may also be affected. The trunk and scalp are relatively spared, as are the popliteal and antecubital fossae. However, the involvement of any of these areas does not preclude the diagnosis of papular acrodermatitis of childhood. The lesions are usually pale pink to flesh-colored and 1 mm to 10 mm in size. The lesions tend to be larger in younger children and smaller in older children and adolescents. Rarely, lesions may be vesicular or hemorrhagic. They are firm and discrete. Rarely, the lesions can become confluent over pressure points like knees and elbows. Koebner phenomena, the accentuation of lesions at sites of trauma, has also been reported. Mild-to-moderate pruritus may be present. Symptoms frequently last 2 to 4 weeks. In some cases, new lesions may continue to appear for up to 8 to 11 weeks after onset of illness. Importantly, the appearance of the rash itself may not help to distinguish the variously associated etiologies of papular acrodermatitis of childhood; however, careful assessment of associated or antecedent symptoms is essential for recognizing possible infectious triggers that may require further evaluation or isolation. Usually, the rash resolves without any residual effects or scarring. Occasionally, hyperpigmentation or hypopigmentation may persist after the rash resolves.[7][13][14][15] There is no associated mucosal enanthem but mucocutaneous features of the underlying viral trigger may be present.[15]

Fever, lymphadenitis, and other symptoms such as hepatosplenomegaly or pharyngitis may be seen in association with the rash or preceding it. This is consistent with a variety of viral triggers for this entity. There may also be a history of vaccination preceding the onset of the rash.[13][16] There are no specific laboratory findings seen in papular acrodermatitis of childhood. However, modest lymphocytosis or lymphopenia and elevated liver enzymes may be seen in Epstein-Barr virus, cytomegalovirus, or hepatitis-associated disease.[13]

In general, papular acrodermatitis is a clinical diagnosis with no laboratory testing indicated unless there are symptoms or physical exam findings, such as hepatomegaly, to suggest an underlying viral illness, such as hepatitis, that may require further management. Diagnostic criteria have been proposed and include the following symptoms:

• Lesions lasting at least 10 days;
• 1 mm to 10 mm papules or papulovesicular lesions with involvement of three of the four following sites: extensor surfaces of the forearms, extensor surfaces of the legs, cheeks, or buttocks;
• Symmetrical distribution of lesions.

Practitioners may need to further evaluate the causative virus in children who are immunocompromised or who reside in endemic areas. If a patient presents with jaundice, hepatomegaly, or generalized lymphadenopathy, evaluation for other viral infections, including hepatitis B or Epstein-Barr virus, may be indicated. Rarely, a skin biopsy may be performed to exclude other conditions in immunocompromised or other high-risk patients. Normally, biopsy findings are non-specific, with dermal perivascular mononuclear cell infiltrates and capillary endothelial swelling.[17][18]

Practitioners should reassure patients that papular acrodermatitis on its own is a benign and self-limited illness. The majority of cases spontaneously resolve without active intervention. Symptomatic management of itching may be helpful. Patients may use emollients or oral antihistamines. Since infectious agents do not directly cause skin lesions, mild to moderate potency topical steroids may be used in patients who fail to achieve relief of itching with emollients and oral antihistamines. However, treatment with topical steroids or oral antihistamines does not shorten the course of illness. Any underlying disorder, such as hepatitis B, that requires further management should be addressed. Lesions resolve without scarring although post-inflammatory pigmentary alteration may persist in some patients.[19]

The differential diagnosis of papular acrodermatitis includes other viral exanthems such as erythema infectiosum and Hand, Foot, and Mouth disease, insect bites, scabies, papular urticaria, atopic dermatitis, erythema multiforme, Langerhans cell histiocytosis, lichenoid dermatoses, and IgA vasculitis.

Papular acrodermatitis of childhood is a benign and self-limited disease that typically persists for 10 days to 6 months. The majority of skin manifestations resolve within 2 weeks to 2 months. Extracutaneous manifestations tend to persist longer than cutaneous lesions. Recurrences are rare.[16][20][21]

Post-inflammatory hypopigmentation or hyperpigmentation may occur in darker skin phenotypes and persist for up to 6 months. Permanent scarring is uncommon. Complications may arise in relation to the underlying viral etiology.[13][22]

It is important to reassure parents about the benign nature of papular acrodermatitis of childhood to avoid unnecessary invasive testing or treatments. Further laboratory work-up is only indicated in high-risk patients, including those who are immunocompromised or from hepatitis B endemic areas. Additional testing is also suggested in those with extracutaneous symptoms suggestive of an underlying viral etiology such as Epstein-Barr virus. 

It is not recommended to exclude children from daycare, school, or social activities.

Healthcare workers, including nurse practitioners and clinicians, need to be aware that papular acrodermatitis of childhood is a benign viral-induced skin disorder. It is often confused with other skin infections of childhood. If there is any doubt about the diagnosis, the patient should be referred to a dermatologist. Papular acrodermatitis of childhood is not person-to-person transmissible and does not require isolation beyond standard precautions or restrictions from school or other community activities. However, the associated viral infection may be contagious, thus isolation may need to be considered based on other symptoms suggestive of infectious disease. The dermatologist and dermatologist nurse specialist should provide a team effort to educate patients and their families about the disease and the necessary precautions. [Level V]