Causes and risk factors:
The exact etiology of this condition is not known. Various hypotheses have been put forth. Genetic factor and certain environmental factors contribute to the same. A familial predilection is seen. It can also be an autoimmune disorder. Atopy is one of the predisposing factors. Infection, particularly the varicella, or trauma is another causative factor. Studies have shown that appearance of lichen striatus has been reported to occur after BCG and hepatitis B vaccine, after exposure to ultraviolet rays, and tanning beds can also result in this condition. One of the studies has also suggested that epigenetic mosaicism seems to be involved in the causation.
Clinical presentation:
The skin is commonly affected; however, affection of the nails can also occur. Lower extremity is the most common site of affection; the eruptions can also be seen on head, neck, trunk, and buttock regions. Sudden appearance of small red color eruptions or papules is the characteristic feature. The size of the eruption varies from 1-3 mm. It is either pale colored or can be reddish pink in color. Over a time of few days to a week these raised bumps join to form a linear band. In dark colored people, hypopigmented patches can be seen. Itching along with dryness can be one of the associated complaints.
Investigations:
Diagnosis is done on the basis of the symptoms narrated by the parents along with local examination carried out by the dermatologist. The characteristic appearance of the eruption is diagnostic. Histological examination and skin biopsy can be advised. Along with this, direct immunofluorescence test can be done.
Treatment:
This is a self-limiting skin infection which usually resolves over a time span of 3-12 months. Hence no medical intervention is needed. Soothing agents and emollients or topical steroids can be applied. Low dose of systemic steroids have also been found to give effective results. Photodynamic therapy can also be used.
Complications:
Post inflammatory hypopigmentation patches are seen.
When to contact a doctor:
Contact a dermatologist if one notices any eruptions.
System involved: Integumentary system.
Organ involved: Skin and tissue
