A Rare Case of Childhood-Onset Hailey-Hailey Disease at an Unusual Site.

Sir,

Hailey–Hailey disease is a rare and chronic recurrent disorder, inherited as an autosomal dominant trait. A 3-year-old boy presented with recurrent episodes of multiple vesicles over the right side of the lower back associated with mild itching for last one and a half years for which they sought treatment of unknown nature from a local practitioner and got relieved within a week or so. One month back, when the child was brought to the outpatient department of Sir Sundar Lal Hospital, he was prescribed oral and topical antibiotics as there was secondary infection. There was a marked improvement but post-inflammatory hyperpigmentation was present. After 2 weeks, the child was brought to us with vesicular eruptions at the same site. Examination revealed multiple erythematous papules and vesicles on an erythematous base coalescing to form a plaque with slight crusting, surrounded by hyperpigmentation over the right side of the lower back as shown in Figures 1 and 2. Nails, hair, and mucosa didn't show any abnormal features. The child was born by normal vaginal delivery. No aggravating or relieving factor could be elicited. Routine hematological and other laboratory investigations were within normal limits.

Figure 1

Showing the distribution of the lesion at the right lower back

Figure 2

Multiple papules and vesicles on an erythematous base coalescing to form a plaque with slight crusting and surrounding hyperpigmentation

Herpes simplex and Hailey–Hailey disease were kept in the differential diagnoses. Tzanck smear did not show any acantholytic cells or multinucleated giant cells. IgG antibodies against HSV1 and HSV2 were found to be mildly raised in the child but negative in mother. Skin biopsy and direct immunofluorescence (DIF) were advised. Histopathological examination [Figures 3 and 4] revealed intraepidermal acantholysis with numerous incompletely acantholytic cells that were seen within the blister cavity. The epidermis was hyperplastic and shows a suprabasal acantholytic blister at places with a tombstone pattern. Incomplete acantholysis extends to the hyperplastic epidermis where it was seen to involve more than half of its thickness. DIF was done in a biopsy specimen taken from perilesional skin adjacent to vesicles. It was negative for IgG, IgM, C1, and C3. Based on these clinical findings and histopathology, the case was diagnosed as a case of Hailey–Hailey disease.

Figure 3

Histopatholgy of the skin lesion (10X, H&E stain)

Figure 4

Histopatholgy of the skin lesion (40X, H&E stain)

Hailey–Hailey disease, also known as familial benign pemphigus, is relatively uncommon in India with an incidence of 1 in 50,000 and usually presents in the third decade although can occur at any age.[123] Hailey brothers described this condition for the first time in 1939.[4] The defect lies in ATP2C1 gene encoding Ca2+ ATPase which lies in Golgi. It is clinically characterized by recurrent vesicles that rupture, leaving painful fissures, and scaly erythematous plaques predominantly at sites of friction (neck, axilla, inframammary, groin, perineum).[15] Here, we report a case of Hailey–Hailey disease in a 3-year-old boy with the onset at one and a half years of age, at an unusual site. The differential diagnosis of Hailey–Hailey disease includes eczema, impetigo, fungal infection, and Candida infection. The aggravating factors are trauma, heat, sweating, and UV light; which were not found in our case. Family history is obtained in about two-thirds of patients that were not present in our case. The diagnosis was made on the basis of clinical features and histopathological examinations. Histopathology showed a “dilapidated brick wall” appearance which was in accordance with Hailey–Hailey disease.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.