gms | German Medical Science

Objectives: Cutaneous manifestation of mastocytosis is more common in children than in adults, although the infrequency with which it is encountered and lack of awareness can cause considerable parental anxiety and a diagnostic challenge to paediatric hand surgeons.

We present this case to increase awareness and recognition of this condition to ease diagnosis and allow parents to be better counselled during treatment. Clinical photographs of the lesion will be presented.

Method: A seven month old male infant presented with a palmar lesion, first noticed at six weeks of age. Recurrent episodes of discharge and ulceration were noted with no recognised triggers. The infant had eczema, but was otherwise fit and healthy. Parents were originally from Bangladesh, but there had been no foreign travel since the child was born. There was no family history of or recent contact with infectious diseases.

On examination, there was an 8 x 8mm flesh-coloured, soft, popular, non-tender lesion in the right palm at the base of the ring finger. He displayed full range of motion in all his digits and the lesion was not fixed to underlying structures. Ultrasound demonstrated a 1 x 0.8 x 0.2cm disc-like hypoechoic area, suggestive of fluid content, with no intra-lesional vascularity or deep extension. Plain radiography was unremarkable. After joint dermatology review, an incisional biopsy was undertaken.

The biopsy demonstrated a sheet-like dermal mast cell infiltrate, extending to the under-surface of the epidermis and into the superficial subcutaneous tissue. The features were consistent with a cutaneous mastocytoma.

Results: The infant's care continued under the dermatology team. Cetirizine was required for symptomatic control. The biopsy site healed uneventfully.

Conclusion: Solitary mastocytoma is a relatively rare cutaneous tumour, which usually occurs, in the antenatal period or early in infancy. Its occurrence in the palm or sole is rare, although there are a number of case reports of lesions in the hand, including one of dorsal and three of palmar lesions.

Features in keeping with a cutaneous mastocytoma include Darier's sign, a wealing response to stroking of the lesion. Differential diagnosis can include xanthogranuloma, neurofibroma, haemangioma and granuloma annulare. Diagnosis is confirmed by histology, which shows an increased number of mast cells. The condition usually follows a mild course and resolves by adulthood. Symptomatic lesions may require topical steroids and intra-lesional triamcinolone injections.