Solitary mastocytoma: tooth eruption as triggering factor

Abstract

A 2-month-old white male infant presented with a slightly infiltrated, brownish-erythematous plaque on the left arm a few days after birth (following normal physiologic pregnancy and parturition). His parents noted the development of a flaccid bulla on the site of the lesion after a fever and sought the aid of a specialist. The child presented no other general symptoms. At presentation, there was a blood serum-filled flaccid bulla surrounded by seemingly healthy skin (Fig. 1). Rubbing of the skin surrounding the bulla produced a hive-like reaction (Darier's sign). With the suspicion of a cutaneous mastocytoma, an incisional cutaneous punch biopsy was obtained (4 mm in diameter). Figure 1. A blood serum-filled flaccid bulla surrounded by seemingly healthy skin on the left arm of a 2-month-old white male infant Download figure to PowerPoint Histopathologic examination showed a monomorphous and dense proliferation of mast cells within the superficial and deep dermis. Neoplastic cells displayed moderately abundant, oval- or polygonal-shaped cytoplasm and round to oval nuclei (Fig. 2). The nuclei were characterized by clumped chromatin and indistinct or inapparent nucleoli. The cytoplasm was filled with small, faintly visible, eosinophilic or amphiphilic granules which stained metachromatically with Giemsa stain (Fig. 3). Scattered eosinophils were observed throughout the lesion. A final diagnosis of nodular mastocytoma was made. Figure 2. Hematoxylin and eosin stain showing a dermal monomorphous proliferation of cells characterized by moderately abundant, oval- or polygonal-shaped cytoplasm and round to oval nuclei (original magnification, ×20) Download figure to PowerPoint Figure 3. Giemsa stain showing metachromatic small granules within the cell cytoplasm (original magnification, ×20) Download figure to PowerPoint Having followed the lesion's evolution for 3 years, we have observed that it has been affected periodically by blistering, together with sudden episodes of flushing lasting 15–20 min, in the presence of triggering factors such as fevers or vaccinations. The most recent episodes occurred between the age of 15 and 24 months, and were associated with the eruption of deciduous teeth. Over the past few months, with the patient now approximately 3 years of age, the lesion has grown progressively lighter and is beginning to disappear (Fig. 4). Figure 4. After the age of 2 years, the mastocytoma became progressively lighter and smaller Download figure to PowerPoint