Extensive hyperpigmented plaques in a chinese singaporean woman: a case of cutaneous plasmacytosis.

Cutaneous plasmacytosis is a rare disease entity presenting with multiple extensive red-brown plaques, histopathology showing marked hyperplasia of mature polyclonal plasma cells, and polyclonal hypergammaglobulinemia on serum protein electrophoresis, in the absence of an underlying secondary cause. We report in this article the first case of cutaneous plasmacytosis from Singapore. A 33-year-old Chinese woman presented with mildly pruritic reddish brown papules and plaques over her trunk and arms for 2 years. Physical examination, laboratory investigations, and radiographic examination were negative for systemic involvement and lymphadenopathy. Serum immunoelectrophoresis showed polyclonal hypergammaglobulinemia with immunoglobulin G and immunoglobulin A. Two sets of skin biopsies performed 2 years apart essentially showed similar histopathological findings of a superficial and deep perivascular infiltrate with numerous mature plasma cells and small typical lymphocytes. There were lymphoid follicles with well-formed germinal centers and mantle zones, surrounded by mature lymphocytes. No light chain restriction was present on immunohistochemistry, and polymerase chain reaction for heavy chain gene rearrangement was negative for monoclonality. Despite potent topical corticosteroids and 8 months of phototherapy with narrow band ultraviolet light, there was no improvement. Intralesional triamcinolone injections to a few lesions afforded temporary relief of itch and flattening of lesions.

Contact dermatitis: a common adverse reaction to topical traditional Chinese medicine.

BACKGROUND: Over the past decade, there has been an increase in the use of topical traditional Chinese medicine (TTCM). The most common adverse event seen in the use of TTCM is contact dermatitis. This retrospective study was designed to determine the types of commonly used TTCM in Singapore causing contact dermatitis. METHODS: We retrospectively reviewed the case notes of 10 patients seen at the National Skin Centre over a 4-month period with a diagnosis of adverse cutaneous reactions to TTCMs. RESULTS: A total of 10 patients were diagnosed with contact dermatitis to TTCM at our institution over a 4-month period. The clinical manifestation ranged from eczematous lesions to urticarial plaques and blisters. Five of these patients were patch-tested to our standard series, our in-house TTCM series, as well as to the TTCM they had used. The other five patients declined patch testing. The results of patch testing confirmed the diagnosis of allergic contact dermatitis in three of the tested patients. Negative patch testing results inferred the diagnosis of irritant contact dermatitis to TTCM in the other two patients. Two of the patients with positive patch tests also had a positive reaction to balsam of peru and fragrance mix. The three positive patch tests were all caused by medicated oils. CONCLUSIONS: These results suggest it is likely that essential oils present as constituents of the medicated oils could be the possible allergen. The study also confirms that contact dermatitis is a common adverse event associated with the use of TTCM.