Acta Derm Venereol 88191 Letters to the Editor Sir, Reversible skin hyperpigmentation is one of the pigmentary changes associated with vitamin B12 deficiency. It is observed in patients with megaloblastic, non-pernicious anaemia, mainly in those with dark-coloured skin (1-3).We describe here a case of a 21-year-old Greek woman in whom hyperpigmentation (reddish-brown colour) was confined to the lateral surfaces of the legs. Increased angiogenesis was observed histologically in these areas.
CASE REPORTA 21-year-old Caucasian female was referred to us because of gradually increasing hyperpigmentation on her legs, observed since she was 4 years old. The hyperpigmentation started from the inner thigh and had extended over the tibia over the past few years. She also reported developing concurrent "finger deformity".Her medical history included primary growth hormone deficiency, for which she had been treated with subcutaneous injections of growth hormone. She had been a vegetarian since she was 3 years old and did not consume any milk products.Physical examination revealed reticulated dark brown with reddish hue hyperpigmentation on both lateral surfaces of her legs (Figs 1a, 2A). Moreover, her fingers were in varying degrees of fixed flexion with impaired extension in all digits (Fig. 2B). The contractures were painless. No nail or tongue abnormalities were observed and neurological examination was normal.Routine investigations were within normal limits, with no changes in chronic B12 deficiency, except a low serum B12 concentration of 100 pg/ml (normal 160-900 pg/ml) and mild macrocytosis. Ht = 37.5%, Hb = 12.5 g/dl, MCV = 96 fl (normal = 78-95 fl), PLT = 250000, PT = 13.5 s, INR = 1, APTT = 35.6 s. Serum folate, Zn, ferritin, TIBC, T3, T4, TSH, DHEA, DHEA-S and ACTH were all within normal limits. The anti-intrinsic factor antibodies, anti-parietal cell antibodies, antimicrosomal thyroid and anti-thyrospherine antibodies, anti-gliadin and anti-tissue transglutaminase antibodies, anti-dsDNA, anti-ENA, RNP, anti-SM, SSA(Ro), SSB(Lo), antiJO1 and Ra-test were negative. Plain film radiological studies of her hands were normal, as was electromyography. The patient refused to undergo upper gastrointestinal endoscopy.Skin punch biopsies 4 mm in diameter were performed on her right crural and tibial areas. Microscopy showed increased numbers of basal cell layer melanocytes, as well as increased melanin granules in the basal layer and supral basal layer (Fontana stain). Multiple clusters of vessels CD34-positive (Fig. 3a,b) with a few lymphocytes and plasmacytes around them were observed in the dermis, as well as free melanin granules. Moreover, an increased number of fibroblasts and some giant cells were noted in the reticular dermis. Distortion of collagen fibres was found. Orcein (Shikata) staining revealed fragmented elastic fibres in the reticular dermis. There was an increased number of mast cells around the vessels. Vascular endothelial growth factor (VEGF) was weakly expressed by some endothelial and plasma cells. Pe...
