A. Fauconneau

Acquired dermal melanocytosis of the back in a Caucasian woman.

To the Editor: Dermal melanocytoses are a broad group of affections in which scattered dendritic or spindle-shaped melanocytes are present in the dermis and result in a blue-greyish pigmentation. We report the case of an acquired dermal melanocytosis (ADM) on the back of an adult white woman. A 34-year-old woman presented with a blue-greyish hyperpigmentation of the upper back that appeared when she was a teenager (Fig. 1). It was not symptomatic. The patient did not report any infection or medicine-taking at the time the lesion arose. The clinical examination was otherwise normal. Histopathological examination of a punch biopsy showed a normal epidermis and scattered mature melanocytes in the dermis close to elastic fibers and collagen bundles (Figs. 2A, B). Immunostaining with A103/melanA antibody confirmed these cells were melanocytes (Fig. 2C). These findings were consistent with the diagnosis of ADM. The location was unusual and did not meet criteria for any previously described form. The group of dermal melanocytoses comprises congenital and acquired forms. Several entities are described regarding location, age of onset, and clinical course. Although Mongolian spot is located in the lumbosacral area and regresses during childhood, Ito’s naevus is typically located on the shoulder, neck, and scapular region, and Ota’s naevus is located on the face. Acquired forms are rare and occur mostly in Asian woman, usually on the face. They include acquired bilateral naevus of Ota-like macules (Hori naevus) and acquired unilateral Ota naevus (Sun naevus). Extrafacial ADM are even rarer and have been reported on the back, limbs, or extremities. They appear in childhood or early adulthood and only rarely in older adults. These lesions are benign, and very few cases of malignant evolution have been described. Their pathophysiology remains poorly understood. It is widely thought that melanocytes locate in the dermis as a result of an aborted migration during the embryonic period. It is less likely that melanocytes come from the basal layer of the epidermis ‘‘dropping off’’. Interaction with collagen bundles and elastic fibers seems fundamental in the pathogenesis. Ultrastructural studies have indeed evidenced an extracellular sheath around melanocytes in Mongolian spot that shrinks as the lesion disappears. On the other hand, the persistence of this sheath in other lesions might explain why they are permanent. The existence of acquired lesions is more intriguing. Immature ‘‘dormant’’ melanocytes could be present in the dermis from birth and activate later in life. Mizushima et al found such ‘‘dormant melanocytes’’ in the perilesional skin of a patient with ADM. It is still unknown which signal activates the melanin-producing pathway of these cells, although UV rays, hormonal factors, and trauma have been incriminated. Interaction with collagen and elastic fibers could also be involved. Last, the clear predominance of ADM in Asian women and familial cases suggests the role of genetic factors. Treatment is elusive given the depth and the extent of the lesions, although laser treatment provides good results. Combined protocols aimed at FIGURE 1. Diffuse blue-greyish pigmentation of the upper back.

Complete Remission of Squamous Cell Carcinoma After Treatment With Panitumumab in a Patient With Cetuximab-Induced Anaphylaxis.

observed reaction is also doubtfully drug related, since there were no liver test abnormalities found. The dermatophytid (id) reaction was excluded by the following observations: First, clinical lesions of id reactions are typically intensely pruritic and develop quite distantly from the site of infection.6 In the present case, the patient denied pruritus, and the exacerbation involved the primary lesions without production of any new ones. Second, in id reactions, no fungal forms are recovered from the lesions; in the present case, the patient’s lesions yielded fungal growth. Third, over the course of id reactions, no generalized symptoms (eg, fever), as seen in this patient, are normally observed. Altogether, this report presents an unusual case of a paradoxical reaction resembling, to some extent, the JHR, after treatment of dermatophyte infection with terbinafine.

Allergic hypersensitivity to red meat induced by tick bites: a French case report

An increasing number of cases of delayed anaphylactic reactions after the consumption of red meat have been reported in the United States but few similar cases have been reported in Europe. We report herein a French observation. A 54-year-old man first developed generalized urticaria, tachycardia, abdominal pain, nausea and vomiting 4 hours after eating beef kidneys. He subsequently had several similar episodes after eating beef, lamb and pork meat. He ate chicken and fish without problems. He did [...]