Onychomatricoma on the fourth toenail: A rare tumor in a rare localization.

Onychomatricoma is a rare benign tumor of the nail matrix, characterized by finger-like projections that invade the nail plate. The fingernails of Caucasian women are most commonly affected. Because this tumor can easily mimic other more prevalent ungual diseases, it is crucial to be acquainted with its characteristic clinical and histopathologic features. The authors present a case of a 40-year-old man with an onychomatrichoma in the fourth left toenail, which was initially misdiagnosed and treated as onychomycosis.

Nailfold capillaroscopy with USB dermatoscope: A cross-sectional study in healthy adults.

BACKGROUND: Nailfold capillaroscopy (NFC) is a convenient method for studying capillary morphology in the proximal nailfold (PNF) and is used for the evaluation of connective tissue and other diseases affecting the microvasculature. However, capillary density and morphological patterns in healthy individuals are largely unknown and this compromises the evaluation of the microvasculature in disease states. OBJECTIVE: To describe and quantify the morphological characteristics of nailfold capillaries in healthy adult Indians. METHODS: A USB 2.0 dermatoscope (Dinolite AM413ZT) with polarizing light was used to study nailfold capillary characteristics in 50 consecutive healthy adult individuals. NFC was performed on all 10 fingers. Images were assessed for both quantitative and qualitative features. RESULTS: The mean capillary density in healthy Indian adults was 7.63 ± 1.12 capillary/mm. Tortuosity (22%), meandering capillaries (14%) and microhemorrhages (14%) were frequently seen in these individuals. LIMITATION: The small sample size limited a conclusive determination of statistically significant differences in NFC findings with respect to gender and age. CONCLUSION: NFC with a USB dermatoscope is a useful technique for studying the PNF capillaries. The normal PNF capillary density in healthy Indian adults was 7.63 ± 1.12 capillary/mm. Capillary alterations such as tortuosity, meandering capillaries and microhemorrhages are seen in a significant number of healthy individuals.

Second to fourth digit ratio in female patients with acne vulgaris: Could it be a predictor of androgen receptor status?

BACKGROUND: Second to fourth digit (2D:4D) ratio is the ratio of index to ring fingers length. It reflects prenatal androgen exposure and sensitivity. Androgens are important in the pathogenesis of acne vulgaris, This ratio may therefore be of significance in determining the expression of androgen receptors. AIM: To investigate the relationship between second to fourth digit ratio and androgen receptor expression in female patients with acne vulgaris and to assess its association with clinical aspects of acne vulgaris. METHODS: Females patients (n = 352) with different degrees of acne vulgaris severity and 168 age-matched females were enrolled. Right, left and total second to fourth digit ratios were calculated. Biopsies from all participants were processed for androgen receptor expression by immunohistochemical method. RESULTS: Right, left and total second to fourth digit ratios were significantly lower in acne vulgaris patients than controls (P < 0.001 for all), and each of them had a significant negative correlation with duration of acne vulgaris (P < 0.001; P = 0.013; P < 0.001, respectively). Androgen receptors were detected in epidermal keratinocytes, hair follicles, sebaceous glands and fibroblasts. Right second to fourth digit ratio showed a negative correlation with androgen receptor H score of keratinocytes (r = -0.28;P = 0.02), hair follicles (r = -0.22; P = 0.05) and fibroblasts (r= -0.37;P = 0.001), while left second to fourth digit ratio demonstrated negative correlation with androgen receptor H score of sebocytes (r = -0.397; P < 0.000) only. LIMITATIONS: Lack of follow-up and absence of male participants were the main limitations of this study. CONCLUSION: A masculine second to fourth digit ratio in female patients could anticipate acne vulgaris development, its duration and severity. Moreover, this ratio is associated with an upregulation of cutaneous androgen receptors. Taken together, second to fourth digit ratio could help in designing plans for treatment of acne vulgaris.

Acro-osteolysis.

Acro-osteolysis is an osteolysis of the distal phalanges of the hands and feet and can affect the terminal tuft or the shaft of the distal phalanx (transverse or band acro-osteolysis). It is often associated with distal digital ischemia, digital calcinosis, or severe sensory neuropathy. Acro-osteolysis has been associated with a heterogeneous group of disorders, including occupational activities, infections, rheumatic disorders (systemic sclerosis, psoriatic arthritis), endocrinopathies, genetic disorders, and lysosomal storage disorders. Plain radiography is the gold standard for the detection of acro-osteolysis.

Histoid leprosy with giant lesions of fingers and toes.

This work was conducted at the Facultad de Medicina, Universidad de La Sabana, and at the Facultad de Medicina, Universidad Surcolombiana. Histoid leprosy, a clinical and histological variant of multibacillary leprosy, may offer a challenging diagnosis even for experts. An 83-year-old woman presented with papular, nodular and tumor-like lesions of 3 years of evolution, affecting fingers, toes, hands, thighs and knees, and wide superficial ulcers in her lower calves. Cutaneous lymphoma was suspected. A biopsy of a nodule of the knee showed a diffuse dermal infiltrate with microvacuolated histiocytes, moderate numbers of lymphocytes and plasma cells. Cutaneous lymphoma was suggested. Immunohistochemistry (IHC) showed prominent CD68-positive macrophages, as well as CD3, CD8 and CD20 positive cells. Additional sections suggested cutaneous leishmaniasis. New biopsies were sent with the clinical diagnoses of cutaneous lymphoma, Kaposi´s sarcoma or lepromatous leprosy, as the patient had madarosis. These biopsies showed atrophic epidermis, a thin Grenz zone and diffuse inflammation with fusiform cells and pale vacuolated macrophages. ZiehlNeelsen stain showed abundant solid phagocytized bacilli with no globii formation. Abundant bacilli were demonstrated in the first biopsy. Histoid leprosy was diagnosed. The patient received the WHO multidrug therapy with excellent results. We concluded that Ziehl Neelsen staining should be used in the presence of a diffuse dermal infiltrate with fusiform and vacuolated histiocytes, which suggests a tumor, and an IHC particularly rich in CD68-positive macrophages; this will reveal abundant bacilli if the lesion is leprosy. A good clinical pathological correlation is essential to establish a proper diagnosis and management of the patient.