American Journal of Dermatopathology最新文献

Background: Vitiligo is a skin disorder characterized by the loss of melanocytes from the epidermis. Cysteine x cysteine motif chemokine ligand 10 (CXCL10) is linked to the Th1 pattern and has been suggested as one of the most relevant chemokine axes that promote T-cell migration in different autoimmune and inflammatory processes. The aim of this study was to assess the immunohistochemical (IHC) expression of CXCL 10 in skin lesions of patients with vitiligo to explore its possible role in the pathogenesis of the disease.

Methods: In this prospective, case-control study, we examined biopsies from the lesional skin of 20 patients with vitiligo for IHC expression of CXCL 10: 10 patients presented with stable nonsegmental vitiligo (group A), 10 patients presented with active nonsegmental vitiligo (group B), and 10 apparently healthy volunteers were examined as controls (group C).

Results: Nine patients in group A had mild IHC expression of CXCL 10 (+1) and 1 patient had moderate expression (+2). In group B, 8 patients had strong expression of CXCL 10 (+3), and the remaining patients had moderate expression (+2). However, there was no expression of CXCL 10 in all skin specimens in the control group.

Conclusions: CXCL10 IHC expression was increased in vitiligo lesions indicating a possible role in the pathogenesis of disease. The expression was significantly increased in active vitiligo compared with stable vitiligo.

Abstract: There is a paucity of data regarding porokeratosis confined to the penis and scrotum. We evaluated our single-institutional experience regarding this entity. We interrogated our pathology archive for all specimens from the penis or scrotum, signed out as porokeratosis between 2000 and 2022. Clinical and histopathological features were reviewed, including the number of cornoid lamella(e) per tissue profile and squamous dysplasia. Nine patients were included in the study. The median age at the time of diagnosis was 51 years. Multiple lesions were present in 3 patients. Six patients had exclusively penile involvement, whereas 2 patients had exclusively scrotal involvement. One patient had multiple lesions consistent with porokeratosis ptychotropica, extending from the scrotum to the buttocks and perineum. Clinically, a collarette of scale was noted in 3 patients and diagnosis of porokeratosis was considered in 1 patient before biopsy. Histopathologically, 2 patients exhibited multiple cornoid lamellae in the same profile and 1 patient had follicular cornoid lamellae. Focal squamous dysplasia was only present in 1 patient. Follow-up was available for 5 patients (median duration: 35 months). In 4 patients, the lesions were removed completely during the shave biopsy procedure. At the past follow-up, there were no signs of recurrence or malignant transformation to squamous cell carcinoma in any patient. Porokeratosis involving the penis and/or scrotum may be elusive to diagnosis based on clinical features alone, emphasizing the role of histopathological examination. Increased awareness of this entity may help better delineate its clinicopathological presentation and appropriate classification.

Abstract: Cutaneous larva migrans (CLM) is an ectoparasitic infestation predominantly caused by nematodes, specifically Ancylostoma braziliense and Ancylostoma caninum , found in tropical and subtropical regions. Although follicular involvement by the parasite is a rare manifestation, with approximately 20 cases reported in the English literature, its pathogenesis remains underexplored. The present study reports 2 cases of CLM presenting with follicular involvement in patients with pruritic lesions following travel to subtropical areas. The first of them is a 32-year-old woman who developed an abdominal skin lesion subsequent to a trip to Thailand and the second is a 28-year-old woman who exhibited a knee lesion after a volunteer mission in Senegal. Histologic examination revealed characteristic features of CLM, such as nematode larvae traversing the hair follicle. The hookworm larvae were observed creating tunnels within the external root sheath. In addition, they were interfacing with the vitreous layer, sparing the perifollicular connective tissue sheath and the Henle layer, and approaching the vicinity of the hair bulb. The application of skin ultrasound to guide the biopsy facilitated the visualization and identification of the parasite within the follicle in the latter case. This study not only underscores follicular involvement in CLM but also provides insights into its anatomopathological presentation and spread through the hair follicle.

Abstract: Anetoderma is an uncommonly reported dermatosis clinically characterized by discrete skin lesions resulting from elastic fiber loss within the dermis. Although primary anetoderma has been considered idiopathic, a range of associated disorders, particularly prothrombotic abnormalities, have been reported. We present a 79-year-old woman with a heterozygous Factor V Leiden mutation who developed anetoderma shortly after COVID-19 infection complicated by a thromboembolic event. Our patient adds to the literature on the occurrence of anetoderma in the setting of infection and/or a prothrombotic disorder.

Abstract: Interdigitating dendritic cell sarcoma is a rare, aggressive hematological malignancy primarily originating in lymph nodes, with only 10 reported cases presenting in the skin (primary cutaneous interdigitating dendritic cell sarcoma). Past presentations showed erythematous nodules on the proximal extremities, back, or face. Morphologically, these neoplasms are similar to melanomas and other dendritic cell (DC) tumors, making their diagnosis difficult. Here, we present 1 case of primary cutaneous interdigitating dendritic cell sarcomas and another 1 of malignant indeterminate dendritic cell tumor (indeterminate DC sarcoma). The first case is an 83-year-old man who presented with recent ulceration and bleeding of an asymptomatic, slow growing lesion on his right thigh with biopsy revealing a large, well-circumscribed polypoid spindle cell tumor in the dermis with atypical cells with vesicular nuclei in a lymphoplasmacytic background and immunohistochemistry positivity for CD45, CD68, S100, and Cyclin D1. The second case is a 74-year-old man who presented with a progressively darkening and enlarging abdominal skin lesion with biopsy revealing a diffuse infiltrate of atypical poorly differentiated pleomorphic nuclear cells and immunohistochemistry positivity for S100, CD1a, CD56, CD43, cyclin D1, CD31, CD4, and BRAF V600E. Our findings contribute to expand the reported literature on primary cutaneous DC sarcomas.

Abstract: Nail involvement in Langerhans cell histiocytosis is rarely reported in the literature. According to the reported cases, it is believed that the involvement of nails has a poor prognosis because of multisystem involvement. Performing a nail bed biopsy might be challenging for children. We report a child in whom nail bed biopsy served as the sole clue to the diagnosis of Langerhans cell histiocytosis in absentia of skin clue on a background of advanced multisystem involvement.

Abstract: Follicular hybrid cysts are uncommon entities derived from 2 or more components of the folliculo-sebaceous-apocrine unit. The pathogenesis of follicular hybrid cysts is uncertain; however, they are proposed to derive from the multipotent nature of follicular stem cells. Myotonic dystrophy type 1 is an inherited muscular dystrophy caused by an unstable trinucleotide repeat expansion in the myotonic dystrophy protein kinase gene, notably associated with multiple pilomatricomas. We report a novel case of multiple follicular hybrid tumors presenting in association with myotonic dystrophy type 1. We suspect that multipotent follicular stem cells, under the influence of the hypermutability phenotype present in myotonic dystrophy type 1, contributed to the pathogenesis of multiple follicular hybrid tumors in our patient.