: Syphilis, a sexually transmitted disease caused by the spirochete Treponema pallidum, can affect nearly every organ system in the body. In particular, skin manifestations of secondary syphilis are common but nonspecific and can be a true masquerader of other skin disorders. Concomitant infection with HIV has been increasing and may cause even more unusual skin presentations. We present a patient with the atypical combination of palmoplantar keratoderma and ocular symptoms that closely resembled reactive arthritis (or Reiter's syndrome). When evaluating patients with HIV infection, clinicians should maintain a high level of suspicion for syphilis to accurately diagnose and treat this curable but potentially fatal disease.

: Direct immunofluorescence (DIF) is an important tool for evaluating bullous autoimmune and connective tissue disorders.We report 21 cases of pemphigus vulgaris, bullous pemphigoid and lupus erythematosus that were investigated by performing DIF on scalp hair follicles. The study was done using a simplified technique of preparing the hairs for DIF testing. The anagen hairs tested positive in pemphigus vulgaris patients while the telogen hairs were negative. In bullous pemphigoid and lupus erythematosus cases hair DIF presented negative results.Hair DIF has the potential of taking the place of skin or mucosal DIF in pemphigus patients if performed on anagen hair follicles. The technique used to perform hair DIF is important in obtaining reliable results and eliminating the possibility of generating false-negative testing. Larger studies are needed in order to validate this method.

BACKGROUND::

Angiosarcoma (AS) is a rare soft tissue sarcoma showing endothelial differentiation as indicated by morphology and expression of CD31 (blood), D2-40 (lymphatic), factor VIII, and CD34 (both). We sought to examine the pattern of immunohistochemical markers of differentiation in AS and correlate these with outcome.

DESIGN:

: An AS tissue microarray (n = 70 specimens) was constructed for immunohistochemical analysis of CD31, CD34, factor VIII, D2-40, and pan-cytokeratin. Samples on this array were linked to clinicopathologic and outcome data for these patients. Univariate analyses were used to explore disease-specific survival (DSS) factors.

RESULTS::

Nine metastatic, 23 localized, and 4 recurrent cases were included. Information about the tissue status (ie, primary or metastasis) was unavailable in 4 patients. Primary sites for the tumor included bone (n = 1), breast parenchyma (n = 11), breast skin (n = 4), heart (n = 5), skin (n = 8), soft tissue (n = 7), and unknown (n = 3). Three patients presented with multifocal disease (primary sites in these patients included breast, skin, and soft tissue). Metastatic sites included lung, bone, lymph nodes, brain, liver, and parotid. Of the 40 cases, 8 (20%) showed a pure or predominant epithelioid histology. Of the biomarkers evaluated by tissue microarray, 92% of tumors expressed at least one endothelial marker (factor VIII = 83%, CD31 = 80%, CD34 = 63%, and D2-40 = 43%) with 88% expressing 2 or more markers. Eighty-eight percent of tumors expressing D2-40 coexpressed CD31, an unusual combination in normal vessels. No endothelial marker clearly associated with disease-specific survival. Fifty percent (4/8) of epithelioid cases and 9% (3/32) of nonepithelioid cases showed keratin expression.

CONCLUSIONS::

Unusual patterns and loss of endothelial markers are common in AS, suggesting use of multiple markers in challenging cases and perhaps indicating important biologic characteristics.

: The use of anaplastic lymphoma kinase antibodies (ALK1) as a diagnostic aid has expanded since becoming a routinely available immunohistochemical stain. Because the skin may be the site of a wide variety of hematolymphoid and fibroblastic proliferations, dermatopathologists commonly use ALK1 as part of a broader staining panel in diagnosing soft tissue and cutaneous hematolymphoid neoplasms. Furthermore, new entities and differential diagnostic contexts are emerging, which broaden the utility of ALK1 immunohistochemistry. We review the expanding role of ALK1 immunohistochemistry in contemporary dermatopathology.

: Molluscum contagiosum (MC) can rarely show follicular neogenesis as a result of proliferation of virus-infected basal cells. We report a case of molluscum contagiosum showing multifocal areas of primitive follicular induction involving the adjacent surface epidermis. The underlying dermis showed histological features suggestive of secondary anetoderma. The pathogenetic mechanisms behind development of these microscopic features and the putative link between follicular induction and secondary anetoderma are explored. Awareness of this unusual phenomenon will be helpful in avoiding a misdiagnosis of a superficial basal cell (trichoblastic) carcinoma in such cases.

: A 23-year-old male affected of recessive dystrophic epidermolysis bullosa presented with a 2-month history of a growing verrucous plaque on the right flank. The clinical features and evolution suggested the diagnosis of cutaneous squamous cell carcinoma. Histopathological examination showed hyperkeratosis, parakeratossis, and verrucous acanthosis and numerous large xanthoma cells in the papillary dermis. Reflectance confocal microscopy disclosed the absence of epidermal atypia and the presence of aggregates of reflecting cells at dermal-epidermal junction and upper dermis. These cells were ultrastructurally characterized and corresponded to foamy histiocytes. Verruciform xanthoma is a benign reactive lesion that has occasionally been reported to develop in chronically eroded areas in patients with recessive dystrophic epidermolysis bullosa. In this group of patients, verruciform xanthoma may clinically mimic cutaneous squamous cell carcinoma and a correct diagnosis is crucial to avoid inappropriate aggressive therapeutic approaches. In vivo noninvasive image technologies such as reflectance confocal microscopy may be helpful diagnostic tools in this clinical setting.

: Two cases of a pseudoherpetic variant of Grover disease are presented. The first patient was a 60-year-old woman who had high fevers in combination with right lower lobe pneumonia. She developed an itchy papulovesicular rash on her back and upper abdomen. The second patient was a 68-year-old woman who while bedridden developed an itchy papulovesicular rash on her back. Vesiculobullous forms of dermatitis were clinically suspected in both cases, and herpetic vesicles were the lead diagnosis in one case. Pathologically, lesions from both patients revealed intraepidermal fluid-filled vesicles that at scanning magnification raised the suspicion of herpetic lesions. At higher magnification, acantholytic cells, some seemingly multinucleated, could be ppreciated. However, immunohistochemistry for herpes simplex virus and varicella zoster virus antigens proved negative. Moreover, some of the lesional cells revealed dyskeratosis more typical of the spongiotic/vesicular variant of Grover disease, and accordingly, this diagnosis was eventually established in both patients. Recognition of the pseudoherpetic variant of spongiotic/vesicular Grover disease is important in determining correct treatment, and therefore, subtle clues to its diagnosis should be sought in evaluation of such lesions.

: The authors report a small case series of hybrid nerve sheath tumors occurring in the setting of type 1 neurofibromatosis. Four lesions were benign and consisted of plexiform neurofibromas with considerable areas of perineuriomatous differentiation in patients with type 1 neurofibromatosis. In these lesions, biphasic (Schwannian and perineuriomatous) differentiation was apparent on immunohistochemistry, with the perineuriomatous areas staining for epithelial membrane antigen, glut-1, and claudin-1 and being negative for S-100 protein. Three patients were members of a single family, with a history of various malignant neoplasms. Included in the series is 1 hybrid lesion in which neurofibromatous and perineuriomatous areas were clearly visible on hematoxylin- and eosin-stained slides. The lesion was unique in that it manifested malignant change in the S-100 protein-positive component, which was classified as malignant peripheral nerve sheath tumor. The malignant component showed areas with an epithelioid cell morphology.