Localized bullous pemphigoid after knee replacement surgery.

Bullous pemphigoid (BP) most commonly presents as widespread, itchy, tense blisters in older patients. Localized bullous pemphigoid is a less common form of BP that can be more difficult to diagnose because of its similarity to more common conditions such as allergic contact dermatitis or bullous cellulitis. Prompt recognition of localized BP is important so that appropriate treatment can be started. We present a 57-year-old woman who presented with pruritic tense bullae overlying the surgical scar from a knee replacement 6 months prior on her anterior right knee. This case illustrates the potential for localized BP to be triggered by surgical procedures.

Multiple atypical vascular lesions following breast-conserving surgery and radiation.

Atypical vascular lesions (AVLs) of the breast are purple papules or nodules that have been reported in breast cancer patients following radiation treatment, typically presenting with fewer than 5 lesions at diagnosis. We report a patient with 29 lesions within previously irradiated breast tissue. Due to the large number of lesions and concern for development of angiosarcoma, the patient's case was brought before a multidisciplinary tumor board that decided she should undergo a radical mastectomy with flap reconstruction. We discuss the dermatologist's role in managing this complex and increasingly common disorder.

A Case of a Malignant Cutaneous Mixed Tumor (Chondroid Syringoma) of the Scapula Treated With Staged Margin-Controlled Excision.

Cutaneous mixed tumor (chondroid syringoma) is the cutaneous counterpart of pleomorphic adenoma of salivary glands, comprised of both epithelial and mesenchymal components. Malignant transformation is exceptionally rare, with only a few cases reported. We report a case of a malignant cutaneous mixed tumor in an 86-year-old white man who presented with a pink indurated plaque on his left scapula. He had a history of nonmelanoma skin cancers, a stage IB malignant melanoma of a lower extremity and Gleason 4 + 3 prostate cancer treated with brachytherapy, external beam irradiation, and bicalutamide. A shave biopsy was performed and histologic examination revealed infiltrative single-unit atypical cells and small ducts in a superficially transected sclerotic dermis suggestive of a poorly differentiated adenocarcinoma. No epidermal connection was identified. Immunohistochemical studies revealed that the tumor was positive for CK7, CAM5.2, and mCEA and negative for CK20, epithelial membrane antigen, P63, prostate-specific antigen, prostatic specific acid phosphatase, and alpha-methylacyl-coenzyme A racemase. A metastasis of the breast or upper digestive tract was favored, although a primary eccrine carcinoma was also considered. Imaging was performed and no other masses were identified. A slow Mohs excision was performed with negative margins. Microscopic examination revealed a biphasic neoplasm comprised of infiltrative epithelial strands and tubules consistent with an eccrine carcinoma in a hyalinized and chondromyxoid stroma within the dermis, arising from a well-circumscribed chondroid syringoma located in the deep dermis and subcutis. Areas of clear cell change, intracytoplasmic vacuolization, and mucin pools were noted. Multiple foci of perineural invasion were identified. Additional immunohistochemical studies revealed that the tumor was positive for S100 and negative for CK5/6, calponin, glial fibrillary acidic protein, GATA3, GCDFP-15, and mammoglobin. Based on the morphologic features and immunoprofile, this was diagnosed as a malignant cutaneous mixed tumor. This case highlights the importance of obtaining adequate tissue for histologic evaluation, as they can be confused with other skin neoplasms because of their clinically ambiguous presentations. Although rare, an accurate diagnosis is important given that long-term follow-up is recommended because of the risk of local recurrence and both lymph node and distant metastases.

Pityrosporum folliculitis: A retrospective review of 110 cases.

BACKGROUND: Pityrosporum folliculitis is an under-recognized eruption of the face and upper portion of the trunk that may be confused with, or occur simultaneously with, acne vulgaris. OBJECTIVE: We sought to characterize risk factors for Pityrosporum folliculitis, its clinical presentation, and its response to treatment. METHODS: A retrospective chart review was performed on all patients age 0 to 21 years seen at our facility from 2010 to 2015 with Pityrosporum folliculitis confirmed by a potassium hydroxide preparation. RESULTS: Of 110 qualifying patients, more than 75% had acne that had recently been treated with antibiotics, and when recorded, 65% reported pruritus. Clinical examination demonstrated numerous 1- to 2-mm monomorphic papules and pustules that were typically on the forehead extending into the hairline and on the upper portion of the back. The most common treatment was ketoconazole shampoo, which led to improvement or resolution in most cases. Some patients required oral azole antifungals. LIMITATIONS: This study was retrospective and relied on providers describing and interpreting the clinical findings and potassium hydroxide preparations. No standard grading system was used. CONCLUSION: Unlike classic acne vulgaris, Pityrosporum folliculitis was more common after antibiotic use. It presented as fine monomorphic, pruritic papules and pustules along the hairline and on the upper portion of the back, and it improved with topical or oral azole antifungal therapy.

Lichen planus pigmentosus in a blaschkoid distribution.

Lichen planus pigmentosus is a pigmentary disorder of unknown etiology, with diffuse hyperpigmentation of sun-exposed areas, more commonly seen in some ethnic and racial groups. We report an unusual case of lichen planus pigmentosus in a 40-year-old man with Fizpatrick type III skin that was present in a blaschkoid distribution on the trunk, a distribution that has been rarely reported. This unique presentation of lichen planus pigmentosus may contribute to better understanding of the etiology, as the blaschkoid distribution may reflect underlying cutaneous mosaicism that renders those cells more susceptible to an insult that results in lichen planus pigmentosus. This disorder should be considered in the differential diagnosis of macular hyperpigmentation, especially in those from more commonly affected ethnic and racial groups, even when the distribution is atypical and in the absence of history of sun exposure.

Mycobacterium haemophilum infection in a renal transplant patient with inflammatory bowel disease.

A 61-year-old immunosuppressed renal transplant patient with inflammatory bowel disease presented with tender pink nodules on the trunk and extremities. An initial biopsy was suggestive of metastatic Crohn disease, but after disease persistence, a second biopsy revealed disseminated Mycobacterium haemophilum. Atypical mycobacterial infections should be considered in immunosuppressed patients. This case highlights the complexities of diagnosing such infections in patients with an underlying granulomatous condition and the particular growth requirements of M. haemophilum.

Multifocal cutaneous alternariosis in a 70-year-old Kenyan renal transplant patient.

Alternaria species are a group of dematiaceous fungi that are ubiquitous in nature and are becoming an increasingly important cause of disease in immunocompromised patients. We present a case of a 70 year old renal transplant recipient with multiple areas of cutaneous Alternaria infections likely introduced during local trauma. Treatment has required a combination of systemic therapy and surgical excision. This case illustrates the importance of recognizing fungal infections with cutaneous manifestations, such as alternariosis, in immunosuppressed patients.

A case of Hansen Disease presenting as tinea versicolor.

Hansen Disease (leprosy) is an infectious disease that targets macrophages and Schwann cells, caused by the acid fast intracellular organism, Mycobacterium leprae. Clinically, it presents with a spectrum of findings that may include hypopigmented macules, erythematous plaques and nodules, and thickened or tender peripheral nerves. The most feared complication is mutilating damage to facial structures or digits resulting from loss of sensation in affected skin. In non-endemic areas, the diagnosis of leprosy is frequently delayed because it may mimic other more common skin conditions. We present a case of borderline/lepromatous leprosy in an otherwise healthy young Brazilian man that was initially diagnosed as tinea versicolor, but did not respond to appropriate treatment. This case highlights the importance of having a high index of suspicion for leprosy in patients from endemic areas who present with lesions that could be consistent with this disease.