Presentations of Cutaneous Disease in Various Skin Pigmentations: Acne Vulgaris - Comedonal Acne.

Description Acne vulgaris is a common inflammatory skin condition of the pilosebaceous unit in adolescents and young adults and is primarily characterized by the presence of open and closed comedones. In patients of various skin pigmentations, skin-colored comedones may be difficult to appreciate and lead to incorrect or delayed diagnosis of acne. To aid in the identification of acne vulgaris in patients of various skin pigmentations, we present comedonal acne in different skin types and commonly encountered differential diagnoses. With its significant volume and burden of disease, acne vulgaris should be correctly identified in various skin pigmentations by primary care clinicians for the initiation of appropriate management.

Resolved Peristomal Erosive Papulonodular Dermatitis Mimicking Nevoid Hyperkeratosis of the Nipple and Areola.

Introduction: Nevoid hyperkeratosis of the nipple and areola (NHKNA) is a rare cutaneous entity with a distinct clinical and histological presentation. The type II form of this condition can result from various dermatoses, such as irritant contact dermatitis. Erosive papulonodular dermatitis is a chronic irritant dermatitis that often occurs in areas of occlusion and maceration, such as peristomal skin. Pseudoverrucous papules and nodules are a variant of erosive papulonodular dermatitis and have a non-specific histologic pattern of reactive hyperplasia. Case Presentation: We present a case of a patient with resolved peristomal erosive papulonodular dermatitis who presented status-post ileostomy reversal with clinical and histologic findings classically seen in NHKNA. Conclusion: In type II NHKNA, treatment of the primary dermatosis typically leads to resolutions. In the case of our patient, removal of the offending agent via colostomy reversal and barrier protection led to the resolution of the lesions.

Presentations of Cutaneous Disease in Various Skin Pigmentations: Inverse Psoriasis.

Description Inverse psoriasis is a clinical variant of psoriasis involving flexural or intertriginous areas of the body. Inverse psoriasis may be present in 3 to 36% of psoriasis patients. Lesions are clinically characterized as smooth, well-demarcated, erythematous plaques (raised, >1 cm) without the typical silvery scales of classic psoriasis. Differential diagnosis includes tinea infection, candidiasis, seborrheic dermatitis, or bacterial streptococcal infection. The clinical images in this review focus on identifying inverse psoriasis along the full spectrum of skin tones.

Presentations of Cutaneous Disease in Various Skin Pigmentations: Cutaneous Abscesses.

Description Cutaneous abscesses are collections of pus resulting from skin and soft tissue bacterial infections. They clinically exhibit the four cardinal inflammatory signs of pain, warmth, swelling, and erythema. In patients with darkly pigmented skin, classically-associated erythema may be challenging to appreciate and can lead to missed or delayed diagnosis. We compare abscess presentations in different skin types. Recognition of varying presentations of cutaneous abscesses in diverse skin colors will help clinicians utilize additional clues to identify and diagnose this entity correctly.

Delayed Diagnosis of Klippel-Trénaunay Syndrome in a 23-year-old African American Male.

Description Klippel-Trénaunay syndrome is a rare genetic disorder that typically presents as a triad of symptoms consisting of venous malformations (varicosities), capillary malformations (port-wine stain), and limb overgrowth. We followed a 23-year-old African American male with a past medical history of peripheral vascular disease, who was visiting the dermatology clinic for a persistent skin lesion on his thigh. During physical examinations, we noted a subtle port-wine stain on his right leg, right leg hypertrophy, and peripheral vascular disease. Skin findings were difficult to observe on his darker skin tone, Fitzpatrick skin type VI, which may have led to the delayed diagnosis of Klippel-Trénaunay syndrome. The lesion of concern was removed during a follow-up visit and was consistent with an angiokeratoma. Our patient had not suffered any serious complications from his new diagnosis of Klippel-Trénaunay syndrome; however, there was a concern for thrombotic events.

Presentations of Cutaneous Disease in Various Skin Pigmentations: Plaque Psoriasis.

Description Recent studies estimate that more than 8 million Americans have psoriasis. The prevalence of psoriasis in African Americans is 1.5% compared to 3.6% of Caucasians. Psoriasis is likely to be underdiagnosed among African Americans and other individuals with darker pigmented skin due to variations in clinical presentation in addition to disease distribution and severity. We present images of psoriasis vulgaris in a variety of Fitzpatrick skin types. Differences in the biology of skin pigmentation may explain the clinical masking of erythema in darker-skinned individuals. Recognition of this important difference will help clinicians utilize additional clues to identify and diagnose this entity correctly.

Pleomorphic Dermal Sarcoma: A Clinical and Histopathologic Emulator of Atypical Fibroxanthoma, but Different Biologic Behavior.

Description Pleomorphic dermal sarcoma (PDS) can clinically and histopathologically mimic atypical fibroxanthoma (AFX). However, it has a more aggressive clinical course with a higher recurrence rate and metastatic potential. This case presentation aims to report a rapidly-growing, exophytic, 4 cm tumor following a non-diagnostic shave biopsy 2 months prior and to highlight distinctive features between PDS and AFX needed to make the correct diagnosis. Like AFX, PDS occurs on the sun-damaged skin of the elderly, usually on the head and neck. Also, like AFX, PDS histopathologically consists of sheets or fascicles of epithelioid and/or spindle-shaped cells, often with multinucleation, pleomorphism, and numerous mitotic figures. Immunohistochemistry cannot distinguish PDS from AFX but is used to exclude other malignancies. PDS can be distinguished from AFX by size (PDS is usually >2.0 cm) and by the presence of more aggressive histopathologic features, such as subcutaneous involvement, perineural and/or lymphovascular invasion, and necrosis. PDS is a rare entity not well documented in the literature with confusing, misleading, and changing nomenclature. PDS is a diagnosis of exclusion made after complete excision of the tumor with the aid of histopathology and immunohistochemistry.

Linear Cutaneous Lupus Erythematosus Following Blaschko's Lines on the Scalp: Additional Cases and Review of the Literature.

Description Alopecia of the scalp has various causes and presentations. However, linear alopecia is unusual and lupus erythematosus presenting as linear alopecia is exceedingly rare. To date, there have been 16 documented cases of linear alopecia diagnosed as chronic cutaneous lupus erythematosus occurring in a linear configuration following Blaschko's lines. We report 2 additional cases and review the clinical and histologic features along with treatment. This Blaschkoid linear variant of cutaneous lupus erythematosus has distinct clinical and histologic characteristics that set it apart from other causes of alopecia and from classic forms of cutaneous lupus. These distinct features include a linear configuration, a younger age of presentation, a disproportionate number of Asians affected, and a paucity of cases with systemic involvement. Histologically, the lesions are characterized by prominent mucin in the dermis and subcutaneous tissues. Blaschkoid linear lupus of the scalp is sufficiently distinctive to suggest the diagnosis on histology alone, in the appropriate clinical context. The most common and successful treatments included systemic and/or combination treatment with oral hydroxychloroquine, oral steroids, and/or intralesional steroids.

Congenital Giant Juvenile Xanthogranuloma, Let It Be.

Description Juvenile xanthogranuloma (JXG) is a rare type of non-Langerhans cell histiocytosis. JXGs are benign and have a self-limiting course generally lasting 6 months to 3 years, with some reported durations longer than 6 years. We present a rarer congenital giant variant, defined as lesions with a diameter larger than 2 cm. It is uncertain if the natural history of giant xanthogranulomas is similar to the usual JXG. We followed a 5-month-old patient with a 3.5 cm in diameter, histopathologically-confirmed, congenital, giant JXG located on the right side of her upper back. The patient was seen every 6 months for 2.5 years. At 1 year of age, the lesion had decreased in size, lightened in color, and was less firm. At 1.5 years old, the lesion had flattened. By 3 years old, the lesion had resolved but left a hyperpigmented patch with a scar at the punch biopsy site. Our case represents a congenital giant JXG that was biopsied to confirm the diagnosis and then monitored until resolution. This case supports the clinical course of giant JXG not being affected by the larger lesion size and that aggressive treatments or procedures are not warranted.

Cutaneous leishmaniasis in a 65-year-old North Texas male, treated with cryotherapy: A case report.

We report a case of a 65-year-old male seen in a North Texas dermatology clinic with three erythematous nodules possessing central ulceration and scaling on the left lateral shoulder, present for months. Head, ears, lips, oral mucosa, and other body surfaces did not reveal similar lesions, and review of systems was negative. Shave biopsy was performed and histopathological findings demonstrated granulomatous inflammation in the dermis and parasitized histiocytes containing peripherally located amastigotes. Leishmaniasis was diagnosed and patient was educated on the disease while communication with the Centers for Disease Control and Prevention was initiated. The patient declined systemic medications from infectious disease specialists and, 3 weeks later, returned for follow-up treatment with cryotherapy.

Local manganese chloride treatment accelerates fracture healing in a rat model.

This study investigated the effects of local delivery of manganese chloride (MnCl2), an insulin-mimetic compound, upon fracture healing using a rat femoral fracture model. Mechanical testing, histomorphometry, and immunohistochemistry were performed to assess early and late parameters of fracture healing. At 4 weeks post-fracture, maximum torque to failure was 70% higher (P<0.05) and maximum torsional rigidity increased 133% (P<0.05) in animals treated with 0.125 mg/kg MnCl2 compared to saline controls. Histological analysis of the fracture callus revealed percent new mineralized tissue was 17% higher (P<0.05) at day 10. Immunohistochemical analysis of the 0.125 mg/kg MnCl2 treated group, compared to saline controls, showed a 379% increase in the density of VEGF-C+ cells. In addition, compared to saline controls, the 0.125 mg/kg MnCl2 treated group showed a 233% and 150% increase in blood vessel density in the subperiosteal region at day 10 post-fracture as assessed by detection of PECAM and smooth muscle α actin, respectively. The results suggest that local MnCl2 treatment accelerates fracture healing by increasing mechanical parameters via a potential mechanism of amplified early angiogenesis leading to increased osteogenesis. Therefore, local administration of MnCl2 is a potential therapeutic adjunct for fracture healing.

Dissociable connectivity within human angular gyrus and intraparietal sulcus: evidence from functional and structural connectivity.

The inferior parietal lobule (IPL) of the human brain is a heterogeneous region involved in visuospatial attention, memory, and mathematical cognition. Detailed description of connectivity profiles of subdivisions within the IPL is critical for accurate interpretation of functional neuroimaging studies involving this region. We separately examined functional and structural connectivity of the angular gyrus (AG) and the intraparietal sulcus (IPS) using probabilistic cytoarchitectonic maps. Regions-of-interest (ROIs) included anterior and posterior AG subregions (PGa, PGp) and 3 IPS subregions (hIP2, hIP1, and hIP3). Resting-state functional connectivity analyses showed that PGa was more strongly linked to basal ganglia, ventral premotor areas, and ventrolateral prefrontal cortex, while PGp was more strongly connected with ventromedial prefrontal cortex, posterior cingulate, and hippocampus-regions comprising the default mode network. The anterior-most IPS ROIs, hIP2 and hIP1, were linked with ventral premotor and middle frontal gyrus, while the posterior-most IPS ROI, hIP3, showed connectivity with extrastriate visual areas. In addition, hIP1 was connected with the insula. Tractography using diffusion tensor imaging revealed structural connectivity between most of these functionally connected regions. Our findings provide evidence for functional heterogeneity of cytoarchitectonically defined subdivisions within IPL and offer a novel framework for synthesis and interpretation of the task-related activations and deactivations involving the IPL during cognition.