Faculty Bibliography

We report a 46-year-old woman with a nine-year history of obesity; chronic diffuse pain in the adipose tissue of her medial upper arms, lower trunk, and thighs; multiple biopsy-proven lipomas and angiolipomas; and a lipomatous pseudomass of the breast. Her systemic symptoms included generalized weakness, fatigue, memory impairment, and arthralgias. Although some of the lesions were tender, most were only appreciated with palpation. Her clinical history and histopathologic data suggested adiposis dolorosa (Dercum's disease). Owing to the chronic pain, an interdisciplinary approach with the use of analgesics and doxycycline has been initiated.

We present a 64-year-old man with a three-year history of pruritic, pink papules and nodules of the face who was found to have a clonal lymphoproliferative B-cell disease that was characterized by a clonal IGH rearrangement. Although morphologic features present in the biopsy specimen were consistent with a reactive process, additional clinicopathologic correlation (anatomic presentation of lesions on the face, the absence of t(14:18) translocation, and bcl-2 and MUM1 expression) reinforced suspicion of a cutaneous B-cell lymphoma. Systemic work-up with CT/PET and a bone marrow biopsy ultimately excluded systemic disease and primary cutaneous follicle-center lymphoma (PCFCL) was a strong diagnostic consideration. The patient was treated with systemic rituximab with a partial resolution of the facial lesions. The case demonstrates both clinical and pathologic challenges to the diagnosis of primary cutaneous B-cell lymphoma (PCBCL). Furthermore, despite a newly refined classification system, the case also specifically highlights the persistent requirement for flexible clinical reasoning and pathologic correlation. Such reasoning is necessary to generate individualized strategies for diagnosis and treatment when cutaneous B-cell lymphoma is suspected.

Indeterminate cell histiocytosis (ICH) is a rare, heterogeneous disorder that is characterized by immunophenotypic features of both Langerhans cell histiocytosis (LCH) and non-LCH. We describe a 12-month-old boy with a four-month history of asymptomatic, small, pink-tan papules on his face. Histopathologic evaluation showed a superficial, dermal infiltrate of histiocytes that was positive for S100, CD1a, CD68, and Factor XIIIa. To our knowledge, this represents the first report of the clinical presentation of benign cephalic histiocytosis with immunohistochemical findings of ICH. We review the classification of histiocytic disorders and the clinical and immunohistochemical features of both ICH and benign cephalic histiocytosis.

A 24-year-old Bangladeshi man presented with a 12-week history of a pruritic papule on his left elbow that had enlarged and ulcerated. He was without any constitutional or systemic symptoms. He reported a history of extensive travel in the two years prior to presentation that included Bangladesh, South and Central America, and Mexico. Histopathologic features were consistent with leishmaniasis. Speciation by the Centers for Disease Control showed L. brasiliensis.

Osteoma cutis is the aberrant development of bone within the skin. The bone formation may be de novo (primary) or result from an injury to the skin (secondary). Here we present a healthy 53-year-old man with no known abnormalities in calcium or phosphate metabolism with plate-like osteoma cutis of the scalp. Plate- or plaque-like osteoma cutis was initially described as a congenital condition but has now been reported several times in the literature as an idiopathic process that occurs in adults. Treatment options are limited and are only required if the lesion is bothersome to the patient.

We present a case of exogenous ochronosis in a 53-year-old woman with skin type IV, who used a topical hydroquinone preparation of an unknown concentration for several years. Traditionally, exogenous ochronosis was thought to occur exclusively in patients with darker skin types who use high concentrations of hydroquinone cream. Reports now document cases in patients of all skin types and in patients even using low concentrations of hydroquinone cream for short periods of time. Although the incidence of exogenous ochronosis in the United States is unclear, it may be more common than many clinicians believe. It is important for clinicians and patients to be aware of exogenous ochronosis in order to prevent exacerbation in patients with this rare side effect.

Netherton syndrome is a rare, autosomal recessive disorder that is characterized by congenital ichthyosis, trichorrhexis invaginata, and atopic diathesis. Ichthyosis presents at birth with erythroderma and subsequently evolves into ichthyosis linearis circumflexa; hair shaft abnormalities tend to present later. The disorder is caused by loss-of-function mutations in the SPINK5 (serine protease inhibitor Kazal-type 5) gene that encodes LEKTI (lympho-epithelial Kazal-type related inhibitor), which is a protease inhibitor that counteracts epidermal proteases involved in desquamation. Use of topical medications is limited by potential for systemic absorption and toxicity in the setting of a defective skin barrier. Therapeutic options include topical glucocorticoids and retinoids, oral retinoids, and narrowband ultraviolet B phototherapy. Topical tacrolimus has been shown to be efficacious and may be used safely with careful laboratory monitoring.

A 26-year-old man presented with an 18-month history of a subcutaneous mass on his forehead that occurred shortly after being struck by a blunt object. Histopathologic examination showed a proliferation of bland spindle cells and a collagenous stroma that was consistent with cranial fasciitis. Cranial fasciitis, which is a variant of nodular fasciitis, is a benign fibroblastic neoplasm that overlies the skull and often is associated with trauma. Although its rapid onset may give the clinical impression of a malignant condition, cranial fasciitis typically is cured by simple excision without further sequelae.

Nevus lipomatosus superficialis is an uncommon cutaneous hamartoma that is characterized by the presence of adipose tissue within the reticular dermis. We describe a 15-year-old boy with a three-year history of the classic type of nevus lipomatosus superficialis, which presented as linear arrays of soft, cerebriform papulonodules and plaques in the right inguinal fold. Investigation for chromosomal aberrations and dysregulation of Wnt signaling may provide insights into the pathogenesis of this hamartoma. Treatment is usually with surgical excision although successful use of other modalities has been described.

Candida parapsilosis is an emerging fungal pathogen that was once thought to be solely a colonizing organism. C. parapsilosis is increasingly becoming reported as the most common Candida species that causes onychomycosis. Clinical findings include typically severe dystrophy of the nail fold and plate as well as thickening and fragmentation of the plate, particularly in the distal plate. We present a unique case of C. parapsilosis infection of the nail bed without infection of the nail plate and with twenty-nail melanonychia.