Richter Syndrome Presenting as Subcutaneous Nodules and a Dermal Plaque.

ABSTRACT: Richter syndrome (RS) describes a phenomenon in which a patient with chronic lymphocytic leukemia (CLL) develops an aggressive lymphoma, most commonly diffuse large B-cell lymphoma (DLBCL). Reports of cutaneous RS remain exceedingly rare. We report a 61-year-old woman with relapsed/refractory CLL presenting with several subcutaneous nodules on her arms and legs and a single dermal plaque on her abdomen. Skin biopsy revealed a diagnosis of DLBCL, ABC-type, and her clinical status rapidly deteriorated following diagnosis. We review the variety of clinical presentations of cutaneous RS, its association with CLL, risk factors for RS development in CLL patients, and the distinctive histopathologic and immunophenotypic features of DLBCL. We hope to highlight the importance of prompt skin biopsy in patients with CLL presenting with progressive skin lesions and increase awareness of this aggressive clinical syndrome.

Eosinophilic Fasciitis Possibly Provoked by Exercise.

A 26-year-old woman was referred to dermatology for evaluation of "lumpy skin" for 4 months. She experienced Achilles tendon pain and muscle tightness, occurring before the skin lesions had appeared. The lesions began on her arms and progressed to her legs over 1 month.

Useful cytological confirmation of HPV 13 in lesional mucosa enhances diagnosis of focal epithelial hyperplasia.

An 11-year-old female presented with multiple oral lesions for several months. Histopathological findings suggested focal epithelial hyperplasia (FEH), also known as Heck disease. FEH is strongly associated with Human papillomavirus (HPV), especially genotypes 13 and 32. An oral swab of a mucosal lesion was subsequently obtained for cytology, immunohistochemistry and in situ hybridization. In addition, in situ hybridization and immunohistochemistry were also performed retrospectively on the biopsy specimen for correlation. The cytology specimen showed squamous cells with enlarged, slightly atypical nuclei and rare perinuclear halos. The histology findings included papillomatosis with acanthosis, mild nuclear atypia and focal perinuclear halos. The immunohistochemistry for the consensus HPV L1 capsid protein was found in both the cytology and biopsy specimens indicating that the lesion was HPV-related. High viral copy numbers of HPV 13 were detected by in situ hybridization in both the cytology and histology specimens. Although histologic features of FEH have been well characterized in the literature, to our knowledge, this is the first case to describe in FEH with adjunct immunohistochemistry and in situ hybridization results. Furthermore, these findings assisted in our diagnosis since the patient's clinical presentation was a diagnostic challenge with smooth dome-shaped papules instead of the typically described flat-topped verrucous lesions seen in FEH. In summary, our case reveals that there is a high concordance between the HPV 13 detection in the cytology and histology of FEH, and that performing cytology in addition to histology can be used to optimize diagnostic evaluation towards appropriate patient care.

Identification of a novel variant of FOXP3 resulting in severe immune dysregulation, polyendocrinopathy, enteropathy, X-linked syndrome highlights potential pitfalls of molecular testing.

Immune dysregulation, polyendocrinopathy, enteropathy, X-linked (IPEX) syndrome is a rare genetic disorder that typically presents in the first year of life with severe diarrhea, autoimmune endocrine disorder, and inflammatory dermatitis, most commonly an eczematous dermatitis. IPEX syndrome is caused by variants in the FOXP3 gene leading to dysregulation of T-regulatory (Treg) cells and an aberrant immune response. Here, we present a case of severe IPEX syndrome diagnosed following whole genome sequencing (WGS) in a 2-week-old boy with bloody mucoid diarrhea, failure to thrive, and a diffuse eczematous dermatitis. As multiple variants of interest were identified with WGS, this case highlights the importance of relating the clinical symptoms to the genetic results.

Langerhans cell histiocytosis: A great imitator.

Langerhans cell histiocytosis (LCH) is an uncommon but serious inflammatory neoplasia that affects many organs, including the skin. Though uncommon, it should remain high on a clinician's differential diagnosis in treatment-resistant cases of conditions, such as seborrheic dermatitis, diaper dermatitis, arthropod bites, and many more. A thorough history nd physical examination for each patient can aid in the diagnosis; however, if clinically suspicious for LCH, a punch biopsy should be performed. Histologic evaluation of LCH is often enough to differentiate it from the many clinical mimickers. Characteristic findings include a histiocytic infiltrate with "coffee bean"-cleaved nuclei, rounded shape, and eosinophilic cytoplasm. Immunohistochemical stains, including CD1a, S100, and CD207 (langerin) are often needed for a definitive diagnosis. Electron microscopy also demonstrates the ultrastructural presence of Birbeck granules, but this is no longer needed due to immunohistochemical staining. Treatment is often necessary for LCH, if systemic involvement exists.

Treatment of warts with topical cidofovir in a pediatric patient.

Cidofovir is an antiviral nucleotide analogue with relatively new treatment capacities for dermatological conditions, specifically verruca vulgaris caused by human papilloma virus infection. In a 10-year old boy with severe verruca vulgaris recalcitrant to multiple therapies, topical 1% cidofovir applied daily for eight weeks proved to be an effective treatment with no adverse side effects. This case report, in conjunction with multiple published reports, suggests that topical 1% cidofovir is a safe and effective treatment for viral warts in pediatric patients.

The color of skin: orange diseases of the skin, nails, and mucosa.

Cutaneous disease can present with lesions of all colors of the visible spectrum. Lesions of the skin, nail, and mucous membranes with an orange color can be due to a variety of etiologies. The conditions may appear as purely orange, yellow-orange, red-orange, tan, or brown with an orange hue. The orange color may also present as a transient phase of a disease process. As with all dermatologic pathology, a key way to distinguish orange-colored lesions is by distribution and morphology. The sclera, palate, lips, gingiva, and nails may also be involved. A literature review using PubMed with keywords, including orange, skin, mucosa, cutaneous, xanthoderma, and granuloma, was conducted to gather all dermatologic conditions that can present with an orange color. The relevant diseases were categorized by etiology and include inflammatory, infectious, neoplastic, and exogenous causes.

Pediatric primary cutaneous blastomycosis clinically responsive to itraconazole.

Primary cutaneous blastomycosis is a rare infection, especially among children. We present the case of a 16-year-old immunocompetent adolescent boy with primary cutaneous blastomycosis arising after falling into a flowerbed in a region where the fungus Blastomyces dermatitidis is hyperendemic. Following treatment with itraconazole 200 mg 3 times daily for 3 days, followed by 200 mg 2 times daily for 6 months, the lesion healed with only residual dyschromia.

Eruptive vellus hair cysts in identical triplets with dermoscopic findings.

Eruptive vellus hair cysts (EVHCs) are asymptomatic, follicular, flesh-colored to hyperpigmented papules that are typically located on the chest and extremities with an unclear inheritance pattern and pathogenesis. We report a case of EVHCs in 4-year-old identical triplet girls. Our aim is to present another rare case of autosomal-dominant inheritance of EVHCs and to emphasize the utility of dermoscopy as a diagnostic aid for EVHCs that may be misdiagnosed clinically.

Pallister-Killian syndrome in a two-year-old boy.

Pallister-Killian syndrome (PKS) is a rare, sporadic, multisystem developmental disorder characterized by craniofacial dysmorphic features. We report a case of a two-year-old boy with PKS to highlight the cutaneous findings and emphasize the importance of diagnostic skin biopsies in patients with cutaneous pigmentation changes and distinctive facial features.

Acne isolated within a Becker nevus of a 14 year-old girl.

Becker nevus (BN) is a common benign condition occurring most often in young men, much more often than in women. Acne isolated within a BN is a rare phenomenon hypothesized to occur, at least in part, due to increased androgen sensitivity within the nevus. We present a rare case of papular acne with in a BN of a 14 year-old girl.

A perforating pilomatricomal horn on the arm of an 11-year-old girl.

Cutaneous horns are uncommon in adults and rare in the pediatric population. Although verruca vulgaris, solar keratosis, and squamous cell carcinoma are more common entities that can present as cutaneous horns in the general population, conditions such as molluscum contagiosum, juvenile xanthgranuloma, and pyogenic granuloma have been reported causes in the pediatric population. We present a case of a perforating pilomatricoma presenting as a cutaneous horn in an 11 year old girl.