Round Bodies Detected by Treponema pallidum Immunohistochemical Stain in Two Cases of Cutaneous Syphilitic Gummata.

ABSTRACT: Tertiary syphilis may present a diagnostic challenge due to negative nontreponemal serologies in up to 30% of cases and frequent lack of identifiable spirochetes on histopathology or other direct detection tests. We report 2 cases of round bodies staining with Treponema pallidum immunohistochemistry by light microscopy in biopsies from cutaneous syphilitic gummata. In 1 case, the finding was validated 3 times by 2 independent laboratories; in the other case, T. pallidum was detected by polymerase chain reaction in the biopsy sample. Spirochete round bodies have previously been reported in the setting of electron microscopy and fluorography, but to the best of our knowledge, have not been reported by light microscopy in a routine skin biopsy. Although the clinical implications are unclear, this may represent a helpful new paradigm for the diagnosis of tertiary syphilis.

A case of eruptive lichen spinulosus after toxic epidermal necrolysis.

We report a case of a 13-year-old boy who presented with eruptive monomorphic white papules on the trunk and arms involving regions previously affected by toxic epidermal necrolysis (TEN). Biopsy revealed compact keratin involving the hair follicle and sparse mixed perivascular infiltrate, findings consistent with lichen spinulosus. Improvement was noted after treatment with ammonium lactate 12% lotion. While cutaneous dyschromia and xerosis are common after TEN, lichen spinulosus has not yet been described in the literature. It is important for providers to be aware of any potential cutaneous sequelae of TEN that can affect quality of life in order to best counsel their patients.

Erythromelalgia successfully treated with low-dose gabapentin in a pediatric patient.

Primary erythromelalgia, while uncommon, may significantly decrease the quality of life of those affected. While many patients with erythromelalgia require systemic therapy, there is no standard of care for this condition. Herein, we report a 7-year-old girl who experienced resolution of erythromelalgia symptoms with no adverse effects after treatment with low-dose gabapentin. We also discuss the safety and efficacy of low-dose gabapentin in children for treatment of pain.

Intravenous Lobular Capillary Hemangioma: A Case Report and Proposal for New Cutaneous Tender Tumor Differential Diagnosis Acronym.

Here, we report a case of a 70-year-old female who presented with a slowly enlarging tender nodule on the right forearm for several months. Physical examination showed a faintly blue-tinged freely mobile subcutaneous nodule. Excision was complicated by greater than expected bleeding and revealed an unexpected intravenous mass. Histopathology demonstrated capillary lobules separated by fibrous septae within a vein, consistent with intravenous lobular capillary hemangioma (IVLCH). IVLCH is a rare benign capillary proliferation of unclear etiology. Excision is typically curative and relieves any pain and discomfort the patient might be experiencing. With the addition of IVLCH, we respectfully propose a new acronym for the differential diagnosis of cutaneous tender tumors: intravenous lobular capillary hemangioma, foreign body (reaction), hidradenoma, osteoma cutis, glomus tumor, scar, fibromyxoma, leiomyosarcoma, eccrine angiomatous hamartoma, Dercum's disease (adiposis dolorosa), piezogenic pedal papule, eccrine spiradenoma, neurilemmoma (schwannoma), calcinosis cutis, angioendotheliomatosis, leiomyoma, metastases, angiolipoma, neuroma, dermatofibroma, granular cell tumor, endometriosis, thrombus, blue rubber bleb nevus, angioma, chondrodermatitis nodularis helicis, and keloid ("IF HOGS FLED PEN, CALM AND GET BACK"). Future additions to the cutaneous tender tumor differential diagnosis may require creative additions and rearrangements to this acronym. However, continual updates will allow it to serve both clinicians and pathologists alike as a comprehensive representation of etiologies to consider for cutaneous tender tumors.

Enfortumab Vedotin-Associated Toxic Epidermal Necrolysis-like Toxic Erythema of Chemotherapy.

ABSTRACT: Enfortumab vedotin is an antibody-drug conjugate used for treatment of urothelial cancer. It has recently been associated with several reports of Stevens Johnson syndrome/toxic epidermal necrolysis (TEN). In this report, we describe the case of a 63-year-old man who developed widespread, near full-thickness desquamation, clinically mimicking TEN but with histologic features of toxic erythema of chemotherapy. This distinction is significant because it may have implications for prognosis and treatment. Further investigation is needed to ascertain the incidence of true TEN versus clinical imitators in patients with enfortumab vedotin-related cutaneous toxicity.