Histopathologic reaction patterns to differentially cross-linked hyaluronic acid fillers: A retrospective case series.

BACKGROUND: Hyaluronic acid filler reactions have been increasingly observed in recent years. Our study investigates whether the increased number of filler reactions observed since 2014 is associated with a specific histopathologic inflammatory pattern and type of filler. METHODS: The institution's dermatopathology electronic database was retrospectively searched for histopathologic reactions to hyaluronic acid from January 2014 to December 2019. The age, sex, type of filler, procedure, location, and histopathologic patterns were recorded. RESULTS: From 2014 to 2019, there were 15 cases of granulomatous reactions to hyaluronic acid filler. In 10 of these cases, there was a characteristic inflammatory pattern characterized by tightly cuffed palisades of histiocytes with varying numbers of eosinophils. Of the 11 cases in which the type of filler was known, all used Vycross technology, a novel manufacturing process in the production of hyaluronic acid filler. CONCLUSION: A characteristic histopathologic pattern of discrete foci of tightly cuffed palisaded granulomas with eosinophils is associated with fillers manufactured using Vycross technology.

Papillary Dermal Elastolysis Secondary to Combination Nivolumab and Cabiralizumab Therapy: Histiocytes and Dermal Mucin as Clues to the Diagnosis.

ABSTRACT: Papillary dermal elastolysis has been described in the setting of experimental combination nivolumab and cabiralizumab immunotherapy. We report a third patient with distinctive, generalized atrophic macules that developed after a morbilliform eruption during a clinical trial for treatment of metastatic pancreatic adenocarcinoma. Histopathological findings demonstrated diminished elastic fibers in the papillary dermis, associated with a histiocyte-rich infiltrate and increased dermal mucin, features that should clue the dermatopathologist to this condition.

Henoch-Schönlein purpura and crohn's disease: Expanding the range of association in pediatric patients.

The association of new onset Henoch-Schönlein purpura (HSP) and inflammatory bowel disease (IBD) has been reported in the setting of concomitant anti-TNF-ɑ treatment. We present two pediatric IBD cases who developed new onset HSP without such association. These cases add to the literature by suggesting an association between HSP and IBD in pediatric population. We discuss possible underlying pathophysiological mechanisms, suggesting some commonality with IgA nephropathy. Increased awareness for HSP in pediatric IBD patients regardless of anti-TNF- ɑ therapy involvement is important for timely recognition and appropriate multi-disciplinary management.

Desmoplastic Melanoma Masquerading as Neurofibroma.

Desmoplastic melanoma (DMM) is a rare variant of melanoma that presents major diagnostic challenges. It can mimic both benign or other malignant tumors and may be easily confused by clinicians and pathologists. We report a patient who presented with a pink-colored papule on the left lateral neck. Histopathology revealed a nodular spindle cell tumor in the dermis resembling a neurofibroma at low power. However, higher-power evaluation and the use of immunohistochemical staining confirmed the diagnosis of DMM.We present this case to highlight the ongoing challenges of diagnosing DMM both clinically and histologically and to review the salient features of this often benign-appearing tumor. Advancing age, male gender, and head and neck location are associated with an increased risk of DMM-specific death. It is important that new or changing lesions in the correct cohort and location are biopsied promptly.