Search

Lupus erythematosus (LE)-specific bullous lesions are often difficult to distinguish from other bullous diseases presenting in patients with systemic lupus erythematosus. Herein, we describe a 49-year-old woman with systemic lupus erythematosus with recurrent tense bullae on the forearms. Clinical, histopathologic, and serologic findings led to the diagnosis of LE-specific bullous lesions. We also summarize the diagnostic clues for distinguishing LE-specific bullous lesions, bullous systemic lupus erythematosus, and erythema multiforme-like lesions in LE (Rowell syndrome).

Lymphomatoid papulosis is a chronic CD30-positive cutaneous lymphoproliferative disorder that is characterized by recurring red-brown necrotic papules. It exhibits a wide spectrum of histopathologic findings and is often associated with cutaneous T-cell lymphomas. Six different histological subtypes have been classified by the WHO, but there is limited understanding regarding rare histopathologic variants. We describe a 51-year-old man who presented with recurring, necrotic papules for 6 years that progressed to involve the face, scalp, trunk, axilla, and scrotum. Histopathology demonstrated sarcoidal granulomas, along with a CD30-positive T cell infiltrate which demonstrated clonality by T cell receptor gamma gene rearrangement. A diagnosis of lymphomatoid papulosis associated with granulomas was established based on the clinical and histopathologic presentation. The clinical understanding of granulomatous lymphomatoid papulosis is limited in the available literature and more awareness of this histopathologic variant is required for accurate classification of this disorder.

BackgroundAppropriate use criteria (AUC) provide patient-centered physician guidance in test selection. An initial set of AUC was reported by the American Society of Dermatopathology (ASDP) in 2018. AUC reflect evidence collected at single timepoints and may be affected by evolving evidence and experience. The objective of this study was to update and expand AUC for selected tests.MethodsRAND/UCLA (RAND Corporation [Santa Monica, CA]/University of California Los Angeles) methodology used includes the following: (a) literature review; (b) review of previously rated tests and previously employed clinical scenarios; (c) selection of previously rated tests for new ratings; (d) development of new clinical scenarios; (e) selection of additional tests; (f) three rating rounds with feedback and group discussion after rounds 1 and 2.ResultsFor 220 clinical scenarios comprising lymphoproliferative (light chain clonality), melanocytic (comparative genomic hybridization, fluorescence in situ hybridization, reverse transcription polymerase chain reaction, telomerase reverse transcriptase promoter), vascular disorders (MYC), and inflammatory dermatoses (periodic acid-Schiff, Gömöri methenamine silver), consensus by panel raters was reached in 172 of 220 (78%) scenarios, with 103 of 148 (70%) rated "usually appropriate" or "rarely appropriate" and 45 of 148 (30%), "appropriateness uncertain."LimitationsThe study design only measures appropriateness. Cost, availability, test comparison, and additional clinical considerations are not measured. The possibility that the findings of this study may be influenced by the inherent biases of the dermatopathologists involved in the study cannot be excluded.ConclusionsAUC are reported for selected diagnostic tests in clinical scenarios that occur in dermatopathology practice. Adhering to AUC may reduce inappropriate test utilization and improve healthcare delivery.

Mucous membrane pemphigoid, formerly known as cicatricial pemphigoid, is a rare and difficult-to-treat bullous disorder that occurs most commonly in older adults. We describe a 32-year-old woman who was diagnosed with anti-laminin 332 mucous membrane pemphigoid through indirect immunofluorescence for laminin 332 following nonspecific histologic and direct immunofluorescence findings. At 16 weeks following completion of her first cycle of with rituximab 375mg/m2 weekly for four weeks, her mucosal erosions had resolved. Although not widely available, this case highlights the utility of anti-laminin 332 immunofluorescence for diagnostic confirmation of this entity and the efficacy of rituximab in obtaining disease control.

Knuckle pads are benign painless papules and nodules that most commonly appear on the extensor surfaces of the proximal interphalangeal joints. Knuckle pads are frequently misdiagnosed due to their location overlying joints, which can lead to costly interventions and patient discomfort for a relatively harmless condition. We describe a 44-year-old woman who presented with mildly painful nodules on multiple bilateral proximal interphalangeal joints. The patient did not have a family history of fibromatosis and the rheumatoid factor was negative. Histology showed mild epidermal hyperkeratosis, papillomatosis, and acanthosis with a deep dermal, poorly circumscribed, proliferative nodule made of spindled myofibroblasts without cytological atypia. The diagnosis of knuckle pads was established based on the clinical and morphological presentation of the nodules. Treatment with intralesional triamcinolone acetonide injection produced significant clinical improvement. Our findings highlight the challenging diagnosis of knuckle pads and the importance of increasing the familiarity of knuckle pads in modern medical practice.

Chimeric antigen receptor (CAR) T‐cell therapy has demonstrated remarkable success in treating various B‐cell malignancies, redirecting T‐cell cytotoxicity toward cancer cells. Despite its efficacy, CAR‐T therapy is associated with potential risks, including cytokine release syndrome (CRS) and cytopenia. We present a case of a 69‐year‐old man with diffuse large B‐cell lymphoma treated with axicabtagene‐ciloleucel CAR‐T therapy, who developed a rare and severe cutaneous toxicity resembling toxic epidermal necrolysis (TEN). The patient exhibited persistent fevers, CRS, and subsequent development of a widespread erythematous macular eruption, progressing to vesiculation with bullae. Notably, allopurinol‐induced TEN was considered with the patient's recent exposure to allopurinol, although the onset and minimal mucosal involvement did not align with typical presentations of allopurinol‐induced cases. The cutaneous reaction, distinct from typical SJS/TEN, showed minimal mucosal involvement and coincided with the cytokine release storm, differing from allopurinol‐induced TEN. Despite the absence of guidelines, the patient was managed with systemic steroids, achieving significant improvement. This case expands the spectrum of CAR‐T therapy‐related cutaneous toxicities, highlighting the need for early recognition of histopathology and tailored management by dermatologists. Further understanding of these reactions is crucial for optimizing the safety profile of this groundbreaking immunotherapy. [ABSTRACT FROM AUTHOR]

Enzyme-linked immunosorbent assay is a sensitive and specific method for the detection of circulating autoantibodies in pemphigus vulgaris and foliaceus. Herein, pemphigus erythematosus with equivocal immunofluorescence and non-diagnostic histology, but confirmed by enzyme-linked immunosorbent assay, is described. As a non-invasive, sensitive, and specific assay with additional utility for monitoring disease activity, this case adds to growing evidence supporting ELISA as the diagnostic method of choice for common and less common variants of pemphigus.

Rituximab and intravenous immunoglobulin [IVIg] have recently emerged as effective treatments for pemphigus refractory to corticosteroids [CS]. This case series sought to compare the clinical, serologic,and adverse effects of CS, IVIg, and rituximab in patients with pemphigus. A retrospective review of 63 patients with pemphigus vulgaris (PV), pemphigus foliaceus (PF), or paraneoplastic pemphigus (PNP)was performed. Clinical remission (CR), serologic remission (SR), and adverse effects were evaluated. Three study groups were compared: patients treated with systemic CS, refractory patients treated withIVIg, and refractory patients treated with rituximab. The overall number of adverse effects was not significantly different between the groups but those observed in patients treated with systemic CS weremore severe. CR was less likely in the patients treated with systemic CS than in patients treated with IVIg or rituximab, P-value = 0.000467. SR was more likely in patients treated with systemic CS or rituximab thanin patients treated with IVIg, P-value = 0.002118. These results suggest that the clinical efficacy of IVIg is not correlated with an expected concomitant SR. Frequently reserved for refractory pemphigus,IVIg and rituximab are significantly more likely to produce clinical remission than systemic CS therapy, suggesting their utility as first-line treatments.

Background: Due to perceived difficulty in the categorization of angioinvasive fungal infections based on histopathology, variation exists in dermatopathology reporting. Methods: This study characterized the diagnosis of angioinvasive fungal infections by light microscopy at a single academic institution over an 11‐year period. Subsequently, the accuracy of blinded reclassification by virtual microscopy was measured. Results: Seventy‐six specimens with hematoxylin–eosin slides were obtained from 33 patients. The mean diagnostic accuracy of dermatopathologists in differentiating mucormycosis, hyalohyphomycosis, and phaeohyphomycosis based on blinded reclassification via virtual microscopy was 74%, with a range of 65%–91%. Conclusions: While there was a range in diagnostic accuracy, the highest score of 91% and the identification of common sources of error suggest that histopathologic categorization of angioinvasive fungal infections can frequently be performed. However, accurate identification is not always possible given common pitfalls in diagnosis. In addition, standardized and clinically useful reporting should be considered. [ABSTRACT FROM AUTHOR]

Hidrocystomas are common, benign adnexal neoplasms most frequently found on the eyelids, canthi, or periocular areas. Herein, we report a case of multiple hidrocystomas distributed over less common facial areas: cheeks and cutaneous lips.