Diagnostic delay, comorbid hidradenitis suppurativa and the prognostic value of bacterial culture in folliculitis decalvans: A cohort study.

Background: Folliculitis decalvans (FD) is a type of primary neutrophilic cicatricial alopecia often leading to irreversible hair loss. Data on its epidemiology, clinical features, outcomes, and prognostic factors are limited.

Objective: To evaluate a cohort of patients with FD and identify characteristics of severe disease and prognostic factors which impede remission.

Assessment of a Diagnostic Classification System for Management of Lesions to Exclude Melanoma.

Importance: The proposed MOLEM (Management of Lesion to Exclude Melanoma) schema is more clinically relevant than Melanocytic Pathology Assessment Tool and Hierarchy for Diagnosis (MATH-Dx) for the management classification of melanocytic and nonmelanocytic lesions excised to exclude melanoma. A more standardized way of establishing diagnostic criteria will be crucial in the training of artificial intelligence (AI) algorithms.

Objective: To examine pathologists' variability, reliability, and confidence in reporting melanocytic and nonmelanocytic lesions excised to exclude melanoma using the MOLEM schema in a population of higher-risk patients.

Histologic Patterns and Clues to Autoinflammatory Diseases in Children: What a Cutaneous Biopsy Can Tell Us.

Autoinflammation is defined by aberrant, antigen-independent activation of the innate immune signaling pathways. This leads to increased, pro-inflammatory cytokine expression and subsequent inflammation. In contrast, autoimmune and allergic diseases are antigen-directed immune responses from activation of the adaptive immune system.

Clinicopathologic and immunophenotypic characterization of lichen planopilaris and central centrifugal cicatricial alopecia: A comparative study of 51 cases.

Background: The purpose of the study was to compare the histopathologic and immunophenotypic features of central centrifugal cicatricial alopecia (CCCA) and lichen planopilaris (LPP) to better characterize and differentiate these two clinical entities. CCCA remains an ill-defined and still-unsettled histologic entity and many hair loss experts regard CCCA to be histologically indistinguishable from LPP. Given the overlapping histologic features of these two lymphocyte-predominant cicatricial alopecias, and the lack of consensus regarding the significance of proposed distinctions, dermatopathologists face difficulty in providing clinicians and patients certainty with a definitive diagnosis of CCCA vs LPP.

Immunohistochemical characterization of benign activation of junctional melanocytes and melanoma in situ of the nail unit.

Background: Immunohistochemical (IHC) stains that distinguish benign, pigmented nail lesions from malignancy are needed. Candidate markers of malignant transformation include p16, HMB45, and Ki-67, with p16 being of particular interest. There is limited knowledge about the spectrum of p16 expression in pigmented lesions, especially junctional melanocytic proliferations of the nail.

Longitudinal Melanonychia Biopsy: What Not to Do.

The nail matrix biopsy is an important technique in confirming or excluding a diagnosis of melanoma in a patient with longitudinal melanonychia. Dermatologists are the first-line diagnosticians for these pigmented lesions of the nail unit, however, for different reasons, some are reluctant to perform a nail biopsy. This case demonstrates how a poor biopsy technique resulted in a misdiagnosis in a patient with melanoma in situ.

How to submit a nail specimen.

The scarcity of specific submission protocols for nail unit biopsies presents many challenges for appropriate specimen processing. Many nail biopsies are received fragmented or without orientation, often resulting in less-than-ideal tissue embedding and poor histologic sections, which are difficult to interpret. Methods are described for proper nail matrix/bed biopsy and plate submission that incorporate aspects of previous submission protocols and include inking the biopsy specimen along with submitting the tissue on a drawing of the nail.

Absence of catagen/telogen phase and loss of cytokeratin 15 expression in hair follicles in lichen planopilaris.

Background: Lichen planopilaris (LPP) is a lymphocyte-mediated cicatricial alopecia mostly involving the bulge region of the hair follicle. The origin of LPP is unknown. Therapy for LPP often does not prevent disease progression.

Erysipelas-like erythema of familial Mediterranean fever syndrome: a case report with emphasis on histopathologic diagnostic clues.

We report histopathological findings in a case of familial Mediterranean fever (FMF) syndrome with an erysipelas-like erythema (ELE). ELE is the only pathognomic cutaneous manifestation of FMF. ELE is characterized by well-demarcated, tender, erythematous and infiltrated plaques recurring on the same site and resolving spontaneously within 48-72 h.