Rosacea Granulomatosis in a Neutropenic Leukemic Patient.

Rosacea granulomatosis is a common, chronic skin disorder that primarily affects the central face, namely the cheek, nose, chin, and central forehead. Although rosacea is mainly a disorder of innate and adaptive immunity, a variety of endogenous and exogenous triggers such as Demodex may stimulate it. Often found as commensal organisms in human skin, Demodex ​​​​​​​can be parasitic if there is a change in the host's cutaneous environment. This is especially relevant for immunosuppressed patients, who need prompt treatment to prevent further complications. We review the literature regarding rosacea granulomatosis in immunosuppression and present an acute myelogenous leukemia patient with severe neutropenia, which may have promoted the development of rosacea due to Demodex ​​​​​​​mite proliferation. This local proliferation of the ectoparasite on the face can cause an atypical skin rash that mimics severe infections in the setting of neutropenia.

Defining the Histopathological Term Atypical Intraepidermal Melanocytic Proliferation: A Retrospective Cross-Sectional Study.

BACKGROUND: Atypical intraepidermal melanocytic proliferation (AIMP) is a general term assigned to melanocytic proliferations of uncertain biological potential when a definitive histopathological diagnosis cannot be achieved. There are few data available describing the possibility of malignancy of AIMP, or ways to further define diagnosis. OBJECTIVE: To determine the rate of diagnostic change of AIMP to melanoma or melanoma in situ (MIS) after conventional excision. In addition, to determine the role of immunohistochemistry (IHC) in defining AIMP biopsies. METHODS: Retrospective cross-sectional, single-center review of biopsies with a diagnosis of AIMP with a follow-up conventional excision from 2012-2016 was performed. In a separate analysis, a search was performed for AIMP biopsied lesions in which IHC was subsequently performed. RESULTS: The rate of diagnostic change of AIMP to MIS was 4.8% (8/167) after excision. Punch biopsy was a risk factor for diagnostic change to MIS (odds ratio 12.94, confidence interval 2.56-65.38, P = 0.008). The rate of diagnostic change of AIMP biopsies after examining with IHC was 21.3% (34/160) to MIS and 4.4% (7/160) to melanoma. CONCLUSION: The possibility of malignancy of AIMP lesions must be taken into consideration when counseling patients and when planning treatment options. IHC is a useful tool and should be used in the evaluation of AIMP specimens.

Pigmented Lesions of the Nail Unit.

Pigmented lesions of the nail unit are commonly encountered in the clinical setting. Yet, they often present a unique challenge to clinicians because of a broad differential diagnosis or unfamiliarity with clinical and histopathologic features. A wide variety of causes exist ranging from benign lesions such as subungual hemorrhage to malignant lesions such as subungual melanoma. Identifying the underlying cause is key to appropriate management and follow-up in these patients. Although emerging clinical tools such as dermoscopy can be very useful in evaluation of these lesions, histopathologic analysis remains the gold standard. In this review, we discuss and provide a summary of important clinical and histopathological concepts of pigmented lesions of the nail unit with special focus on longitudinal melanonychia, melanotic macule, melanocytic nevus, subungual melanoma, along with discussion of some nonmelanocytic lesions.