Clustered yellow papules in the posterior axilla of a middle-aged woman.

Naevus lipomatosus cutaneous superficialis (NLCS) of Hoffman-Zurhelle is a rare hamartomatous benign condition first described in 1921. Two clinical variants have been described: a classical form of multiple yellow papules that coalesce to form larger plaques with segmental distribution, and a solitary form also known as pedunculated lipofibroma. We present a case of early-stage NLCS with characteristic histopathological and dermoscopic features.

'Rainbow pattern': a dermoscopic sign of invasive melanoma.

BACKGROUND: The 'rainbow pattern' was initially described as a highly specific dermoscopic feature of Kaposi sarcoma. Since then, it has been reported in many benign and malignant cutaneous tumours, including a few malignant melanomas (MMs). AIM: To determine the frequency and presentation of this dermoscopic pattern in primary cutaneous MMs in comparison to other cutaneous tumours. METHODS: The presence of a rainbow pattern was evaluated in a sample of 1100 dermoscopic images of different melanocytic and nonmelanocytic cutaneous neoplasms. RESULTS: The rainbow pattern was observed in 23 of 245 (9.4%) MM and 44 of 855 (5.1%) non-MM neoplasms. MMs presenting this feature were generally thicker: 82.6% > 1 mm and 43.0% > 2 mm. Compared with non-MMs, rainbow pattern in MMs was more commonly focal (82.7% vs. 36.4% nonfocal, P = 0.001) and associated with > 2 dermoscopic structures associated with MM (100% vs. 9% with fewer, P = 0.001). CONCLUSION: The rainbow pattern is a dermoscopic sign that can occasionally be observed in invasive MMs. In MMs, this feature is usually associated with other dermoscopic criteria of MM and located in a focal and eccentric area, as opposed to a diffuse and isolated presentation in non-MM neoplasms.

Rosettes in actinic keratosis and squamous cell carcinoma: distribution, association to other dermoscopic signs and description of the rosette pattern.

BACKGROUND: Rosettes, a dermoscopic structure characterized by four white points arranged as a 4-leaf clover, supports the dermoscopic diagnosis of actinic keratosis (AK) or squamous cell carcinoma (SCC). OBJECTIVE: The association of rosettes with other dermoscopic structures in AK or SCC and their distribution has not been analysed yet. METHODS: We conducted a prospective study of patients with histologically proven AK or SCC who presented dermoscopic rosettes at initial evaluation. RESULTS: A total of 56 tumours were collected (94.6% AK and 5.4% SCC). Thirty-seven (66.1%) lesions were non-pigmented and 19 (33.9%) pigmented. The most common dermoscopic findings were erythema (53; 94.6%) and scale (42; 75%). White circles were present in 21 lesions (37.5%); pigmented pseudonetwork in 18 (32.1%) and multiple grey to brown dots and globules in 14 (25%). Rosettes were distributed focally in 9 (16.1%) and generalized in 47 (83.9%). The rosette pattern (rosettes as the main structure) was observed only in AK (19; 35.8%). LIMITATIONS: The analysis was not blinded. The distinction between focal distribution (up to 3 rosettes) or generalized could be considered arbitrary. CONCLUSION: The rosette pattern identified in AK may be a specific pattern for AK.

Urticarial exanthema due to hepatitis B in a pregnant woman, mimicking a polymorphic eruption of pregnancy.

Hepatitis B virus (HBV) infection in pregnant women is very rare in western countries, thus, cutaneous manifestation of HBV infection may be confused with a dermatosis specific of pregnancy. We report a 39-year-old woman who presented in her 20th week of pregnancy with a pruritic rash, which consisted of generalized erythematous plaques, some of them with a purple centre. Serology testing showed acute HBV infection, and a biopsy revealed a superficial and interstitial perivascular inflammatory infiltrate of lymphocytes and eosinophils. A diagnosis of exanthema due to acute hepatitis B infection was established. The patient delivered a clinically healthy boy, who was given the first dose of the HBV vaccine and intravenous specific immunoglobulin, followed by the second dose 2 months later, and did not get infected with HBV. To our knowledge, this is the first case describing HBV exanthema in a pregnant woman, which led to early action for the newborn, avoiding vertical transmission and its high prevalence of cirrhosis and hepatocellular carcinoma.

Congenital cutaneous Langerhans cell histiocytosis and cutaneous mastocytoma in a child.

Langerhans cell histiocytosis and mastocytoma are clonal disorders of bone-marrow-derived cells, most commonly seen in the pediatric age. Infiltration of mast cells and Langerhans cells in the same lesion has been published before, but, to our knowledge, this is the first time that the occurrence of two mastocytomas and Langerhans cell histiocytosis is reported. It could be hypothesized that both clonal disorders of bone-marrow-derived cells could have a common origin.

Granulomatous Dermatitis as a Cutaneous Manifestation of Hematologic Disorders: The First Case Associated With Polycythemia Vera and a New Case Associated With Myelodysplasia. / Dermatitis granulomatosa como manifestación cutánea de trastornos hematológicos: primer caso asociado a policitemia vera y un nuevo caso asociado a mielodisplasia.

Granulomatous dermatitis has been associated with hematologic disorders, including the myelodysplastic syndromes. We describe the first case of granulomatous dermatitis associated with polycythemia vera, presenting as large erythematous nodules mimicking panniculitis. We also present the seventh case associated with myelodysplasia, with erythematous plaques on the face and neck, similar to a neutrophilic dermatosis. We consider it particularly interesting for dermatologists to be aware of this dermatosis as a nonspecific manifestation of various hematologic disorders. We suggest performing additional tests (complete blood count) to exclude the possibility that the skin manifestations are the initial sign of hematologic disease. Furthermore, we propose using the broader term, granulomatous dermatitis, to refer to these disorders as, although there are more reports of interstitial forms, cases with a more nodular presentation have also been published, and the importance of the diagnosis derives not from the subtype but from the relationship with an underlying disease.

Are Oral Mucosal Changes a Sign of COVID-19? A Cross-Sectional Study at a Field Hospital. / ¿Son las alteraciones en la mucosa oral un signo de COVID-19? Estudio transversal en un Hospital de Campaña.

BACKGROUND: Coronavirus disease 19 (COVID-19) has many manifestations, including respiratory, thrombotic, neurologic, digestive, and cutaneous ones. Cutaneous manifestations have been classified into 5 clinical patterns: acro-ischemic (pseudo-chilblain), vesicular, urticarial, maculopapular, and livedoid. Oral manifestations have also been reported, but much less frequently. PATIENTS AND METHODS: We performed a cross-sectional study in which we examined the oral mucosa of 666 patients with COVID-19 at the IFEMA field hospital in Madrid in April 2020. RESULTS: Seventy-eight patients (11.7%) had changes involving the oral mucosa. The most common were transient anterior U-shaped lingual papillitis (11.5%) accompanied or not by tongue swelling (6.6%), aphthous stomatitis (6.9%), a burning sensation in the mouth (5.3%), mucositis (3.9%), glossitis with patchy depapillation (3.9%), white tongue (1.6%), and enanthema (0.5%). Most of the patients also reported taste disturbances. CONCLUSION: COVID-19 also manifests in the oral cavity. The most common manifestations are transient U-shaped lingual papillitis, glossitis with patchy depapillation, and burning mouth syndrome. Mucositis with or without aphthous ulcers or enanthema may also be observed. Any these findings may be key clues to a diagnosis of COVID-19.