Dermoscopy of haemosiderotic/aneurysmal dermatofibroma: A morphological study of 110 cases.

BACKGROUND: Haemosiderotic and aneurysmal dermatofibromas are uncommon and frequently misdiagnosed lesions, which can be considered as different histopathological stages of the same tumour. A dermoscopic diagnosis testing accuracy has not been performed for these tumours to date. OBJECTIVES: To determine the diagnostic significance of dermoscopic structures and patterns associated with haemosiderotic/ aneurysmal dermatofibromas in a large series. METHODS: Dermoscopic images of histopathologically proven cases of 110 haemosiderotic/ aneurysmal dermatofibromas and 501 other tumours were collected. The frequency, sensitivity, specificity, positive predictive value and negative predictive value of the dermoscopic structures and patterns associated with these lesions were calculated. RESULTS: Haemosiderotic/ aneurysmal dermatofibromas are mostly symmetric lesions (86.5%), and a prominent homogeneous area was present in 100% of them. The presence of vascular structures was very common (86.4%), and dotted vessels were predominant (58.2%). Shiny white structures were seen in 85.5% of lesions, while a peripheral delicate pigment network was present in 69.1%. The most significant pattern was the one composed of a prominent homogeneous area and peripheral delicate pigment network, which showed a specificity of 100% with a relatively good sensitivity (69.1%). All the patterns containing a peripheral delicate pigment network showed very good specificities, positive predictive values and negative predictive values. Those patterns without a peripheral delicate pigment network showed the highest sensitivities, but they showed a significant overlap with other tumours, mainly with melanoma. CONCLUSIONS: Dermoscopy is helpful in improving the diagnostic accuracy of haemosiderotic/ aneurysmal dermatofibromas. However, there is a considerable dermoscopic overlap between these tumours and melanoma, specifically when the peripheral delicate pigment network is absent.

SUFU-associated Gorlin syndrome: Expanding the spectrum between classic nevoid basal cell carcinoma syndrome and multiple hereditary infundibulocystic basal cell carcinoma.

Basal cell nevus syndrome (BCNS), also known as Gorlin syndrome, is characterized by an aberrant activation of the hedgehog (Hh) pathway, most cases being caused by PTCH1 mutations. However, certain features such as multiple hereditary infundibulocystic basal cell carcinomas (MHIBCC), sclerotic fibromas, childhood medulloblastoma or meningioma may be relatively specific to a SUFU mutation. We present two patients with MHIBCC, along with a more complex cutaneous and extracutaneous phenotype. MHIBCC syndrome and BCNS may share clinical features and, indeed, both syndromes probably represent different degrees of upregulation in the Hh pathway.

The Usefulness of Dermoscopy for the Recognition of Malignant Collision Tumors.

BACKGROUND: Preoperative diagnosis of malignant collision tumors (MCT) is extremely difficult. The value of dermoscopy to improve the correct detection of these tumors has not been previously studied. This study aims to evaluate the diagnostic accuracy of MCT with and without dermoscopy and to describe the dermoscopic features of a large series of MCT. METHODS: Dermoscopic images of 161 MCT were evaluated. Clinical and dermoscopic images of histopathologically proven MCT intermingled with other tumors were randomly presented to clinicians with different levels of experience, blinded to the diagnosis and objective of the study. The clinical and dermoscopic diagnostic accuracies were measured separately. RESULTS: A total of 161 histopathologically proven cases of MCT were collected. The most frequent MCT was basal cell carcinoma-seborrheic keratosis collision tumor (CT; 37.9%), followed by basal cell carcinoma-melanocytic nevus CT (19.9%), and melanoma-seborrheic keratosis CT (6.8%). Diagnostic accuracy among experts on dermoscopy was 71.4%. The study included 119 participants. The percentage of correct diagnoses was 8% by naked eye examination and 36.4% by dermoscopy (p < 0.001). The presence of the malignant component in the cases of MCT was not recognizable in 19.1% of cases by naked eye examination and in 11.8% of cases by dermoscopy (p < 0.001). CONCLUSIONS: The diagnosis of MCT can be assisted and clarified by dermoscopy. However, many of these lesions manifest complex morphologies and continue to be challenging, even for experts on dermoscopy. Atypical, uncertain, or non-classifiable lesions still need a complete excision for the final diagnosis.

Dermoscopy of inflamed seborrheic keratosis: A great mimic of malignancy.

BACKGROUND: Clinical and dermoscopic recognition of seborrheic keratoses (SKs) is often straightforward, and biopsy might not be required. However, inflamed SKs (iSKs) can pose a diagnostic challenge. Dermoscopic features of iSKs have not yet been evaluated to date. OBJECTIVES: To assess the diagnostic ability of a group of dermatologists to diagnose iSKs by dermoscopy. To evaluate the dermoscopic findings of a long series of inflamed seborrheic keratoses. METHODS: Clinical and dermoscopic images of 100 difficult-to-diagnose skin tumours, including 29 iSKs, were presented to 33 clinicians (24 dermatologists and 9 dermatology residents), who were blinded to the diagnosis. The dermoscopic features of a series of 219 iSKs were retrospectively analysed. RESULTS: iSKs were correctly identified in a 37.6% of cases. Classic dermoscopic criteria were present in only 47% of iSKs. The most frequent dermoscopic feature in iSKs was the presence of vascularization (91.3%), but only a 44.5% showed predominance of hairpin vessels. A bluish hue was observed in 18.3% of lesions. Seven dermoscopic patterns were identified, based on the dermoscopic similarity to other tumours: seborrheic keratosis-like (28.8%); squamous cell carcinoma-like (25.6%); melanoma-like (17.8%); keratoacanthoma-like (6.8%); basal cell carcinoma-like (5.9%); verruca vulgaris-like (5.9%); nevus-like (2.3%). CONCLUSIONS: The diagnosis of iSKs can be challenging even with dermoscopy. They may behave as authentic mimics of other cutaneous tumours, including squamous cell carcinoma or melanoma. For this reason, histopathological examination should be mandatory in these cases.

Flame Figures in Linear Immunoglobulin A Bullous Dermatosis Secondary to Parvovirus B19 Infection.

ABSTRACT: Flame figures represent a characteristic but nondiagnostic histological finding in eosinophilic dermatoses. Some bullous autoimmune diseases with a predominant eosinophilic infiltrate, such as bullous pemphigoid, pemphigoid gestationis, and pemphigus vegetans, may show them. However, it is rare to find them in predominant neutrophilic bullous dermatoses such as linear immunoglobulin A. We present a 60-year-old man with a history of chronic urticaria, which presented a bullous disease after an acute parvovirus B19 infection. The histological findings showed an exceptional linear immunoglobulin A bullous dermatosis with an eosinophilic infiltrate in the dermis forming "flame figures." The clinical and histopathological findings for this entity may be identical to those of other dermatoses. For this reason, combining these findings with direct immunofluorescence analysis is essential for correct diagnosis of this bullous disease.

Plaque-like cutaneous mucinosis of childhood.

A healthy 10-year-old boy presented with plaque-like cutaneous mucinosis (PCM) on his back. Cutaneous biopsy was followed by progressive resolution of the skin lesion. Pediatric PCM could differ clinically from the adult form. However, more cases are necessary to draw conclusions.

Multifocal pyoderma gangrenosum secondary to subclinical diverticulitis: case report and brief literature review.

Pyoderma gangrenosum is characteristically associated with inflammatory bowel disease. However, the association between this neutrophilic dermatosis and diverticular disease is scarcely mentioned in the literature. Diverticulitis should be included in the differential diagnosis in patients with pyoderma gangrenosum and gastrointestinal complaints, or even in asymptomatic patients, particularly in the elderly. Misdiagnosis can lead to inadequate treatments and serious complications.

Saturday night purpura: An uncommon presentation of exercise-induced vasculitis.

Exercise-induced vasculitis (EIV) is a benign cutaneous vasculitis that affects healthy individuals. We report a case of EIV in a 15-year-old male patient with a striking clinical appearance triggered by a combination of prolonged standing and disco dancing in a warm environment. Pediatric dermatologists should be aware of this activity as a possible trigger of EIV, especially in teenagers.

Exogenous acral pigmentation induced by coleoptera: an underdiagnosed mimic of severe disease.

Acral purpura is generally a hallmark for severe internal disease. However, exogenous pigmentation related to contact with invertebrates, can induce acral purpura-like lesions. Data regarding the beetle's ability to cause skin hyperpigmentation or purpura-like lesions are scarce. We report a case of exogenous pigmentation caused by accidental contact with a darkling beetle, clinically simulating acral purpuric lesions. The history of recent drug inhalation and abnormal autoimmunity tests made this diagnosis difficult.

Demodicosis in two patients with a previous history of Langerhans cell histiocytosis.

Demodex mites are commensal organisms rarely found in healthy children. Human demodicosis can be classified as a primary or a secondary form. The secondary form in children usually affects severely immunodepressed children. To our knowledge, this is the first report of human demodicosis associated with Langerhans cell histiocytosis. These cases show that this skin disorder can occur months after completing chemotherapy, without recurrence of the systemic disease.

Topical Immunotherapy for Actinic Keratosis and Field Cancerization.

This comprehensive review delves into various immunotherapeutic approaches for the management of actinic keratoses (AKs), precancerous skin lesions associated with UV exposure. Although there are treatments whose main mechanism of action is immune modulation, such as imiquimod or diclofenac, other treatments, apart from their main effect on dysplastic cells, exert some immunological action, which in the end contributes to their efficacy. While treatments like 5-fluorouracil, imiquimod, photodynamic therapy, and nicotinamide are promising in the management of AKs, especially in immunocompetent individuals, their efficacy is somewhat reduced in solid organ transplant recipients due to immunosuppression. The analysis extends to optimal combination, focusing on cryoimmunotherapy as the most relevant. New immunotherapies include resimiquimod, ingenol disoxate, N-phosphonacetyl-L-aspartate (PALA), or anti-PD1 that have shown promising results, although more studies are needed in order to standardize their use.

Cutaneous Alternariosis in Immunosuppressed Patients Treated with Photodynamic Therapy and Oral Antifungals, a Synergistic Strategy.

Cutaneous alternariosis is a rare condition, more frequently presented in immunocompromised patients, which usually requires long courses of systemic antifungals that may interact with other medications. The presented series shows three cases of cutaneous alternariosis in immunocompromised patients and organ transplant recipients that were successfully treated with photodynamic therapy and oral antifungals, allowing a reduction in the systemic treatment duration and therefore decreasing the risk of side effects and drug interactions.

Neutrophilic dermatosis of the dorsal hands related to cocaine abuse.

Neutrophilic dermatoses encompass a wide spectrum of diseases characterized by a dense infiltration mainly composed of neutrophils. Neutrophilic dermatosis of the dorsal hands is currently considered a localized variant of Sweet syndrome. Cocaine abuse has been related to a wide range of mucocutaneous manifestations, including neutrophilic dermatoses such as pyoderma gangrenosum. The authors of this study present a patient with neutrophilic dermatosis of the dorsal hands, in which cocaine abuse was identified as a probable trigger.

Generalized granuloma annulare after pneumococcal vaccination.

Granuloma annulare may be caused by multiple triggers. Among these are vaccinations, which have been described as an infrequent cause of granuloma annulare. The authors report the first case of generalized granuloma annulare associated with pneumococcal vaccination in a 57-year-old woman, who presented cutaneous lesions 12 days after vaccination.

Pyemotes ventricosus Dermatitis: Comet-Shaped Skin Lesions after Contact with Woodworm-Infested Furniture.

A 23-year-old woman presented to our dermatology clinic for the sudden onset of pruritic lesions on her forearms and legs for the past two days ago. She had been restoring used furniture infested with woodworm. We observed many oval "comet-shaped" erythematous maculopapules with a serpiginous track on the exposed parts of her forearms and legs (Figure 1). Considering the temporal relationship and the contact with woodworm, we were able to diagnose it as Pyemotes ventricosus. We prescribed topical corticosteroids twice daily. By the 8th day, the lesions had cleared.