No antibody response in cutaneous manifestations associated with COVID-19: An observational study of 64 cases with microbiological and clinical characterization.

BACKGROUND: The microbiological diagnosis of skin lesions related to COVID-19 is not well known. OBJECTIVE: Perform a microbiological diagnosis in COVID19-related cutaneous manifestations. METHODS: A cross-sectional study was performed with 64 patients with cutaneous manifestations associated with COVID-19 who underwent serological and nasopharyngeal reverse transcription polymerase chain reaction (RT-PCR) for SARS-CoV-2. RESULTS: Out of the 64 patients, 6 patients had positive RT-PCR, with all of them developing SARS-CoV-2 IgG and 4 of them had positive IgM + IgA. Of the 58 patients with negative RT-PCR, 8 cases had positive IgM + IgA and only one of them had IgG seroconversion. Therefore, the infection was demonstrated in 7 cases (10.9%) and was doubtful in 7 other cases (10.9%) who presented negative RT-PCR and presence of IgA + IgM without subsequent seroconversion of IgG. Fifty patients (78.1%) had negative serological tests. The most frequent cutaneous pattern was pseudo-chilblain (48.4%) followed by maculo-papular pattern (26.6%), urticarial lesions (10.9%), vesicular eruptions (6.3%) and livedoid pattern (4.7%). The maculo-papular pattern showed the highest positivity in RT-PCR (3 cases; 17.6%) and serologies (4 cases; 23.5%). Skin lesions developed after the systemic symptoms in most patients (19 cases; 61.3%). CONCLUSIONS: Microbiological confirmation tests may not be an effective diagnostic technique for COVID-related cutaneous manifestations or that attributed lesions are not related to COVID-19. Confounding factors such as adverse drug reaction, serological cross-reactions with other viruses, the low production of antibodies in asymptomatic or mild forms of COVID-19 or its rapid disappearance, increase diagnostic uncertainty.

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.

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.

[Painful nodules on the soles in a pediatric patient: A diagnostic challenge]. / Nodulos plantares dolorosos tras ejercicio intenso en paciente pediátrica: Un reto diagnóstico.

INTRODUCTION: Idiopathic Palmoplantar Eccrine Hidradenitis (IPPH) is a rare neutrophilic derma tosis, with painful erythematous nodules of sudden onset in the plantar or palmoplantar region, in children without other underlying diseases. OBJECTIVE: To present a case that shows the main clinical and histological characteristics of this entity. CLINICAL CASE: 11-year-old girl with a 48-hours history of painful erythematous-violaceous nodules on the right foot plant associated with fever of up to 38.2 °C, with no history of interest except hyperhidrosis and intense exercising on previous days. Given the clinical suspicion of IPPH, a skin biopsy was performed, which showed inflammatory neutrophil infiltration around eccrine sweat glands and neutrophilic abscesses, confirming the diagnosis. Oral NSAIDs and rest were prescribed, with resolution of the lesions in 7 days. CONCLUSIONS: This case demonstrates the most important aspects of this entity, in many cases underdiagnosed, since it can be confused with other pathologies that occur with painful acral nodules, but have different pathogenic and therapeutic implications. To properly identify the IPPH allows preventing an unnecessary alarm, both patients and their parents, as in dermatologists and pediatricians themselves.

Real-world outcomes in patients with malignancy and moderate-to-severe psoriasis treated with guselkumab.

Background: The treatment of psoriasis in patients with a personal history of cancer is a matter of debate and limited evidence is available to guide clinicians. Objectives: To report a multicenter real-life experience of a group of patients with psoriasis undergoing treatment with guselkumab and a history of cancer. Methods: We conducted a multicenter retrospective Spanish study enrolling patients with moderate-to-severe plaque psoriasis and neoplasia being treated with guselkumab for their psoriasis. Results: Twenty patients with moderate-to-severe psoriasis and at least 12 weeks of ongoing treatment were included. For the analysis, a 52 week follow-up period was evaluated in terms of efficacy and safety. Most of the malignancies in these patients were solid tumors. The percentage of patients achieving psoriasis area and severity index ≤3 at week 12 and week 52 was 80% and 87.5%, respectively, whereas 68.8% of patients achieved psoriasis area and severity index ≤1. A 52-week survival rate of 100% in the study population was observed (n = 20), including those patients with concomitant active cancers (n = 14). No adverse effects or dropouts related to guselkumab safety profile were detected. Limitations: Modest sample size and the retrospective nature of the study. Conclusion: Guselkumab not only demonstrates high effectiveness in treating psoriasis but also exhibits a favorable safety profile in patients with neoplasms.

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.

Lower Extremity Skin Ulcer Associated With Neurofibromatosis Type 1: A Case Report.

INTRODUCTION: The association between neurofibromatosis type 1 (NF-1) and vasculopathy has been reported frequently, especially cerebral, intestinal, and peripheral vasculopathy. However, cutaneous vasculopathy is infrequent. CASE REPORT: The authors present the case of a 32-year-old man with a painful ulcer on his left thigh of 3 weeks' duration in the same location as a long-time capillary malformation associated with alopecia. The skin biopsy showed signs of perivascular fibromuscular dysplasia with proliferating myofibroblastic cells. The patient had been treated with various therapeutic options, such as topical antibiotics, oral and intralesional corticosteroids, and oral cyclosporine and intravenous prostanoids. CONCLUSIONS: Cutaneous vasculopathy related to the skin, such as livedo reticularis and ulcers of torpid evolution due to cutaneous vasculopathy are extremely rare. Thus, it is necessary to include skin ulcers as one of the phenotypic manifestations of NF-1.