Perform a microbiological diagnosis in COVID19-related cutaneous manifestations.
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.
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%).
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.
对COVID19相关的皮肤表现进行微生物学诊断。
对64例与COVID-19相关的皮肤表现患者进行了横断面研究,这些患者接受了SARS-CoV-2的血清学和鼻咽逆转录聚合酶链反应(RT-PCR)。
在64名患者中,6例患者RT-PCR阳性,所有患者均发展为SARS-CoV-2IgG,其中4例IgMIgA阳性。在58例RT-PCR阴性的患者中,8例IgM+IgA阳性,仅1例IgG血清转换。因此,7例(10.9%)出现感染,其他7例(10.9%)出现RT-PCR阴性,IgA+IgM存在,但随后IgG无血清转换.50例患者(78.1%)的血清学检查呈阴性。最常见的皮肤模式是假性冻疮(48.4%),其次是黄斑丘疹(26.6%),荨麻疹病变(10.9%),水泡疹(6.3%)和livedoid模式(4.7%)。黄斑丘疹型在RT-PCR(3例;17.6%)和血清学(4例;23.5%)中阳性最高。大多数患者(19例;61.3%)在全身症状后出现皮肤病变。
微生物确认试验可能不是COVID相关皮肤表现或与COVID-19无关的归因于病变的有效诊断技术。药物不良反应等混杂因素,与其他病毒的血清学交叉反应,无症状或轻度形式的COVID-19抗体产量低或迅速消失,增加诊断的不确定性。