Section of Dermatology, Department of Health Sciences, University of Genoa, IRCCS - Ospedale Policlinico San Martino, Genoa, Italy.
Arch Dermatol Res. 2024 Jul 23;316(7):485. doi: 10.1007/s00403-024-03228-1.
Demodex mite proliferation is frequently involved in the pathogenesis of rosacea. The gold standard for Demodex identification is microscopic examination on a standardized skin surface biopsy. However, this method of sampling can be distressing and painful, especially when performed on hairy sites. In this case-control study, we compared the sensitivity of PCR and microscopic examination in diagnosing a Demodex infestation. Moreover, we investigated the possible correlations between the presence of Demodex mites and clinical characteristics. In total, 20 patients affected by papulopustular rosacea and 10 controls were included. At both microscopic examination and PCR, patients with rosacea presented a greater prevalence of positive samples than controls at the scalp and at the face. Microscopy had sensitivity of 50% at the face and of 46.7% at the scalp. PCR had sensitivity of 93.75% at the face and of 86.7% at the scalp. The positivity of PCR was associated to a higher frequency of facial papules and pustules. Patients with positivity at the face had a more frequent positivity at the scalp. The scalp could represent a reservoir for the Demodex mites, and should be investigated by sensitive and painless methods. PCR performed on painlessly collected samples should be further investigated.
蠕形螨增殖常与酒渣鼻的发病机制有关。蠕形螨鉴定的金标准是在标准化的皮肤表面活检上进行显微镜检查。然而，这种取样方法可能会引起不适和疼痛，尤其是在有毛发的部位进行时。在这项病例对照研究中，我们比较了 PCR 和显微镜检查在诊断蠕形螨感染方面的敏感性。此外，我们还研究了蠕形螨的存在与临床特征之间的可能相关性。共有 20 名患有丘疹脓疱性酒渣鼻的患者和 10 名对照者纳入研究。在显微镜检查和 PCR 检查中，酒渣鼻患者头皮和面部的阳性样本检出率均高于对照组。显微镜检查在面部的敏感性为 50%，在头皮的敏感性为 46.7%。PCR 在面部的敏感性为 93.75%，在头皮的敏感性为 86.7%。PCR 的阳性结果与面部丘疹脓疱的频率更高有关。面部阳性的患者头皮阳性的频率更高。头皮可能是蠕形螨的储存库，应通过敏感和无痛的方法进行检查。应进一步研究无痛采集样本上进行的 PCR。
