Otorhinolaryngology, Faculty of Medicine, Department of Clinical Sciences, Malmö, Lund University, Malmö, Sweden.
Skin Res Technol. 2022 Jan;28(1):54-57. doi: 10.1111/srt.13089. Epub 2021 Oct 7.
A histamine skin prick test (SPT) generally evokes a wheal and a flare. The present study was initiated by an observation that histamine did not evoke a flare around a wheal in the skin of an 86-year-old man. Could that be of relevance to the findings that old men are prone to a more severe COVD-19 infection with a higher mortality than young ones?
Histamine SPT was performed on the forearm of six old men, all above the age of 80. The skin reactions were photographed from above and from the side. The photographs taken from above were treated in a computer with LYYN, a program that increases color differences. With the help of ImageJ (NIH), the size relation between flare and wheal was calculated. On the photographs, taken as side views, areas, heights, and diameters of wheals were measured. Controls consisted of three groups of younger people.
Among the old men, no or only a small flare was seen. All the controls had prominent flares. Histamine SPT evoked small wheals in the group of old men as compared to young men.
Reduced neurogenic inflammation evoked by histamine from mast cells in blood and tissue may reduce the defense against COVID-19 infection.
组胺皮肤点刺试验（SPT）通常会引起风团和红晕。本研究最初是观察到在一名 86 岁男性的皮肤中，组胺在风团周围不会引起红晕。这与老年人 COVID-19 感染更严重、死亡率高于年轻人的发现是否有关？
对 6 名 80 岁以上的老年人前臂进行组胺 SPT。皮肤反应从上方和侧面拍摄。用 LYYN 程序对上方拍摄的照片进行处理，该程序可以增加颜色差异。借助 ImageJ（NIH）计算红晕和风团之间的大小关系。在侧面拍摄的照片上测量风团的面积、高度和直径。对照组由三组年轻人组成。
老年人中观察到无或仅有小的红晕。所有对照组均有明显的红晕。与年轻人相比，组胺 SPT 在老年人中引起的风团较小。
血液和组织中肥大细胞释放的组胺引起的神经源性炎症减少，可能会降低对 COVID-19 感染的防御。
