Skin capillary alterations in patients with acute SarsCoV2 infection

Abstract

Background: Acute SarsCov2 infection is associated with endothelial dysfunction and 'endothelitis', which might explain systemic microvascular impairment. The presence of endothelial damage may promote vasoconstriction with organ ischemia, inflammation, tissue oedema and a procoagulant state resulting in an increase in the incidence of cardiovascular and cerebrovascular events. Microvascular thrombosis has been demonstrated in postmortem autopsy of COVID-19 patients; however, few data are available about skin capillary alterations in these patients. Materials and methods:We evaluated skin microvascular alteration in 22 patients admitted to our hospital with SarsCov2 infection. Capillary density was evaluated by capillaroscopy in the nailfold and the dorsum of the finger in the acute phase of the disease. Capillaroscopy was repeated after 3 months (recovery phase). In addition, blood chemistry parameters and inflammatory markers were obtained during acute infection and at the recovery after 3 months.Results: Patients with COVID-19 showed skin microvascular complications, such as thrombosis, microhaemorrhages and neoangiogenesis, which were not detected after 3 months from the discharge. A significant reduction of capillary density in the dorsum was observed after 3 months from the acute infection (97.2 AE 5.3 vs. 75.81 AE 3.9 n/mm 2 P < 0.05). A significant inverse correlation between C-reactive protein and capillary density was observed in patients with acute SarsCov2 infection (r ¼ 0.44, P < 0.05). Conversely a direct correlation between capillary density during the acute phase and lymphocyte number was detected (r ¼ 0.49, P < 0.05). Conclusion:This is the first in-vivo evidence of skin capillary thrombosis, microhaemorrhages and angiogenesis in patients with acute SarsCov2 infection, which disappeared after 3 months, supporting the presence of endothelial dysfunction and inflammation. Capillary alterations might reflect systemic vascular effects of viral infection.

Comparison of nailfold capillaroscopy findings in COVID-19 survivors with and without rheumatic disease: a case-control study

“…Sulli et al 21 found that even in people with severe COVID-19, antivirals and biologics (such as IL-6 receptor antagonists) have a protective effect on capillary density. As the time from a SARS-CoV-2positive RT-PCR test to NFC exceeded 10 weeks in both patients and HCs, the capillaroscopic changes shown to return three months after COVID-19 by Rosei et al 22 may be another factor contributing to the similarity of capillary findings among the study groups. Further studies are needed to determine the conditions under which COVID-19 induces capillary changes or whether the resulting changes are reduced.…”

“…Similarly, Karahan et al 19 found that patients with COVID-19 had a lower capillary density than HCs, and those who died of COVID-19 had a lower capillary density than those who survived. In addition, the systemic vascular effects of the virus are evidenced by changes such as capillary thrombosis, microhemorrhages, and angiogenesis detected during COVID-19, which disappeared in controls 3 months after discharge 22 . In the present study, the NFC findings did not differ among the groups, except for capillary ramifications.…”

Telogen effluvium in SARS‐CoV‐2 infection: Histological aspects

“…This may result in a state of endothelitis with microvascular inflammation and capillary thrombosis mediated by cytokine storm and macrophage activation syndrome. 3 Another additional proposed mechanism was the antibody-dependent enhancement (ADE), due to the presence of non-neutralizing virusspecific antibodies (NAb), capable to promote Fcγ-mediated virus entry into the host cells. 4 Herein we describe the histopathological features of CrTE.…”

Observation and density estimation of a large number of skin capillaries using wide-field portable video capillaroscopy and semantic segmentation

“…For instance, the shapes of the nailfold and labial mucosa capillaries change due to systemic scleroderma 3 – 5 and chronic smoking, 6 respectively. Recent studies have suggested that COVID-19 may also be detected based on the changes in capillaries 7 , 8 . In capillaroscopy images, only the capillaries containing red blood cells (RBCs) are visible.…”

“…Recent studies have suggested that COVID-19 may also be detected based on the changes in capillaries. 7 , 8 In capillaroscopy images, only the capillaries containing red blood cells (RBCs) are visible. Accordingly, by regarding observable capillaries as “functioning” capillaries, the quantification of the functional capillary density (FCD) was proposed.…”