"A 13-year-old boy developed red-violet lesions, described as ischaemic, on the toes of both feet. He became febrile and unwell and then tested positive for SARS-CoV-2. The lesions became darker, some blistered, and they regressed over a few days. Similar acral lesions occurred in 22 children in Madrid, all of whom had normal coagulation tests and negative tests for lupus anticoagulant; six had skin biopsies, which showed a dense lymphocytic vascular reaction, with small vessel endothelial swelling, and sometimes focal thrombosis; only one had a positive test for SARS-CoV-2 at the time the lesions were apparent. A Chinese report of 7 critically ill patients with COVID-19, available in English abstract, described acro-ischaemic presentations, “including finger/toe cyanosis, skin bulla[e] and dry gangrene."

"A further report described a patient with COVID-19 who had “evidence of ischemia in the lower limbs bilaterally as well as in digits two and three of the left hand”, multiple cerebral infarcts, and positive antiphospholipid antibodies; however, antiphospholipid antibodies can be transiently positive around times of acute infections and acute thrombosis, but may be of no pathophysiological relevance^."

^{"The best current strategies for confronting large vessel thrombosis in COVID-19 are prophylaxis with low-molecular-weight heparin and treatment with full-dose low-molecular-weight heparin with monitoring of anti-Factor Xa. There are no strong hypotheses regarding the pathogenesis of the coagulant effect of COVID-19 to guide therapy. Until the results of masked randomized controlled trials are available, treatments directed against components of putative pathogenic pathways, such as interleukin and complement, should be regarded as experimental."}

^{CEBM University of Oxford} 

Picture: Francisco Avia

 

^{Thrombosis (blood clots) can be life-threatening, yet as a medical condition it is seldom spoken of outside the medical community. The emergence of COVID-19 could have a growing impact on that, given a recognized connection between COVID-19 and blood clots in some patients. The biggest risk factors for the development of blood clots have been certain cancers, surgery and hospitalizations. Clots can form in the leg or the lung; people with a family history or those who are inactive for prolonged periods are at risk of developing blood clots.}

^{And now, it is also known that COVID-19 can become a risk factor in a percentage of cases of the disease. The coronavirus is an illness that appears to be the cause of blood changes that can potentially form blood clots. In the pandemic's early days it was anticipated that quite possibly a high percentage of COVID-19 patients might experience blood clotting. Based on real-life studies researchers believe now that between five and ten percent of hospitalized COVID-19 patients will develop blood clots.}

^{That rate can rise to 30 percent among patients in intensive care, however, a much higher number than pertains in the general hospitalized population. For the most part the risk is seen in hospitalized patients, and not those who remain at home. Needless to say, those who end up in hospital are suffering a more serious effect from the infection, so it makes sense they would stand a greater chance of developing blood clots. With this knowledge hospitalized patients receive a low dose of blood thinner which forms part of their therapeutic care.}

^{At the present time an international clinical trial is under study to discover whether a higher dose of blood thinner could conceivably improve outcomes of patients with COVID-19. Researchers in Ottawa recruited hundreds of volunteers to take part in a study to determine which treatments function best in reducing the risk of developing blood clots for COVID-19 patients to improve their outcomes; judging between the lower and the higher routine dose of blood thinner.}

^{Some of the findings about blood clotting in COVID-19 could possibly be applied to non-COVID-19 patients or those with other infections, according to Ottawa Hospital Research Institute associate scientist Dr.Lana Castellucci who is also a thrombosis physician at the hospital. Thrombosis affects roughly 100,000 Canadians annually, causing 10,000 deaths, according to Thrombosis Canada, which states the condition should be viewed as a health risk equal to high blood pressure, heart attacks and stroke.}