Microclots

Microclots or micro-clots are extremely small blood clots, and have been found in some Long COVID patients and in an initial study of ME/CFS patients.

ME/CFS
In 2022, Nunes et al. found fibrinaloid microclots in ME/CFS patients, which they suggested was the result (rather than the cause) of post-viral illness.

Long COVID
Microclots are a recognized symptom of Long COVID. They may result in reduced oxygen flow to large muscles; a hypothesis is that this reduced oxygen availability causes the post-exertional malaise or and/or exercise intolerance reported by some people with Long COVID.

Possible treatments
Rivaroxaban is an anti-clotting drug being investigated as a possible treatment for Long COVID patients with microclots.

Nattokinase is an enzyme derived from Natto, a popular traditional Japanese food made from soybeans fermented by Bacillus subtilis var. natto. Nattokinase has the highest clot-dissolving potency among naturally known anticoagulants. A clinical trial demonstrated that oral consumption of nattokinase was not associated with any adverse effects. Thus, nattokinase is now considered an efficient, secure, and economical enzyme that has drawn central attention in thrombolytic drug studies.

Notable studies

 * 2022, The Occurrence of Hyperactivated Platelets and Fibrinaloid Microclots in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) - (Full text)

News and articles

 * 2022, Chronic fatigue syndrome may be caused by mini blood clots - New Scientist

Learn more

 * STIMULATE-ICP trial for Long COVID