Related Experiment Video
Updated: Jul 12, 2026
13:08
Measurement of Factor V Activity in Human Plasma Using a Microplate Coagulation Assay
Published on: September 9, 2012
[Homocysteinemia and thrombophilic factors in unexplained decompression sickness]
M Candito1, E Candito, M Chatel
1INSERM U145 et Biochimie, Hôpital Pasteur, Centre Hospitalier Universitaire, Nice.
Revue Neurologique
|October 10, 2006
Summary
Divers experiencing unexplained decompression sickness may have elevated homocysteine and deficiencies in folate or vitamin B12. Genetic factors like MTHFR mutations also contribute to this risk, suggesting simple blood tests for prevention.
Area of Science:
- Diving Medicine
- Hematology
- Genetics
Background:
- Decompression sickness with cerebral ischemic lesions can occur in divers without apparent technical errors.
- This suggests underlying acquired or inborn thrombophilic factors may be involved.
Purpose of the Study:
- To investigate the potential role of thrombophilic factors in divers experiencing unexplained decompression sickness.
- To compare coagulation and metabolic factors between divers with ischemic medullar lesions and healthy controls.
Main Methods:
- Compared 44 divers with ischemic medullar lesions to 44 controls.
- Assayed coagulation factors, Factor V Leiden, Factor II gene mutation G20210A, plasma homocysteine (Hcy), folate, vitamin B12, and MTHFR gene mutation C677T.
Main Results:
- No significant differences in standard coagulation screening or Factor V Leiden/Factor II G20210A mutations compared to general population rates.
- Elevated homocysteine (Hcy) and deficiencies in folate or vitamin B12 were significantly more common in divers (20% and 27% respectively) than controls (2.3%).
- A higher prevalence of homozygous MTHFR C677T mutation was observed in divers (27%) compared to controls (12%).
Conclusions:
- Unexplained diving accidents are associated with moderate hyperhomocysteinemia (HHC), folate/vitamin B12 deficiencies, and genetic predisposition.
- Simple assays for homocysteine, vitamin B12, and folate may aid in the primary prevention of diving accidents.
More Related Videos
Related Concept Videos
01:30Anticoagulant Drugs: Low-Molecular-Weight Heparins
Hemostasis is a crucial process that prevents excessive blood loss from damaged blood vessels. It involves various mechanisms such as vasoconstriction, platelet adhesion and activation, and fibrin formation. The importance of each mechanism depends on the type of vessel injury. In contrast, thrombosis is the abnormal formation of a blood clot within the blood vessels, leading to potential complications if the clot obstructs blood flow. Thrombosis can be caused by increased coagulability of the...
01:24Disorders of Hemostasis
Hemostasis, the process that stops bleeding after a blood vessel injury, is crucial for maintaining the integrity of the circulatory system. However, disorders of hemostasis can disrupt this delicate balance, leading to either excessive clotting or bleeding. These disorders can be broadly classified into thromboembolic disorders and bleeding disorders.
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
Thromboembolic Disorders
Two factors primarily cause thromboembolic conditions.
01:30Venous Thrombosis I: Introduction
Venous thrombosis, the most common disorder of the veins, involves the formation of a thrombus or blood clot associated with vein inflammation. It can be classified as either superficial vein thrombosis or deep vein thrombosis.Superficial Vein Thrombosis: This involves the formation of a thrombus in a superficial vein, usually the greater or lesser saphenous vein. Though less severe than deep vein thrombosis (DVT), SVT can lead to complications if untreated.Deep Vein Thrombosis (DVT): This...
01:20Venous Thrombosis II: Clinical Manifestations and Diagnostic Studies
The key difference between Superficial Vein Thrombosis (SVT) and Deep Vein Thrombosis (DVT) lies in their location and severity.Clinical ManifestationsSVT typically presents with localized pain, tenderness, and redness along the course of a superficial vein, often accompanied by a palpable, cord-like structure under the skin. This condition is usually less dangerous than DVT but can be uncomfortable and may lead to complications such as cellulitis or, rarely, a clot extension into the deep...
01:29Pulmonary Embolism I: Introduction
Pulmonary embolism (PE) occurs when a thrombus, fat or air embolus, amniotic fluid, or tumor tissue blocks one or more pulmonary arteries. These blockages originate in the venous system or the right side of the heart.EtiologyPE primarily arises from deep vein thrombosis (DVT) and other hypercoagulable states, such as inherited thrombophilias. Additional etiological factors include venous stasis, commonly seen in obesity, and endothelial injury from surgery and trauma. Less common causes include...
01:19Pulmonary Embolism I: Introduction
A blood clot, or thrombus, is a semi-solid mass composed of fibrin, platelets, and red blood cells. When it forms within a vessel, it can obstruct blood flow, known as thrombosis. If part of the clot detaches, it becomes an embolus that can travel and block distant vessels. When this occurs in the pulmonary arteries, it causes a condition known as pulmonary embolism (PE).Origin and ImpactMost often, the embolus originates from a thrombus in the deep veins of the lower limbs, a condition called...