Blood Clotting Disorder Lupus Anticoagulant

Lupus anticoagulants — also known as LA or lupus inhibitors — are antibodies that attack plasma proteins in the blood. Normally, antibodies help prevent infections by attacking foreign cells in the body, such as bacteria or viruses. In the case of the lupus anticoagulant, however, antibodies see plasma proteins as foreign bodies and threats, leading to a high risk of clotting.

Approximately 2 percent to 4 percent of the population has lupus anticoagulant in its blood.

Systemic Lupus Erythematosus

Lupus anticoagulants are often found in people who have systematic lupus erythematosus. Also called SLE or lupus, this is an autoimmune disease in which a person’s autoimmune system attacks the body instead of protecting it. The autoimmune system may attack different parts of the body, including the blood vessels, brain, heart and joints.

Women are approximately eight times more likely to develop lupus than men. African Americans are more likely to develop lupus, followed by people of Japanese and Chinese descent. While lupus can develop at any time, lupus frequently starts between the ages of 20 and 45.

Currently, lupus can be treated but not cured. Although lupus can be life-threatening, most patients lead active lives. People with lupus often go through periods of remission and then have the disease reoccur.

Lupus Anticoagulants and Other Conditions

Medical professionals estimate that 20 to 45 percent of people with lupus inhibitors have systematic lupus erythematosus. Lupus anticoagulants also appear in people with:

  • Crohn’s disease
  • HIV
  • Infections
  • Medications, including birth control pills, quinine or amoxicillin
  • Tumors.

A very small percentage of the population has lupus anticoagulants for no apparent reason.

Lupus Inhibitors Symptoms

Many people who test positive for lupus anticoagulants are asymptomatic, meaning they don’t have any symptoms at all. When lupus anticoagulant symptoms do occur, they may include:

  • Abnormal menstrual cycles
  • Bleeding of the nose or gums
  • Blood clots in the legs (deep vein thrombosis) or in the lungs (pulmonary embolism)
  • Bruising
  • Heart attacks
  • Multiple miscarriages
  • Skin rashes
  • Strokes.

If you experience any of these symptoms, schedule an appointment with your doctor. If left untreated, LA can be life threatening.

In order to diagnose lupus anticoagulant, your doctor will perform a blood test. If positive, the test for lupus anticoagulant is repeated at least six weeks later to protect against false positives.

Lupus Anticoagulant Treatments

In many cases, LA doesn’t require any treatments. If the patient doesn’t have a history of problems with lupus anticoagulant, he may simply be monitored. If LA is caused by medications, your doctor will likely ask you to stop taking these drugs. Generally speaking, these patients’ blood tests will return normal results within two to three weeks.

LA patients who are also experiencing blood clots will be given medications, such as Heparin and Coumadin®, to thin the clots and blood. Physicians may also request that lupus anticoagulant patients take aspirin as a blood thinner. In some cases, patients must take drugs for a prolonged period of time or even for the rest of their lives.


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