What is Hughes syndrome?
Hughes syndrome is named after Dr Graham Hughes, who along with his team in London, was the first to describe the condition in 1983.
Also known as ‘sticky blood', it is an autoimmune disorder, in which there is a danger of thrombosis (clotting).
Those affected are at risk from vein thrombosis, including deep vein thrombosis (DVT), and arterial thrombosis, which increases the risk of stroke and heart attack.
In women with the syndrome, the ‘sticky blood' is unable to get through the sensitive small blood vessels in the placenta to the foetus, therefore left untreated, there is a risk of recurrent miscarriage.
The condition affects millions of people around the world although once diagnosed, it can usually be treated successfully. However as it is a relatively new condition, it often goes undetected or is misdiagnosed.
Hughes syndrome is medically known as antiphospholipid syndrome (APS).
What are the symptoms?
It is not necessary to have all symptoms to be diagnosed with Hughes syndrome - the main symptoms can include any of the following:
-Headache or migraine: This is often one of the major features of the condition. Sometimes the headaches disappear when a person is in their 20s, only to return even worse in their 30's or 40's. This symptom sometimes improves dramatically when treatment is started. Migraine features, such as flashing lights and zigzag patterns, often accompany the headaches.
Giddiness: For reasons not completely understood, affected people can have problems with their balance and many complain of feeling giddy or ‘slightly drunk'. This can lead to accidents.
Memory loss: This is a common symptom. Many patients worry they are developing Alzheimer's disease. However once treatment begins, memory improves.
Visual disturbances: In addition to the flashing lights and zigzag patterns which can accompany headaches and migraines, a person with Hughes Syndrome can experience double vision or sudden vision loss.
Skin disorders: Many patients complain of ‘cold circulation' and this sometimes manifests as a blotchy appearance on the skin of the arms and legs. The syndrome can also cause repeated sores (ulcers) and bumps (nodules) on the skin.
Thrombosis, including DVT: Thrombosis, or blood clots, can occur in the untreated patient at any time and in any part or organ of the body.
Heart attack: Hughes Syndrome can lead to heart attacks and heart valve problems in those affected.
Stroke: There are many causes of stroke, however research indicates that one in five strokes in people under the age 45 could be linked to Hughes syndrome.
Pulmonary embolism: A lung embolus (pulmonary embolism) occurs when a blood vessel supplying the lung becomes clogged up by a clot - a lump of coagulated blood. Blood clots in the lung can cause chest pain, shortness of breath and rapid breathing. Repeated clots can cause elevated pressure in the blood vessels around the lungs, which may cause the person to be constantly short of breath. Larger emboli in the lungs can be lethal.
Multiple sclerosis-like features: Some people with Hughes Syndrome develop MS-like features, such as loss of part of the field of vision and difficulty walking. As a result, Hughes syndrome may be wrongly diagnosed as MS.
Gastrointestinal disorders: Hughes Syndrome can affect the blood supply to the intestines, causing abdominal pain, fever and blood in the stool. It can also cause a condition called Budd-Chiari syndrome, in which a clot prevents blood from flowing out of the liver. The person may then experience nausea, vomiting, jaundice, dark urine and swelling of the abdomen.
Pregnancy problems: It is now known that Hughes syndrome is the most common treatable cause of recurrent miscarriage. Late pregnancy loss is also very strongly associated with the syndrome as is pre-eclampsia, placental abruption and intra-uterine growth restriction.
How is Hughes syndrome diagnosed?
Two blood tests are often used to help diagnose the condition, but as they are not totally reliable, they are usually used in combination with the patient's history.
A simple blood test which is used to detect the antiphospholipid antibodies is positive in about 80% of cases. Another test, confusingly called a lupus anticoagulant test (it is not a test for lupus and it is not an anticoagulant) is also used to help confirm the diagnosis - this is positive in about 30-40% of cases.
It is usually advisable to repeat the blood tests on more than one occasion, especially if the results are ‘borderline' or ‘doubtful'. One positive test for antiphospholipid antibodies does not mean that a person has Hughes syndrome. For this reason, the test should be repeated after six to eight weeks.
Tests that are only just positive and that are present on only one occasion may not be significant. This is because harmless antiphospholipid antibodies can be detected in the blood for brief periods, occasionally in association with a wide variety of conditions, including infections and certain drugs (e.g. antibiotics and certain blood pressure pills).
The Sapporo criteria is a classification method used by researchers, which defines Hughes syndrome based on a combination of clinical and laboratory criteria. These criteria are meant for research workers and doctors, and not for the general public, but they include one or more clinical episodes of arterial, venous or small vessel thrombosis in any tissue or organ.
How is the syndrome treated?
Due to the increased tendency to clot, the main aim of treatment is to 'thin' the blood, so that this risk is reduced. For most patients, this is usually achieved by providing anticoagulant (anti-clotting) therapy based on the extent of the clotting.
There are currently three main medications - aspirin, heparin or warfarin. For many thousands of patients, one ‘junior' aspirin a day (equivalent to one-quarter of a regular aspirin) is all that is required. Its main action is to make the platelets of the blood less ‘sticky' and therefore sufficient to hold off clotting. It is the main medication used in pregnancy in Hughes syndrome patients who have suffered a previous miscarriage.
For those who have actually had a thrombosis, the choice is between heparin and warfarin. Heparin is a very useful anticoagulant but unfortunately is only available as an injection, and cannot be given long-term because of an increased risk of osteoporosis. It is, however, used in some Hughes syndrome pregnancies, as warfarin is potentially toxic to the developing foetus.
For most people with thrombosis, warfarin is the treatment of choice. Used for many decades warfarin is the 'gold standard' anticoagulant tablet and provided that the anticoagulation dose is monitored carefully to test that the patients blood is thinning to the correct degree, it is an extremely safe drug.
What is the prognosis?
While there is no cure for Hughes Syndrome, the outlook for patients is dramatically better than in the past. Simple blood tests mean that appropriate, long-term treatment can be given.
Patients can also reduce their risk of thrombosis from causes other than Hughes syndrome, for example, by stopping smoking and maintaining a healthy weight.
Unfortunately, many people's first awareness of Hughes Syndrome is when they suffer a life-threatening medical event, such as a lung clot or a stroke. It is hoped that as the condition becomes more widely recognised by the medical profession, more people will be treated properly.
In relation to miscarriages, a woman's chance of carrying a baby to term may be increased from around 20% to 75-80% if appropriate treatment is administered.