Lack of awareness on blood clots worries medics.
Many Kenyans could be dying from blood clots without getting any diagnosis, a medic has warned.
The condition can be prevented easily, and can kill quickly if untreated.
Dr Harun Otieno, a cardiologist at the Aga Khan University hospital, says the most at risk people include those with cancer, had surgery, long hospital admission and sedentary lifestyle.
'In Kenya the peak age is 40 years but it can affect people of any age,' he says.
Dr Otieno says pulmonary embolism, where a clot develops in the lungs, has especially high mortality rate.
'A recent study at Kenyatta National Hospital showed 28 per cent or one in every four patient died despite treatment,' he says.
The study was conducted by University of Nairobi's Prof Julius Ogeng'o, who analysed records of pulmonary embolism patients at KNH between January 2005 and December 2009.
"Ninety-two patients (71.9 per cent) recovered, 18.8 per cent of them with cor pulmonale, while 28.1 per cent died. Pulmonary embolism is not uncommon in Kenya. It affects many individuals below 40 years without a gender bias, and carries high morbidity and mortality," says the study.
"Tragically, many lives are lost because public awareness about life-threatening blood clots is so low," Dr Otieno told the Star in an interview.
Blood clots occur when blood thickens and clumps together.
Usually, clotting is a necessary process that can prevent you from losing too much blood, for instance, when you're injured or cut.
However, when a clot forms inside one of your veins, it may not dissolve on its own and it can be life-threatening.
While a stationary blood clot generally won't harm you, there's a chance that it could move and become dangerous.
'If a blood clot breaks free and travels through your veins to your heart and lungs, it can get stuck and prevent blood flow. This is a medical emergency,' Dr Otieno says.
This complication, called pulmonary embolism, can be fatal.
Blood clots can also permanently damage the veins. Many victims of deep vein thrombosis (which occurs when a blood clot forms in the deep veins, usually of the pelvis or leg) complain of long-term leg pain, heaviness and swelling that can progress to difficulty in walking, changes in skin color and open leg sores.
Dr Otieno advises high suspicion for blood clots when people experience some of these symptoms, including unexplained shortness of breath and fainting.
Clots generally can be prevented by moving around. Medics can also give bed-ridden patients some stockings that help circulation of blood. Blood thinners can also be prescribed.