Rare condition that made a nurse go blind overnight
Faith Mwangi, a Takayasu's arteritis warrior who lost her sight to the rare disease.
What you need to know:
- Takayasu's arteritis is a chronic inflammatory condition that attacks the aorta, the body's largest artery, and the major blood vessels branching off it.
- Over time, the walls of these vessels thicken, narrow, or weaken.
- In its advanced stages, the disease is often known as 'pulseless disease' because the arteries in the arms can narrow so severely that a pulse becomes weak or impossible to find.
Two years ago, on a January morning in 2024, Faith Mwangi woke up to a world that had gone dark on one side. Her right eye had simply stopped seeing.
She rushed to an ophthalmologist, expecting drops or perhaps glasses, hoping her sight would be restored. Instead, the doctor told her that a blood clot had travelled through her body and lodged itself in an artery feeding her eye, cutting off blood flow. The damage was already done and irreversible.
“The ophthalmologist told me that if the blockage had been caught within minutes, my sight might have been saved. It hadn't been. By the time I sat in his office, the window had long closed,” says Faith.
The eye specialist suspected the clot hadn't formed in the eye itself but had travelled from elsewhere in the body, so he sent Faith to a cardiologist. That doctor ran the standard battery of tests. Nothing showed up. “My heart looked fine on paper,” Faith says.
It was only when she was referred for a CT angiogram, a detailed scan of her blood vessels, that something finally appeared on an image. Her right carotid artery, one of the main vessels supplying blood to the brain, was dangerously narrow. Follow-up blood tests measuring inflammation came back elevated. She was finally diagnosed with Takayasu’s arteritis, three months after her first visit to the doctor.
Takayasu's arteritis is a chronic inflammatory condition that attacks the aorta, the body's largest artery, and the major blood vessels branching off it. Over time, the walls of these vessels thicken, narrow, or weaken. In its advanced stages, the disease is often known as 'pulseless disease' because the arteries in the arms can narrow so severely that a pulse becomes weak or impossible to find.
In retrospect, Faith realises that the early symptoms of the disease manifested a year before her diagnosis, with unending fatigue at the end of every day. She didn't think much of the tiredness at first. She was newly a nurse then, and exhaustion after a long shift felt ordinary.
When her blood pressure readings ran high, she blamed genetics because her father and brother both had hypertension. It was only later that she noticed the pressure readings were never the same in both arms. One side always read higher than the other. She didn't know it yet, but that asymmetry was a symptom.
Following the March 2024 diagnosis, the narrowing progressed, accompanied by dizziness and migraines she hadn't connected to anything serious. A repeat CT scan showed the artery had narrowed by 95 per cent. Her doctors warned her of the risk of stroke and other brain- or heart-related complications, and recommended bypass surgery to prevent one.
She eventually underwent lifesaving surgery in July 2026. Surgeons performed a bypass on her carotid artery to restore normal blood flow to the brain, routing blood around the narrow area using a healthy graft vessel. The procedure is ideally performed after inflammation has quieted down with medications like steroids.
Before the surgery happened, Faith began a routine that has defined her life ever since the diagnosis, and one she will continue forever. It includes monthly hospital visits for a biologic infusion meant to calm an immune system that, in her case, attacks the arteries rather than the joints or gut, alongside daily medication for steroids, blood pressure, and cholesterol. All these manage the condition, as it has no cure.
What has struck Faith most, she says, is how differently the disease behaves from patient to patient. Through others she has connected with who share the diagnosis, she describes one person affected in the shoulder, another in the kidney. Doctors have called it an "invisible disease" precisely because of that unpredictability. As far as she knows, no one else in her family has been diagnosed with it, though she mentions one relative whose earlier blood clots were never fully explained.
Dr Etau Ekwom, a Nairobi-based rheumatologist who has treated Faith, says the disease is one of the rarest a doctor will encounter in a rheumatology practice in Kenya, and one of the hardest to study precisely because so few people have it.
“It's a very rare disease, so it's very difficult to say the prevalence. Even within the population of patients who are in a rheumatology practice, it will be less than one per cent,” says Dr Ekwom.
Doctors believe it is an autoimmune disorder, where the body's immune system mistakenly attacks its own blood vessels. Dr Ekwom explains that while nobody fully understands the exact triggers, certain patterns have emerged globally.
“There's a genetic risk; it's more common in younger females than males. Sometimes it's associated with certain infections in other countries, such as tuberculosis, but it is an autoimmune disease,” says Dr Ekwom.
The disease shows a curious geographic and gender pattern. It is more frequently documented in Japan and other parts of Asia, and overwhelmingly affects young women, typically between the ages of 10 and 40. Dr Ekwom says researchers link this to a combination of specific genes and the role of female hormones.
"Most autoimmune diseases are common in women. It is thought that female hormones play a role in increasing the risk of autoimmunity.”
He notes that the disease often masquerades as nothing more than a general feeling of being unwell, before announcing itself in later stages. Fortunately, for most patients, their complications are not as severe.
"For most patients, unfortunately, their complications are not as late. Early warning signs include fever, fatigue, unexplained weight loss, and night sweats. As the disease advances, patients may feel pain in their limbs during movement, medically known as claudication, caused by reduced blood flow," says Dr Ekwom.
"If it's affecting your arms, you work with them and notice that they are getting tired and painful. Pain can also occur directly over the affected vessels, such as in the neck or arms. If blood vessels leading to the brain narrow, patients may experience dizziness, headaches, or vision changes. Another simple symptom that can be noted is the variability of blood pressure. When someone's blood pressure is taken between one arm and the other, there could be a difference in the pressure. If the arteries supplying the kidneys are affected, patients can also develop high blood pressure through that route," he explains.
He adds that the disease can affect vessels throughout the body, including the carotid arteries feeding the brain, the aorta near the heart, vessels in the abdomen, and those supplying the lower limbs. In some patients, it triggers strokes. In others, it disrupts the heart's electrical activity or affects breathing.
“We have patients who have died from the disease even here in Kenya. The reason for death is usually the vascular complication, like stroke. In some patients it affects the heart, and then you get abnormal electrical activity of the heart, which can then affect how the heart is functioning."
Diagnosing the disease typically requires a combination of blood tests, which pick up markers of inflammation, and imaging scans like CT or MR angiograms, which allow doctors to examine the walls of blood vessels directly rather than simply checking blood flow. Dr Ekwom explains that raising public awareness of the condition matters precisely because it is so easily missed.
