A. SREENIVASA REDDY (ABU DHABI)
A 34-year-old Abu Dhabi resident diagnosed with a rare autoimmune disease has recovered after doctors at Burjeel Hospital Abu Dhabi treated him with high-dose corticosteroid therapy.
The autoimmune disease, known as Adult-Onset Still’s Disease (AOSD), is a rare and difficult-to-diagnose condition that affects approximately one to four people in a million worldwide.
The patient, who had always enjoyed robust health, was suddenly hit by high-grade fever that persisted for more than two weeks. Despite multiple hospital visits and extensive routine testing, including blood cultures and standard infection screens, the cause of his illness remained unknown, the hospital said.
As his condition worsened, he developed disabling joint pain, extreme fatigue, intense inflammation and signs of liver involvement. Although he appeared stable, doctors at Burjeel Hospital Abu Dhabi were concerned that the persistent symptoms could point to a potentially life-threatening illness.
The medical team launched an in-depth investigation and ruled out infections, other autoimmune diseases and malignancies before arriving at the diagnosis of AOSD.
Dr Niyas Khalid, Specialist, Internal Medicine, who treated the patient along with Dr Abdul Hakeem Muhammed, Specialist, Internal Medicine, said AOSD is extremely difficult to diagnose because of its rarity and its resemblance to several serious diseases.
“It mimics many life-threatening diseases such as severe infections, autoimmune disorders, liver disease, and even cancer. It’s often under-recognised, particularly in regions where fever is commonly attributed to infectious causes,” Dr. Niyas told Aletihad.
Explaining the name of the condition, Dr Niyas said Adult-Onset Still’s Disease is named after Sir George Frederic Still, the British physician who first described a similar inflammatory disease in children more than a century ago. When the same pattern of illness was later recognised in adults, it became known as Adult-Onset Still’s Disease. The term “adult-onset” distinguishes it from the childhood form of the disease.
Dr. Niyas said AOSD is different from many classic autoimmune diseases such as lupus or rheumatoid arthritis because many of those diseases have specific antibodies that help confirm the diagnosis. In AOSD, autoimmune tests are often negative, making the condition harder to identify.
“In this patient, extensive testing for autoimmune diseases, infections, and even malignancies was negative. The diagnosis emerged not from a single positive test but from recognising a characteristic pattern of symptoms, laboratory abnormalities, and the exclusion of other conditions,” Dr. Niyas said.
He said AOSD is a diagnosis that relies heavily on clinical judgment and experience. In this case, one major diagnostic clue was an extremely high ferritin level. Ferritin is a protein that stores iron in the body, but it also rises sharply when the immune system is highly activated.
Dr Niyas said ferritin levels in healthy adults typically range between 30 and 400 ng/mL, depending on age and sex. In this patient, the ferritin level was 6,900 ng/mL, more than 15 times the upper limit of normal.
“Such extreme elevations are uncommon and immediately signal that something unusual is happening within the immune system,” Dr Niyas said.
He said elevated ferritin can occur in infections, liver disease and some cancers, but levels in the thousands are particularly characteristic of a small group of inflammatory conditions, including AOSD. After tests failed to identify infection, another autoimmune disease or malignancy, the combination of persistent fever, severe inflammation, liver involvement and a ferritin level of 6,900 ng/mL became a crucial clue.
When affected by AOSD, the patient’s immune system becomes overactive and attacks the body, causing widespread inflammation. If not diagnosed and treated in time, it can lead to severe complications such as organ damage, chronic inflammatory arthritis, liver failure or a potentially fatal immune storm.
For the patient, the illness was physically and emotionally draining.
“During those days, I shivered from fever and struggled to get up from bed, lift my hands, and move my body. There was no appetite because of throat pain. Despite taking medicine, my fever recurred, draining me emotionally. I prayed to God to give my routine life back,” the patient recalled.
Once AOSD was suspected, doctors started high-dose corticosteroid therapy, which is considered the cornerstone treatment for the condition. After the initial high doses, the steroid was tapered carefully over several weeks to suppress the immune reaction while allowing safe recovery.
The response was rapid.
“Within 24 hours, the fever subsided. Within 48 hours, the patient felt significantly better, with improvement in joint pain and energy levels. Laboratory markers improved in parallel,” Dr Niyas said.
“Once treatment was started, the ferritin level rapidly declined alongside the patient’s symptoms,” Dr Niyas said.
The patient also began to regain movement and confidence.
“I am so happy that I can move my body without support for the first time after a while. Everyone in the hospital gave me hope whenever I doubted, got frustrated, and questioned myself,” the patient said.
Doctors said the patient has recovered remarkably well, but ongoing follow-up remains essential because AOSD can recur in some patients. He will continue regular follow-up with internal medicine and rheumatology specialists to monitor for any signs of relapse and ensure long-term stability.