Still’s disease, also known as adult-onset Still’s disease (AOSD) or systemic juvenile idiopathic arthritis (in children), is a rare inflammatory disorder characterized by high fevers, rash, and joint pain. While the disease itself can be challenging to diagnose and manage, its complications can be serious and affect multiple organ systems, sometimes leading to long-term disability or life-threatening conditions.
One of the primary complications of Still’s disease involves the **joints**. Although arthritis is a hallmark symptom, about a quarter of patients may not have joint involvement at the onset, and some may never develop it. For those who do, the arthritis can be severe, causing swelling, redness, warmth, and stiffness, especially after periods of rest. Over time, persistent inflammation can lead to **joint erosion and damage**, which may result in chronic pain, reduced mobility, and deformities. This joint damage can significantly impair quality of life if not adequately controlled.
Still’s disease can also cause **organ involvement** beyond the joints. Enlargement of lymph nodes (lymphadenopathy), liver (hepatomegaly), and spleen (splenomegaly) is common. Inflammation can affect the lungs, causing pleuritis (inflammation of the lining around the lungs), and the heart, leading to pericarditis (inflammation of the sac surrounding the heart) or myocarditis (inflammation of the heart muscle). These cardiac complications can be serious, potentially causing chest pain, arrhythmias, or heart failure if untreated. Inflammation may also involve the eyes and other serous tissues, potentially leading to discomfort and vision problems.
Gastrointestinal symptoms such as nausea, weight loss, poor appetite, and mouth ulcers (canker sores) can occur, reflecting systemic inflammation and its impact on the digestive tract.
The **central nervous system (CNS)** can be affected in some cases, leading to neurological complications like seizures or meningismus (symptoms resembling meningitis). Patients may also experience cognitive dysfunction, often described as “brain fog,” which is thought to result from inflammation within the brain triggered by the immune system’s abnormal response.
A particularly severe and potentially life-threatening complication is **macrophage activation syndrome (MAS)**. MAS is a hyperinflammatory state where the immune system becomes excessively activated, causing widespread inflammation and organ dysfunction. It can present with high fever, rash, enlarged liver and spleen, swollen lymph nodes, and cardiorespiratory problems. MAS requires urgent medical attention as it can rapidly progress to multi-organ failure.
Long-term use of corticosteroids, a common treatment for Still’s disease, can itself cause complications such as bone weakening (osteoporosis), compression fractures, and increased susceptibility to infections. These side effects highlight the importance of careful management and the use of steroid-sparing therapies when possible.
Other complications include **skin manifestations** beyond the classic salmon-pink rash. Some patients develop atypical rashes such as raised red or purple plaques, itchy bumps resembling eczema or hives, which can be distressing and may complicate diagnosis.
Growth disturbances can occur in children with systemic juvenile idiopathic arthritis (the pediatric form of Still’s disease). These include reduced overall growth rates, limb-length discrepancies due to uneven joint inflammation, and decreased bone density, all of which can impact physical development.
Infections may be more common due to both the disease’s immune dysregulation and immunosuppressive treatments. Patients need monitoring for signs of infection, especially respiratory infections.
In summary, Still’s disease complications span from joint destruction and organ inflammation to severe immune system overactivation and treatment-related side effects. These complications require vigilant monitoring and a multidisciplinary approach to treatment to minimize long-term damage and improve patient outcomes.
