Ten (of 75) young patients had neurologic findings such as febrile seizures, single generalized seizures, mild ataxia, and muscular hypotonia with retarded motor development, but magnetic resonance imaging detected unilateral and bilateral T2-hyperintensive white-matter lesions in 15 patients (20%)

According to recent studies, calcifications of channels seen in dementia can also occur in specific brain areas such as the visual complex in the occipital lobe. Such calcium channel blockages can cause visual problems or partial field hallucinations (Paroxysmal visual manifestations). Other papers show a link between migraine, visual aura and cerebral calcifications. Disturbances may be followed by

convulsions and associated with gastrointestinal phenomena.

Pain, which can vary in severity, is a common symptom in virtually all types of arthritis. Other symptoms include swelling, joint stiffness and aching around the joint(s). Arthritic disorders like lupus and rheumatoid arthritis can affect other organs in the body, leading to a variety of symptoms. Symptoms may include:

- Inability to use the hand or walk

- Stiffness, which may be worse in the morning, or after use

- Malaise and fatigue

- Weight loss

- Poor sleep

- Muscle aches and pains

- Tenderness

- Difficulty moving the joint

It is common in advanced arthritis for significant secondary changes to occur. For example, arthritic symptoms might make it difficult for a person to move around and/or exercise, which can lead to secondary effects, such as:

- Muscle weakness

- Loss of flexibility

- Decreased aerobic fitness

These changes, in addition to the primary symptoms, can have a huge impact on quality of life.

There are several diseases where joint pain is primary, and is considered the main feature. Generally when a person has "arthritis" it means that they have one of these diseases, which include:

- Osteoarthritis

- Rheumatoid arthritis

- Gout and pseudo-gout

- Septic arthritis

- Ankylosing spondylitis

- Juvenile idiopathic arthritis

- Still's disease

Joint pain can also be a symptom of other diseases. In this case, the arthritis is considered to be secondary to the main disease; these include:

- Psoriasis (Psoriatic arthritis)

- Reactive arthritis

- Ehlers-Danlos Syndrome

- Haemochromatosis

- Hepatitis

- Lyme disease

- Sjogren's disease

- Hashimoto's thyroiditis

- Celiac disease

- Non-celiac gluten sensitivity

- Inflammatory bowel disease (including Crohn's disease and ulcerative colitis)

- Henoch–Schönlein purpura

- Hyperimmunoglobulinemia D with recurrent fever

- Sarcoidosis

- Whipple's disease

- TNF receptor associated periodic syndrome

- Granulomatosis with polyangiitis (and many other vasculitis syndromes)

- Familial Mediterranean fever

- Systemic lupus erythematosus

An "undifferentiated arthritis" is an arthritis that does not fit into well-known clinical disease categories, possibly being an early stage of a definite rheumatic disease.