Like any complex long term disease, scleroderma in its various forms can take time to develop and so there will be individuals where some symptoms that may indicate early scleroderma (such as Raynaud's phenomenon) but not enough to make a definite diagnosis (of scleroderma).
Undifferentiated connective tissue disease
Undifferentiated connective tissue disease is a condition that affects the joints and muscles of the body. A disorder is classified as undifferentiated connective tissue disease when it cannot be classified as another type of connective tissue disease, such as scleroderma, rheumatoid arthritis or lupus. Symptoms of undifferentiated connective tissue disease may vary but include constriction of the blood vessels in the hands and feet, especially in response to cold (Raynaud phenomenon), sensitivity to light, joint pain (arthralgia), muscle weakness, and dryness in the eyes and mouth. Diagnosis of undifferentiated connective tissue disease can be obtained through blood tests and imaging (CT scan) of the chest. Treatment can include non-steroidal anti-inflammatory drugs (NSAIDs) and avoiding exposure to extreme temperatures.
An autoimmune disease can be an undifferentiated connective tissue disease. An autoimmune disease is where the system of the body that is responsible for protection from infection (immune system) is attacking the body itself. The cause of most autoimmune diseases is unknown, but is thought to include both environmental and genetic factors.
Mixed connective tissue disease
Mixed connective tissue disease has signs and symptoms of a combination of disorders — primarily lupus, scleroderma and polymyositis. For this reason, mixed connective tissue disease is sometimes referred to as an overlap disease.
In mixed connective tissue disease, the symptoms of the separate diseases usually don't appear all at once. Instead, they tend to occur in sequence over a number of years, which can make diagnosis more complicated.
Early signs and symptoms often involve the hands. Fingers might swell like sausages, and the fingertips become white and numb. In later stages, some organs — such as the lungs, heart and kidneys — may be affected.
There's no cure for mixed connective tissue disease.