Mixed connective tissue disease

Summary

Mixed connective tissue disease (MCTD) has signs and symptoms of a combination of disorders — primarily lupus, scleroderma, and polymyositis. Many people with this uncommon disease also have Sjogren's syndrome. For this reason, MCTD is sometimes called 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 over a number of years, which can complicate diagnosis.

Early signs and symptoms often involve the hands. Fingers might get puffy, and the fingertips become white and numb, often in response to cold exposure. In later stages, some organs — such as the lungs, heart and kidneys — can be affected.

There's no cure for mixed connective tissue disease. Treatment depends on how severe the disease is and the organs involved.

(Autoimmune Association, 2023)

MCTD develops as RNP (ribonucleoprotein) molecules are attacked by antibodies, inhibiting the production of messenger RNA. The body’s fibers that help to establish its framework and physical support (connective tissues) are also attacked.

Often referred to as an overlap disease, MCTD presents with signs and symptoms that can also look like several other conditions (including lupus, scleroderma, and polymyositis). It is a disease that presents different symptoms of different diseases over the course of several years but typically afflicts the hands early on. 

(Global Autoimmune Institute, 2023)

Symptoms

Early indications of mixed connective tissue disease can include:

• General feeling of being unwell. This can include increased fatigue and a mild fever.

• Cold and numb fingers or toes (Raynaud's phenomenon). In response to cold or stress, your fingers or toes might turn white and then purplish blue. After warming, the fingers or toes turn red.

• Swollen fingers or hands. Some people have swelling of the fingers.

• Muscle and joint pain. Joints can become inflamed, swollen and deformed, similar to what occurs with rheumatoid arthritis.

• Rash. Red or reddish brown patches can appear over the knuckles.

(Autoimmune Association, 2023)

Red/reddish-brown rash patches over the knuckles, increased fatigue/mild fever, Raynaud’s phenomenon (cold/numb fingers/toes), swelling of the fingers or hands, muscle and joint pain/swelling/deformities, organs (kidneys, heart, and lungs) can be afflicted later in the progression of the disease, chest pain, stomach inflammation, dyspnea (trouble with breathing), high erythrocyte sedimentation rate, and dry mouth/eyes.

(Global Autoimmune Institute, 2023)

Diagnostic Criteria

Under Investigation

Study Classification Criteria

Under Investigation

Diagnostic Tests

Under Investigation

Organized Autoimmunity

(Alternative Autoimmune Disease Classification: FIEM, MIEM or BIEM, or FEM, MEM or BEM)

1. sex predominance (is an autoimmune disease primarily found in genetic Females, Males, or equally in Both?)

   1. Under Investigation

2. Inherited and acquired gene variations that cause increased susceptibility

   1. Human Leukocyte Antigen (HLA) Associations

      1. Under Investigation

   2. Other Gene Variations (mutations)

      1. Under Investigation

3. Gene Triggering Environmental Exposures

   1. Infections

      1. COVID-19 (Chang et. al, 2023, found a significantly higher risk of Mixed connective tissue disease following COVID-19 infection in a study of 3,814,479 participants)

   2. Toxins

      1. Under Investigation

   3. Stress

      1. Needs to be assessed for each patient

4. Multiple interactive and destructive immune system pathologies

   1. Under Investigation

Tissue-Type or Cell-Type Attacked

Under Investigation

Treatment(s)

Under Investigation

Managing Specialist(s)

Under Investigation

Research Authors

Under Investigation

Research Institutions

Under Investigation

Average Time from Symptom Onset to Diagnosis

Under Investigation

Last Updated

September 05, 2023

References

Chang R, Yen-Ting Chen T, Wang SI, Hung YM, Chen HY, Wei CJ. Risk of autoimmune diseases in patients with COVID-19: A retrospective cohort study. EClinicalMedicine. 2023 Feb;56:101783. doi: 10.1016/j.eclinm.2022.101783. Epub 2023 Jan 10. PMID: 36643619; PMCID: PMC9830133.

Mixed connective tissue disease. Autoimmune Association. (2023, April 20). Retrieved September 05, 2023 from https://autoimmune.org/disease-information/mixed-connective-tissue-disease-mctd/

MIXED CONNECTIVE TISSUE DISEASE. Global Autoimmune Institute. (2023). Retrieved September 05, 2023 from https://www.autoimmuneinstitute.org/autoimmune-resources/autoimmune-diseases-list/mixed-connective-tissue-disease/