Chronic heart disease:
- The fatigue in CHD is worse on exertion, but improves at rest. However, in advanced CHD, the fatigue may be continuous and even at rest.
- Investigations such as 2D Echocardiography will show that the pumping capacity of the heart is significantly reduced.
Connective tissue disorders:
- These are disorders involving the supportive protein-rich tissues that support the various organs and parts of the body.
- They are diagnosed on the basis of detailed history and physical examination supported with specific blood tests and diagnostic imaging.
Chronic Anemia:
- The fatigue in anemia is due to decreased oxygen carrying capacity of the blood due to abnormally low hemoglobin levels.
- A simple blood count can diagnose anemia.
Malignancy:
- Malignancy can also lead to severe fatigue and other symptoms similar to CFS.
- However, proper history and physical examination along with blood investigations, diagnostic imaging, and other specific tests help detect or rule out malignancies.
Chronic infections:
- They can also cause chronic fatigue; however, a specific infectious diagnosis and causative organisms can be detected with detailed history and physical examination along with other diagnostic tests.
Psychiatric illness:
- Many psychiatric illnesses have symptoms similar to chronic fatigue, especially mood disorders
- Therefore, a psychiatric screening and if required a thorough psychiatric evaluation may be necessary to rule out psychiatric illnesses.
Sleep disorders:
- Sleep disorders are very likely to produce chronic fatigue.
- A specific history along with a string of diagnostic tests in the sleep laboratory can confirm or rule out sleep disorders.
Drug or Substance Abuse:
- Chronic drug or substance abuse can also produce profound fatigue.
- A careful history and physical examination along with screening for drugs or other substances can confirm or rule out drug or substance abuse.
