Fatigue

History of present illness includes open-ended questions about what "fatigue" is, listening for descriptions that could suggest dyspnea on exertion, somnolence, or muscle weakness. The relationships between fatigue, activity, rest, and sleep should be elicited, as should the onset, time course and pattern, and factors that increase or decrease fatigue.

Review of systems should be thorough because potential causes of fatigue are so numerous and diverse. Among important nonspecific symptoms are fever, weight loss, and night sweats (possibly suggesting cancer, a rheumatologic disorder, or an infection). Menstrual history is obtained in women of child-bearing age. Unless a cause is evident, patients should be asked questions from screening questionnaires for psychologic disorders (eg, depression, anxiety, drug use disorder, somatoform disorders, domestic violence).

Past medical history should address known disorders. Complete drug use history should include prescription, over-the-counter, and recreational drugs.

Social history should elicit descriptions of diet, drug use, and the effect of fatigue on quality of life, employment, and social and family relationships.

Vital signs are checked for fever, tachycardia, tachypnea, and hypotension.

General examination should be particularly comprehensive, including general appearance and examination of the heart, lungs, abdomen, head and neck, breasts, rectum (including prostate exam and testing for occult blood), genitals, liver, spleen, lymph nodes, joints, and skin.

Neurologic examination should include testing of, at a minimum, mental status, cranial nerves, mood, affect, strength, muscle bulk and tone, reflexes, and gait.

Usually if fatigue is of recent onset, a more focused examination will reveal the cause. If fatigue is chronic, examination is unlikely to reveal a cause; however, thorough physical examination is an important way to build rapport with the patient and occasionally is diagnostically helpful.

In general, a cause is more likely to be found when fatigue is one of many symptoms than when fatigue is the sole symptom. Fatigue that worsens with activity and lessens with rest suggests a physical disorder. Fatigue that is present constantly and does not lessen with rest, particularly with occasional bursts of energy, may indicate a psychologic disorder.

In the absence of red flag findings, a thorough history, physical examination, and routine laboratory testing (plus tests directed at specific findings—see ) should suffice for an initial evaluation. If test results are negative, watchful waiting is usually appropriate; if fatigue worsens or other symptoms and signs develop, the patient is reevaluated.

Several causes can be considered for patients with prolonged or chronic fatigue and selected other common or specific clinical findings.

Testing is directed at causes suspected based on clinical findings. If no cause is evident or suspected based on clinical findings, laboratory testing is unlikely to reveal a cause. Still, many clinicians recommend testing with the following:

Creatine kinase (CK) is recommended if muscle pain or weakness is present. HIV testing and testing for tuberculosis with purified protein derivative (PPD) placement or interferon-gamma release assays Diagnosis Tuberculosis is a chronic, progressive mycobacterial infection, often with an asymptomatic latent period following initial infection. Tuberculosis most commonly affects the lungs. Symptoms include... read more are recommended if the patient has risk factors. Chest x-ray is recommended if cough Cough in Adults Cough is a protective reflex that prevents aspiration and expels particles and irritants from the airway. However, it can become uncontrolled or disabling and is one of the most common symptoms... read more or dyspnea Dyspnea Dyspnea is unpleasant or uncomfortable breathing. It is experienced and described differently by patients depending on the cause. Although dyspnea is a relatively common problem, the pathophysiology... read more is present. Other testing, such as for infections or immunologic deficiencies, is not recommended unless there are suggestive clinical findings.

Diagnosis of myalgic encephalomyelitis/systemic exertion intolerance disease/chronic fatigue syndrome Chronic Fatigue Syndrome Chronic fatigue syndrome (CFS, also called myalgic encephalomyelitis/chronic fatigue syndrome [ME/CFS]) is a syndrome of life-altering fatigue lasting > 6 months that is unexplained and is accompanied... read more requires specific diagnostic criteria Diagnosis Chronic fatigue syndrome (CFS, also called myalgic encephalomyelitis/chronic fatigue syndrome [ME/CFS]) is a syndrome of life-altering fatigue lasting > 6 months that is unexplained and is accompanied... read more .