special subjects
Fatigue
Evaluation of Fatigue
Fatigue can be highly subjective. Patients vary in what they consider to be fatigue and how they describe it. There are also few ways to objectively confirm fatigue or tell how severe it is. History and physical examination focus on identifying subtle manifestations of underlying illness (particularly infections, endocrine and rheumatologic disorders, anemia, and depression) that can be used to guide testing. History of present illnessincludes 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 systemsshould 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 historyshould address known disorders. Complete drug use history should include prescription, over-the-counter, and recreational drugs. Social historyshould 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. Chronic weight loss Chronic fever or night sweats Generalized lymphadenopathy Muscle weakness or pain Serious nonfatigue symptoms (eg, hemoptysis, hematemesis, severe dyspnea, ascites, confusion, suicidal ideation) Involvement of > 1 organ system (eg, rash plus arthritis) New or different headache or loss of vision, particularly with muscle pains, in an older adult 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: Complete blood count (CBC) Ferritin Erythrocyte sedimentation rate (ESR) Thyroid-stimulating hormone (TSH) Chemistries, including electrolytes, glucose, calcium, and renal and liver tests 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 Diagnosis are recommended if the patient has risk factors. Chest x-ray is recommended if Diagnosis of Chronic Fatigue Syndrome requires 