Fatigue is a common presenting symptom, particularly in primary care. However, the cause may not be immediately apparent because fatigue is a nonspecific symptom. Therefore, the key to making a diagnosis is taking a careful and detailed history, followed by an appropriate physical examination and limited laboratory testing.
Although fatigue can be a symptom of almost any illness, the disorders listed here are those characterized almost exclusively by fatigue as a predominant symptom.
(list not exhaustive)
- Substance use disorder
- Idiopathic chronic fatigue
- Chronic fatigue syndrome
- Other disease categories associated with fatigue
- Endocrine and metabolic
- Infectious and postinfectious (e.g., long COVID)
- Connective tissue disorders
- Sleep disturbances (e.g., shift work)
Given a patient with fatigue, the candidate will perform a thorough and complete history and physical examination to establish an underlying cause.
Given a patient with fatigue, the candidate will
- list and interpret critical clinical findings, including
- features that are more likely associated with either a psychological or iatrogenic cause of fatigue; and
- results of a complete physical examination;
- critically select and interpret clinical investigations, recognizing that in the absence of localizing features, tests may be of limited value; and
- construct an effective initial management plan, including
- treating any underlying causes; and
- outlining a plan of management that will help minimize the effect of fatigue on function and quality of life if no underlying cause can be identified.