From the Guidelines
A comprehensive workup for subjective fatigue should begin with a detailed history and physical examination to identify potential causes, as recommended by the American Society of Clinical Oncology 1 and the National Comprehensive Cancer Network 1.
Key Components of the Workup
- A focused fatigue history, including onset, pattern, duration, change over time, associated or alleviating factors, and interference with function 1
- Evaluation of disease status, including risk of recurrence and review of systems to determine if other symptoms substantiate suspicion for recurrence 1
- Assessment of treatable contributing factors, such as comorbidities, medications, alcohol/substance abuse, nutritional issues, weight/caloric intake changes, and deconditioning 1
- Laboratory tests, including complete blood count, comprehensive metabolic panel, thyroid function tests, inflammatory markers, fasting glucose, HbA1c, vitamin levels, and ferritin [@Example@]
- Additional tests, such as sleep study, cardiac evaluation, screening for depression and anxiety, infectious disease screening, autoimmune markers, cortisol levels, or specialized testing for chronic fatigue syndrome, depending on clinical suspicion [@Example@, 1]
Lifestyle Assessment
- Sleep habits, physical activity, nutrition, and stress levels should be assessed, as these factors frequently contribute to fatigue 1
- Patients should be educated on energy conservation, activity enhancement, and stress management techniques 1
Referral to Specialized Professionals
- Referral to an appropriately trained professional, such as a cardiologist, endocrinologist, mental health professional, or internist, may be necessary to manage specific contributing factors or comorbidities 1
From the Research
Comprehensive Workup for Subjective Fatigue
To approach a comprehensive workup for subjective fatigue, several factors and potential underlying causes must be considered.
- Thyroid Function: Abnormal thyroid functions have been associated with various systemic effects, including renal function alterations and electrolyte imbalances 2. Thus, assessing thyroid function through tests such as TSH, free T4, and free T3 can be crucial.
- Renal Function: Given the potential impact of thyroid dysfunction on renal function, evaluating renal function through tests like serum creatinine, eGFR, and uric acid may provide valuable insights into the patient's condition 2.
- Electrolyte Balance: Electrolyte imbalances, particularly alterations in serum sodium, can be associated with thyroid dysfunction and may contribute to fatigue 2. Therefore, assessing electrolyte levels is an important component of the workup.
- Anemia: Anemia is a common complication in patients with chronic kidney disease and can significantly contribute to fatigue 3. A complete blood count (CBC) to evaluate for anemia, and further testing to determine the cause of anemia, such as iron deficiency, is essential.
- Iron Deficiency: Iron deficiency often co-exists with anemia in patients with chronic kidney disease and correcting it can improve anemia and reduce the need for erythropoiesis-stimulating agents 3. Assessing iron stores through ferritin and transferrin saturation can help identify iron deficiency.
Additional Considerations
- A thorough medical history and physical examination to identify other potential causes of fatigue, such as sleep disorders, cardiovascular disease, or psychiatric conditions.
- Laboratory tests may include, but are not limited to, complete metabolic panels, liver function tests, and inflammatory markers to rule out other systemic diseases.
- The use of erythropoiesis-stimulating agents for anemia associated with chronic kidney disease should be considered judiciously, weighing the benefits against the risks 3.