Tired all the time ( Fatigue ) : Initial workup

Commonly ordered tests in the evaluation of fatigue include full blood count, electrolyte panel, thyroid hormone panel, renal function test, liver function test, blood glucose, urinalysis, inflammatory markers, and urine pregnancy test in females of child-bearing age. However, studies have demonstrated that there is limited positive predictive value of these blood tests. Fatigue is associated with a low pre-test probability of underlying organic pathology, with results affecting management in only 5% of patients.

Given the low yield of investigations in elucidating an underlying cause for fatigue and the implications of false-positive results, it is reasonable to adopt an approach of watchful waiting in the absence of red flags and symptoms that point towards underlying pathology. This strategy reduces the number of unnecessary tests and the risk of false positives, which can lead to unnecessary anxiety and further invasive investigations. When the decision has been made to investigate, judicious selection of tests should be employed to ensure that they are clinically indicated and likely to impact patient management. This approach not only aligns with evidence-based practice but also fosters a more patient-centered and cost-effective healthcare delivery.