A General Practitioner who sees 25 patients per day may see perhaps two patients a week complaining of fatigue. Often, patients come in runs of three: so three or more people a week complaining of fatigue is not uncommon. Usually, the patient will say “I am feeling so tired lately”.
This rejoinder to “How are you feeling?” opens a proverbial Pandora’s box of possibilities. This is where a simple but systematic approach holds you in good stead. In which case, the aetiological approach suggested by Adjunct Professor Murtagh appeals.
Probable causes
- Stress / anxiety
- Depression
- Viral (or post-viral) — e.g. Glandular Fever
- Sleep-related Disorder — e.g. OSA
Serious disorders (red flags)
- Malignancy
- Cardiac Arrhythmia (e.g. SSS) or Cardiomyopathy
- Anaemia
- Infections — HIV, Hepatitis C, Hepatitis B
- Haemochromatosis
Pitfalls
- Masked depression — thyroid
- Coeliac disease
- Food intolerance
- Incipient CCF
- Fibromyalgia
- Deconditioning
- Drugs — alcohol, prescribed, withdrawal
Once you have completed also a systematic review, consider the following tests.
Investigations
- FBC & film
- ESR (CRP)
- ECG +/- Holter
- TSH
- LFTs
- RFTs + Ca, Mg
- BSL
- MSU
Other investigations to consider:
- Plasma cortisol
- Iron studies
- Autoimmune antibodies — ANA, RF
- HIV Ab
- CXR +/- spirometry
- Chronic infection screen — Hepatitis A–E (exposure), CMV (immunosuppressed), EBV (young), RRV (QLD), Lyme (bush), Brucellosis (abbatoire, farmer), Q fever (abbatoire, farmer), TB (immigrant), Malaria (returned traveller), SBE (valvular heart disease), toxoplasmosis (pregnant, immunosuppressed)
- Neuromuscular disorders — muscle enzyme assay, EMG
- Sleep Study
References
- Fatigue – a rational approach to investigation, Jessica Wilson – Australian Family Physician Vol. 43, No. 7. July 2014
- Fatigue – a general diagnostic approach, A/P John Murtagh – Australian Family Physician Vol. 32, No. 11. November 2003