Investigating unexplained fatigue in general practice with a particular focus on CFS/ME

Unexplained fatigue is not infrequent in the community. It presents a number of challenges to the primary care physician and particularly if the clinical examination and routine investigations are normal. However, while fatigue is a feature of many common illnesses, it is the main problem in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME). This is a poorly understood condition that is accompanied by several additional symptoms which suggest a subtle multisystem dysfunction. Not infrequently it is complicated by sleep disturbance and alterations in attention, memory and mood. Specialised services for the diagnosis and management of CFS/ME are markedly deficient in the UK and indeed in virtually all countries around the world. However, unexplained fatigue and CFS/ME may be confidently diagnosed on the basis of specific clinical criteria combined with the normality of routine blood tests. The latter include those that assess inflammation, autoimmunity, endocrine dysfunction and gluten sensitivity. Early diagnosis and intervention in general practice will do much to reduce patient anxiety, encourage improvement and prevent expensive unnecessary investigations. There is presently an on-going debate as to the precise criteria that best confirms CFS/ME to the exclusion of other medical and psychiatric/psychological causes of chronic fatigue. There is also some disagreement as to best means of investigating and managing this very challenging condition. Uncertainty here can contribute to patient stress which in some individuals can perpetuate and aggravate symptoms. A simple clinical scoring system and a short list of routine investigations should help discriminate CFS/ME from other causes of continued fatigue.