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

Abstract

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.

The presence of overlapping quality of life symptoms in primary antibody deficiency (PAD) and chronic fatigue syndrome (CFS)

“…We have noted that many of our patients with PAD have significant chronic fatigue which adversely impacts their mental and physical health, as well as their daily living. The fatigue has similarities to that seen in our patients with CFS-particularly the delayed postexertional malaise that characterises CFS [23]. Our earlier unpublished work between 2002 and 2006 had shown fatigue and mood disturbance to be frequent in those with PAD and unrelated to frequent infections or lung damage.…”

“…However, this would be of insufficient severity to produce recurrent pneumonia, sinusitis, meningitis etc. and routine tests of immune function are almost invariably normal [23].…”

“…This utilises a scoring system for confirming the diagnosis of CFS in patients presenting with chronic fatigue without an underlying physical and mental cause ( Table 1). A score of 8 or more out of 13 for the core symptoms of CFS in the presence of normal blood tests for haematological, endocrine, renal, hepatic and immune abnormalities and with negative tests for inflammation, gluten sensitivity and autoimmunity was highly suggestive/diagnostic of CFS [23]. This scoring system was applied to the fatigue questionnaire used in the present survey to see how many patients within our cohort fulfilled our diagnostic criteria for CFS.…”

Infection Elicited Autoimmunity and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: An Explanatory Model

“…The comorbidity between ME/CFS and better studied autoimmune disorders such as SS ( 250 ), SLE, and multiple sclerosis ( 251 ) is an indication of this. Fatigability, which may or may not be related to the PEM of ME/CFS ( 252 – 255 ), occurs as a major symptom in some autoimmune ( 6 , 184 , 256 – 261 ), mitochondrial ( 262 , 263 ) and infectious ( 264 ) diseases. Immunostimulation, e.g., with Staphylococcal vaccine, theoretically could induce tolerance to autoepitopes involved in ME/CFS pathogenesis ( 265 – 267 ).…”

Controversy over exercise therapy for chronic fatigue syndrome: Key lessons for clinicians and academics

“…The diagnosis is difficult because there are many medical conditions that cause fatigue and many of them are obscure. Not all medical investigations are offered promptly to patients believed to have CFS (Bansal 2016). Furthermore, the nature of the fatigue is rarely, if ever, illness specific.…”