Chapter Two, Course WB1032
Differential Diagnosis and Exclusionary Conditions
As mentioned previously, patients with chronically fatiguing illness should be carefully evaluated medically and psychiatrically both early in the diagnostic process and throughout their care. Many diseases present similarly to CFS, and these must receive appropriate evaluation and treatment before considering CFS as a diagnosis. Examples include:1) conditions discovered during evaluation (e.g., effects of medications or dietary supplements, sleep disorders, untreated hypothyroidism, diabetes, infection, hypertension, menopause, obesity); 2) conditions that resolve on their own (e.g., pregnancy, recent surgery); and 3) chronic diseases whose resolution may be unclear for some time (e.g., myocardial infarction, heart failure).
Other medical diseases exclude the diagnosis of CFS in research studies and include: 1) organ failure (e.g., emphysema, cirrhosis, renal disease, cardiac diseases); 2) chronic infections (e.g., AIDS, hepatitis B or C); 3) rheumatic and chronic inflammatory diseases (e.g., systemic lupus erythematosus, rheumatoid arthritis, inflammatory bowel disease, chronic pancreatitis); 4) major neurological diseases (e.g., multiple sclerosis, neuromuscular diseases, epilepsy, stroke, head injury); 5) major endocrine diseases (e.g., adrenal insufficiency, hypopituitarism); 6) cancer and 7) primary sleep disorders (e.g., sleep apnea, narcolepsy).
Note that these conditions are considered exclusionary only in the research setting to ensure that patients in research studies have no known underlying diseases. In clinical practice, patients with the conditions mentioned above (and many others) may describe the same constellation of symptoms. The clinical professional must exercise care and judgment to assess the contribution of known diseases to the symptoms reported by the patient and could use the above exclusionary conditions as a guide. During a careful medical evaluation, CFS can be considered as a ‘working’ or tentative diagnosis so that appropriate treatment for symptoms may begin during the diagnostic process (Reeves et al., 2003).
Health care professionals caring for patients with CFS should also consider the possibility of an underlying or comorbid psychiatric condition. Several psychiatric disorders exclude the diagnosis of CFS and include lifetime occurrence of bipolar affective disorders, schizophrenia of any subtype, delusional disorders of any subtype, dementias of any subtype and organic brain disorders. Melancholic depression, alcohol or substance abuse, anorexia nervosa or bulimia are not necessarily exclusionary conditions; a thorough clinical evaluation must be completed to ensure that the illness has resolved before considering CFS.
Content Source: National Center for Zoonotic, Vector-Borne, and Enteric Diseases (ZVED)