P De Becker , J Nijs , N McGregor , K De Meirleir 
Dept. of Human Physiology,
Vrije Universiteit Brussel,
Collaborative Pain Research Unit
Department of Biological Sciences
Faculty of Science
University of Newcastle
Callaghan, New South Wales, Australia
The Holmes and Fukuda criteria are widely used criteria all over the world, yet a specific European study regarding CFS patient symptomatology has not been conducted so far.
This study was performed in an outpatient tertiary care setting fatigue clinic in Brussels. 2073 consecutive patients with major complaints of prolonged fatigue participated in the study. Multi-variate analyses were performed to assess the symptom presentation within a fatigued population and the differences between the Fukuda and Holmes definitions compared with an excluded chronic fatigued group in a large cohort of fatigued patients.
Of the 2073 patients complaining of chronic fatigue, 1578 CFS patients fulfilling the Fukuda criteria (100% of CFS group) and 951 (60.3% of the CFS group) fulfilled the Holmes criteria. Discriminant function analysis revealed that the Fukuda and Holmes definitions can be differentiated by symptom severity and prevalence. The Holmes definition was more strongly associated than the Fukuda definition with the symptoms that differentiated the CFS patients from the patients that did not comply with the CFS definitions. The inclusion of ten additional symptoms was found to improve the sensitivity/ specificity and accuracy for selection of CFS patients.
The CFS patients fulfilling the Holmes criteria have an increased symptom prevalence and severity of many of the symptoms that determine the difference between CFS and CF patients. Patients fulfilling the Fukuda criteria were less severely affected patients which leads to an increase in clinical heterogeneity.
We can conclude that the use of the Holmes criteria defining symptoms of fatigue, swollen/tender lymph nodes, sore throat, muscle weakness, recurrent flu-like symptoms, postexertional fatgigue, myalgia, memory disturbance, nonrestorative sleep with addition of certain symptoms (hot flushes instead of low-grade fever, attention deficit, paralysis, new sensitivities to food/drugs, difficulties with words, urinary frequency, cold extremities, photophobia, muscle fasciculations, lightheadedness, exertional dyspnea and gastrointestinal distrurbance) to the Holmes definition and removal of others (arthralgia and low-grade fever) would strengthen the ability to select CFS patients, also the incorporation of a severity index would be beneficial for subcategorization patients.