The Fukuda 1994 definition of CFS ‘nets’ a wide range of patients, yet it remains the most widely recognised definition, particularly in the US, and has been used in the great majority of published research studies. Prof Ben Natelson at the Beth Israel Medical Centre has been at the forefront of work to ‘subgroup’ CFS patients on the basis of clinical or objective measurements, and his new review in ‘Frontiers in Physiology’  gives an overview of this research in the past two decades. Overall, his working hypothesis is that there is a subgroup of CFS patients with an “underlying neurological disease which leads to the symptoms of fatigue and cognitive dysfunction”. And he has 2 two main hypotheses about how this might occur: one involves oxidative stress, which compromises membrane and cell function, while the other involves the orthostatic intolerance seen in about 25% of CFS patients.

This review is a rarity in ME/CFS – a summary of 20 years of experimental work conducted in a step-by-step progression by a dedicated team. Such ‘programs’ of research are a vital if scientific understanding is to progress, and there should be many more of them across the world.

Reference: Brain dysfunction as one cause of CFS symptoms including
difficulty with attention and concentration. Natelson BH. Front Physiol 2013; 4: 109.