Viral infection is a significant risk factor for CFS, with one study finding 22% of people with EBV experience fatigue six months later, and 9% having strictly defined CFS. A systematic review found that fatigue severity was the main predictor of prognosis in CFS, and did not identify psychological factors linked to prognosis.Another review found that risk factors for developing CFS after mononucleosis, dengue fever, or Q-fever included longer bed-rest during the illness, poorer pre-illness physical fitness, attributing symptoms to physical illness, belief that a long recovery time is needed, as well as pre-infection distress and fatigue. The same review found biological factors such as CD4 and CD8 activation and liver inflammation are predictors of sub-acute fatigue but not CFS. However, these findings are not generally accepted due to the use of the Oxford criteria in selecting patients. The CDC does not recognize attribution of symptoms as a risk factor.A study comparing diagnostic labels found that people labelled with ME had the worst prognosis, while those with PVFS had the best. Whether this is due to those with more severe or longer-lasting symptoms results in a label with the description of ME, or if being labelled with ME adversely causes a more severe or prolonged illness is unclear. Pathophysiology
Neurological
A range of neurological structural and functional abnormalities is found in people with CFS, including lowered metabolism at the brain stem and reduced blood flow to areas of the brain; these differences are consistent with neurological illness, but not depression or psychological illness.
Identifying the pain during a pressure change is a diagnostic indicator for the clinician. Treatment involves removing the void space by carefully replacing the offending restoration, repeating the endodontic treatment or removing the tooth. See also
Barotrauma – Injury caused by pressure
Dental trauma
List of diving hazards and precautions – Hazards associated with underwater diving
Toothache – Medical condition of the teeth

References


== External links ==