This is an important study. There has long been a hypothesis that neuroinflammation plays a prominent role in chronic fatigue syndrome, usually called myalgic encephalomyelitis in Europe. Encephalomyelitis is the medical term for brain inflammation.
This imaging study confirms this inflammation and gives detail about which parts of the brain are affected. Levels of inflammation in subjects compared with controls were higher in cingulate cortex, hippocampus, amygdala, thalamus, midbrain, and pons were 45%–199% higher in CFS/ME patients than in healthy controls.
Not surprisingly, the regions affected correlate with symptoms:
amygdala, thalamus, and midbrain inflammation correlated with cognitive impairment (brain fog),
cingulate cortex and thalamus inflammation correlated with pain,
hippocampus involvement correlated with depression.
Integrative treatment approaches attempt to address this brain inflammation amongst other things.
Neuroinflammation in Patients with Chronic Fatigue Syndrome/Myalgic Encephalomyelitis: An 11C-(R)-PK11195 PET Study
Yasuhito Nakatomi1, Kei Mizuno, Akira Ishii, Yasuhiro Wada, Masaaki Tanaka, Shusaku Tazawa, Kayo Onoe, Sanae Fukuda, Joji Kawabe, Kazuhiro Takahashi, Yosky Kataoka, Susumu Shiomi, Kouzi Yamaguti, Masaaki Inaba1, Hirohiko Kuratsune and Yasuyoshi Watanabe
J Nucl Med 2014 jnumed.113.131045 published ahead of print March 24, 2014
Chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME) is a disease characterized by chronic, profound, disabling, and unexplained fatigue. Although it is hypothesized that brain inflammation is involved in the pathophysiology of CFS/ME, there is no direct evidence of neuroinflammation in patients with CFS/ME. Activation of microglia or astrocytes is related to neuroinflammation. 11C-(R)-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)-3-isoquinoline-carboxamide (11C-(R)-PK11195) is a ligand of PET for a translocator protein that is expressed by activated microglia or astrocytes. We used 11C-(R)-PK11195 and PET to investigate the existence of neuroinflammation in CFS/ME patients.
Methods: Nine CFS/ME patients and 10 healthy controls underwent 11C-(R)-PK11195 PET and completed questionnaires about fatigue, fatigue sensation, cognitive impairments, pain, and depression. To measure the density of translocator protein, nondisplaceable binding potential (BPND) values were determined using linear graphical analysis with the cerebellum as a reference region.
Results: The BPND values of 11C-(R)-PK11195 in the cingulate cortex, hippocampus, amygdala, thalamus, midbrain, and pons were 45%–199% higher in CFS/ME patients than in healthy controls. In CFS/ME patients, the BPND values of 11C-(R)-PK11195 in the amygdala, thalamus, and midbrain positively correlated with cognitive impairment score, the BPND values in the cingulate cortex and thalamus positively correlated with pain score, and the BPND value in the hippocampus positively correlated with depression score.
Conclusion: Neuroinflammation is present in widespread brain areas in CFS/ME patients and was associated with the severity of neuropsychologic symptoms. Evaluation of neuroinflammation in CFS/ME patients may be essential for understanding the core pathophysiology and for developing objective diagnostic criteria and effective medical treatments.