A.Post exertional neuroimmune exhaustion (PENEpen-e):Compulsory
This cardinal feature is a pathological inability to produce sufficient energy on demand with prominent symptoms primarily in
the neuroimmune regions. Characteristics are as follows:
1. Marked, rapid physical and ? or cognitive fatigability in response to exertion,which may be minimal such as activities
of daily living or simple mental tasks, can be debilitating and cause a relapse.
2. Post exertional symptom exacerbation: e.g. acuteflu-like symptoms,pain and worsening of other symptoms.
3. Postexertional exhaustion may occur mmediately after activity or be delayed by hours or days.
4. Recovery period is prolonged,usually taking 24 h or longer. A relapse can last days,weeks or longer.
5. Low threshold of physical and mental fatigability (lack of stamina) results in a substantial reduction in pre-illness
activity level.