A reader posted a comment on AHCC. He reported improvement from it and add it to his other rotating antimicrobials.
“Antimicrobials were wormwood, black walnut, olive leaf extract, curcumin, turmeric/piperine, monolaurin, thyme, oregano oil, Pau D’Arco, neem, caprylic acid, boswellia and now AHCC. Most I have done a couple of rotations. I may have forgotten one or two. In the early days I did one at a time, but later on did two at a time.”
Ken did a post a few months ago on amino acids. I have benefited from supplementing them as well.” – Reader
I was curious on what it is known about AHCC.
- “Active hexose correlated compound (AHCC) is a product prepared from the mycelium of edible Basidiomycete fungi that contains oligosaccharides…rats treated with AHCC had higher aerobic and lactic acid bacteria counts as well as higher bifidobacteria counts, whereas clostridia were reduced when compared with the TNBS group. ” 
- Active hexose-correlated compound and Bifidobacterium longum BB536 exert symbiotic effects in experimental colitis.
- “the oral treatment with AHCC protected mice from lethal infection with Pseudomonas aeruginosa and intraperitoneal one also protected mice from infection with methicillin-resistant Staphylococcus aureus (MRSA).” 
- “ administration of AHCC… increased ability to clear bacteria. ” 
- “ AHCC may display a protective role against opportunistic fungal infection” 
- “suggest that AHCC protects mice in this model by restoring the immune and other systems negatively affected by trauma, infection, and food deprivation. ”  – which may also include mal-absorption.
- “AHCC appears to induce an early activation of the immune response, leading to an effective clearance of bacteria and rapid recovery.” 
- “Supplementation with AHCC appears to modulate immunity and increase survival in response to acute infection (including influenza virus, avian influenza virus, Klebsiella pneumoniae, Candida albicans, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus) and warrants further investigation.” 
- “Enhanced immune function observed with AHCC could be caused by attenuated concentrations of stress hormones and catecholamines.” 
AHCC looks very promising for CFS. It shifts bacteria in the right direction and kills off and clears many pathogens.