Out of all the theories of POIS, I have spent the most time considering the possibility of an allergic reaction to sperm. After much consideration, I believe it is possible, but very unlikely and not the cause of POIS. The body does create an antibody to sperm, recognizing it as a pathogen, and does cause polyclonal B cell activation (typically seen in autoimmune diseases) creating antibody clones for approximately 18 epitopes on sperm. The specific antibody made varies among people, and some do cross react with other epitopes in the body. "However, there is no association between chronic inflammatory or infectious diseases of the male reproductive tract and the presence of antisperm antibody in semen." (PMID: 18715698)
Therefore I believe the much simpler explanation for POIS is a long term infection of the prostate, known as chronic bacterial prostatitis. This is a rare but widely recognized problem in urology, and is very hard test for. In my last posts I recognized this as the issue, but was unable to explain how the bacteria leaked through the blood-prostate barrier, and why POIS symptoms are not usually associated with chronic bacterial prostatitis. Now I have come up with a reasonable theory to address this problem.
I believe that neurogenic bladder is the added link that transforms chronic bacterial prostatitis into POIS. This is nerve weakness that affects the urinary tract, a result of damage due to viruses, alcoholism, diabetes, vitamin B12 deficiency (full list:
https://www.ninds.nih.gov/Disorders/Patient-Caregiver-Education/Fact-Sheets/Peripheral-Neuropathy-Fact-Sheet). Neurogenic bladder can cause a condition known as retrograde ejaculation. During orgasm, muscles at the end of the bladder neck tighten to prevent retrograde flow of semen. When the nerves that control this contraction are weak, some semen (mixed with infected prostatic fluid) flows into the bladder. This causes urine after orgasm to appear cloudy, while normally it should be clear. The primary receptor that controls the contraction of the bladder neck is the alpha 1 adrenergic receptor, therefore drugs that are agonists of this receptor like pheneylephrine should reduce the degree of retrograde ejaculation and POIS symptoms. I've had great success with this widely available drug lately, and it only takes 30-40 mins to reach peak concentration.
Neurogenic bladder can also cause another condition known as vesicoureteral reflux, or the backward flow of urine from the bladder to the kidneys. This happens because of increased pressure in the bladder, which can be reduced with muscaranic antagonists (such as Benedryl). The bacteria then colonizes up the ureter into the kidneys, known as an ascending infection, impairing renal function. Keep in mind the kidney's are responsible for filtering toxins out of the blood, so this causes you to feel like you're dying, and gives the bacteria the perfect entry system to the bloodstream. The only way to help this is to drink water, which can be unplesant as bacteria in the kidney and bladder both cause frequent urination.
Once the bacteria hit the bloodstream a systemic inflammatory response occurs, causing mast cell activation, a cytokine storm, and lymphocyte activation. The best way to prevent this is with mast cell stabilizers and anti-inflammatories. If the bacteria is extracellular (does not have the capacity to survive the intracellular environment, as I think most bacteria involved in POIS are) then it will induce a Th17 immune response. Th17 cells are incredibly important as they are strongly pro-inflammatory, and have been implicated in the pathogenesis of many inflammatory and autoimmune conditions. Th17 cells also directly correlate with glutamate levels (possible effector mechanism), which can cause excessive activation of NMDA receptors, an important process known as NMDA excitotoxicity. This process can kill neurons and is implicated in many neurodegenerative disorders, and likely most of the neurlogical symptoms of POIS. Best way to prevent this is to first take supplements that reduce Th17 cells (
https://www.selfhacked.com/blog/th17/#Supplements_to_Inhibit_Th17IL-17), second block NMDA receptors with supplements such as zinc and magnesium, or third increase Regulatory T cells (
https://www.selfhacked.com/blog/treg/#Top_8_Picks_to_Increase_Tregs).