You’ve experienced it before: It’s that blah feeling you have the days following that nasty cold or GI bug. You haven’t regained all your energy and you’re a bit more irritable. Staying in bed and sleeping seems like the perfect Saturday night. You feel like you are on this hamster wheel—never feeling as bad as when you were sick but also never feeling like yourself again. This is known as post infection syndrome.

Post infection syndrome has been recognized for decades. However, it is rarely discussed unless there are overt symptoms that have a medical history and have been previously described and named. Some post infection syndromes carry their own unique diagnostic names and criteria. Guillain Barre Syndrome may occur after a herpes infection (Epstein-Barr virus) and rheumatic fever may follow an infection with Streptococcus pyogenes.

Top 3 symptoms of post infection syndrome:

  • Fatigue (includes mental fatigue)
  • Depression
  • Weakness/Achiness

Hands down, the number one complaint, post infection, is fatigue. It is normally generalized fatigue but may also present just as “brain fog.” Other related, but likely secondary symptoms are:

  • Skin rashes
  • Pain

Many of these symptoms do have a clear laboratory track record and can be detected by your doctor, both thorough questioning and lab diagnostics. Fever is not usually found once the acute infection has passed. In fact, we will commonly find slightly lower than the patient’s normal temperature in the post infectious phase.

There is a lot of detail regarding this topic, so we will be breaking this into a multi-part series. For now, we will review the basics.

The Initial Workup

The first thing to rule out may seem rather obvious but I can tell you that it is largely overlooked: you must first find out whether or not the infection has cleared. Most infections will last a couple of days to a few weeks. However, there are certain pathogens that we classify as persistent. Persistent infections will commonly last months, if not years. Although all classifications of infections (bacteria, fungus, virus, parasitic) have the ability to maintain this schedule, viral and fungal pathogens are most notorious. So, before we can discuss post infectious syndrome, we must first rule out an active infection.

Now That We Have Ruled Out an Active Infection…

Secondly, we need to develop a timeline. Did your current symptoms, in fact, coincide with the onset of the original infection? If yes, then we must look into the infection-immune interaction and more importantly the downregulation of this interaction.

Cortisol is an important part of the story when we discuss post infection syndrome. Cortisol plays an immunomodulatory role; in essence, it helps to regulate the immune response. Without it, our immune system would run wild, chewing up gobs of energy and leaving inflammation and destruction in its wake. Yes, the immune system is good, but it can create a lot of waste. Cortisol helps to keep this process from going on too long and getting out of hand.

Let’s Chat More About Cortisol

Cortisol, like many hormones, is regulated via a negative feedback mechanism. For a bit more information on how this works, check out our “Adrenal Fatigue Isn’t Real” article (https://gatewaynaturalmedicine.com/adrenal-fatigue-not-real/). Under normal circumstances, cortisol will be released to ‘calm down’ the immune response and return it to its resting state. The body then repairs and regains what was lost and is ready to fight another pathogen.

Sometimes cortisol is released in such high amounts or for such prolonged periods of time that this exposure causes the body to react abruptly to shut down cortisol production. In either case, cortisol for too long or too much cortisol will be presented to the brain.  The brain will register this as inappropriate and attempt to compensate by shutting down cortisol signaling, thus reduce cortisol levels.  On top of that, some infections even have the ability to stimulate cortisol on their own, further elevating cortisol levels. This happens via a proinflammatory protein TNFα, IL-1, or IL-6. In turn, the signal shuts down to release more cortisol in an attempt to calm things down. This feedback mechanism may continue on and cause cortisol to fall low.

Low cortisol can lead to sugar imbalance, fatigue, and blood pressure dysregulation. This is a protective mechanism to attempt to preserve the HPA axis function and to avoid cellular down regulation of cortisol receptors. This may also cause your cortisol to drop.Cortisol depletion is a very common finding in patients with post infectious syndrome. These low cortisol levels are the foundation of this pathology.

In post infection syndrome, the normal mechanisms are not restored, and the body learns new patterns that leave the patient feeling depleted.

Nutrient, Antioxidant and Mineral Depletion

Infections induce a high amount of oxidative stress, thus requiring an equal, yet opposite, remedy. These are known as antioxidants. Antioxidants are normally consumed at a relative constant rate in the diet and are recycled when other vitamins and minerals are balanced. This is a game of give and take. There has to be enough nutrients on-tap to handle the higher load of oxidation post infection. Again, we are dealing with a lot of inflammation and a load of cellular damage that must be quelled.

Anorexia (loss of appetite) is commonly found during an acute infection. For a short period of time, this may be an advantage. Fasting can improve short-burst immunity and promote cellular turn-over. Not to mention, the lack of food consumption guarantees the patient is not consuming anything that could halt the immune system, such as sugar, or put more stress on it, such as the case with food sensitivities.

If the decreased appetite lingers for too long, however, it will leave the patient nutrient and calorically depleted. This is normally a non-issue if the infection was to last only a couple of days. Your body can store up, much like a bank account. But, just like money, if it is not replaced, it will run dry and you will be in debt. This “antioxidant debt” will expose you to increased damage because your body, even under normal conditions, produces oxidative damage and needs these resources to repair. The same is the case for different minerals – leaving the patient in a constant state of playing catch up.

Common antioxidants: Selenium, Vitamin C, Vitamin E and CoQ10

Other antioxidant options: Green and red drinks (from fruits and veggies) are also popular as they can be easily consumed or hidden in other things to help children consume them.

Reduction of Stress Hormone

Stress is not purely a symptom of emotions. Infections are a large stimulus of stress on the body.

Equally as confusing, stress hormones are not only released when you’re late for work or lose your keys. They are also released when you change body positions, the weather pattern shifts (barometric pressures), and during exercise. Much like our discussion on antioxidants, hormones can be depleted as well, but not in the same fashion. Antioxidant depletion is your body overspending resources, whereas a depletion in stress hormones is your body learning to sustain this new high stress level. The exact mechanisms are beyond this article; in short, there is a negative feedback loop taking place. As stress hormones remain high, the brain will eventually stop asking for them to be released. Sometimes, once the stress stimulus has subsided the system does not reset itself and this pattern continues.

Vitamin E

Yes, we had to give Vitamin E its own category because it is that important when evaluating these patients. The immune system and the inflammatory process is an orchestrated process that involves many cells and even more communicating compounds. Fatty compounds, like Eicosanoids, have hormone-like affects and can control different immune cells. In prolonged inflammation, the free fatty substances no longer support the level of the compounds that are needed, so the body must find another reservoir to pluck them from. Low and behold we have a massive store of these fatty substances in our cellular membranes. So, our body will cannibalize the integrity of our cells to continue the immune/inflammatory process. This leaves the cells weak and unable to freely pass products in and out, which eventually leads to a poor functioning cell and thus the cell dies. This will further contribute to the mess the body will need to clean up. Vitamin E not only will help in the antioxidant category, it can also aid in the restoration of cell membrane fluidity. We prefer formulas that are high in tocotrienols, as they seem to have superior availability and action.

Wrapping it all up

There are many avenues to investigate when treating a patient for post infection syndrome. A variety of other diagnoses must be ruled out before coming to a clinical conclusion of post infection syndrome. The best place to start for patient or clinician will be to record a timeline of when symptoms occurred. From there, a series of tests can be performed to guide the decision-making and treatment recommendations. There are many other angles to look at and options for therapy. We will review these later in this series.