The Difference Between Having a Fungal Infection, Having Mold Illness, or Possibly Dealing With Both

by Dr. Susan Tanner, MD

We are frequently asked the question when it comes to mold illness whether it is an actual infection of the body or an illness caused by the mold itself.  The simple answer is that mold illness can involve both but explaining what some of the tests mean may help allay some fears as well as support some of the subsequent treatment recommendations.

Right off the bat, when I think of this topic, I recall a specific example of the confusion the concept of mold illness can cause a patient. This example involves a patient I treated some years ago who presented with severe thyroid dysfunction.  Her history of having lived in a house with multiple episodes of water intrusion supported my doing a blood test referred to as the IgG mold test.  IgG mold test results can reveal immune system reactivity in the body to mold from exposure, past or present.  Unfortunately, her positive lab results registered in her brain as having “mold in her blood”. Alarmed, she took her labs to an infectious disease doctor who told her there was no such thing as mold illness and only the sickest of patients ever got mold in their blood.  After being dismissed by an infectious disease doctor, when this patient returned to my office, it took a tremendous amount of time for me to help her fully understand what her IgG test result really intended to show and why knowing that information could help us address her symptoms.  And, while I THOUGHT I had explained things well from the outset, apparently the information was not sufficient as to not cause her undue anxiety. In order to prevent this scenario from happening again, I was prompted to create handouts that I now supply to patients about the meaning of the labs that I often order.

Testing for Mold in the Body

First, and this concept is important to point out, when we suspect that a patient has mold-triggered illness, the tests that are done are not about the presence of the mold itself in the body, the exception being the presence of spores ( found on culture)  in the sinuses from inhaling contaminated air.   Most of the tests we are looking at have to do with either exposure documentation by identifying patterns of reactivity of the body’s immune system, or markers of inflammation which are similarly set off by the ongoing exposure to mycotoxins.   When we conduct a mycotoxin urine test, again, we are not looking for the presence of mold in the body, but the toxins that the molds produce in their own metabolism. Some of the tests that may be helpful for these goals include the TGFbeta1, VEG-F, and less commonly performed, C3a and C4a. Other times, the suspicion of mold/mycotoxin illness is supported by the imbalance of many hormonal systems as indicated in testing that looks at levels of growth hormone, thyroid, and adrenal function.

Additionally, a urine organic acids test may reveal significant oxidative stress in the cell energy pathways. When this shows up, really digging into the patient’s history for what may be inciting these deficiencies is necessary.  In my clinical experience, I have found that mold and mycotoxins are often a significant part of the problem.

Symptoms Can Indicate the Cause

The presenting symptoms of a patient suffering from mold and mycotoxin illness are what lead us to conduct any of these tests; they can be variable in both presentation and severity.   Fatigue and brain fog are some of the most common complaints, but obviously, these are both non-specific and non-descriptive and require a lot more investigation and attention. A temporal history that is detailed and thorough is necessary for every patient, which includes information about their living and working environments, previous illnesses, chemical exposures, etc.  If a patient has an environmental history of living in a water-damaged home, this immediately brings to mind the necessity of testing for the impact of mycotoxins on the biochemistry of the body.

Where Fungal Infection Fits

The digestive tract is a system that can be impacted by both mold and mycotoxin exposure and fungal infection, such as the overgrowth of candida.  In these cases when a patient has fungal overgrowth, it is necessary to both treat the candida as an infection as well as mitigate the impact of the mycotoxins that candida can produce inside the body.  Where this can get more complicated is in patients who have had mold exposure, thus reducing the immune protectivity of the gut lining, leading to bacterial and yeast overgrowth–so they have both the infection and the mold exposure.  In these cases the source of the mycotoxins must be addressed, the gut immunity has to be strengthened, and the candida overgrowth has to be decreased with antifungal medications.

Patients who have active mold spores growing in their sinuses or bronchi also require a multi-pronged approach.  We now know this can happen from the paper published by Dr. Dennis and colleagues showing the extracted fungal polyps in the sinuses producing a halo of mycotoxins in culture. Obviously, in these cases, the air containing the mold and mycotoxins must be addressed for the patient to get better.  Simultaneously, ridding the respiratory tract of any adherent mold spores must also be done.  Sometimes these are so embedded to have caused fungal balls or polyps in the sinuses, and surgical intervention may be needed to remove these.  Other times the fungal overgrowth is more superficial and responds well to antifungal spray or nebulization.   The time that the mold spends in the respiratory tract relates greatly to the level of mycotoxins that the body has to deal with. Shorter exposures do not usually cause colonization, but being exposed to mold spores often and over time can. The use of liver support items, such as glutathione, resveratrol, and supporting methylation pathways in some patients with vitamins B12 and B6 among many others are useful and necessary steps.  Binding the release of mycotoxin byproducts from the liver with chitosan, charcoal, clay, or zeolite are other steps necessary to keep them from recirculating in the body.

Other Fungal Infections

Other fungal infections, such as athlete’s foot, vaginal candidiasis, jock itch, and tinea versicolor are all manifestations of fungal infection.  In certain tropical countries, there are molds that actually do invade the skin and tissues as well.  These are true infections and are not necessarily from a mycotoxin-laden environment–although, if you are plagued with frequent fungal infections of any type, you should test your environment for mold exposure, in my opinion.  It might be argued that the skin or organs are more prone to succumb to these infections if the overall immunity is suppressed by mold/mycotoxins, but that is not always the case.  Diet, hygiene, and usage of various topical products may reduce skin barrier function and immunity leaving one more prone to these infections, as can the use of strong antibiotics.

In conclusion, I hope my explanation clears up any confusion about the fungal infections vs. mold/mycotoxin illness and where and why these may present themselves and possibly overlap.  It is definitely possible to have both, but in our world of environmental medicine, our focus is more commonly on the mold/mycotoxin impact and how it is affecting the body and overall health.

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