Mycotoxin quantification in fungal/mold allergy
Question:
1/25/2022
In the past couple of years, I have had several patients inquire about testing urine or blood for mycotoxins. My understanding is that this testing is not helpful under any circumstance but some of the primary care practitioners in our area are now offering this test to patients for an out-of-pocket fee. Patients with mold allergy have been particularly interested in this and there are numerous online resources expounding the benefits of such testing. Could you please comment on whether or not there is any indication for testing of urine or blood for mycotoxins and perhaps provide a few reputable references?
Answer:
Mycotoxins are a complicated mixture of substances produced by a variety of fungi, likely to provide a competitive advantage for nutrients. Beta lactam antibiotics, a mycotoxin, were first noted to have negative effects on growth of bacteria in a fungal culture. The role for mycotoxins in causing human disease is less clear (1,2). Mycotoxins can be detected in body tissues as well as urine, and advocates of mycotoxins role in human disease use this evidence to support potential pathogenic effects (3). Most of the evidence showing a negative effect of mycotoxin on mammalian physiology is related to ingestion of food stuffs contaminated with fungi (3,4). Human urinary mycotoxin levels are associated with fungal exposure, but this does not confirm importance in human disease (5,6).
Fungi are ubiquitous in our environment and, in general, exposure to fungal spores or airborne fungal material does not result in disease. Environments associated with fungi, particularly high humidity indoor environments, are associated with symptoms (7,8). Fungal evaluations after hurricanes Katrina and Rita documented high level human fungal exposure but could not correlate health outcomes with degree of fungal exposure (9). Symptoms associated with fungi, but not necessarily caused by fungi, coupled with the term ‘toxin’ in mycotoxin has resulted in the conclusion that mycotoxin presence is diagnostic or causal of disease. In my opinion, there is no evidence that the presence of specific mycotoxin in urine or other body tissue identifies disease but may identify fungal exposure. Allergy to fungal spores is not related to mycotoxin.
In summary, I do not feel that measurement of urinary mycotoxins should be used in assessing disease or symptoms or fungal allergy. There may be value of such testing in epidemiologic studies of fungal exposure, but there are no data to show a relationship with human disease or allergy.
1. Jarvis, BB; Miller, JD. Mycotoxins as harmful indoor air contaminants. Appl. Microbiol Biotechnol 2005, 66, 367–372.
2. Mazur, LJ; Kim, J. Spectrum of noninfectous health effects from molds. Pediatrics 2006, 18, 1909–1926
3. Anfossi, Laura, Cristina Giovannoli, and Claudio Baggiani. "Mycotoxin detection." Current opinion in biotechnology 37 (2016): 120-126.
4. Huwig, Alexander, et al. "Mycotoxin detoxication of animal feed by different adsorbents." Toxicology letters 122.2 (2001): 179-188.
5. Huybrechts, B., et al. "Fast and sensitive LC–MS/MS method measuring human mycotoxin exposure using biomarkers in urine." Archives of toxicology 89.11 (2015): 1993-2005.
6. Rodríguez-Carrasco, Yelko, et al. "Exposure assessment approach through mycotoxin/creatinine ratio evaluation in urine by GC–MS/MS." Food and chemical toxicology 72 (2014): 69-75.
7. Zuo, Chunying, Lin Luo, and Weiwei Liu. "Effects of increased humidity on physiological responses, thermal comfort, perceived air quality, and Sick Building Syndrome symptoms at elevated indoor temperatures for subjects in a hot‐humid climate." Indoor air 31.2 (2021): 524-540.
8. Health concerns associated with mold in water-damaged homes after hurricanes Katrina and Rita – New Orleans area, Louisiana October 2005. Morb Mortal Weekly Rep 2006, 55, 41–44.
9. Barbeau DN, Grimsley LF, White LE et al. Mold exposure and health effects following hurricanes Katrina and Rita. Annual Rev Public Health 2020;31:165-72 https://doi.org/10.1146/annurev.publhealth.012809.103643
All my best.
Dennis K. Ledford, MD, FAAAAI