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Black mold exposure, increased C4a and neurologic symptoms


A young patient is seen in our office for controlled asthma and allergic rhinitis, and her mother is concerned that her child's school performance diminished in relationship to a recent discovery of "black toxic mold" in the school, which may have caused "fogginess" with decreased academic focus. The child was taken to an alternative physician who reportedly specializes in Lyme disease and mold toxicity. Blood testing showed an elevated C4a level, which the doctor said was a sign of mold toxicity. The child did not show mold sensitization on skin testing in our office years ago. My questions: 1) can I tell the mother that an elevated C4a level has clinical relevance outside of Lyme disease or autoimmunity (the pt has no history of either), 2) do we have evidence that indoor mold overgrowth is associated with isolated neurologic symptoms, and 3) is there a role for mold aeroallergen skin testing without dermatologic or respiratory tract symptoms?


Your patient or your patient’s family are describing vague symptoms that are associated with an environmental exposure. These situations are rife with anxiety, innuendo, mass psychogenic illness and false associations (Powell). I do not think there is any association of the “black toxic mold” and the “fogginess” but there are physicians and other practitioners who would make these claims (Bush; Chapman; Lees-Haley; Anyanwu; Armstrong). Multisystem complaints without objective findings or definitive testing has been linked with Lyme disease but this is controversial as well (Lantos; Smith; Steere).

1). The increase in C4a does not define any disease or condition and I would reassure the family that this does not diagnose autoimmunity, infection or mold exposure. You may consider repeat testing and include C4, C3 and CH50 to verify the absence of complement activation and consumption. C4a increase is nonspecific and would not explain the symptoms described by your patient.

2). There is no definitive evidence that “black mold” or other indoor mold exposure results in neurologic symptoms, but there is a cloud of controversy around this subject (Bush; Chapman; Anyanwu; Armstrong) Black mold is sometimes used to describe Stachybotrys (Etzel). There may be volatile hydrocarbons causing irritation from exposure but no evidence, unless the Stachybotrys is eaten, that there is a proven medical disease resulting from exposure (Betancourt; Bush).

3). There is no reason to consider testing this patient for specific-IgE to mold.

1. Lantos, Paul M., Paul G. Auwaerter, and Gary P. Wormser. "A systematic review of Borrelia burgdorferi morphologic variants does not support a role in chronic Lyme disease." Clinical Infectious Diseases (2013): cit810.
2. Lantos, Paul M. "Chronic lyme disease." Infectious Disease Clinics of North America 29.2 (2015): 325-340.
3. Steere, Allen C., and Sheila L. Arvikar. "Editorial commentary: what constitutes appropriate treatment of post-lyme disease symptoms and other pain and fatigue syndromes?." Clinical Infectious Diseases 60.12 (2015): 1783-1785.
4. Smith, Aaron J., John Oertle, and Dino Prato. "Chronic Lyme Disease: Persistent Clinical Symptoms Related to Immune Evasion, Antibiotic Resistance and Various Defense Mechanisms of Borrelia burgdorferi." Open Journal of Medical Microbiology 4.04 (2014): 252.
5. Bush, Robert K., et al. "The medical effects of mold exposure." Journal of Allergy and Clinical Immunology 117.2 (2006): 326-333.
6. Powell, Scott A., et al. "Mass psychogenic illness presenting as acute stridor in an adolescent female cohort." Annals of Otology, Rhinology & Laryngology 116.7 (2007): 525-531.
7. Chapman, Jean A., et al. "Toxic mold: phantom risk vs science." Annals of Allergy, Asthma & Immunology 91.3 (2003): 222-232.
8. Lees-Haley, Paul R. "Toxic mold and mycotoxins in neurotoxicity cases: Stachybotrys, Fusarium, Trichoderma, Aspergillus, Penicillium, Cladosporium, Alternaria, Trichothecenes." Psychological Reports 93.2 (2003): 561-584.
9. Anyanwu, Ebere C., Andrew W. Campbell, and Aristo Vojdani. "Neurophysiological effects of chronic indoor environmental toxic mold exposure on children." The Scientific World Journal 3 (2003): 281-290.
10. Armstrong, David. "Amid suits over mold, experts wear two hats." Wall Street Journal 9 (2007).
11. Etzel, Ruth A., et al. "Acute pulmonary hemorrhage in infants associated with exposure to Stachybotrys atra and other fungi." Archives of Pediatrics & Adolescent Medicine 152.8 (1998): 757-762.
12. Betancourt, Doris A., et al. "Microbial volatile organic compound emissions from Stachybotrys chartarum growing on gypsum wallboard and ceiling tile." BMC Microbiology 13.1 (2013): 1.

I hope this information is of help to you and your patient.

All my best.
Dennis K. Ledford, MD, FAAAAI