Sick Building Syndrome: is mould the cause?

Moulds are responsible for diseases in humans through the three pathogenetic mechanisms of infection, allergy, and toxicity. Fungal infection is especially a risk factor for immunodeficient patients, but it occurs in immunocompetent patients as well. Fungal allergy is manifested as bronchial asthma, hypersensitivity pneumonitis, allergic bronchopulmonary aspergillosis, or allergic fungal sinusitis. Mycotoxicosis is almost exclusively the result of ingestion of mould-contaminated foodstuffs. In each case there is specificity for the etiologic mould. There is controversy regarding the ability of indoor airborne mould spores to cause human disease through non-specific toxicity via the inhalation route. Pulmonary mycotoxicosis is an established, although rare, occupational disease of farmers who inhale enormous quantities of mycotoxins, endotoxins, and other toxic chemicals from contaminated silage. Other conditions attributed to indoor airborne mycotoxin are unproven. These include infantile pulmonary hemosiderosis, epistaxis, 'toxic encephalopathy', immune dysregulation and a variety of subjective complaints without objective signs of pathology such as fatigue, headache, dyspnea, gastrointestinal distress, neuromuscular and skeletal complaints, etc. Non-specific irritation from moulds via the inhalation route is also a controversial subject that remains unproven. Published studies alleging an epidemiologic causal relationship are unconvincing.

The medical effects of mold exposure.

Exposure to molds can cause human disease through several well-defined mechanisms. In addition, many new mold-related illnesses have been hypothesized in recent years that remain largely or completely unproved. Concerns about mold exposure and its effects are so common that all health care providers, particularly allergists and immunologists, are frequently faced with issues regarding these real and asserted mold-related illnesses. The purpose of this position paper is to provide a state-of-the-art review of the role that molds are known to play in human disease, including asthma, allergic rhinitis, allergic bronchopulmonary aspergillosis, sinusitis, and hypersensitivity pneumonitis. In addition, other purported mold-related illnesses and the data that currently exist to support them are carefully reviewed, as are the currently available approaches for the evaluation of both patients and the environment.

The interaction of social network size and stressful life events predict delayed-type hypersensitivity among women with metastatic breast cancer.

This study examined relationships between social support, stressful life events and antigen-specific cell-mediated immunity. Participants were 72 women with documented metastatic breast carcinoma, who completed self-report measures of social support and life stress. Immune response was assessed using the delayed type hypersensitivity (DTH) skin test. Number of positive antigens was significantly related to the interaction of social network size and stressful life events (p<0.05). Number of positive antigens was greater for women who had experienced a high frequency of stressful life events but who reported a larger network of support. However, social network size was inversely related to DTH response among women who had experienced fewer stressful life events. Average induration size was not significantly related to the quality of social support, life stress per se, or their interactions. The relationship between social network size and immune response in women with metastatic breast cancer depends on prior stressful life experience.

Are indoor molds causing a new disease?

Three mechanisms for disease caused by mold-infection, allergy, and toxicity-are established and well recognized by clinicians. In each case the corresponding diseases are specific to a particular fungus. The mechanisms involved include a recognized inflammatory pathology that leads to objective clinical evidence of disease. Recent widespread litigation has arisen out of an unproved assertion that exposure to indoor molds causes an ill-defined illness. This illness is characterized by the absence of objective evidence of disease and by the lack of a defined pathology. There is usually no specificity for the involved fungus purported to cause the illness. Those publications that claim such an illness are reviewed. They are found to lack scientific validity, often on the basis of faulty methodology and insufficient information. There is no coherent clinical description for the presumed illness. Recommendations are offered for published reports and studies to address this problem.

Toxic mold: phantom risk vs science.

OBJECTIVE: To review the available literature on the subject of fungi (molds) and their potential impact on health and to segregate information that has scientific validity from information that is yet unproved and controversial. DATA SOURCES: This review represents a synthesis of the available literature in this area with the authors' collective experience with many patients presenting with complaints of mold-related illness. STUDY SELECTION: Pertinent scientific investigation on toxic mold issues and previously published reviews on this and related subjects that met the educational objectives were critically reviewed. RESULTS: Indoor mold growth is variable, and its discovery in a building does not necessarily mean occupants have been exposed. Human response to fungal antigens may induce IgE or IgG antibodies that connote prior exposure but not necessarily a symptomatic state. Mold-related disease has been discussed in the framework of noncontroversial and controversial disorders. CONCLUSIONS: When mold-related symptoms occur, they are likely the result of transient irritation, allergy, or infection. Building-related illness due to mycotoxicosis has never been proved in the medical literature. Prompt remediation of water-damaged material and infrastructure repair should be the primary response to fungal contamination in buildings.

Environmental sensitivity.

The concept of environmental sensitivity is popular among a small group of physicians who believe that exposure to low levels of numerous environmental chemicals can cause a disease with numerous symptoms but no objective physical or laboratory abnormalities. The condition lacks a clear definition. Numerous theories that have been offered to explain the condition encompass immunotoxic, allergic, autoimmune, neurotoxic, cytotoxic, metabolic, behavioral, psychiatric, iatrogenic, and sociologic mechanisms. Environmental sensitivity has many features in common with other controversial syndromes, such as the chronic fatigue syndrome. Patients with environmental sensitivity frequently are subjected to unproven and unnecessary diagnostic tests and therapeutic modalities. In spite of the lack of physical illness and absence of pathology, patients often experience extreme disability, because their symptoms are triggered by common environmental exposures. The phenomenon of environmental sensitivity needs to be evaluated critically using scientifically sound methods. The practice of clinical ecology encompasses the practices of environmental sensitivity and its theories. Most methods of diagnosis and treatment have been disproved, and the concepts underlying these theories are not scientific. Alternative means of diagnosis and management are presented.