Tag: multiple chemical sensitivities

Paraoxonase/MCS

Work in multiple laboratories on paraoxonase polymorphism has shown that this mammal enzyme protects against chlorpyrifos and other organophosphates differentially, depending on which inherited forms of the enzyme predominate. This variable ability to process pesticides exists in humans and is trackable ethnically (1), and very recent articles have suggested the polymorphism may be responsible for host susceptibility to Gulf War syndrome (2,3). Because my own interest is in multiple chemical sensitivity (MCS) mechanisms, I immediately searched Medline (National Library of Medicine, Bethesda, MD) for publications that included paraoxonase and MCS, fibromyalgia, or chronic fatigue syndrome (CFS), which have been suggested as being overlapping or identical with each other and with Gulf War syndrome (4,5). I found no other references at all.

You can read the full article here: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1566473/pdf/envhper00513-0015b.pdf

 

Source: Rowat SC. Paraoxonase/MCS. Environ Health Perspect. 1999 Aug;107(8):A395. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1566473/pdf/envhper00513-0015b.pdf

 

Developing case definitions for symptom-based conditions: the problem of specificity

Symptom-based conditions are postulated organic diseases that are characterized primarily by chronic physical (somatic) symptoms (1, 2). Contemporary conditions associated with multisystem complaints are generally referred to as chronic fatigue syndrome, fibromyalgia, multiple chemical sensitivities, silicone associated atypical rheumatic disease, sick building syndrome, and most recently, Gulf War syndrome (table 1). Possibly related disorders that will not be considered in the following analysis include epidemic neuromyasthenia, hyperventilation syndrome, reactive hypoglycemia, post-lyme disease syndrome, and irritable bowel syndrome (3).

Although the need to consistently define symptombased conditions has been repeatedly emphasized, there has been limited progress in establishing widely accepted diagnostic criteria (1,4). Based on reports in English-language publications, symptom-based conditions were analyzed to determine why it has been difficult to develop case definitions of unique diseases.

You can read the rest of this article here: http://epirev.oxfordjournals.org/content/20/2/148.long

 

Source: Hyams KC. Developing case definitions for symptom-based conditions: the problem of specificity. Epidemiol Rev. 1998;20(2):148-56. http://epirev.oxfordjournals.org/content/20/2/148.long (Full article)

The non-specific environmental syndromes MCS (Multiple Chemical Sensitivity), IEI (Idiopathic Environmental Intolerance) and SBS (Sick Building Syndrome)

Abstract:

This review starts with a clinical description of the most common unspecific environmental diseases, such as Multiple Chemical Sensitivities (MCS), Idiopathic Environmental Intolerances (IEI) and Sick Building Syndrome (SBS). These syndromes are very controversial discussed between scientific medicine and “clinical ecology”. In addition, they have fundamental similarities to Chronic Fatigue Syndrome (CFS) and Fibromyalgia. Finally the spectrum of therapeutic approaches is discussed.

 

Source: Csef H. The non-specific environmental syndromes MCS (Multiple Chemical Sensitivity), IEI (Idiopathic Environmental Intolerance) and SBS (Sick Building Syndrome). Fortschr Med. 1998 Nov 30;116(33):18-20, 22, 24. [Article in German] http://www.ncbi.nlm.nih.gov/pubmed/9889460

 

Medical evaluation of Persian Gulf veterans with fatigue and/or chemical sensitivity

Abstract:

The purpose of this study was to determine if Gulf War veterans with complaints of severe fatigue and/or chemical sensitivity (n = 72) fulfill case definitions for chronic fatigue syndrome (CFS) and/or multiple chemical sensitivity (MCS) and to compare the characteristics of those veterans who received a diagnosis of CFS (n = 24) to a group of non-veterans diagnosed with CFS (n = 95).

Thirty-three veterans received a diagnosis of CFS with 14 having MCS concurrently; an additional six had MCS but did not fulfill a case definition for CFS. The group of fatigued veterans receiving a diagnosis of CFS was comprised of significantly fewer women and fewer Caucasians than the civilian group, and significantly fewer veterans reported a sudden onset to their illness.

Veterans with CFS had a milder form of the illness than their civilian counterparts based on medical examiner assessment of the severity of the symptoms, reported days of reduced activity, and ability to work. Since CFS in veterans seems less severe than that seen in civilians, the prognosis for recovery of veterans with this disorder may be better.

 

Source: Pollet C, Natelson BH, Lange G, Tiersky L, DeLuca J, Policastro T, Desai P, Ottenweller JE, Korn L, Fiedler N, Kipen H. Medical evaluation of Persian Gulf veterans with fatigue and/or chemical sensitivity. J Med. 1998;29(3-4):101-13. http://www.ncbi.nlm.nih.gov/pubmed/9865452

 

Profile of patients with chemical injury and sensitivity

Abstract:

Patients reporting sensitivity to multiple chemicals at levels usually tolerated by the healthy population were administered standardized questionnaires to evaluate their symptoms and the exposures that aggravated these symptoms. Many patients were referred for medical tests. It is thought that patients with chemical sensitivity have organ abnormalities involving the liver, nervous system (brain, including limbic, peripheral, autonomic), immune system, and porphyrin metabolism, probably reflecting chemical injury to these systems.

Laboratory results are not consistent with a psychologic origin of chemical sensitivity. Substantial overlap between chemical sensitivity, fibromyalgia, and chronic fatigue syndrome exists: the latter two conditions often involve chemical sensitivity and may even be the same disorder. Other disorders commonly seen in chemical sensitivity patients include headache (often migraine), chronic fatigue, musculoskeletal aching, chronic respiratory inflammation (rhinitis, sinusitis, laryngitis, asthma), attention deficit, and hyperactivity (affected younger children). Less common disorders include tremor, seizures, and mitral valve prolapse.

Patients with these overlapping disorders should be evaluated for chemical sensitivity and excluded from control groups in future research. Agents whose exposures are associated with symptoms and suspected of causing onset of chemical sensitivity with chronic illness include gasoline, kerosene, natural gas, pesticides (especially chlordane and chlorpyrifos), solvents, new carpet and other renovation materials, adhesives/glues, fiberglass, carbonless copy paper, fabric softener, formaldehyde and glutaraldehyde, carpet shampoos (lauryl sulfate) and other cleaning agents, isocyanates, combustion products (poorly vented gas heaters, overheated batteries), and medications (dinitrochlorobenzene for warts, intranasally packed neosynephrine, prolonged antibiotics, and general anesthesia with petrochemicals).

Multiple mechanisms of chemical injury that magnify response to exposures in chemically sensitive patients can include neurogenic inflammation (respiratory, gastrointestinal, genitourinary), kindling and time-dependent sensitization (neurologic), impaired porphyrin metabolism (multiple organs), and immune activation.

 

Source: Ziem G, McTamney J. Profile of patients with chemical injury and sensitivity. Environ Health Perspect. 1997 Mar;105 Suppl 2:417-36. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1469804/  (Full article)

 

Multiple chemical sensitivity disorder in patients with neurotoxic illnesses

Abstract:

The data of 466 subjects suffering from neurologic disorders which are suggested to be caused by neurotoxic agents in their environment retrospectively was evaluated and documented. Among these cases there were 151 subjects with symptoms of Multiple Chemical Sensitivity Disorder (MCSD). The relationship between the neurological health impairments and neurotoxic agents in the environment of these patients was characterised using five different categories (probable = A, possible = B, uncertain = C, unclarified = D, not probable = E). From the 466 patients 320 subjects (69%) could be assigned to the categories A and B, respectively.

Within theses 320 cases with chronic neurotoxic health impairments 136 subjects (79 females and 57 males) showed signs of MCSD. Age and gender of cases as well as duration and character of exposure to neurotoxic substances retrospectively were assessed from the explicit files of the patients, which had been made anonymous for this purpose. Frequency of characteristic symptoms of neurotoxicity were analysed. Results are given for patients with neurotoxic health impairments with MCSD (n = 136) and without MCSD (n = 184).

Neurotoxic substances which were used as indoor wood preservatives (mainly Pentachlorophenol and/or Lindane) were found to be the causative agents in 63% of the cases with neurotoxic health impairments and MCSD. Other important neurotoxic substances to which the patients were mainly exposed were organic solvents (25%), formaldehyde (15%), dental materials (15%), pyrethroides (13%), and other biocides (19%) (multiple exposures were possible). The time of exposure was calculated as being > or = 10 years for 55% of the patients with MCSD and for 50% of the group with neurotoxic health impairments but without MCSD.

Out of the 184 cases with neurotoxic health impairments but without MCSD there were 22%, and out of the 136 cases with MCSD there were 39% who showed all symptoms of chronic fatigue syndrome. 53% of the cases with MCSD had an allergic disposition compared to only 20% of the cases without MCSD.

This work is not a controlled epidemiological study but a retrospective documentation and evaluation of data related to environmental medicine. With the present documentation in this purely descriptive manner the proof of a causal relationship was not possible or intended. But because corresponding epidemiological studies are lacking, this documentation can give important information on characteristic features of Multiple Chemical Sensitivity Disorder and chronic neurotoxic health impairments. Such information is essential for planning and carrying out epidemiological studies urgently needed in this field.

Comment in:

Comment on K. Lohmann, Anke Pröhl, E. Schwarz. Multiple chemical sensitivity in patients with neurotoxic illnesses. Gesundheitswesen. 1997 [Article in German]

 

Source: Lohmann K, Pröhl A, Schwarz E. Multiple chemical sensitivity disorder in patients with neurotoxic illnesses. Gesundheitswesen. 1996 Jun;58(6):322-31. [Article in German] http://www.ncbi.nlm.nih.gov/pubmed/8766847

 

A controlled comparison of multiple chemical sensitivities and chronic fatigue syndrome

Abstract:

The present study had two objectives: 1) to determine the characteristics that differentiated subjects with multiple chemical sensitivities (MCS), chemical sensitivities (CS), and chronic fatigue syndrome (CFS); and 2) to evaluate the psychiatric and neuropsychological complaints of these groups relative to normal controls.

A cross-sectional comparison was made of the following groups matched for age, sex, and education: 1) patients whose sensitivities to multiple low level chemical exposures began with a defined exposure (MCS; N = 23); 2) patients with sensitivities to multiple chemicals without a clear date of onset (CS; N = 13); 3) patients meeting CDC criteria for Chronic Fatigue Syndrome (CFS; N = 18); and 4) normal controls (N = 18).

Subjects with sensitivities to chemicals (MCS and CS) reported significantly more lifestyle changes due to chemical sensitivities and significantly more chemical substances that made them ill compared with chronic fatigue and normal controls. MCS, CS, and CFS patients had significantly higher rates of current psychiatric disorders than normal controls and reported significantly more physical symptoms with no medical explanation.

Seventy-four percent of MCS and 61% of CFS did not qualify for any current Axis I psychiatric diagnosis. Chemically sensitive subjects without a defined date of onset (CS) had the highest rate of Axis I psychiatric disorders (69%). On the MMPI-2, 44% of MCS, 42% of CS, 53% of CFS, and none of the controls achieved clinically significant elevations on scales associated with somatoform disorders.

With the exception of one complex test of visual memory, no significant differences were noted among the groups on tests of neuropsychological function. Standardized measures of psychiatric and neuropsychological function did not differentiate subjects with sensitivities to chemicals from those with chronic fatigue. Subjects with sensitivities to chemicals and no clear date of onset had the highest rate of psychiatric morbidity. Standardized neuropsychological tests did not substantiate the cognitive impairment reported symptomatically. Cognitive deficits may become apparent under controlled exposure conditions.

 

Source: Fiedler N, Kipen HM, DeLuca J, Kelly-McNeil K, Natelson B. A controlled comparison of multiple chemical sensitivities and chronic fatigue syndrome. Psychosom Med. 1996 Jan-Feb;58(1):38-49. http://www.ncbi.nlm.nih.gov/pubmed/8677287

 

Comparison of patients with chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities

Abstract:

BACKGROUND: Chronic fatigue syndrome (CFS), fibromyalgia (FM), and multiple chemical sensitivities (MCS) are conditions associated with fatigue and a variety of other symptoms that appear to share many clinical and demographic features. Our objectives were to describe the similarities and differences among patients with CFS, FM, and MCS. Additional objectives were to determine how frequently patients with MCS and FM met the criteria for CFS and if they differed in their health locus of control.

METHODS: Demographic, clinical, and psychosocial measures were prospectively collected in 90 patients, 30 each with CFS, FM, and MCS. Patients were recruited from a university-based referral clinic devoted to the evaluation and treatment of chronic fatigue and three private practices. Variables included demographic features, symptoms characteristic of each condition, psychological complaints, a measure of health locus of control, and information on health care use.

RESULTS: Overall, the three patient groups were remarkably similar in demographic characteristics and the presence of specific symptoms. Patients with CFS and FM frequently reported symptoms compatible with MCS. Likewise, 70% of patients with FM and 30% of those with MCS met the criteria for CFS. Health care use was substantial among patients with CFS, FM, and MCS, with an average of 22.1, 39.7, and 23.3 visits, respectively, to a medical provider during the prior year. Health locus of control did not differ among the three populations.

CONCLUSIONS: In general, demographic and clinical factors and health locus of control do not clearly distinguish patients with CFS, FM, and MCS. Symptoms typical of each disorder are prevalent in the other two conditions.

Comment in: Chronic fatigue, fibromyalgia, and chemical sensitivity: overlapping disorders. [Arch Intern Med. 1995]

 

Source: Buchwald D, Garrity D. Comparison of patients with chronic fatigue syndrome, fibromyalgia, and multiple chemical sensitivities. Arch Intern Med. 1994 Sep 26;154(18):2049-53. http://www.ncbi.nlm.nih.gov/pubmed/8092909

 

Neuropsychology and psychology of MCS

Abstract:

Neurological symptoms are frequently reported by patients with multiple chemical sensitivities (MCS). Methods to compare the psychiatric, personality, and neuropsychological function of patients with MCS, chronic fatigue syndrome (CFS), and normal controls are described. Increased rates of Axis I psychiatric diagnoses are observed in the literature for MCS and CFS subjects relative to controls.

Findings on the MMPI-2 and the Toronto Alexithymia Scale reveal profiles consistent with the tendency to report somatic rather than emotional symptoms in response to stress. However, many of the reported somatic symptoms also coincide with those found in neurologic disorders. The overall neuropsychological profile for MCS subjects does not reflect cognitive impairment.

Relative to normal controls, the only difference in neuropsychological performance observed is reduced recognition of nontarget designs on a visual memory task. More fruitful areas for future psychological research will include measurement of the interaction between behavioral response styles and attentional processes in cognition, as well as observations under controlled challenge conditions.

 

Source: Fiedler N, Kipen H, Deluca J, Kelly-McNeil K, Natelson B. Neuropsychology and psychology of MCS. Toxicol Ind Health. 1994 Jul-Oct;10(4-5):545-54. http://www.ncbi.nlm.nih.gov/pubmed/7778113