11/1909. A unique case of vibroacoustic disease: a tribute to an extraordinary patient. This paper describes the case of a patient, Mr. A, who died in 1987. The information provided by Mr. A in life, and his insistence on making a will demanding an autopsy on his death, has given us invaluable data on Vibroacoustic disease (VAD). Mr. A was an intellectually curious man who researched the medical literature related to his condition, and compared it to his own experience. He would describe all his sensations during his many epileptic seizures. Solely because of the results of Mr. A's autopsy, new avenues of research were initiated. These have led to new concepts and exciting new perspectives on noise-induced extraaural pathology. VAD is today a well-established and easily diagnosed entity. This paper is a tribute to Mr. A, in whose honor we have an on-going commitment to establish VAD as an occupational disease, reimbursable by Worker's Compensation. ( info) |
12/1909. Facial dyskinesia induced by auditory stimulation: a report of four cases. INTRODUCTION: The Vibroacoustic disease (VAD) is an occupational pathology induced by long-term (>10 yr) exposure to large pressure amplitude (> or = 90 dB SPL) and low frequency (< or = 500 Hz) noise. During studies contributing to the characterization of VAD, abnormal facial movements induced by repetitive auditory stimuli were observed in one individual employed as an aeronautical mechanic. The goal of this study was to investigate the existence of movement disorders triggered by auditory stimuli in a group of VAD-diagnosed patients. methods: Sixty VAD patients received auditory and median nerve stimulation. Simultaneously, EEG monitoring was performed. RESULTS: Abnormal myoclonus movements were triggered by auditory stimuli in four patients. EEG recordings were normal in all 60 patients. Stimulation of the median nerves did not trigger any abnormal movements. CONCLUSION: These data suggest that this facial dyskinesia has a subcortical origin. ( info) |
13/1909. epilepsy in the vibroacoustic disease: a case report. INTRODUCTION: Late-onset epilepsy was one of the first neurological problems identified in patients diagnosed with vibroacoustic disease. Other clinical situations, such as automatisms and rage-like reaction crises were also observed. Some cases of epileptic seizures were triggered by different types of stimuli. CASE REPORT: This study describes the clinical case of a 30-yr-old male metal-worker who had epileptic seizures when he used vibratory tools common to his profession, such as drills and sanders. We performed a 21-channel EEG during a seizure induced in the laboratory by direct contact of a vibratory tool with his right hand. This allowed us to view the electrical discharge of his left hemisphere. The entire procedure was simultaneously videotaped while a partial motor crisis was observed. brain MRI of this subject revealed multiple hyperintense focal lesions in the sub-cortical white matter. echocardiography revealed thickening of the pericardium and valve structures. COMMENTARY: To the authors' knowledge, this is the first documented case of reflex epilepsy due to vibratory stimuli. We briefly discuss the possible pathophysiological mechanisms of this clinical event. ( info) |
14/1909. Chronic toxic encephalopathy in a painter exposed to mixed solvents. This paper describes symptoms and findings in a 57-year-old painter who had been exposed to various organic solvents for over 30 years. He began to work as a painter at 16 years of age, frequently working in poorly ventilated areas; he used solvents to remove paint from the skin of his arms and hands at the end of each work shift. The patient and his family noticed impaired short-term memory function and changes in affect in his early forties, which progressed until after he stopped working and was thus no longer exposed to paints and solvents. After the patient's exposures had ended, serial neuropsychological testing revealed persistent cognitive deficits without evidence of further progression, and improvement in some domains. magnetic resonance imaging revealed global and symmetrical volume loss, involving more white than gray matter. The findings in this patient are consistent with chronic toxic encephalopathy and are differentiated from other dementing processes such as Alzheimer's disease, multi-infarct (vascular) dementia, and alcoholic dementia. Previous descriptions in the literature of persistent neurobehavioral effects associated with chronic exposure to organic solvents corroborate the findings in this case. ( info) |
15/1909. asbestos-related pleural disease in Western Australian gold-miners. Three retired gold-mine workers from western australia (WA) were diagnose with asbestos-related pleural disease (two with pleural plaques and one with mesothelioma). asbestos fibres have been found in air samples from WA gold-mines, and all three patients had worked in these mines (for five to 17 years) and had no other significant known asbestos exposure. To our knowledge, this is the first report of asbestos-related disease in gold-mine workers. ( info) |
16/1909. mycobacterium sp. as a possible cause of hypersensitivity pneumonitis in machine workers. hypersensitivity pneumonitis (HP) in workers exposed to metal removal fluids (MRFs) is increasing. This study supports the hypothesis that aerosolized mycobacteria colonizing the MRFs likely cause the disease. Three case studies of HP outbreaks among metal workers showed potentially high exposures to a rare and newly proposed mycobacterium species. Retrospective review of samples submitted to our laboratory showed an association between presence of mycobacteria and HP. ( info) |
17/1909. Gz associated stenosis of the cervical spinal canal in fighter pilots. Previous magnetic resonance imaging (MRI) studies have shown that repeated exposure to Gz forces can cause premature degenerative changes of the cervical spine (i.e. a work-related disease). This paper reports on two clinical cases of Gz-associated degenerative cervical spinal stenosis caused by dorsal osteophytes in fighter pilots. Conventional x-rays and MRI were used to demonstrate narrowing of the cervical spinal canal. The first case was complicated by a C6-7 intervertebral disk prolapse and a congenitally narrow spinal canal. The second case involved progressive degenerative spinal stenosis in the C5-6 disk space which required surgery. The findings in this case were confirmed by surgery which showed posterior osteophytes and thickened ligaments compressing the cervical medulla. These two cases suggest that Gz forces can cause degenerative spinal stenosis of the cervical spine. Flight safety may be jeopardized if symptoms and signs of medullar compression occur during high Gz stress. It is recommended that student fighter pilots undergo conventional x-rays and MRI studies in order to screen out and reject candidates with a congenitally narrow spinal canal. These examination methods might be useful in fighter pilots' periodic medical check-ups in order to reveal acquired degenerative spinal stenosis. ( info) |
18/1909. Outbreak of Hendra-like virus--malaysia and singapore, 1998-1999. During September 29, 1998-April 4, 1999, 229 cases of febrile encephalitis (111 [48%] fatal) were reported to the Malaysian Ministry of health (MOH). During March 13-19, 1999, nine cases of similar encephalitic illnesses (one fatal) and two cases of respiratory illness occurred among abattoir workers in singapore. Tissue culture isolation identified a previously unknown infectious agent from ill patients. This report summarizes the preliminary epidemiologic and laboratory investigations of these cases, which indicate that a previously unrecognized paramyxovirus related to, but distinct from, the Australian hendra virus is associated with this outbreak. ( info) |
19/1909. Occupational IgE-mediated asthma, rhinoconjunctivitis, and contact urticaria caused by Easter lily (lilium longiflorum) and tulip. BACKGROUND: We report on IgE-mediated asthma, rhinoconjunctivitis, and contact urticaria to two liliaceae plants, tulip and Easter lily (lilium longiflorum), diagnosed in a floral shop worker. methods: Occupational asthma was diagnosed according to patient history, PEF monitoring, and a work-simulating provocation test. Flower-specific IgE was studied, and RAST inhibition tests were performed. RESULTS: skin prick testing showed positive reactions to tulip, Easter lily, and chrysanthemum. Total IgE was 180 kU/I, and specific IgE to tulip was 2.6 and to Easter lily 6.5 kU/I. In the RAST-inhibition test, no cross-reactivity was found. Occupational asthma was diagnosed by peak flow monitoring at work and at home, as well as specific inhalation challenge with Easter lily, with an immediate 18% reduction in PEF. In addition, contact urticaria and conjunctivitis were diagnosed. After a 9-year follow-up without exposure to lilies, the skin prick tests to L. longiflorum and tulip were still positive, but the specific IgE had disappeared. CONCLUSIONS: A case of IgE-mediated occupational asthma, rhinoconjunctivitis, and contact urticaria caused by L. longiflorum and tulip is presented. RAST inhibition tests indicated concomitant sensitization to the two liliaceae plants. ( info) |
20/1909. Occupational neutrophilic asthma. Occupational asthma is typically associated with an eosinophilic bronchitis. The case of a 41-year-old woman who developed symptoms of asthma after occupational exposure to metal working fluids is reported. The diagnosis of asthma was confirmed by an forced expiratory volume in 1 s (FEV1) of 1.7 (59% predicted), with 11% reversibility after inhaled bronchodilator and a provocation concentration of methacholine to cause a fall in FEV1 of 20% (PC20) of 0.4 mg/mL. Induced sputum examination showed a marked neutrophilia. Over the next six months, serial sputum analyses confirmed the presence of a marked sterile neutrophilic bronchitis during periods of occupational exposure to metal working fluids, which resolved when the patient was away from work and recurred when she returned to work. The sputum findings were mirrored by corresponding changes in spirometry and PC20 methacholine. The findings indicate the occurrence of occupational asthma associated with an intense, sterile neutrophilic bronchitis after exposure to metal working fluids. ( info) |