Cold-provocation testing for the vascular component of hand-arm vibration syndrome in health surveillance.

The aim was to investigate whether the use of infra-red thermography (I-R) and measurement of temperature gradients along the finger could improve the diagnostic accuracy of cold-provocation testing (15 degrees C for 5 min) in vascular hand-arm vibration syndrome (HAVS). Twenty-one controls and 33 individuals with stages 2/3V HAVS were studied. The standard measurement of time to rewarm by 4 degrees C (T4 degrees C) and temperature gradients between the finger tip, base and middle (measured using I-R) were calculated. Receiver Operating Characteristics (ROC) analysis to distinguish between the two groups revealed that for T4 degrees C the area under the ROC curve was not statistically significantly different from 0.5 (0.64 95% confidence interval 0.49-0.76). The difference between the tip and middle portion of the finger during the sixth minute of recovery was the most promising gradient with an area of 0.76 (95% confidence interval 0.62-0.87), and sensitivity and specificity of 57.6% and 85.7% respectively. However, this was not significantly different from that for the time to rewarm by 4 degrees C. In conclusion, the cold-provocation test used in this study does not appear to discriminate between individuals with stage 2/3V HAVS and controls and this is not improved by the measurement of temperature gradients along the fingers using I-R.

Modification of the Stockholm Vascular Scale.

BACKGROUND: Staging hand-arm vibration syndrome (HAVS) depends upon accurate reporting of the extent and frequency of blanching attacks. Reporting may not be repeatable and not all individuals classifiable using the Stockholm Workshop Scale (SWS). For Department of Trade and Industry (Dti) coal miners' assessments, the SWS was modified to include a blanching score. Further modifications, which involve splitting Stage 2V into 'early' and 'late' have been proposed but the impact of this on classification has not been investigated. AIM: To investigate the impact of modifications in the SWS on HAVS classification. METHODS: Staging of individuals with HAVS according to the SWS using two modified scales. Two different cut-offs for defining 'frequent' blanching attacks (>or=3 or >or=7 attacks/week, respectively) were used. RESULTS: One hundred and sixty-five individuals were staged. Using the SWS, 58 and 31% of the population were unclassifiable using the two cut-offs, respectively. The modification splitting Stage 2V reduced the proportions that were unclassifiable to 2 and 9%, respectively, and increased those classified as Stage 2V. The cut-off for frequent attacks used (3 or 7) affected the proportion of individuals falling into the subdivisions of Stage 2 with 17 and 42% being classified as 2Vearly and 45 and 20% as 2Vlate, respectively. CONCLUSIONS: Subdividing Stage 2V enables more individuals to be classified, but the proportion falling into each category is susceptible to the cut-off used for defining frequent attacks. Caution may need to be applied if this categorization is used to make decisions regarding fitness to work.

A screening questionnaire for HAVS?

AIM: To define the diagnostic power of simple questions most applicable for a hand-arm vibration syndrome (HAVS) assessment screening questionnaire. METHOD: Using a binary logistic regression we analysed 365 physician led HAVS health surveillance assessments to identify which questions could form the basis of a screening questionnaire. RESULTS: Four sensorineural related questions regarding tingling and numbness in response to the cold and after using vibrating tools, and two vascular-related questions focusing on the patient's fingers going white on exposure to cold and numbness during an attack of whiteness were identified. CONCLUSIONS: Questions of high sensitivity for screening subjects for the vascular and neurosensory components of HAVS were identified, which can be used to identify those requiring further clinical investigation and functional testing.

Specific IgE to colophony?

BACKGROUND: Colophony (rosin) is a natural product obtained from coniferous trees. It is used in a diverse range of products such as adhesives, ink, paints and soldering fluxes. Some workers exposed to colophony during soldering can develop occupational asthma; at present, no specific IgE test is available to assess sensitization to colophony. METHODS: Serum samples were obtained from exposed symptomatic individuals (n = 7), some with a likely diagnosis of occupational asthma, exposed asymptomatic individuals (n = 10) and unexposed individuals (n = 11). Serum was tested for specific IgE antibodies against a protein extract produced following in vitro challenge of mono-mac-6 cells with colophony extract. RESULTS: Serum from exposed symptomatic individuals showed increased binding of specific IgE antibodies to a range of colophony-cell protein conjugates [29% (2/7) of samples tested when cut-off > 0.1 or 86% (6/7) of samples tested when cut-off > 0%] compared with both the exposed asymptomatic [0% when cut-off > 0.1, or 20% when cut-off > 0% (2/10)] and the non-exposed control populations [0% when cut-off > 0.1, or 27% when cut-off > 0% (3/11)]. CONCLUSIONS: This novel approach for the production of conjugates to assess sensitization to colophony was able to detect specific IgE in colophony-exposed workers with a likely diagnosis of occupational asthma.

Respiratory symptoms, immunology and organism identification in contaminated metalworking fluid workers. What you see is not what you get.

BACKGROUND: Metal working fluids (MWF) constitute a significant respiratory hazard, although symptoms experienced by workers are often poorly investigated and attributed. AIMS: A single possible case of extrinsic allergic alveolitis (EAA) led to a formal workplace investigation. It was clear that other exposed workers were affected. The aim of this study was to accurately quantify the clinical, immunological and microbiological findings in MWF workers following presentation of a sentinel case. METHODS: Eleven of 21 individuals participated; eight were assessed by symptom questionnaire, spirometry and serology and three workers provided blood samples only. The microbes cultured from MWF and air samples were used to determine the presence of precipitating antibodies. RESULTS: Work-related respiratory symptoms were reported in six of eight individuals questioned, two of these complaining of 'flu-like' symptoms. Personal breathing zone measures identified 2.1 x 10(3) to 1.1 x 10(5) colony-forming units/m3 air (CFU/m3). Pseudomonas fluorescens was isolated from air samples. Despite visible 'fungal' contamination of MWF, airborne fungi were detectable in only one sample, at 486 CFU/m3 air. MWF cultured Eurotium sp., Fusarium sp. and Pseudomonas sp. Precipitating IgG antibodies to Pseudomonas sp. were identified in 4/11 and to an extract of the MWF in 3/11. IgG to Pseudomonas was elevated in the two individuals who had the strongest precipitating bands to Pseudomonas sp. CONCLUSIONS: Workplaces with possible EAA must be investigated promptly, thus allowing clinical assessment to be contemporary to exposures and accurate microbiological profiling included to identify the likely cause.

The perceptions of occupational health in primary care.

AIM: A random sample of general practitioners (GPs), practice nurses (PNs) and practice managers (PMs) in Sheffield and Manchester was recruited into a study to evaluate the perceptions of occupational health (OH) in primary care. METHODS: Qualitative data were collected using focus groups with three groups of primary care sector professionals. Quantitative data were collected nationally from 295 GPs using a postal questionnaire. RESULTS: GPs and PNs had minimal OH training, and 60% of GPs reported constraints in addressing OH matters with patients. The lack of referral routes (63 and 67%, respectively) was also seen as a barrier. OH was regarded as a speciality, and primary care professionals preferred to refer patients with OH problems to specialist centres because they perceived barriers to their dealing with the issues. A total of 74% of GPs surveyed thought that speedier access to secondary care would help them to address OH problems. CONCLUSIONS: This study has identified some of the problems associated with delivering OH through primary care. It also demonstrated a need for greater emphasis on OH education in medical and nurse training, and a need for better advice for GPs, PNs and PMs regarding support services for OH.

Job categories and their effect on exposure to fungal alpha-amylase and inhalable dust in the U.K. baking industry.

Enzymes in flour improver, in particular fungal alpha-amylase, are known to be a significant cause of respiratory allergy in the baking industry. This study measured total inhalable dust and fungal alpha-amylase exposures in U.K. bakeries, mills, and a flour improver production and packing facility and determined whether assignment of job description could identify individuals with the highest exposures to fungal alpha-amylase and inhalable dust. A total of 117 personal samples were taken for workers in 19 bakeries, 2 mills, and a flour improver production and packing facility and were analyzed using a monoclonal based immunoassay. Occupational hygiene surveys were undertaken for each site to assign job description and identify individuals who worked directly with flour improvers. Analysis of exposure data identified that mixers and weighers from large bakeries had the highest exposures to both inhalable dust and fungal alpha-amylase among the different categories of bakery workers (p<.01). Currently, the maximum exposure limit for flour dust in the United Kingdom is 10 mg/m(3) (8-hour time-weighted average reference period). In this study 25% of the total dust results for bakers exceeded 10 mg/m(3), and interestingly, 63% of the individuals with exposure levels exceeding 10 mg/m(3) were weighers and mixers. Individuals who worked directly with flour improvers were exposed to higher levels of both inhalable dust and fungal alpha-amylase (p<.01) than those who were not directly handling these products. Before sensitive immunoassays were utilized for the detection of specific inhalable allergens, gravimetric analysis was often used as a surrogate. There was a weak relationship between inhalable dust and fungal alpha-amylase exposures; however, inhalable dust levels could not be used to predict amylase exposures, which highlights the importance of measuring both inhalable dust and fungal alpha-amylase exposures.