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Background: To evaluate the colonisation rate and type in different groups of patients with chronic lung diseases, bronchial lavage (BL) fluid was investigated for bacteria. Methods: All patients underwent fibre-optic bronchoscopy as part of routine investigation for remote haemoptysis or nodule investigation. The standard procedure included BL and microbiological culture providing the total number of colony forming units (cfu)/mL and the number of potential pathogenic bacteria (ppb)/mL. Three groups of patients were included: 48 persons had a final diagnosis of no pathology, 53 patients with chronic obstructive pulmonary disease in a stable phase and 32 patients with a final diagnosis of bronchiectasis. Results: The median number of cfu cultured from patients with bronchiectasis was 105 cfu/mL compared to 5 103 cfu/mL in patients with COPD and 104 cfu/mL in persons with no pathology. The ppb colonisation rate varied from 10% in persons with no pathology to 43% in patients diagnosed with chronic obstructive pulmonary disease (COPD) and 63% in patients with bronchiectasis. The most frequent bacteria isolated was Haemophilus influenzae. Colonisation rates were associated with frequencies of respiratory infections; patients with bronchiectasis reported a median of three infections per year, patients with COPD reported one infection per year, and persons without pathology reported 0 infections per year ( P < 0.05). Within each group a large patient-to-patient variation was found. Conclusions: Different groups of patients with chronic pulmonary diseases have very different colonisation rates. Patients with bronchiectasis have the highest colonisation rate. This correlates to the reported frequency of lower respiratory tract infections. Please cite this paper as: Weinreich UM and Korsgaard J. Bacterial colonisation of lower airways in health and chronic lung disease. The Clinical Respiratory Journal 2008; 2: 116–122. [ABSTRACT FROM AUTHOR]

Estimated indoor climate conditions in unheated summer cottages offers house-dust mites unfavorable temperature and feeding conditions while giving them optimum humidity conditions. We aimed to estimate the exposure level of house-dust mites in summer cottages. A total of 37 summer cottages were sampled for house dust and storage mites in three locations and the results compared with samples from 33 patients suspected of house-dust mite allergy and living in ordinary houses. The processed dust samples were investigated by microscopy and exposure levels given as number of mites per 0.1 g dust. The summer cottages were without exception all heavily infested with threefold or higher concentrations of both house dust and storage mites in comparison with ordinary houses. In unheated summer cottages were found tropical high concentrations of house dust and storage mites with a median concentration of house-dust mites in mattress dust of 2000 house-dust mites/g of dust which corresponds to an average of 40 μg allergen/g of mattress dust. As a probable consequence of high indoor air humidity conditions in unheated summer cottages in winter, dust samples contained threefold or higher concentrations of house dust and storage mites. Indoor humidity conditions thus more than compensated for lack of continuous supply of skin scales from human beings and an unfavorable low indoor air temperature. The uniform high mite exposure in summer cottages is likely to imply disease deterioration in patients already allergic to mites. [ABSTRACT FROM AUTHOR]

Sensitization to house dust mites, storage mites and other common inhalation allergens was studied in 144 farmers using SPT and RAST. The study population was selected from a random sample of 808 farmers and consisted of 47 persons who had declared themselves to suffer from asthma, 63 persons who had reported respiratory symptoms, and 34 healthy persons without respiratory symptoms. The most prevalent RAST was towards storage mites and was found in 17% of farmers who suffered from asthma and was estimated to occur in 5% of the random sample of farmers. A positive RAST to house dust mites was found in 17% of farmers who reported to suffer from asthma. Sensitization to pollens, animal dander and grain species was rare. A positive RAST to moulds was not found. There was a strong association between a positive RAST to house dust mites and a positive RAST to storage mites (odds ratio 21.0). A positive RAST to storage mites was significantly associated with living in a dwelling in the past which was recalled as damp (odds ratio 4.9). A high number of house dust mites was found in nearly all dwellings (median count 10,8 mites/0.1 g dust) and a high number of storage mites was found in some dwellings. This study suggests that in humid and temperate regions of Europe, allergy to storage mites in farmers is not caused exclusively by occupational exposure but damp housing conditions and indoor exposure to storage mites may also be important. [ABSTRACT FROM AUTHOR]

The pneumolysin ( ply) gene is widely used as a target in PCR assays for Streptococcus pneumoniae in respiratory secretions. However, false-positive results with conventional ply-based PCR have been reported. The aim here was to study the performance of a quantitative ply-based PCR for the identification of pneumococcal lower respiratory tract infection (LRTI). In a prospective study, fibreoptic bronchoscopy was performed in 156 hospitalized adult patients with LRTI and 31 controls who underwent bronchoscopy because of suspicion of malignancy. Among the LRTI patients and controls, the quantitative ply-based PCR applied to bronchoalveolar lavage (BAL) fluid was positive at ≥103 genome copies/mL in 61% and 71% of the subjects, at ≥105 genome copies/mL in 40% and 58% of the subjects, and at ≥107 genome copies/mL in 15% and 3.2% of the subjects, respectively. Using BAL fluid culture, blood culture, and/or a urinary antigen test, S. pneumoniae was identified in 19 LRTI patients. As compared with these diagnostic methods used in combination, quantitative ply-based PCR showed sensitivities and specificities of 89% and 43% at a cut-off of 103 genome copies/mL, of 84% and 66% at a cut-off of 105 genome copies/mL, and of 53% and 90% at a cut-off of 107 genome copies/mL, respectively. In conclusion, a high cut-off with the quantitative ply-based PCR was required to reach acceptable specificity. However, as a high cut-off resulted in low sensitivity, quantitative ply-based PCR does not appear to be clinically useful. Quantitative PCR methods for S. pneumoniae using alternative gene targets should be evaluated. [ABSTRACT FROM AUTHOR]

A birth cohort, comprising 4089 children, was followed. Information on exposures was obtained shortly after birth, and episodes of wheezing were recorded when the infants were 1 and 2 y of age. In a nested case-control study, 181 infants were enrolled, who had three or more reported episodes of wheezing after 3 mo of age combined with either use of inhaled steroids or symptoms of bronchial hyper-reactivity, and 359 age-matched controls. Home inspections were performed during the winter following enrolment, and indoor conditions were measured. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were calculated. The OR for recurrent infant wheezing associated with signs of dampness reported prospectively by parents was 1.4 (0.9–2.2), and the OR for observed signs of dampness at home inspections was 1.6 (1.0–2.5). A trend was found in the risk of recurrent wheezing in relation to the number of indicators of dampness: OR 1.3 (0.8–2.2) for one sign of dampness and OR 2.7 (1.3–5.4) for three or more signs of dampness. Newly painted surfaces in the child's bedroom was associated with an increased OR for recurrent wheezing: 1.7 (1.3–2.6). Indicators of dampness, as well as recently repainted interior surfaces, appear to be associated with recurrent infant wheezing, with a strengthened effect of combined indoor exposures. [ABSTRACT FROM AUTHOR]

This study was conducted to examine the impact of building characteristics and indoor air quality on recurrent wheezing in infants. We followed a birth cohort (BAMSE) comprising 4089 children, born in predefined areas of Stockholm, during their first 2 years of life. Information on exposures was obtained from parental questionnaires when the children were 2 months and on symptoms and diseases when the children were 1 and 2 years old. Children with recurrent wheezing, and two age-matched controls per case, were identified and enrolled in a nested case–control study. The homes were investigated and ventilation rate, humidity, temperature and NO2 measured. We found that living in an apartment erected after 1939, or in a private home with crawl space/concrete slab foundation were associated with an increased risk of recurrent wheezing, odds ratio (OR) 2.5 (1.3–4.8) and 2.5 (1.1–5.4), respectively. The same was true for living in homes with absolute indoor humidity >5.8 g/kg, OR 1.7 (1.0–2.9) and in homes where windowpane condensation was consistently reported over several years, OR 2.2 (1.1–4.5). However, air change rate and type of ventilation system did not seem to affect the risk. In conclusion, relatively new apartment buildings, single-family homes with crawl space/concrete slab foundation, elevated indoor humidity, and reported wintertime windowpane condensation were associated with recurrent wheezing in infants. Thus, improvements of the building quality may have potential to prevent infant wheezing. Our results show that different building-related exposures seem to have a major impact on children's health, and that improvement of the building structure may prevent infant wheeze, one of the most common causes of hospital admissions in early childhood. To improve the ventilation by increased air change rate may not be sufficient to create a healthy indoor environment. A poorly balanced ventilation system in the building might create conditions that increase the risks for recurrent wheeze in young children, and an improved air change rate may also result in increased levels of outdoor-generated pollutants indoors. Thus, healthy indoor environments require a comprehensive view of the building, including accuracy in planning, construction, and maintenance. [ABSTRACT FROM AUTHOR]