Contributory and exacerbating roles of gaseous ammonia and organic dust in the etiology of atrophic rhinitis. (1/73)

Pigs reared commercially indoors are exposed to air heavily contaminated with particulate and gaseous pollutants. Epidemiological surveys have shown an association between the levels of these pollutants and the severity of lesions associated with the upper respiratory tract disease of swine atrophic rhinitis. This study investigated the role of aerial pollutants in the etiology of atrophic rhinitis induced by Pasteurella multocida. Forty, 1-week-old Large White piglets were weaned and divided into eight groups designated A to H. The groups were housed in Rochester exposure chambers and continuously exposed to the following pollutants: ovalbumin (groups A and B), ammonia (groups C and D), ovalbumin plus ammonia (groups E and F), and unpolluted air (groups G and H). The concentrations of pollutants used were 20 mg m-3 total mass and 5 mg m-3 respirable mass for ovalbumin dust and 50 ppm for ammonia. One week after exposure commenced, the pigs in groups A, C, E, and G were infected with P. multocida type D by intranasal inoculation. After 4 weeks of exposure to pollutants, the pigs were killed and the extent of turbinate atrophy was assessed with a morphometric index (MI). Control pigs kept in clean air and not inoculated with P. multocida (group H) had normal turbinate morphology with a mean MI of 41.12% (standard deviation [SD], +/- 1. 59%). In contrast, exposure to pollutants in the absence of P. multocida (groups B, D, and F) induced mild turbinate atrophy with mean MIs of 49.65% (SD, +/-1.96%), 51.04% (SD, +/-2.06%), and 49.88% (SD, +/-3.51%), respectively. A similar level of atrophy was also evoked by inoculation with P. multocida in the absence of pollutants (group G), giving a mean MI of 50.77% (SD, +/-2.07%). However, when P. multocida inoculation was combined with pollutant exposure (groups A, C, and E) moderate to severe turbinate atrophy occurred with mean MIs of 64.93% (SD, +/-4.64%), 59.18% (SD, +/-2.79%), and 73.30% (SD, +/-3.19%), respectively. The severity of atrophy was greatest in pigs exposed simultaneously to dust and ammonia. At the end of the exposure period, higher numbers of P. multocida bacteria were isolated from the tonsils than from the nasal membrane, per gram of tissue. The severity of turbinate atrophy in inoculated pigs was proportional to the number of P. multocida bacteria isolated from tonsils (r2 = 0.909, P < 0.05) and nasal membrane (r2 = 0.628, P < 0.05). These findings indicate that aerial pollutants contribute to the severity of lesions associated with atrophic rhinitis by facilitating colonization of the pig's upper respiratory tract by P. multocida and also by directly evoking mild atrophy.  (+info)

Epistaxis: study of aetiology, site and side of bleeding. (2/73)

The present study comprises 300 cases of epistaxis. The analysis of these cases revealed a higher incidence in young males. Unilateral bleeding was seen in almost 60% each of indoor and outdoor cases. Litte's area was the most common site responsible for epistaxis in 28.8% of the indoor and 26.2% of the outdoor patients. Hypertension was the most common systemic cause among indoor patients (62.2%) and sickle cell disorder among the outdoor patients (37.5%). Atrophic rhinitis with myiasis was the local cause of epistaxis in maximum (27%) of the indoor patients and traumatic epistaxis was the commonest cause (33%) among outdoor patients-fingernail trauma in 75.9% of them. Idiopathic epistaxis contributed for 16.5% indoor and 26.1% of outdoor cases. Intractable epistaxis was seen in one case following accidental facial trauma.  (+info)

Changes in the nasal mucosa after exposure to copper salt dust. A preliminary report. (3/73)

Ten mental workers with varying exposure to complex copper salts to dust form, six other metal workers not exposed, and nine construction workers in other occupational categories, also unexposed to the salts, were compared with respect to history and mucosal changes in the nose. There were subjective symptoms of metal dust exposure in the group exposed to the copper salts. Suspected early atrophic changes in the mucous membranes were noted in subjects exposed for long periods of time. Protective equipment in the form of breathing masks should be used in this type of work unless moistening or a surface finish on the copper sheeting is capable of preventing the release of dust.  (+info)

Characterization and comparison of Pasteurella multocida strains associated with porcine pneumonia and atrophic rhinitis. (4/73)

One hundred and fifty-eight porcine strains of Pasteurella multocida, recovered primarily from cases of pneumonic pasteurellosis or progressive atrophic rhinitis (PAR) in England and Wales, were characterized by determination of their capsular types, presence or absence of the toxA gene and molecular mass heterogeneity of the heat-modifiable (OmpA) and porin (OmpH) proteins. Eighteen groups (clones) of strains were identified on the basis of specific combinations of capsular type, toxA status and outer-membrane protein (OMP)-type. The data provided evidence that different subpopulations of P. multocida are responsible for pneumonia and PAR in pigs. The majority (88 %) of cases of pneumonia were associated exclusively with non-toxigenic capsular type A strains of OMP-types 1.1, 2.1, 3.1 and 5.1 and capsular type D isolates of OMP-type 6.1. These strains were recovered from widespread geographical locations within England and Wales over a 12-year period and represented mostly single sporadic cases. The association of a small number of P. multocida variants with the majority of cases of porcine pneumonia suggests that these strains are not opportunistic pathogens of low virulence but represent primary pathogens with a relatively high degree of virulence. In contrast, the majority (76 %) of cases of PAR were associated with toxA-containing capsular type D strains of OMP-type 4.1 and capsular type A and D strains of OMP-type 6.1. Toxigenic capsular type A strains associated with PAR and non-toxigenic capsular type A strains associated with pneumonia represent distinct subpopulations of P. multocida that can be differentiated by their OMP-types. The association of capsular types A and D with strains of the same OMP-types, and the absence and presence of the toxA gene in strains of the same OMP-types, suggest that horizontal transfer of capsular biosynthesis and toxA genes has occurred between strains representing certain subpopulations of P. multocida.  (+info)

Use of single-enzyme amplified fragment length polymorphism for typing Pasteurella multocida subsp. multocida isolates from pigs. (5/73)

Single-enzyme amplified fragment length polymorphism (SE-AFLP) analyses were used to differentiate 97 isolates of porcine Pasteurella multocida subsp. multocida. The strains, isolated from animals with pneumonia, rhinitis, and septicemia, were classified as capsular types A, D, and F. SE-AFLP showed a discriminatory index of 0.87 and identified 18 different profiles.  (+info)

Use of ELISA to detect toxigenic Pasteurella multocida in atrophic rhinitis in swine. (6/73)

The use of an enzyme-linked immunosorbent assay (ELISA) as a means of detecting dermonecrotoxin-producing strains of Pasteurella multocida was investigated. The assay was evaluated as a means to identify toxigenic P. multocida isolates recovered from nasal secretions of swine with atrophic rhinitis. The sensitivity and specificity of the ELISA for detecting dermonecrotoxin-producing P. multocida strains were compared to those of mouse-inoculation and cytotoxicity assays. The ELISA was highly sensitive and more specific than animal inoculation or tissue culture assay and is thus a more effective method for screening swine herds for the presence of toxigenic strains of P. multocida. The ELISA is a rapid, effective, economical way to identify toxigenic P. multocida isolates.  (+info)

Power microdebrider-assisted modification of endoscopic inferior turbinoplasty: a preliminary report. (7/73)

BACKGROUND: In this article, microdebrider-assisted modification of endoscopic inferior turbinoplasty is described. It has the advantage of superior visualization during elevation of the mucosal flap and allows precise tailoring of the resection to the needs of patients. METHODS: From November 2001 to December 2002, 29 patients with chronic hypertrophic rhinitis treated with power endoscopic inferior turbinoplasty were available for follow-up examinations. Questionnaires and rhinomanometric studies were performed for subjective and objective evaluations. These patients were followed up for an average of 15.3 months after the operation. RESULTS: The overall improvement in nasal obstruction was 91% in our study. Twenty-two patients received rhinomanometric studies 1 week preoperatively and 2 months postoperatively. The average nasal airflow was increased by 187 ml/min. In addition, complete relief of headaches was achieved. But the remission rates of persistent rhinorrhea and post-nasal dripping were less significant, at about 58% and 54%, respectively. Atrophic change and permanent synechiae had not yet been observed. CONCLUSIONS: Power endoscopic turbintoplasty is a safe, simple, and effective method for the treatment of chronic hypertrophic rhinitis. It is especially handy in adjunct to endoscopic septoplasty or sinosurgery, and appears to provide a surgical choice of a minimally invasive technique. However, further study with a prospective design is needed to strengthen the evidence.  (+info)

Survival of toxigenic Pasteurella multocida in aerosols and aqueous liquids. (8/73)

The survival of toxigenic Pasteurella multocida in air and liquids was studied to identify possible risk factors in the etiology of atrophic rhinitis. In aerosols, at low relative humidity (28%), the viability of toxigenic P. multocida 5 min after aerosolization was at least 22% of its initial value. Viability at low relative humidity declined to 8% after 45 min. Viability at high relative humidity (79%) was 69% after 5 min and declined to 2% after 45 min. Survival of toxigenic P. multocida in liquids depended on storage and constituents in the liquid. Toxigenic P. multocida became nonculturable 1 to 14 days after inoculation in water and artificial seawater, depending on the storage temperature. Toxigenic P. multocida stored at 37 degrees C could be detected for up to 6 days in pig slurry and more than 36 days in Bacto Tryptose broth and nasal lavages. However, in Bacto Tryptose broth and nasal lavages stored at 4 degrees C, P. multocida was detected for up to 14 days whereas at 15 and 37 degrees C it was detected for more than 49 days. These results suggest that aerosols and fomites can play a role in the transmission of atrophic rhinitis.  (+info)