[A relapse of acute bird-related hypersensitivity pneumonitis due to the use of a feather duvet by a housemate]

In December 2007, a 78-year-old woman was admitted to our hospital complaining of cough and low-grade fever for 1 month. We performed various medical tests and diagnosed acute hypersensitivity pneumonitis. We suspected that the cause of illness was the prolonged use (10 years) of a feather duvet. She was treated with corticosteroids and was advised to avoid using feather duvets. This treatment improved her symptoms. However, she relapsed after 1 year. She had never used a feather duvet since the last admission, but her housemate used a feather duvet in the same room during winter. Bronchoalveolar lavage revealed lymphocytosis. Specific antibodies against pigeon and budgerigar-dropping extracts were present in her serum. On the basis of these findings, we diagnosed acute bird-related hypersensitivity pneumonitis. This condition is rarely caused by indirect exposure. Therefore, we reiterate the significance of obtaining of a detailed medical history to identify relevant antigens.

Bird fancier's lung which developed in a pigeon breeder presenting organizing pneumonia

Bird fancier's lung (BFL) is one of the most common types of hypersensitivity pneumonitis. We report a rare case of acute-on-chronic bird fancier's lung that developed in a pigeon breeder and presented subpleural curvilinear shadow and ground glass opacity on high-resolution computed tomography (HRCT) of the chest. The results of surgical lung biopsy showed mainly intraalveolar organization and alveolitis in addition to the pattern of usual interstitial pneumonia with centrilobular fibrosis. Examination of bronchoalveolar lavage (BAL) fluid revealed an increase in lymphocytes. The results of immunoglobulin (Ig) G and IgA antibodies against pigeon dropping extracts were positive in sera and BAL fluid. Consequently, the patient was diagnosed as having BFL. Avoidance of pigeons and corticosteroid therapy led to rapid improvement.

[Case of acute bird fancier's lung caused by a yellow-shouldered Amazon bird associated with lung cancer]

A 69-year-old man was admitted to our hospital complaining of generalized weakness and cough for one month. Chest computed tomography (CT) demonstrated bilateral ground-glass opacities and a nodule in right S6 about 11mm in diameter with multiple mediastinal lymph node swellings. After admission the patient's symptoms improved without therapy and examination of the bronchoalveolar lavage fluid (BALF) and transbronchial lung biopsy (TBLB) revealed findings compatible with acute hypersensitivity pneumonitis. We did not consider that the acute hypersensitivity was caused by the patient's Amazon bird, because he had been breeding them for 40 years. However after obtaining a careful history, it became clear that close and frequent contact with the bird had occurred for the first time in the previous year. On the basis of the anti-bird excreta antibody found in the patient's serum and BALF, we diagnosed this case as a case of acute bird fancier's lung caused by the yellow-shouldered Amazon bird. We diagnosed the nodule in right S6 as lung adenocarcinoma by a thoracoscopic lung biopsy, and performed lower lobe lobectomy. We considered that the mediastinal lymph node swellings were caused by hypersensitivity pneumonitis.

Effect of cigarette smoking on the development of murine chronic pigeon breeder's lung. The difference between a short-term and a long-term exposure

Previous reports suggested that cigarette smoke had a protective effect of on the development of hypersensitivity pneumonitis (HP). However, smoking rate in chronic pigeon breeder's lung (PBL) seemed to be high in our clinical experiences. We developed a murine model of PBL by intranasal instillation with pigeon dropping extracts (PDE) for 4 weeks (short-term exposure) and 17 weeks (long-term exposure) to investigate the effect of cigarette smoke on disease processes. In this model, lung inflammation associated with the production of anti-PDE antibodies and antigen dependent lymphocyte proliferation was induced. Long-term exposure to PDE without cigarette smoking resulted in an increase in lung weight/body weight ratio, total cell number in bronchoalveolar lavage (BAL) fluid, and content of hydroxyproline in the lung compared to shortterm exposure. After a short-term exposure, cigarette smoke lessened the lymphocytosis in BAL fluid, and lymphocyte proliferation. On the other hand, after a long-term exposure cigarette smoke increased lung hydroxyproline. These results suggest that a short-term cigarette smoking attenuates lung inflammation, but a long-term cigarette smoking enhances lung inflammation with fibrosis.

[Three cases of chronic bird fancier's lung associated with the use of feather bedclothes]

We report here 3 cases of chronic bird fancier's lung diagnosed immunologically using antibodies to pigeon dropping extract. None of the patients were bird fanciers but had indirect exposure to birds in their living environment, and had been using feather-filled duvets or pillows for a long time. Two of 3 cases were positive for environmental provocation tests and 2 cases had pathological findings of hypersensitivity pneumonitis such as multinucleated giant cells and non-necrotizing epithelioid cell granulomas. One case was resistant to steroid therapy alone and was successfully treated by coadministration of prednisolone and cyclosporin A. Another case was treated by steroid alone but died of acute exacerbation of unknown cause. These cases suggest that not only feathers but two or more kinds of bird-related antigens were involved in the sensitization immunology and development of bird fancier's disease, and that clinicians should perform thorough history taking with environmental surveillance relevant to birds.

A clinical study of hypersensitivity pneumonitis presumably caused by feather duvets

BACKGROUND

Bird fancier's lung (BFL) is a type of hypersensitivity pneumonitis induced by the inhalation of bird-related antigens. The BFL induced by feathers is difficult to diagnose because feathers are generally unrecognized as a causative antigen.

OBJECTIVE

To determine the clinical features of BFL presumably induced by feather duvets (feather duvet lung) to provide clues for diagnosis.

METHODS

We performed a retrospective review of the medical records of patients with feather duvet lung evaluated between April 1, 2000, and June 30, 2003, at the Tokyo Medical and Dental University Hospital in Japan.

RESULTS

Seven patients with feather duvet lung were included in this study; 4 patients had acute disease and 3 had chronic BFL. Duration of contact with feather duvets was 1 month to 10 years. Serum KL-6 and surfactant protein D levels were elevated in all the patients. Specific antibodies against avian antigens were positive in acute BFL but negative in chronic BFL. Antigen-induced lymphocyte proliferation in peripheral blood or bronchoalveolar lavage cells was positive in all the patients. The diagnosis was confirmed by an environmental or inhalation provocation test.

CONCLUSIONS

Feather duvets can induce acute and chronic BFL. Physicians should be aware of feather duvets as a cause of BFL because feather duvets are becoming more prevalent.

[Bird fancier's lung--an allergic alveolitis]

BACKGROUND

Bird fancier's lung is globally the second most frequent cause of extrinsic allergic alveolitis.

MATERIAL

For many years, the patient had influenza-like symptoms and developed progressing pulmonary fibrosis. Over a period of 10 years she had been exposed to up to 43 birds in the house at any one time and serum precipitates against avian proteins had been found. After sanitation of the house of birds and avian proteins, the pulmonary function has not deteriorated further in 5 years.

INTERPRETATION

A thorough environmental history is essential in the diagnosis of extrinsic allergic alveolitis; at an earlier stage it would have made us think about this possible etiological factor. This could have prevented the development of permanent pulmonary fibrosis if the patient had been advised to avoid further exposure to antigens. There should be greater awareness of this disease among general practitioners as well as among chest consultants in Norway.

Pheasant rearer's lung

A 47-year-old gamekeeper presented with an 8 month history of variable breathlessness, cough and clinical features of severe interstitial lung disease. Open lung biopsy showed an extrinsic allergic alveolitis, which we believe related to his work rearing pheasants. Initially he was resistant, despite advice, to changing his occupation but subsequently, although ceasing exposure to pheasants and beginning treatment with corticosteroids, his disease progressed to the point where he developed respiratory failure and was referred for lung transplantation. Sadly, he died of progressive respiratory failure and cor pulmonale complicated by bronchopneumonia before this could be achieved.

[A case of acute hypersensitivity pneumonitis caused by contact with budgerigars (bird-breeder's lung)]

A 58-year-old woman was admitted to our hospital for repeated episodes of dry cough, low-grade fever, and gradual development of dyspnea on exertion. Chest computed tomography showed diffuse ground-glass opacities in both lung fields. Bronchoalveolar lavage fluid (BALF) showed an increased number of lymphocytes, and transbronchial lung biopsy revealed alveolitis and epithelioid cell granuloma. The acute onset and the patient's living environment suggested summer-type hypersensitivity pneumonitis. However, anti-Trichosporon antibody was negative and a definitive diagnosis could not be made. The patient's condition improved with corticosteroid treatment and, after discharge from the hospital, she moved to a new home. The following year, however, her symptoms returned, and she was readmitted to our hospital. Recurrence of the disease despite the change in environment ruled out summer-type hypersensitivity pneumonitis. Given the patient's history of budgerigar breeding five years earlier, bird breeder's lung was suspected. Anti-bird excreta antibody found in the patient's serum and BALF, along with a positive lymphocyte stimulation test against pigeon serum, strongly suggested an acute onset of bird breeder's lung. We report a rare case of acute bird breeder's lung with radiologic findings of ground-glass opacities, a one-year disease-free period and an acute relapse.

[A case of acute bird fancier's lung caused by feather duvet]

A 57-year-old woman was admitted to our hospital because of cough and low-grade fever for 2 months and shortness of breath for 2 weeks. She had raised two budgerigars for the last 15 years and had been using a feather duvet for one year. A chest radiograph showed diffuse ground-glass opacities in both lung fields, and a chest CT scan showed centrilobular micronodules and ground-glass opacities. Bronchoalveolar lavage (BAL) revealed a marked increase in lymphocytes, and a transbronchial lung biopsy (TBLB) specimen showed alveolitis due to the infiltration of mononuclear cells. Since she had specific antibodies against pigeon and budgerigar dropping extracts and her peripheral blood lymphocytes proliferated on addition of pigeon serum, she was diagnosed as having bird fancier's lung (BFL). She was treated with steroids, which brought about a marked improvement. After she visited her husband who had been hospitalized where a feather duvet was provided for each patient, both subjective and objective findings deteriorated. This deterioration was preventable when she wore a protective mask for micro-dust while visiting her husband. The feather duvets seemed to induce acute BFL in this case, though raising budgerigars may well be related to her sensitization with bird-related antigens.

Feather duvet lung

BACKGROUND

Bird fancier's lung (BFL) is a type of hypersensitivity pneumonitis, which is induced by inhalation of bird related antigens. The diagnosis of BFL induced by feathers is difficult because feathers are generally not recognized as a causative antigen of BFL. We report a female case of chronic BFL presumably due to a feather duvet, which presents as pulmonary fibrosis.

CASE REPORT

A 73 year-old woman presented with exertional dyspnea for the last three years. She had raised two pigeons for three years (1971-1973) in her forties and had been using a feather duvet for the last eight years (1992-2000). A chest X-ray showed reticular infiltrates in the both peripheral lung field and an HRCT scan showed scattered consolidation, micronodules, and peribronchial ground-glass opacities. Lymphocyte proliferation to the feather antigen was positive and inhalation provocation test using a bird antigen was also positive. Thoracoscopic biopsy specimens showed organization, cholesterol clefts, alveolitis around terminal and respiratory bronchioles--all of which are consistent with chronic hypersensitivity pneumonitis. Clinical findings have spontaneously improved after she stopped using her feather duvet.

CONCLUSIONS

Feather beds including duvets, pillows, and cushions are now popular all over the world. Physicians should be aware of feathers as a cause of BFL since this induction seems to be more prevalent.

Cockatiel-induced hypersensitivity pneumonitis

Diagnosing an environmental or occupationally related pulmonary disorder often involves a process of elimination. Unlike commonly diagnosed conditions in other specialties, a cause-and-effect relationship may be implied, yet other factors such as temporality and biologic plausibility are lacking. Our patient was referred with a suspected work-related pulmonary disorder. For several years, she had suffered with dyspnea on exertion and repeated flulike illnesses. She worked at an automobile repair garage that performed a large number of emission tests, and there was concern that her workplace exposures were the cause of her symptoms. After a careful review of her history, physical examination, and laboratory testing, we came to the conclusion that she had hypersensitivity pneumonitis related to pet cockatiels in her home. Clinical points of emphasis include the importance of a complete environmental history and careful auscultation of the chest when performing the physical examination. In addition, we encountered an interesting physical diagnostic clue, a respiratory sound that assisted with the eventual diagnosis.

Subacute hypersensitivity pneumonitis in an HIV infected patient receiving antiretroviral therapy

Abnormal pulmonary immune response to various antigens can lead to hypersensitivity pneumonitis. This disease has not previously been reported in HIV infected patients. This case report describes an HIV infected woman who developed subacute hypersensitivity pneumonitis in response to bird exposure. The disease manifested itself only after the patient experienced an improvement in her CD4 positive T lymphocyte count secondary to antiretroviral therapy. This case emphasises the need to consider non-HIV associated diseases in patients with HIV and suggests that diseases in which host immune response plays an essential role in pathogenesis may become more prevalent in HIV infected patients receiving effective antiretroviral therapy.

A custodian cured the doctor!

Opinions expressed in commentaries are those of the authors and not necessarily those of the American Academy of Pediatrics or its Committees. Commentaries are not peer-reviewed.

A hazard of Christmas: Bird Fancier's Lung and the Christmas tree

A lady with alveolitis due to her budgerigar developed recurrent symptoms when exposed to allergen left on her artificial Christmas tree.

[Asthmatic child without asthma]

Two boys aged 13 and 7 years, displayed chronic coughing, dyspnoea on exertion, anorexia, weight loss, and fatigue. At first a diagnosis of asthma was made. However, a correct interpretation of anamnestic and clinical features, laboratory findings and radiographic results led to the diagnosis of 'pigeon breeder's disease' in both cases. Both patients recovered after drug treatment and avoidance of re-exposure to pigeon antigen.

[An elderly woman with chronic pigeon-breeder's disease]

A 64-year-old woman had been feeding more than 60 pigeons in a coop in her back yard for 35 years. Diffuse reticulonodular shadows were found on a chest radiograph obtained as part of an annual check-up eight years before admission to the hospital. She was given a tentative diagnosis of idiopathic pulmonary fibrosis and was observed. She was admitted to our hospital because she noticed dry coughing and shortness of breath. A chest CT scan revealed segmentally distributed honeycombing and bronchi-bronchioloectasis. Tests for IgA and IgG antibodies to extracts of pigeon droppings in serum samples and in samples of bronchoalveolar lavage fluid were strongly positive, as were tests for lymphocyte blastogenic responses to samples of pigeon serum Examination of lung-biopsy specimens obtained by video-assisted thoracoscopic surgery revealed bronchiolitis, alveolitis, and honeycombing in a centrilobular distribution. The patient was given a diagnosis of pigeon-breeder's disease. Chronic hypersensitivity pneumonitis without acute episodes might be misdiagnosed as idiopathic interstitial pneumonia or bronchiectasis, as happened in this case. The possibility of chronic hypersensitivity pneumonitis should be considered when patients are suspected to have pulmonary fibrosis. It is important to obtain the detailed information on past or current avian contact, working history, and the home environment.

Feather mites are potentially an important source of allergens for pigeon and budgerigar keepers

BACKGROUND

Previous studies on allergy to feathers have not addressed whether organisms living on feathers (mites, lice, moulds) are a source of allergens.

OBJECTIVE

To investigate whether feather mites produced allergens of clinical relevance to bird keepers.

METHODS

We examined serum IgE responses of 96 pigeon breeders to an extract of feather mites from pigeons (predominantly Diplaegidia columbae), using Western blotting, specific IgE assay using AlaSTAT EIA and RAST inhibition.

RESULTS

Feather mites are a major source of soluble proteins derived from feathers, accounting for up to 10% of the total weight of the feather. Forty-three sera had a negative score (0) for anti-feather mite IgE, 27 were weakly positive (1-2) and 26 had strongly positive scores (3-4). Fewer pigeon breeders with scores > or = 3 were asymptomatic than those with negative scores (12 versus 40%), more had late onset symptoms (with or without early onset symptoms: 77% versus 44%) and had IgE antibody against house dust mite (89% versus 23%). Western blotting of eight sera against the extract of Diplaegidia columbae revealed 20 IgE-binding components ranging from 22 to 200 kDa. A high diversity of components was recognized by each serum: arithmetic mean 7 (range 2-14). RAST inhibition indicated feather mites had species-specific epitopes as well as ones that cross-reacted with Dermatophagoides pteronyssinus.

CONCLUSION

Strongly-positive AlaSTAT scores to pigeon feather mite were associated with allergic symptoms of late onset in pigeon breeders. We conclude that feather mites are a major source of clinically-relevant allergens for pigeon breeders.

Hypersensitivity pneumonitis in a raptor handler and a wild bird fancier

BACKGROUND

Hypersensitivity pneumonitis has been associated with a variety of antigens in various settings. We have recently encountered one case of hypersensitivity pneumonitis from owl droppings and another case from a wild Moluccan cockatoo.

OBJECTIVE

It is important to alert physicians to the possibility of hypersensitivity pneumonitis when dealing with wildlife workers and wild bird fanciers.

METHOD

A report of two cases with progress and response to therapy.

RESULTS

Clinical and serologic information are of value in the diagnosis of hypersensitivity pneumonitis due to birds and avoidance is the optimal approach.

CONCLUSION

There are many raptor handlers and wild bird fanciers across the United States and the world. Given the incidence of hypersensitivity pneumonitis in pigeon breeders, this may herald a new variant of allergic disease among wildlife workers and wild bird fanciers.

Hypersensitivity pneumonitis associated with home ultrasonic humidifiers

We describe five patients with hypersensitivity pneumonitis (HP) that was related to using home ultrasonic humidifiers. All patients had micronodular infiltrates on their chest radiograph, and their lung biopsy specimens revealed alveolitis with or without epithelioid cell granulomas. Challenge tests were performed on two patients with the humidifier water and three patients using the humidifier. All patients tested exhibited a positive response. Tests for precipitating antibodies against an extract of the humidifier water gave strongly positive reactions in all patients tested. Precipitins to Cephalosporium acremonium and Candida albicans were also present in all cases, whereas precipitins to thermophilic actinomycetes were not detected. Although cultures of the water grew a variety of fungal and bacterial organisms, thermophilic actinomycetes could not be detected. These findings suggest that thermophilic organisms may not be the causative antigens of HP associated with ultrasonic humidifiers. All five patients had an increase in the bronchoalveolar lavage (BAL) lymphocytes that were predominantly CD4+ lymphocytes. The T helper cell count (CD4) to suppressor T cell count (CD8) ratio was significantly higher than that observed in summer-type HP, and lower than that observed in bird fancier's lung, indicating that the phenotypes of the BAL lymphocytes may vary with the type of HP.

[Capability of clinical and laboratory findings to predict the grade of fibrosis and the diagnosis in diffuse interstitial lung diseases]

Our objective was to assess the capacity of clinical and laboratory information to predict findings in the lung biopsy in interstitial lung diseases (ILD). We studied 121 patients with ILD as a cohort recruited in our institute from 1983 to 1987 with the diagnosis of hypersensitivity pneumonitis (HP) and usual interstitial pneumonia (UIP). Histologic diagnosis (HP vs UIP) and degree of fibrosis (< 50% of the biopsy surface vs > or = 50%) were used as the gold standard to compare a series of clinical and laboratory variables in the initial assessment. We used a stepwise logistic regression model to predict the biopsy results. The model was calculated in half of the patients selected by random sampling, and the calculated model was tested in the other half of the patients. Variables found to predict degree of fibrosis were (with relative risk RR and 95% confidence interval): a radiographic pattern of honeycombing (RR 5.0 from 0.9-29), digital clubbing (RR 8 from 1.4-48) and gender (RR 2.9 from 0.4-20). This model classified correctly 72% of the biopsies, with a sensitivity of 0.38, a specificity of 0.85 and a kappa of 0.25 +/- 0.19 (p = 0.17 NS). For histologic diagnosis (NIU vs NH), the model included gender (RR 6.6, 1.3-33), honeycombing (RR 1.6, from 0.4-6.0), digital clubbing (RR 4.6, from 1.2-18), and vital capacity expressed as percent of predicted (RR 0.96, from 0.92-1.00).(ABSTRACT TRUNCATED AT 250 WORDS)

Hypersensitivity pneumonitis due to native birds in a bird ringer

A bird fancier who had only been exposed to native birds, mostly owls, developed a sever hypersensitivity pneumonitis with a very insidious onset.

[The mechanisms of allergic damage to the bronchoalveolar apparatus in poultry plant workers]

Specific and non-specific mechanisms of defense and damage were studied in 296 poultry breeders, 20 of them were diagnosed the exogenic allergic alveolitis (EAA), the so-called "breeder's lung". The following characters were found: an increase in the blood leucocyte phagocytic activity, non-specific neutrophilic damage values, specific neutrophilic damage and specific lymphocyte damage values, lactate dehydrogenase activity, circulated immune complexes level, immunoglobulins A and M in blood serum in breeders with EAA. Only breeders with service of 1-5 and 11-15 years have shown no changes in non-specific neutrophilic damage values. A decrease in the T-lymphocyte content, theophylline-sensitive and theophylline-stable lymphocyte subpopulations in blood serum of breeders with EAA were observed as well.

Experimental models of hypersensitivity pneumonitis

Experimental models of hypersensitivity pneumonitis are important tools for the study of the pathogenesis of this disease. In this paper we review the characteristics of the main animal models developed until now. The HP models in rats seem to be particularly appropriate for studying pigeon fancier's disease and the HP induced by chemicals, as well as for studying mediators of acute lesions induced by immunocomplexes. However, the HP models developed in rats are of less value in the evaluation of other aspects of the pathogenesis of this clinical entity in humans. The murine models of HP offer several advantages: the ease and simplicity of intranasal administration, the ability to produce acute and subacute pulmonary lesions similar to those found in humans, the possibility of reproducing lesions similar to those of nonaffected exposed subjects and the possibility of pharmacologically modulating the process. Their disadvantages lie in the different pulmonary lymphocyte response and the difficulty in reproducing a model of chronic fibrosis. The HP models in rabbits are extraordinarily useful for evaluating the immunological mechanisms through which subjects repeatedly exposed to the antigen do not develop clinical manifestations. However, the rabbit has several immunological differences when compared to humans, and the effect of some immunomodulators in this animal is different. The models of HP in guinea-pigs have as advantages the ease in handling the animals, the possibility of pharmacological manipulation, and the ability to induce an acute phase that is very similar to that observed in humans. The drawback, however, is the low lymphocyte response and the striking eosinophilic reaction that contrast with the bronchoalveolar data found in HP in humans. In conclusion, there is no ideal model to reproduce all the findings observed in humans, suggesting that the experimental animal and the method of developing HP should be selected on the basis of concrete research aims.

[Pigeon coryza--ornithosis--pigeon breeder's lung]

The published informations on the entities pigeon coryza and ornithosis are reviewed. On the basis of own experiences and experimental data obtained in the Landesveterinäruntersuchungsamt Koblenz, pigeon coryza apparently is a symptom rather than a clearly defined disease. Finally pigeon breeder's lung is discussed in front of the background of own observations and recommendations to be of allergic origin.

Pigeon breeders' lung--the effect of loft litter materials on airborne particles and antigens

An Andersen sampler was used to collect different sized fractions of airborne dust within pigeon lofts. Antigens associated with pigeon breeders' lung were then measured using an ELISA technique. Levels of soluble antigen in the 0.5-5 microns range correlated significantly with airborne particle concentrations in the same range, determined by particle size analysis. However, antigenic material was not soley confined to the 0.5-5 microns fraction and was detected in particles up to 11 microns in diameter. Using both particle size analysis and ELISA in local pigeon lofts revealed significantly increased particles (up to x 50) and antigens (up to x 10) in some lofts employing litter materials to dehydrate voided pigeon droppings, compared with lofts cleaned regularly with no litter agent. Paradoxically, ventilation did not influence particle or antigen concentrations under static conditions or during loft cleaning. The settling rate of loft dusts correlated significantly with that of the litter used, suggesting litter particles were a carrier for soluble pigeon dropping components, but differences in particle numbers generated from the litters and litter/dropping combinations showed that an interaction between voided droppings and litter agents had occurred. A change from litter systems to regular cleaning was undertaken in two lofts, resulting in a marked decrease in respirable particles and antigens.

[A case of pigeon breeder's disease]

A 73-year-old woman developed dry cough and exertional dyspnea. She had been breeding pigeons for thirty years. Her serum showed positive precipitin reaction against pigeon serum. Furthermore the lymphocyte stimulation test against pigeon serum was positive. An X-ray film of the chest showed diffuse ground glass infiltrate, fine nodular shadows and reticular shadows. Histopathology revealed diffuse interstitial infiltration with mononuclear cells and occasional giant cell formation as well as granuloma formation in the bronchiole. The symptoms subsided after admission. From these results, this case was diagnosed as pigeon breeder's disease. She had the subacute form probably because of her old age and smoking. It could be that exacerbation of pneumonitis was caused by cessation of smoking in an attempt to alleviate the symptoms. This is the fifth case reported in Japan.

Pigeon breeders' disease: quantitative immunoelectrophoretic studies of pigeon bloom antigen

This study employed quantitative immunoelectrophoretic techniques, on sera from confirmed cases of pigeon breeders' disease (PBD), to investigate the antigenicity of a pigeon bloom extract, implicated as a sensitizing agent in this disease. On crossed immunoelectrophoresis the maximum number of antigenic components identified was 29 for the bloom compared to 10 for pigeon serum. A major component was shown to be closely related to pigeon IgA, and demonstrated partial crossreactivity to the pigeon IgG. This component also showed identity with the major component of a pigeon droppings extract, considered to be derived from intestinal IgA. Only trace amounts of serum albumin were detected and most other bloom components were not serum-related. Although greater overall antigenic similarity was found to pigeon droppings extract, at least three of the bloom components appeared to be specific. The bloom extract also contained a low amount of an alpha-techoic acid-like component, causing some non-specific reactivity. Pigeon feather dust or 'bloom', like pigeon droppings, is therefore a potent source of antigens associated with PDB--pigeon IgA being a major component of both antigens.

Allergens and irritants

The range of diseases caused by respiratory allergens and irritants is wide because they trigger different pathophysiological mechanisms. Surprisingly, though smoking promotes asthma it exerts the opposite effect on the development of extrinsic allergic alveolitis.

Time of exposure as a prognostic factor in avian hypersensitivity pneumonitis

Spirometric values were subsequently evaluated in 22 patients suffering from hypersensitivity pneumonitis caused by avian problems. First spirometric values were abnormal in 18/22 (82%) of patients. A restrictive pattern was observed in 16/22 (72%) of patients and an obstructive pattern in 6/22 (27%). The TLCO was reduced in all cases (12/12). Improvement or normalization of the respiratory function occurred 3.4 +/- 2.4 months after the avian contact had ceased. At the end of the follow-up, parameters were normal in 13/22 (59%) of patients. The restrictive pattern remained unchanged in 7/22 (32%), and the obstructive pattern persisted in 4/22 (18%) of the patients. The TLCO was normal in 6/12 (50%) of patients. Neither age nor treatment with corticosteroids (13 patients) had a significant influence upon the evolution of the lung function. However, total recovery or significant improvement was observed in 12/12 (100%) of patients who had been in contact with birds less than 2 years, in contrast to 6/10 (60%) of patients with more than 2 years of contact (P = 0.002).

[Extrinsic allergic alveolitis: apropos of a case in a child]

We present a young male (12 years) with low grade fever, weight loose, anorexia and progressive dyspnea. The clinical, roentgenological and pulmonary function pictures are close with interstitial pneumonitis. The patient had a pigeon loft on his house, thus we tried confirmed the diagnosis of extrinsic allergic alveolitis: pigeon breeder's lung. We believed at any patient age the pigeon breeder's lung must be considered in the differential diagnosis of interstitial pneumonitis. A good anamnesis will avoid unnecessary complementary test.

Immunoglobulin G4 in pigeon breeder's disease

Immunoglobulin G4 has previously been implicated in the pathogenesis of pigeon breeder's disease (PBD), a form of hypersensitivity pneumonitis associated with inhalation of pigeon antigens. We investigated the presence of IgG4 antibody to antigens in pigeon dropping extracts (PDE) in the lungs of pigeon breeders. Seven of these subjects had symptoms of PBD and eight others had no symptoms. IgG4 antibody to PDE was compared with IgG3 levels because both were relatively minor subclasses, but IgG3 is not considered reaginic whereas IgG4 is. An increase in IgG4 antibody relative to IgG3 would therefore be considered a selective increase and suggest a role for this subclass in the development of PBD. Our results, however, indicated that pigeon breeders without symptoms had significantly higher levels of serum IgG4 and that there were no significant differences with regard to the lavage fluid levels of IgG4, IgG3, or total IgG antibody in the two groups of subjects. A tendency of higher IgG4 antibody levels was found in lavage fluid from subjects without symptoms. These results do not support the hypothesis that IgG4 may act as a reaginic trigger in the development of PBD symptoms.

Louis E. Siltzbach Memorial Lecture. Concepts of pathogenesis and lung reactivity in hypersensitivity pneumonitis

It is surprising that forms of hypersensitivity pneumonitis do not occur more frequently, given the variety of biologic dusts and airborne antigens that have been found to cause disease. Exposure is almost universal in some occupations that involve handling animals or feed products, and development of humoral immunity occurs in most; however, overt respiratory illness is relatively infrequent or not easily recognized by the subject. What differs between symptomatic and asymptomatic subjects is not certain, but unique host resistance or susceptibility, as the case may be, appears to be a factor. This may have a genetic basis, but this has not been investigated vigorously. With repeated airborne exposure to appropriate antigens, a humoral and a local respiratory antibody response occur but perhaps with little disease consequence, as most subjects so immunized remain clinically asymptomatic. So far as is known, there is no other route of antigenic exposure except through the respiratory tract, but contact with the antigens could occur on the skin or on mucosal surfaces such as the conjunctiva, or antigens could be ingested by swallowing nasopharyngeal secretions. Except for serum antibodies, however, there is little documentation that other systemic organs are affected, as may occur with sarcoidosis. Of course there is great variability in the age of the subjects and the dosage of antigen to which the subject is exposed, and the frequency and duration of exposure can vary considerably. All of these would seem to be easily tested, however, in an animal model where most of the variables could be independently controlled and varied at will. Even the genetic and aging factors, which are the most difficult parameters to control in humans, could be investigated. Yet, it has been very difficult and perplexing not to have created a more faithful model of hypersensitivity pneumonitis in the laboratory. It is virtually impossible to cause predictable lung disease without the use of an adjuvant that will induce some measure of delayed or cellular hyperreactivity. The acute lung disease caused by antigen-antibody reactions seems too explosive and severe, for its acute disease counterpart of hypersensitivity pneumonitis in humans and the persistence of histologic changes in lung tissue is brief and is usually resolved within 1-2 weeks. A chronic model producing granulomas and fibrosis has been difficult to construct, although the work reported by Fulmer and colleagues is very encouraging.(ABSTRACT TRUNCATED AT 400 WORDS)

'Atypical pneumonia' due to parakeet sensitivity: bird fancier's lung in a 10-year-old girl

p6trinsic allergic alveolitis is rare in childhood, with most of the cases reported due to exposure to avian precipitins (Stiem et al. 1966; Dinda et al. 1969; Chandra & Everly Jones 1972; El-Hefny et al. 1980). We report a 10-year-old girl with bird fancier's lung, and suggest that environmental antigens should be sought in children presenting with non-resolving chest disease.

Canary fancier's lung

A 54-year-old man presented with features consistent with extrinsic allergic alveolitis occurring after contact with his pet birds. Screening of the serum for avian precipitating antibody was negative but canary precipitins were present. Extrinsic allergic alveolitis to his pet canaries was confirmed by inhalation challenge.

Antibodies to hen and duck antigens in poultry workers

Serum antibodies to avian and Aspergillus antigens were detected by enzyme-linked immunosorbent assays (ELISA) in forty-two workers from a poultry abattoir and in twenty healthy blood donors. The levels of IgG and IgA antibodies to hen and duck serum were significantly higher in poultry workers than in blood donors (P less than 0.01). In workers employed for less than 1 year the antibody levels were lower than in those who had been employed for a longer period of time (P less than 0.05). The IgA antibody level to a high molecular weight Aspergillus antigen was higher in poultry workers than blood donors (P less than 0.05), whereas the level of other Aspergillus antibodies were similar in the two groups. The level of IgG antibodies to hen antigen was higher in non-smokers than in smokers (P less than 0.02). A correlation between the antibody levels to hen and duck antigens and to pigeon antigen was found (P less than 0.05), indicating cross-reactivity between these antibodies. No cases of allergic alveolitis were found, and no correlation between antibody levels and respiratory symptoms could be demonstrated.

Extrinsic allergic bronchiolitis in a bird fancier

A patient in whom a severe systemic illness was characterised by weight loss, arthralgia and breathlessness was exposed to her pet bird. This pragmatic approach reproduced the features of her illness. The changes that occurred in her pulmonary physiology and histology differed from those seen in extrinsic allergic alveolitis in many important respects.