Novel acute hypersensitivity pneumonitis model induced by airway mycosis and high dose lipopolysaccharide

BACKGROUND

Inhalation of fungal spores is a strong risk factor for severe asthma and experimentally leads to development of airway mycosis and asthma-like disease in mice. However, in addition to fungal spores, humans are simultaneously exposed to other inflammatory agents such as lipopolysaccharide (LPS), with uncertain relevance to disease expression. To determine how high dose inhalation of LPS influences the expression of allergic airway disease induced by the allergenic mold Aspergillus niger (A. niger).

METHODS

C57BL/6J mice were intranasally challenged with the viable spores of A. niger with and without 1 μg of LPS over two weeks. Changes in airway hyperreactivity, airway and lung inflammatory cell recruitment, antigen-specific immunoglobulins, and histopathology were determined.

RESULTS

In comparison to mice challenged only with A. niger, addition of LPS (1 μg) to A. niger abrogated airway hyperresponsiveness and strongly attenuated airway eosinophilia, PAS+ goblet cells and TH2 responses while enhancing TH1 and TH17 cell recruitment to lung. Addition of LPS resulted in more severe, diffuse lung inflammation with scattered, loosely-formed parenchymal granulomas, but failed to alter fungus-induced IgE and IgG antibodies.

CONCLUSIONS

In contrast to the strongly allergic lung phenotype induced by fungal spores alone, addition of a relatively high dose of LPS abrogates asthma-like features, replacing them with a phenotype more consistent with acute hypersensitivity pneumonitis (HP). These findings extend the already established link between airway mycosis and asthma to HP and describe a robust model for further dissecting the pathophysiology of HP.

Chronic Pulmonary Aspergillosis with Pleuroparenchymal Fibroelastosis-like Features

A 64-year-old man who presented with repeated bouts of pneumothorax was admitted to our hospital because of gradually progressive dyspnea and repeated episodes of a fever. The physiological, radiological and pathological findings were consistent with pleuroparenchymal fibroelastosis (PPFE). In addition, the serum-specific precipitating antibody for Aspergillus was positive. After the administration of voriconazole, a marked improvement was observed in the imaging and physiological findings. Given this clinical course, we diagnosed the patient with PPFE secondary to aspergillosis. The present case suggests that a therapeutic approach based on the cause of secondary PPFE may improve the prognosis of PPFE.

Clinical features and diagnosis of chronic pulmonary aspergillosis in Chinese patients

Chronic pulmonary aspergillosis (CPA) has recently been recognized as a significant global health burden. In China, the diagnosis of CPA is still unfamiliar to most doctors. The aim of this study was to demonstrate the clinical manifestations and diagnoses of CPA in China.A multidisciplinary team of doctors retrospectively screened 690 records of patients diagnosed with pulmonary aspergillosis from January 2000 to December 2016 at Peking Union Medical College Hospital, Beijing, China. Of these, 69 patients were diagnosed with CPA. The patients' clinical characteristics were then retrieved and analyzed. Demographic, laboratory, and radiological data for these patients were compared by CPA type.Of the 69 patients diagnosed with CPA, 10 patients were diagnosed with chronic cavitary pulmonary aspergillosis (CCPA), 15 patients with semi-invasive aspergillosis (SAIA), 41 patients with simple aspergilloma, and 3 patients with Aspergillus nodule. Further, 53.3% of the SAIA patients were obviously immunocompromised, and 60% of the CCPA patients, 26.7% of the SAIA patients, 7.3% of the simple aspergilloma cases were mildly immunocompromised. Previous underlying lung abnormalities were observed in 20% of CCPA patients, 53.3% of SAIA patients, and 80.5% of simple aspergilloma patients. The most common symptoms in the CPA patients were cough (92.8%), hemoptysis (63.8%), chronic sputum (23.2%), and fever (17.4%). The most common computerized tomography abnormalities were cavities (94.2%), nodule (84.1%), consolidation (4.3%), pleural thickening (2.9%), and infiltration (2.9%). CCPA, SAIA and simple aspergilloma patients were significantly different with respect to their course before diagnosis, constitutional symptoms, fever, hemoptysis, breathlessness, white blood cell count, erythrocyte sedimentation rate, high-sensitivity C-reactive protein count, presence of nodule, and presence of a solitary lesion (all P < .05). Furthermore, SAIA patients had a significantly shorter course before diagnosis and a significantly higher white blood cell count compared with CCPA patients (both P < .01).In China, underlying systemic immunocompromising conditions and lung diseases with mechanical impediments contribute to CPA. Simple aspergillosis was the most common diagnosis in CPA patients. The imaging characteristics of simple aspergillosis and Aspergillus nodules were quite discriminable, while CCPA, and SAIA were similar in their clinical and radiological features. Distinguishing between CCPA and SAIA depends mainly on the physician's clinical judgment.

Microbial colonization and lung function in adolescents with cystic fibrosis

With intensified antibiotic therapy and longer survival, patients with cystic fibrosis (CF) are colonized with a more complex pattern of bacteria and fungi. However, the clinical relevance of these emerging pathogens for lung function remains poorly defined. The aim of this study was to assess the association of bacterial and fungal colonization patterns with lung function in adolescent patients with CF. Microbial colonization patterns and lung function parameters were assessed in 770 adolescent European (German/Austrian) CF patients in a retrospective study (median follow-up time: 10years). Colonization with Pseudomonas aeruginosa and MRSA were most strongly associated with loss of lung function, while mainly colonization with Haemophilus influenzae was associated with preserved lung function. Aspergillus fumigatus was the only species that was associated with an increased risk for infection with P. aeruginosa. Microbial interaction analysis revealed three distinct microbial clusters within the longitudinal course of CF lung disease. Collectively, this study identified potentially protective and harmful microbial colonization patterns in adolescent CF patients. Further studies in different patient cohorts are required to evaluate these microbial patterns and to assess their clinical relevance.

Surgical management of pulmonary aspergilloma: clinical experience with 77 cases

BACKGROUND/AIM

This retrospective study evaluated the clinical presentation, underlying lung disease, surgical indications, technique, treatment outcomes, and postoperative complications of pulmonary aspergilloma.

MATERIALS AND METHODS

We evaluated 77 patients who underwent pulmonary resection of an aspergilloma at Atatürk Chest Diseases and Thoracic Surgery Research and Training Hospital between January 2000 and December 2013. The initial operations were 4 pneumonectomies, 24 lobectomies, 9 lobectomy plus myoplasties, 10 segmental resections, and 30 wedge resections. Six reoperations were carried out to deal with postoperative complications: 1 myoplasty, 2 completion lobectomies plus myoplasties, 2 myoplasties with rib resections, and 1 completion lobectomy.

RESULTS

The subjects comprised 53 males (mean age: 44.26 (range: 10-73) years) and 24 females (mean age: 48.25 (range: 26-70) years). The most common indication for surgery was hemoptysis in 52 patients (67.53%). The most common underlying lung disease was tuberculosis in 37 patients (48.05%). Forty patients (51.94%) had a simple pulmonary aspergilloma and 37 (48.05%) had a complex pulmonary aspergilloma. Major complications occurred in 18 patients (23.37%). The postoperative mortality rate was 3.89%, with 3 patients dying.

CONCLUSION

Surgical resection of pulmonary aspergilloma is the best way to prevent recurrent hemoptysis with low morbidity and mortality.

Hypothermic endpoint for an intranasal invasive pulmonary aspergillosis mouse model

Immunocompromised mice were infected intranasally with Aspergillus fumigatus as part of a vaccine efficacy study. Although body temperature was measured throughout the study, a formal evaluation of its usefulness as an endpoint criterion was not performed. We retrospectively evaluated survival data and temperature records to determine whether body temperature can be used as an objective predictor of death and included in the humane endpoint criteria for this mouse model. CF1 mice were immunosuppressed with either cortisone acetate or by treatment with antiGR1 (a neutrophil-depleting antibody) and then intranasally challenged with A. fumigatus. Body temperature was measured by using an infrared noncontact thermometer a maximum of 3 times daily until death or euthanasia. A surface body temperature below 29.0 °C was correlated with a poor chance of survival, and using this cutoff point with signs of morbidity (hunched, ruffled fur, respiratory distress) reliably indicates mice for euthanasia without negatively affecting data collection. Using 2 subsequent readings of less than 31.0 °C as an endpoint would have led to premature euthanasia of only one mouse (2.2%). As a single reading, a body temperature of 28.8 °C had a sensitivity of 92.2% and specificity of 90.9%. Hypothermia proved to be a useful addition to the humane endpoint criteria for this mouse model, and veterinary and research groups should discuss their study needs in relation to animal welfare to best determine the most appropriate means of including this parameter.