A Comparison of Global Lung Initiative 2012 with Third National Health and Nutrition Examination Survey Spirometry Reference Values. Implications in Defining Obstruction.

RATIONALE: Obstructive lung disease is diagnosed by a decreased ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC); however, there is no universally accepted lower limit of normal for the FEV1/FVC ratio. Current established reference values use the Third National Health and Nutrition Examination Survey (NHANES III) database. In 2012, the Global Lung Initiative (GLI) introduced GLI12, which is a compilation reference set that uses standard deviation values to define normal spirometry. OBJECTIVES: To evaluate the changes in classification of obstructive spirometry with use of GLI12 compared with NHANES III in a heterogeneous, multiracial population. METHODS: We evaluated the spirometry studies conducted in our pulmonary function laboratory between January 2005 and December 2015. NHANES III reference equations were calculated to predict lower limits of normal for FEV1, FVC, and FEV1/FVC. GLI12 values were established using European Respiratory Society published computer software. FEV1 severity was graded using 2005 American Thoracic Society guidelines for NHANES III and using z-score-based criteria for GLI12. Asymmetric partition analysis evaluated agreement between the reference sets. RESULTS: A total of 11,888 studies were evaluated. Obstruction was diagnosed in 2,857 studies using NHANES III versus 2,489 studies using GLI12. Agreement regarding the presence or absence of obstruction occurred in 2,483 of studies with obstruction and 9,025 studies without obstruction (agreement, 96.8%; κ = 0.91). Of the studies with obstruction, 1,595 had agreement in severity grading. Overall, agreement regarding obstruction and severity grading occurred in 10,620 studies, representing 89.3% of all studies. A total of 380 studies (3.2%) had discordance regarding the presence or absence of obstruction, 34.0% (844 of the 2,483 obstruction studies) had a one-degree of change in FEV1 disease severity scoring, with 44 cases (1.8%) that had changes of two categories in FEV1 severity scores. No studies had greater than two degrees of change. Asymmetric partition analysis suggested that the highest clinically significant changes were seen in older individuals, particularly African American men older than 65. CONCLUSIONS: Our evaluation suggests that there is moderate overall agreement between NHANES III and GLI12. We found a 3.2% change in classification of obstruction when transitioning from NHANES III to GLI12. When incorporating a z-score-based FEV1 and GLI12 reference set, 10.7% of the spirometry studies had a change in their categorization. The disagreement between the two datasets was most pronounced in elderly subjects. Although we cannot endorse one reference set over the other, we highlight the potential implications of adopting the GLI12 reference sets and suggest caution when interpreting spirometry in the elderly.

Acute eosinophilic pneumonia in the deployed military setting.

RATIONALE: Acute eosinophilic pneumonia (AEP) is a rare but important cause of severe respiratory failure most typically caused by cigarette smoking, but can also be caused by medications, illicit drugs, infections and environmental exposures. There is growing evidence that disease severity varies and not all patients require mechanical ventilation or even supplemental oxygen. OBJECTIVES: To compare patients with AEP treated at Landstuhl Regional Medical Center (LRMC) to those in other published series, and to provide recommendations regarding diagnosis and treatment of AEP. METHODS: A retrospective chart review was completed on forty-three cases of AEP which were identified from March 2003 through March 2010 at LRMC, Germany. RESULTS: Tobacco smoking was reported by 91% of our patients. Only 33% of patients in our series had a fever (temperature > 100.4 °F) at presentation. Peripheral eosinophilia (>5%) was present in 35% on initial CBC, but was seen in 72% of patients during their hospital course. Hypoxemia, as measured by PaO2/FiO2 ratio, seemed to be less severe in patients with higher levels of bronchoalveolar (BAL) eosinophilia percentage. CONCLUSIONS: Based on our experience and literature review, we recommend adjustments to the diagnostic criteria which may increase consideration of this etiology for acute respiratory illnesses as well as provide clinical clues we have found particularly helpful. Similar to recent reports of initial peripheral eosinophilia correlating with less severe presentation we found that higher BAL eosinophilia correlated with less severe hypoxemia.

Diffuse bronchiectasis as the primary manifestation of endobronchial sarcoidosis.

Sarcoidosis is an idiopathic disease that most commonly involves the lungs and is characterized by granulomatous inflammation. Bronchiectasis is one pulmonary manifestation of sarcoidosis, although it is almost always observed as traction bronchiectasis in the setting of fibrotic lung disease. A 50-year-old woman was evaluated for chronic cough and bronchiectasis with a small amount of peripheral upper lobe honeycombing and no significant pulmonary fibrosis or lymphadenopathy. After an extensive laboratory and imaging evaluation did not identify a cause of her bronchiectasis, bronchoscopy was performed to assess for primary ciliary dyskinesia and revealed a diffuse cobblestone appearance of the airway mucosa. Endobronchial biopsies and lymphocyte subset analysis of bronchoalveolar lavage fluid were consistent with a diagnosis of sarcoidosis. We believe endobronchial sarcoidosis should be included in the differential diagnosis of patients presenting with bronchiectasis.