Pérez, Evans R. Fernández

Abstract Rationale Dyspnea is a prominent symptom of fibrotic hypersensitivity pneumonitis (fHP), limiting patients’ activity and impairing their quality of life. The University of California San Diego Shortness of Breath questionnaire (UCSD-SOBQ) is a 24-item instrument used to assess dyspnea severity in patients with various respiratory conditions. Objectives This study aimed to examine the reliability and responsiveness of the UCSD-SOBQ score, its validity as a measure of dyspnea severity, and its prognostic value in a prospective cohort with fHP. Methods We conducted psychometric analyses on UCSD-SOBQ response data and assessed the association between score changes and survival in patients with fHP who completed the UCSD-SOBQ and other HP severity metrics at baseline, 6 and 12 months. We introduce the reliable change index (RCI) and the likely change index (LCI) to assess the statistical significance of within-individual change in UCSD scores. Results At baseline, internal consistency was high (Cronbach’s alpha = 0.97). Significant moderately strong correlations were observed between UCSD-SOBQ scores and percent predicted forced vital capacity (FVC%), r = -0.46, percent predicted diffusing capacity of the lung for carbon monoxide (DLCO%), r = -0.32, and Borg dyspnea scores r = 0.56. UCSD-SOBQ scores were significantly different between the lowest and highest strata of FVC% (64.9 ± 18.9 vs. 36.2 ± 22.9), DLCO% and Borg scores. The threshold for worsening within-individual change in the UCSD-SOBQ score at 95% confidence was 12 points. A 1-point higher baseline UCSD-SOBQ score was associated with a 2% increase in the risk of death or transplant (HR 1.02, 95% CI 1.00, 1.04). Conclusions In fHP, the UCSD-SOBQ score is a reliable and valid measure of dyspnea severity, is responsive to change, discriminates patients with differing severities, and is associated with transplant free survival. Additional qualitative data and psychometric analyses could tailor the UCSD-SOBQ to fHP and may further improve its measurement properties.

Abstract Rationale Quantitative CT using multiple instance learning (MIL)-usual interstitial pneumonia (UIP) classifier and data-driven textural analysis (DTA) provides objective and reproducible measurements of disease pattern and extent, respectively. However, the understanding of their individual or combined relationships with outcomes in fibrotic hypersensitivity pneumonitis (fHP) remains limited. Objectives To determine whether visual CT patterns of fHP or UIP, a MIL-UIP classifier, baseline and changes in DTA over 12-months and DTA at 12 months are associated with progression-free survival (PFS) in fHP. Methods The primary cohort included 134 participants with fHP. Associations between CT variables and subsequent lung function change, and PFS were assessed using linear mixed models and Cox hazards models. Results were validated in a combined dataset from three independent populations (N = 216). Results Visual patterns of fHP or UIP were not associated with PFS. A baseline MIL-UIP classification and DTA were significantly associated with 24-month PFS. However, the MIL-UIP did not predict PFS after adjusting for DTA fibrosis extent. Over 12 months, a 1-point increase in DTA across and within patients resulted in a significant decline in FVC% and DLCO%. A 12-month change in DTA (HR = 1.07, 95%CI 1.01-1.13) and DTA at 12-months (HR = 1.03, 95%CI 1.01-1.05) were associated with subsequent 12-month PFS. Similar estimates were observed in the validation cohort. Conclusions In fHP, the objectively measured extent of lung fibrosis is more prognostic than either a UIP classifier or visual CT patterns of fHP or UIP. Baseline DTA, DTA at 12 months, and its change over 12-months are associated with PFS.

Assessment of lung biopsies for the diagnosis of hypersensitivity pneumonitis (HP) is one of the most difficult diagnostic problems for surgical pathologists. It is a form of interstitial lung disease resulting from an immune reaction provoked by an inhaled antigen in susceptible individuals. Although this definition sounds simple, in practice, the diagnosis of HP can be challenging. To address these issues, the American College of Chest Physicians (CHEST) has recently published a guideline for the diagnosis of HP. In this review, we will explore the multidisciplinary diagnostic evaluation of HP with a focus on the pathologic features as outlined in the CHEST guidelines. The histologic criteria are divided into 4 diagnostic categories: (1) Typical nonfibrotic HP or fibrotic HP; (2) Compatible with nonfibrotic HP or fibrotic HP; (3) Indeterminate for nonfibrotic or fibrotic HP; and (4) Alternative Diagnosis. It is important to emphasize that patterns 1 to 3 do not represent discrete histologic entities or pathologic diagnoses. Rather, these categories are meant to serve as a practical guide for organizing a complex set of overlapping histologic patterns into an integrated diagnostic framework for facilitating multidisciplinary discussion. High-resolution computed tomography features are also summarized, emphasizing how the correlation of lung biopsies with computed tomography findings can help to favor the diagnosis, particularly in cases where biopsies are not typical for HP. This review highlights details of the histologic spectrum of HP as well as the utility of different types of biopsies and bronchoalveolar lavage. We also emphasize the importance of multidisciplinary discussion and the complex differential diagnosis.

Abstract Rationale Granulomatous-lymphocytic interstitial lung disease (GLILD) has emerged as a major cause of morbidity in patients with common variable immunodeficiency (CVID). While GLILD is among the most serious noninfectious pulmonary complications of CVID, risk factors for this condition have not been reported. Objectives To identify clinical, physiologic, and serologic risk factors for GLILD in adults with CVID. Methods Of 345 consecutive adult patients with CVID, we identified 34 in the National Jewish Health research database who had a radiographic-pathologic diagnosis of GLILD evaluated between 2002 and 2014. Each case was age and sex matched to 52 CVID control subjects. We used logistic regression to determine independent predictors of GLILD. A mixed effects model was used to estimate the longitudinal change in percent predicted FVC. Measurements and Main Results: The mean time from CVID diagnosis to GLILD detection was 7.8 years. Compared with matched control subjects, cases were more likely to have a history of autoimmune cytopenia, hypersplenism, polyarthritis, lower marginal zone and switched memory B cells, and restrictive lung function. Multivariate analysis revealed that hypersplenism (odds ratio [OR], 24; 95% confidence interval [CI], 4.5–179.1), polyarthritis (OR, 19; 95% CI, 2.3–206.8), and percent predicted FVC (OR, 0.93; 95% CI, 0.87–0.98) were independently associated with the development of GLILD. The rate of change of percent predicted FVC (slope, P = 0.48) did not vary significantly in patients with GLILD over a mean follow-up of 7 years after diagnosis. Conclusions Hypersplenism and polyarthritis are strong risk factors for GLILD in patients with CVID. Percent predicted FVC remained stable over time in patients with GLILD.

Background Acute lung injury (ALI) is a serious postoperative complication with limited treatment options. A preoperative risk-prediction model would assist clinicians and scientists interested in ALI. The objective of this investigation was to develop a surgical lung injury prediction (SLIP) model to predict risk of postoperative ALI based on readily available preoperative risk factors. Methods Secondary analysis of a prospective cohort investigation including adult patients undergoing high-risk surgery. Preoperative risk factors for postoperative ALI were identified and evaluated for inclusion in the SLIP model. Multivariate logistic regression was used to develop the model. Model performance was assessed with the area under the receiver operating characteristic curve and the Hosmer-Lemeshow goodness-of-fit test. Results Out of 4,366 patients, 113 (2.6%) developed early postoperative ALI. Predictors of postoperative ALI in multivariate analysis that were maintained in the final SLIP model included high-risk cardiac, vascular, or thoracic surgery, diabetes mellitus, chronic obstructive pulmonary disease, gastroesophageal reflux disease, and alcohol abuse. The SLIP score distinguished patients who developed early postoperative ALI from those who did not with an area under the receiver operating characteristic curve (95% CI) of 0.82 (0.78-0.86). The model was well calibrated (Hosmer-Lemeshow, P = 0.55). Internal validation using 10-fold cross-validation noted minimal loss of diagnostic accuracy with a mean ± SD area under the receiver operating characteristic curve of 0.79 ± 0.08. Conclusions Using readily available preoperative risk factors, we developed the SLIP scoring system to predict risk of early postoperative ALI.

The practice of platelet transfusion in the intensive care unit varies, and liberal use may not be associated with improved outcome. This study reviewed the medical records of 117 patients with moderate-to-severe thrombocytopenia and without active bleeding who were admitted to intensive care unit beds during a 6-month period. The primary outcome measures were new bleeding episodes and platelet transfusion complications. Ninety (77%) received a platelet transfusion. Significant new bleeding developed in 1 patient who received a transfusion. Six patients (8%) developed transfusion complications: 2 transfusion-related acute lung injury, 2 allergic, and 2 febrile reactions. Patients who did not receive platelet transfusion had a higher severity of illness than transfused patients. Predictors of platelet transfusion were platelet count and postoperative status, but not invasive procedure. The practice of platelet transfusion in critically ill patients with thrombocytopenia varies. Prospective studies evaluating restrictive versus liberal platelet transfusion strategies are warranted.

Background Respiratory failure is a leading cause of postoperative morbidity and mortality in patients undergoing pneumonectomy. The authors hypothesized that intraoperative mechanical ventilation with large tidal volumes (VTs) would be associated with increased risk of postpneumonectomy respiratory failure. Methods Patients undergoing elective pneumonectomy at the authors' institution from January 1999 to January 2003 were studied. The authors collected data on demographics, relevant comorbidities, neoadjuvant therapy, pulmonary function tests, site and type of operation, duration of surgery, intraoperative ventilator settings, and intraoperative fluid administration. The primary outcome measure was postoperative respiratory failure, defined as the need for continuation of mechanical ventilation for greater than 48 h postoperatively or the need for reinstitution of mechanical ventilation after extubation. Results Of 170 pneumonectomy patients who met inclusion criteria, 30 (18%) developed postoperative respiratory failure. Causes of postoperative respiratory failure were acute lung injury in 50% (n = 15), cardiogenic pulmonary edema in 17% (n = 5), pneumonia in 23% (n = 7), bronchopleural fistula in 7% (n = 2), and pulmonary thromboembolism in 3% (n = 1). Patients who developed respiratory failure were ventilated with larger intraoperative VT than those who did not (median, 8.3 vs. 6.7 ml/kg predicted body weight; P < 0.001). In a multivariate regression analysis, larger intraoperative VT (odds ratio, 1.56 for each ml/kg increase; 95% confidence interval, 1.12-2.23) was associated with development of postoperative respiratory failure. The interaction between larger VT and fluid administration was also statistically significant (odds ratio, 1.36; 95% confidence interval, 1.05-1.97). Conclusion Mechanical ventilation with large intraoperative VT is associated with increased risk of postpneumonectomy respiratory failure.