Citations

Abstract Psychological stress can lead to asthma exacerbations in some patients. It is our hypothesis that the stress effect can occur through an enhancement of allergic inflammatory response. To investigate this possibility, airway antigen challenge was evaluated in 20 college students with mild asthma during both a low-stress phase (midsemester or two weeks postfinal examination) and a stress phase (final examination week). Subjects completed questionnaires to assess psychological state and underwent inhaled antigen challenge. Sputum samples were collected before challenge, and six and 24 hours and seven days postchallenge. Leukocytes were counted and eosinophil-derived neurotoxin (EDN) was measured in sputum supernates. Sputum cells were cultured and stimulated ex vivo with phytohemagglutinin (10 μ g/ml), and culture supernates were assayed for interleukin-5 (IL-5) and interferon- γ by enzyme-linked immunosorbent assay. Sputum eosinophils and EDN levels significantly increased at six and 24 hours postchallenge and were enhanced during the stress phase (p < 0.01). IL-5 generation by sputum cells was also increased at 24 hours during stress and correlated with airway eosinophils (rs = 0.65, p < 0.05). Students' anxiety and depression scores were significantly higher during the examination period. Our findings suggest that stress associated with final examinations can act as a cofactor to increase eosinophilic airway inflammation to antigen challenge and thus may enhance asthma severity.

Abstract Studies suggest that screening with spiral computed tomography can detect lung cancers at a smaller size and earlier stage than chest radiography can. To evaluate low-radiation-dose spiral computed tomography and sputum cytology in screening for lung cancer, we enrolled 1,520 individuals aged 50 yr or older who had smoked 20 pack-years or more in a prospective cohort study. One year after baseline scanning, 2,244 uncalcified lung nodules were identified in 1,000 participants (66%). Twenty-five cases of lung cancer were diagnosed (22 prevalence, 3 incidence). Computed tomography alone detected 23 cases; sputum cytology alone detected 2 cases. Cell types were: squamous cell, 6; adenocarcinoma or bronchioalveolar, 15; large cell, 1; small cell, 3. Twenty-two patients underwent curative surgical resection. Seven benign nodules were resected. The mean size of the non-small cell cancers detected by computed tomography was 17 mm (median, 13 mm). The postsurgical stage was IA, 13; IB, 1; IIA, 5; IIB, 1; IIIA, 2; limited, 3. Twelve (57%) of the 21 non-small cell cancers detected by computed tomography were stage IA at diagnosis. Computed tomography can detect early-stage lung cancers. The rate of benign nodule detection is high.

Abstract Findings of surgical lung biopsy (SLB) are important in categorizing patients with idiopathic interstitial pneumonia (IIP). We investigated whether histologic variability would be evident in SLB specimens from multiple lobes in patients with IIP. SLBs from 168 patients, 109 of whom had multiple lobes biopsied, were reviewed by three pathologists. A diagnosis was assigned to each lobe. A different diagnosis was found between lobes in 26% of the patients. Patients with usual interstitial pneumonia (UIP) in all lobes were categorized as concordant for UIP (n = 51) and those with UIP in at least one lobe were categorized as discordant for UIP (n = 28). Patients with nonspecific interstitial pneumonia (NSIP) in all lobes were categorized as having fibrotic (n = 25) or cellular NSIP (n = 5). No consistent distribution of lobar histology was noted. Patients concordant for UIP were older (63 ± 9 [mean ± SD] yr; p < 0.05 as compared with all other groups) than those discordant for UIP (57 ± 12 yr) or with fibrotic NSIP (56 ± 11 yr) or cellular NSIP (50 ± 9 yr). Semiquantitative high-resolution computed tomography demonstrated a varied profusion of fibrosis (p < 0.05 for all group comparisons), with more fibrosis in concordant UIP (2.13 ± 0.62) than in discordant UIP (1.42 ± 0.73), fibrotic NSIP (0.83 ± 0.58), or cellular NSIP (0.44 ± 0.42). Survival was better for patients with NSIP than for those in both UIP groups (p < 0.001), although survival in the two UIP groups was comparable (p = 0.16). Lobar histologic variability is frequent in patients with IIP, patients with a histologic pattern of UIP in any lobe should be classified as having UIP.

Abstract Noninvasive positive pressure ventilation (NPPV) is usually applied using pressure support ventilation (PSV). Proportional assist ventilation (PAV) is a newer mode that delivers assisted ventilation in proportion to patient effort. We hypothesized that PAV for NPPV would support gas exchange and avoid intubation as well as PSV and be more comfortable and tolerable for patients. Adult patients with acute respiratory insufficiency were randomized to receive NPPV with PAV delivered using the Respironics Vision ventilator or PSV using a Puritan-Bennett 7200ae critical care ventilator. Each mode was adjusted to relieve dyspnea and improve gas exchange until patients met weaning or intubation criteria, died, or refused to continue. Twenty-one and 23 patients were entered into the PAV and PSV groups, respectively, and had similar diagnoses and baseline characteristics, although pH was slightly lower in the PAV group (7.30 versus 7.35, p = 0.02). Mortality and intubation rates were similar, but refusal rate was lower, reduction in respiratory rate was more rapid, and there were fewer complications in the PAV group. We conclude that use of the PAV mode is feasible for noninvasive therapy of acute respiratory insufficiency. Compared with PSV delivered with the Puritan-Bennett 7200ae, PAV is associated with more rapid improvements in some physiologic variables and is better tolerated.

Abstract We report findings in 70 patients with both diffuse interstitial lung disease and either polymyositis (PM) or dermatomyositis (DM). Initial presentations were most commonly either musculoskeletal (arthralgias, myalgias, and weakness) or pulmonary (cough, dyspnea, and fever) symptoms alone; in only 15 patients (21.4%) did both occur simultaneously. Pulmonary disease usually took the form of acute to subacute antibiotic-resistant community-acquired pneumonia. Chest radiographs and computed tomography most commonly demonstrated bilateral irregular linear opacities involving the lung bases; occasionally consolidation was present. Jo-1 antibody was present in 19 (38%) of 50 patients tested. Synchronous associated malignancy was present in 4 of 70 patients (5.7%). Surgical lung biopsies disclosed nonspecific interstitial pneumonia (NSIP) in 18 of 22 patients (81.8%), organizing diffuse alveolar damage (DAD) in 2, bronchiolitis obliterans organizing pneumonia (BOOP) in 1, and usual interstitial pneumonia (UIP) in 1. Treatment usually included prednisone in 40–60 mg/d dosages for initial control, followed by lower dose prednisone plus an immunosuppressive agent such as azathioprine or methotrexate for disease suppression. Survival was significantly better than that observed for historical control subjects with idiopathic UIP, and was more consistent with survival previously reported in idiopathic NSIP. There was no difference in survival between Jo-1 positive and Jo-1 negative groups.

Abstract It is hypothesized that the extent and severity of fibrosis and cellularity found on lung biopsy determine the prognosis and response to therapy in idiopathic pulmonary fibrosis (IPF). The objective of this study was to determine which histopathologic features predict survival in IPF. We prospectively studied 87 patients with usual interstitial pneumonia (UIP) confirmed by surgical lung biopsy. Four pathologists independently graded the extent and severity of specific histopathologic features. We used Cox proportional-hazards models to assess the effect of histopathologic patterns on patients' survival. The effects of age, sex, and smoking were also included in the analysis. Sixty-three patients died during the 17-yr study period. Survival was longer in subjects with lesser degrees of granulation/connective tissue deposition (fibroblastic foci). The degree of alveolar space cellularity, alveolar wall fibrosis, and cellularity did not affect survival. A history of cigarette smoking, the level of dyspnea, and the degree of lung stiffness at presentation were also shown to be independent factors predicting survival. The extent of fibroblastic foci present on lung biopsy predicts survival in IPF. These findings support the hypothesis that the critical pathway to end-stage fibrosis is not “alveolitis” but rather the ongoing epithelial damage and repair process associated with persistent fibroblastic proliferation. Controlling these processes, rather than stopping inflammation, appears most important in preventing progressive disease and the fatal outcome common in IPF.

Abstract Lymphangioleiomyomatosis (LAM) and multifocal micronodular pneumocyte hyperplasia (MMPH) produce cystic and nodular disease, respectively, in the lungs of patients with tuberous sclerosis. The objective of this study was to prospectively characterize the prevalence, clinical presentation, and genetic basis of lung disease in TSC. We performed genotyping and computerized tomographic (CT) scanning of the chest on 23 asymptomatic women with tuberous sclerosis complex (TSC). Cystic pulmonary parenchymal changes consistent with LAM were found in nine patients (39%). These patients tended to be older than cyst-negative patients (31.9 ± 7.6 yr versus 24.8 ± 11.6 yr, p = 0.09). There was no correlation between presence of cysts and tobacco use, age at menarche, history of pregnancy, or estrogen-containing medications. Three of the cyst-positive patients had a prior history of pneumothorax. Pulmonary function studies revealed evidence of gas trapping but normal spirometric indices in the cyst-positive group. All nine cyst-positive patients had angiomyolipomas (AML), which were larger (p < 0.05) and more frequently required intervention (p = 0.08) than cyst-negative patients (8 of 14 with AMLs, p < 0.05). Ten patients (43%) had pulmonary parenchymal nodules. Pulmonary nodules were more common in women with cysts (78% versus 21%, p < 0.05), and 52% of all patients had either cystic or nodular changes. TSC2 mutations were identified in all cyst-positive patients who were tested (n = 8), whereas both TSC1 and TSC2 mutations were found in patients with nodular disease. Correlation of the mutational and radiographic data revealed one pair of sisters who were discordant for cystic disease, two mother– daughter pairs who were discordant for nodular disease, and no clear association between cyst development and a specific mutational type. This prospective analysis demonstrates that cystic and nodular pulmonary changes consistent with LAM and MMPH are common in women with TSC.