Pulmonary mycobacterial spindle cell pseudotumor in a lung transplant patient: progression without therapy and response to therapy.

Mycobacterial spindle cell pseudotumor (MSP) represents a rare, non-malignant, mass-forming reaction to various mycobacterial infections, typically occurring in immunocompromised patients. It is characterized by the proliferation of spindle-shaped fibrohistiocytic cells without the formation of epithelioid granulomas. Without staining for acid-fast bacilli, histological distinction from other spindle cell lesions, including malignancy, can be difficult. Most of the MSP cases reported in the literature have involved lymph nodes, skin, spleen, or bone marrow, but rarely involve the lung. MSP predominately occurs in patients who are immunosuppressed. We present a patient with MSP of the transplanted lung caused by non-tuberculous mycobacteria, in whom both the natural course of the untreated pseudotumor as well as the response to antimycobacterial treatments were observed.

The energetic consequences of dietary specialization in populations of the garter snake, Thamnophis elegans.

We investigated the intraspecific variation in digestive energetics between dietary specialist and generalist populations of the Western Terrestrial garter snake (Thamnophis elegans) in northern California. Coastal populations have a specialized diet of slugs and inland populations have a generalized diet of fish, anurans, mice and leeches. The difference in prey preference between the two populations is congenital, heritable and ontogenetically stable. To examine energetic specializations and trade-offs in these populations, we measured the net assimilation efficiency of each snake population on both slug (Ariolimax columbianus) and fish (Rhinichthys osculus) diets. The net assimilation efficiency was measured during digestion of a meal and continued until metabolic rate re-attained prefeeding levels. Coastal snakes were able to utilize 62% more of the ingested energy towards production from slug diets through both increased assimilation of nutrients and reduced digestive costs. For fish, assimilation and digestive costs were the same in both coastal and inland populations. These results support the hypothesis that snakes with specialized diets can evolve physiological traits to extract nutrients more efficiently. However, there was no apparent trade-off on the more generalized diet that was associated with this specialization.

Assessment of a bronchoscopy simulator.

The study objective was to validate a flexible bronchoscopy simulator by determining if it could differentiate between expert and novice bronchoscopists. A subsequent evaluation phase was then done to determine whether use of the simulator would improve the rate of bronchoscopy skill acquisition for new pulmonary fellows. A multicenter prospective cohort study was performed using a bronchoscopy simulator. Three cohorts were evaluated based on the number of bronchoscopies previously performed: "experts" (> 500, n = 9), "intermediates" (25 to 500, n = 8), and "novices" (none, n = 11). Each participant performed two simulated cases with performance measures being recorded by the simulator. Performance measures that distinguished between groups were then used to evaluate the learning curve for new fellows training on the simulator. A randomized-controlled trial was then conducted comparing the quality of bronchoscopy performance for new pulmonary fellows who were trained either with conventional methods or with the simulator. Expert bronchoscopists performed better on the simulator than intermediates who performed better than novices in terms of procedure time, percentage of segments visualized, time in red-out, and wall collisions. Training of new fellows demonstrated that after performing 20 bronchoscopic simulations, the skill level acquired with the simulator significantly improved in terms of speed, percentage of segments visualized, time in red-out, and collisions. Fellows trained on the simulator performed better than fellows trained using conventional methods during their first actual bronchoscopies as assessed by procedure time (815 versus 1,168 s, p = 0.001), a bronchoscopy nurse's subjective quality assessment score (7.7 +/- 0.3 versus 3.7 +/- 2.5, p = 0.05), and by a quantitative bronchoscopy quality score (percentage of segments correctly identified/procedure time, 0.119 +/- 0.015 versus 0.046 +/- 034, p = 0.03). In conclusion, the bronchoscopy simulator was able to accurately assess bronchoscopy experience level. Training new fellows on the bronchoscopy simulator leads to more rapid acquisition of bronchoscopy expertise compared with conventional training methods. This technology has the potential to facilitate bronchoscopy training and to improve objective evaluations of bronchoscopy skills.

Pulmonary T cell repertoire in patients with graft-versus-host disease following blood and marrow transplantation.

Pulmonary inflammation is one of the risk factors associated with blood and marrow transplantation (BMT). To determine the potential role of T cells in pulmonary complications after transplantation, we analyzed the T-cell repertoire expressed in bronchoalveolar lavage fluids from eleven patients with graft-versus-host disease following BMT. A reverse transcriptase-polymerase chain reaction was used to amplify rearranged TCR transcripts in unfractionated, CD4+, and CD8+ T cells from bronchoalveolar lavage fluids. The relative expression of TCR variable (V) gene families and the diversity of junctional region lengths associated with different AV and BV gene families were analyzed. Nearly all TCR AV and BV gene families were detected in bronchoalveolar lavage cells from BMT recipients. Oligoclonal patterns of TCR junctional region lengths were observed in unfractionated, CD4+, and CD8+ bronchoalveolar T cells. The oligoclonal expansion of bronchoalveolar T cells in patients was confirmed by DNA sequencing. TCRV gene expression is almost completely restored in the lungs of BMT recipients as early as two weeks after transplantation. Increased oligoclonality among TCR gene families suggests either an incomplete restoration of TCR diversity or an antigen-driven expansion of T cells in the lungs of BMT recipients with graft-versus-host disease, not necessarily related to pulmonary infection.

Transbronchial needle aspiration: guidance with CT fluoroscopy.

BACKGROUND: Bronchoscopy with transbronchial needle aspiration (TBNA) is valuable to diagnose lesions in the mediastinum and lung, but conventional fluoroscopic guidance may be suboptimal. We describe the use of CT fluoroscopy to provide real-time, transaxial TBNA localization, thus facilitating biopsy. METHODS: Patients were selected because of prior unsuccessful bronchoscopy or anticipated difficulty owing to small size or inaccessibility of the lesion. CT fluoroscopy consists of a spiral CT scanner adapted using a rapid-reconstruction algorithm and hardware that permits real-time in-room imaging. The bronchoscope was inserted on the CT scanner, which was used to guide TBNA instruments into the target lesion. RESULTS: Of 27 patients who underwent TBNA with CT fluoroscopic assistance, 15 had mediastinal nodes, and 12 had lung nodules or focal infiltrates. Mean lesion size was 1.7 cm in the mediastinum, 2. 2 cm in the lung. A correct diagnosis was established in 10 of 12 mediastinal lesions (83%) for which follow-up was available and in 8 lung lesions (67%). Diagnoses included small cell and non-small cell lung cancer and invasive aspergillosis. False-negative results were caused by sampling errors or inability to reach the lesion as documented by CT fluoroscopy. Postprocedure CT fluoroscopy revealed no complications. CONCLUSION: CT fluoroscopy provides effective, real-time guidance for TBNA and may be particularly valuable in patients with small or less accessible mediastinal or lung lesions.

Bronchoscopy training: current fellows' experiences and some concerns for the future.

OBJECTIVES: To determine current pulmonary fellows' perspectives about their bronchoscopy training. DESIGN: Survey of 59 pulmonary fellows selected by training program directors to represent their institutions. SETTING: "Hands-on" symposium at the CHEST 1998 annual meeting, Toronto, Canada. RESULTS: Fellows reported a mean (+/- SD) of 2.4+/- 0.7 years of training, estimated they had performed 77.7+/-34 bronchoscopies per year, and had generally high estimates of their bronchoscopy proficiency and training. Proficiency estimates correlated with number of procedures cited (r = 0.43, p = 0.001) or level of fellowship training (r = 0.40, p = 0.002). Proficiency ratings (r = 0.63, p = 0.0001) and procedure numbers (r = 0.45, p-0. 0004) correlated with program quality ratings. Approaches to bronchoscopy instruction varied, and most often consisted of one-to-one instruction by faculty (92.5%), lecture-based instruction (74.6%), and case discussions (72.9%). Use of bronchoscopy lectures (p = 0.008) or videos (p = 0.057) were associated with higher self-estimates of proficiency, whereas use of lectures (p = 0.002), a bronchoscopy text (p = 0.009), and one-on-one instruction (p = 0.05) were associated with more highly ranked programs. Major components of training varied among programs. Although most fellows had received instruction encompassed in basic bronchoscopy, fewer had experience with bronchoscopic intubation (71.2%), transbronchial needle aspiration (72.9%), quantitative bacterial culture (64.4%), stent placement (27.1%), laser photocoagulation (25.4%), or cryotherapy (6.8%). Components of bronchoscopy experiences correlated with fellows' estimates of bronchoscopy proficiency and program quality. CONCLUSIONS: Approaches to bronchoscopy instruction and the components of bronchoscopy experiences vary considerably among institutions and are associated with pulmonary fellows' perceptions of bronchoscopy proficiency and training program quality. Definition of an optimum bronchoscopy curriculum remains necessary.

Diffuse alveolar damage. Morphologic features in bronchoalveolar lavage fluid.

OBJECTIVE: To evaluate the overall cytologic characteristics of diffuse alveolar damage (DAD) in bronchoalveolar lavage (BAL) specimens in search of features that could be useful in cytologic diagnosis. STUDY DESIGN: We evaluated BAL samples from patients with DAD obtained simultaneously with transbronchial biopsies (n = 8) or open lung biopsies (n = 2) or within 24 hours of autopsy (n = 2). The material was processed routinely for cytologic and histologic evaluation. RESULTS: The smears were moderately to highly cellular. All cases had large numbers of alveolar macrophages and/or desquamated alveolar cells. The epithelial component displayed various degrees of nuclear atypia. Some epithelial clusters were three-dimensional, with peripheral cells showing clear cytoplasm, protruding outwards and resembling hobnails. Other aggregates appeared two-dimensional, as sheets of cells with flattened and dense cytoplasm (squamotized). Both types of cell clusters were often associated with dense, basophilic or amphophilic, amorphous extracellular material. Counterparts of all the cytologic features were observed in the histologic material, including atypia of the alveolar lining with hobnailing, squamotization, amorphous extracellular material and hyaline membranes. CONCLUSION: The cytologic features of BAL represent a constellation of alveolar cell injury. Based on these features, DAD can be correctly diagnosed or suggested in BAL samples in the appropriate clinical setting.

The noninfectious respiratory complications of infection with HIV.

Infection with HIV was first recognized through a clustering of unusual respiratory infections. The lung has been a major target manifesting many of the infectious complications of the immunodeficiency. Noninfectious pulmonary complications in HIV-infected individuals are also common and have been recognized since the advent of the AIDS epidemic. Malignancies involving the respiratory system, specifically Kaposi's sarcoma and non-Hodgkin's lymphoma, are epidemiologically linked to infection with HIV. Although other cancers have been identified in patients with HIV, these malignancies have a relationship to HIV infection that is unknown. Nonetheless, all cancers in the HIV-infected individual appear to follow a very deadly course. Interstitial pneumonitis and an alveolitis are also seen in individuals infected with HIV. Their relationship to the virus is unknown but may involve the lung's immune response to HIV. Pneumothorax and bullous lung disease are the sequela of pulmonary infections in the HIV-infected host. Pulmonary hypertension has been reported in HIV-infected patients, and like the other noninfectious respiratory complications, the link between the disease process and HIV is unknown. Bronchiectasis is now commonly recognized in AIDS patients who have survived prolonged immunosuppression and infection. Bronchoscopists have accumulated a collection of endobronchial lesions uncommonly seen in non-HIV-related pulmonary consultation. In the following review, we discuss the epidemiology, pathology, pathogenesis, clinical features, diagnostic findings, prognosis, and therapeutic options available for each noninfectious pulmonary complication. As the life expectancy for HIV-infected patients increases, the incidence of noninfectious pulmonary complications will rise.

High attenuation mucous plugs in allergic bronchopulmonary aspergillosis: CT appearance.

Allergic bronchopulmonary aspergillosis is an immunologic disease characterized by bronchiectasis and recurrent mucous plugging in asthmatics. The usual CT appearance is that of low attenuation branching structures corresponding to impacted dilated bronchi. We report a patient with allergic bronchopulmonary aspergillosis and mucous plugging manifested by high attenuation structures on CT. A follow-up examination demonstrated resolution of the mucous secretions and residual bronchiectasis. Possible etiologies for this CT appearance are discussed.

Needle brush in the diagnosis of lung mass or nodule through flexible bronchoscopy.

Transbronchial needle aspiration (TBNA), in comparison with cytology brush and forceps biopsy, in the diagnosis of a pulmonary mass or coin lesions has been studied by Shure and Wang in the past. Both studies concluded that TBNA markedly increased the diagnostic yield. A new instrument, a "needle brush" (Mill Rose Lab), has been developed and compared with the following three instruments: a regular cytology brush was used first, followed by needle brush, TBNA, and forceps biopsy under fluoroscopy. Twenty-four patients were studied. A specific diagnosis was made in 16 patients (15 malignancies; one granuloma); in three patients, results were suspicious for malignancy, three patients had negative results, and in two patients the study was not complete. "Needle brush" biopsy was positive in 11 patients (exclusively in four); TBNA was positive in eight (exclusively in two). Regular brush biopsy was positive in seven (exclusively in none). Forceps biopsy was positive in four (exclusively in one; granuloma). We conclude that the needle brush and TBNA have a higher diagnostic yield in malignant lung masses or nodules. The use of regular brush and forceps biopsy did not increase the diagnostic yield in malignancy. Forceps biopsy might be more useful in benign diseases.

Acute bronchodilating effects of ipratropium bromide and theophylline in chronic obstructive pulmonary disease.

The bronchodilator effects of a single dose of ipratropium bromide aerosol (36 micrograms) and short-acting theophylline tablets (dose titrated to produce serum levels of 10-20 micrograms/mL) were compared in a double-blind, placebo-controlled crossover study in 21 patients with stable, chronic obstructive pulmonary disease. Mean peak forced expiratory volume in 1 second (FEV1) increases over baseline and the proportion of patients attaining at least a 15% increase in the FEV1 (responders) were 31% and 90%, respectively, for ipratropium and 17% and 50%, respectively, for theophylline. The average FEV1 increases during the 6-hour observation period were 18% for ipratropium and 8% for theophylline. The mean duration of action was 3.8 hours with ipratropium and 2.4 hours with theophylline. While side effects were rare, those experienced after theophylline use did involve the cardiovascular and gastrointestinal systems. These results show that ipratropium is a more potent bronchodilator than oral theophylline in patients with chronic airflow obstruction.

Acute upper airway injury in burn patients. Serial changes of flow-volume curves and nasopharyngoscopy.

Serial flow-volume curves and fiberoptic nasopharyngoscopy were performed in 36 patients with cutaneous burns and/or smoke inhalation. Baseline flow-volume curve patterns were abnormal in 26 (72.2%) patients, and follow-up studies demonstrated significant reductions (p less than 0.04) in inspiratory and expiratory flow rates in the 6 patients who required endotracheal intubation because of anatomic upper airway obstruction. None of the patients with stable or increased flow rate measurements required intubation. The progression of upper airway edema in 14 patients was characterized by obliteration of the aryepiglottic folds, arytenoid eminences, and interarytenoid areas by boggy, edematous tissue that prolapsed to occlude the airway. These changes correlated with an increased size of cutaneous burns (p less than 0.0001), the presence of burns of the face and neck (p less than 0.05), and more rapid intravenously administered fluid resuscitation (p less than 0.04). Anatomic and physiologic changes consistent with upper airway dysfunction occur frequently in burn victims. Progression of these abnormalities correlates with the severity and distribution of cutaneous injury and is influenced by intravenously administered fluid.

Computed chest tomography in the evaluation of hemoptysis. Impact on diagnosis and treatment.

The results of computed chest tomograms (CT) and chest roentgenograms (CR) were compared in 32 patients who presented with hemoptysis. The CT demonstrated roentgenographic abnormalities more often than CR (p less than 0.01), providing new diagnostic information in 15 patients (46.9 percent), and clarifying CR abnormalities in five (15.6 percent) others. In addition, CT correctly localized sources of bleeding in 23 (88.5 percent) of the 26 patients in whom a site was identified at bronchoscopy, while CR localization was correct in 17 (65.4 percent) (p less than 0.05). Despite this augmentation of roentgenographic yield, information derived from CT scans influenced the management of only six patients, did not obviate the need for bronchoscopy, and supplemented the combined diagnostic yield of CR and bronchoscopy in only two. Outcome was changed in one patient in whom CT had demonstrated an otherwise unrecognized malignant solitary pulmonary nodule. The chest roentgenogram and fiberoptic bronchoscopy provided all the information essential for diagnosis and therapeutic recommendations in 93.7 percent of these patients. Although the CT provided additional information in over one half of our patients, its overall impact on clinical management was small and does not support routine use of this imaging procedure in evaluation of hemoptysis. The possible role of chest CT in evaluating carefully selected patients with hemoptysis requires further study.

Comparison of the anticholinergic bronchodilator ipratropium bromide with metaproterenol in chronic obstructive pulmonary disease. A 90-day multi-center study.

The short- and long-term efficacy and safety of an inhaled quaternary ammonium anticholinergic agent, ipratropium bromide, and a beta agonist aerosol, metaproterenol, were compared in 261 nonatopic patients with chronic obstructive pulmonary disease (COPD). The study was a randomized, double-blind, 90-day, parallel-group trial. On three test days-one, 45, and 90-mean peak responses for forced expiratory volume in one second and forced vital capacity and mean area under the time-response curve were higher for ipratropium than for metaproterenol. Clinical improvement was noted in both treatment groups, especially during the first treatment month, with persistence of improvement throughout the remainder of the study. Side effects were relatively infrequent and generally mild; tremor, a complication of beta agonists, was not reported by any subject receiving ipratropium. These results support the effectiveness and safety of long-term treatment with inhaled ipratropium in COPD.

Rigid transbronchial needle aspiration biopsy for histological specimens.

Transbronchial needle aspiration of cytopathological specimens has proven useful in the diagnosis and staging of bronchogenic carcinoma, but its value in conditions requiring histologic confirmation has been hampered by the small size of the sample provided. To expand the utility of this procedure, we designed a larger (18 gauge) needle with a beveled stylet with which tissue cores for histologic study can be obtained during rigid bronchoscopy, and we have evaluated the safety and efficacy of this technique. Diagnoses of five neoplastic and three granulomatous diseases were established in eight of the ten patients with this procedure, and there were no complications. These findings suggest that transbronchial needle aspiration biopsy is relatively safe and effective, further extending the bronchoscopic approach to selected patients with mediastinal disease.