Chronic eosinophilic pneumonia. A report of 19 cases and a review of the literature.

Clinical, roentgenographic and pathologic findings in patients with chronic eosinophilic pneumonia, including 19 additional cases, have been reviewed and summarized. Most patients present with subacute respiratory and constitutional symptoms and have failed to respond to therapy for presumptive pneumonia. A previous history of atopy, most often asthma, will be obtained in one-half. Eosinophilia occurs in most cases and its absence may be the major indication for lung biopsy. Although pulmonary infiltrates are more often peripheral than not, the classic "photographic negative of pulmonary edema" is seen in less than one-third of cases. Pathologic findings include an intra-alveolar and interstitial infiltrate which comprises eosinophils, histiocytes, and exudate. Bronchiolitis obliterans and eosinophilic microabscesses occur less frequently. Open-lung biopsy is preferable when atypical features prevent a confident clinical diagnosis. The exquisite responsiveness of CEP to corticosteroids should encourage use of a therapeutic trial when there is a strong clinical suspicion of the disorder. The rapid clinical response should not deter the clinician from giving a prolonged course of treatment. The differential diagnosis includes other diseases characterized by PIE and the more recently recognized bronchiolitis obliterans and organizing pneumonia, a disorder which is also marked by peripheral pulmonary infiltrates.

Congenital bronchial atresia. A report of 4 cases and a review of the literature.

The clinical, radiographic, and pathologic findings in 82 patients with congenital bronchial atresia (CBA) have been reviewed, and we have discussed 4 additional cases. Most patients are asymptomatic and come to attention because of abnormal radiographic findings of a round or lobulated perihilar, solid, or cystic mass--the mucoid impaction sign. Typically, the region distal to the mass is hyperinflated. Recently, computed tomography has been shown to be diagnostic and its use obviates the need for other more complex imaging modalities or surgical exploration. Excisional surgery has been performed to preserve lung function in younger patients, because of lack of familiarity with the entity or, as in 2 of our cases, to prevent recurrent infections. Pathologic findings include a cystic, blindly terminating, mucus-filled bronchocele without connection to the main bronchial tree, but with normal subsequent generations of bronchi. Distally there is noncollapsible hyperinflation of the corresponding lung segment or lobe as the result of collateral ventilation from the surrounding lung. The anomaly is the result of an insult to the growing bronchial tree in early development. The differential diagnosis most often includes allergic bronchopulmonary aspergillosis, but cystic bronchiectasis, bronchogenic cysts, and intrapulmonary sequestration should also be considered. Unusual features in our 4 cases included recurrent pulmonary infections in 2 patients and thoracic cage asymmetry in 1.

Respiratory bronchiolitis-associated interstitial lung disease and its relationship to desquamative interstitial pneumonia.

Respiratory bronchiolitis is a mild inflammatory reaction commonly noted in asymptomatic cigarette smokers. We reviewed 18 cases of respiratory bronchiolitis-associated interstitial lung disease (RB/ILD), which had been diagnosed on the basis of clinical evaluation and open-lung biopsy. All patients were cigarette smokers. The sex distribution of the patients was approximately equal, and their mean age was 36 years. Chest roentgenograms showed reticular or reticulonodular infiltrates in 72% of the patients. Histologically, inflammation of the respiratory bronchioles, filling of the bronchiolar lumens and surrounding alveoli with finely pigmented macrophages, associated interstitial inflammation, and mild fibrosis were noted. In most patients, respiratory improvement ensued when they stopped smoking. Because of histologic similarities to desquamative interstitial pneumonia (DIP), the 18 cases of RB/ILD were compared with 36 cases of DIP. DIP tended to occur in older persons, caused more severe symptoms, displayed ground glass infiltrates on chest roentgenograms, was characterized by more severe interstitial disease on pulmonary function tests, and was often associated with progressive respiratory disease.

Multiple cystic fibrohistiocytic tumors of the lung: report of two cases.

We describe two adults with multiple cystic fibrohistiocytic tumors of the lung that manifested as bilateral nodular opacities, cystic lesions, or both on chest roentgenograms. One patient had recurrent episodes of pneumothorax and intermittent shortness of breath; the other was asymptomatic. Open-lung biopsy specimens showed identical histologically benign fibrohistiocytic proliferations associated with formation of cysts that were lined by metaplastic bronchiolar, squamous, or type II alveolar epithelium and old hemorrhage in the cysts. In both patients, the lesions grew slowly over a period of years. These unusual multiple bilateral fibrohistiocytic tumors of the lung should be included in the differential diagnosis of bilateral cystic lesions in the lung.

Exercise alveolar-arterial oxygen pressure difference in interstitial lung disease.

Abnormality of gas exchange is best evaluated by the exercise alveolar-arterial oxygen pressure difference, P(A-a)O2. We studied the P(A-a)O2 in 168 patients with sarcoidosis, desquamative interstitial pneumonia (DIP), usual interstitial pneumonia (UIP), berylliosis, and asbestosis who were seen for clinical and disability consultations. The increase of P(A-a)O2 with exercise was greatest in UIP (mean 16 mm Hg), least in sarcoidosis (mean 1 mm Hg), and intermediate in DIP, berylliosis, and asbestosis (means 9, 9, and 7 mm Hg, respectively). The increase was best predicted by the single breath diffusing capacity (Dsb), and it occurred in patients with sarcoidosis and DIP if the Dsb was less than 50 percent predicted and in patients with the other diseases if the Dsb was less than 70 percent predicted. However, the magnitude of the increase could not be predicted from resting tests, even when multilinear regression equations were used. We conclude that for clinical evaluation of patients with interstitial lung disease, the exercise test with arterial blood gas measurement adds important information if the Dsb is less than 70 percent predicted. For disability evaluation, the invasive exercise study may be helpful when there is a wide discrepancy between clinical findings and resting physiologic studies.

A general purpose microprocessor for spirometry.

A portable, inexpensive microprocessor is described for on-line spirographic analysis of FVC and its time derivatives and MVV, using a primary flow or volume signal. Resolution is +/- 0.02 L and maximal collection time 66 seconds. Algorithms according to the Snowbird Conference recommendations include back extrapolation, "end of test" determination and the selection criteria for satisfactory tests, and best FVC, FEV1 and other flow rates. Differentiation is digital and flow-volume outputs are available. Actual, predicted and percent predicted values for children or adults are displayed, or can be printed together with an interpretation and a flow-volume loop. Four hundred tests with a Stead-Wells spirometer, a pneumotachograph and a turbinometer using an explosive decompression FVC simulator showed standard deviations of +/- 0.04 L or L/sec or less, except for peak flow. Differences between microprocessor values and tracing analyses were less than 0.04 L. MVV with a reciprocating pump equalled exactly the MVV calculated from stroke volume and frequency (r = .999) from 8 to 325 L/min. Tests of 168 patients were comparable to the calibration devices.

Crackles (rales) in the interstitial pulmonary diseases.

There is renewed interest in the classification and methods of recording adventitious pulmonary sounds. This is a study of the importance of fine crackles (rales) in the diagnosis and estimation of the severity of diffuse infiltrative pulmonary disease. Among 272 cases documented by lung biopsy, bilateral fine crackles were heard in 60 percent of those with interstitial pneumonias and asbestosis but in only 20 percent of those with sarcoidosis and other granulomatoses. These incidences were identical in 335 patients diagnosed clinically. In 322 selected ambulatory patients with chronic obstructive pulmonary disease, fine crackles were recorded in only 10 to 12 percent, while coarse crackles were not uncommon in patients with chronic bronchitis. In workers exposed to asbestos, crackles correlated with exposure. In serial studies of such workers, the occurrence of crackles alone appeared to be a random event, while among those with crackles together with one other of five criteria, almost one-half developed asbestosis within four to six years. Fine crackles correlated with pathologic severity, with radiographic honeycombing, and with physiologic abnormalities.

A radiographic classification for sarcoidosis: physiologic correlation.

The chest roentgenogram is frequently used to judge severity and course of sarcoidosis. The only widely used method for staging, suggested by Siltzbach, does not provide for such judgments. Therefore, we devised a scheme for objective description of type and quantity of opacities based on the ILO/UC Classification for the Pneumoconioses. We added a "reticulonodular" category (x y z) to the present "rounded (p q r) and "linear-irregular" (s t u) categories. We retained the 11 point scale for profusion (severity) and added notations to describe ground glass (alveolar) patterns, size of nodes, and hilar retractions. Among 211 patients, x y z (35%) and p q r (33%) opacities predominated while s t u opacities (19%) were unusual. Radiographic severity correlated best with vital capacity (rs = -0.49) and the diffusing capacity (rs = -0.32). With the Siltzbach classification these correlations were not as good (rs = -0.27 and -0.19). Siltzbach Stage III (fibrosis) was a distinct group with poor function and frequent airway obstruction. There was no correlation between radiographic appearance and pathologic severity because the latter grading, on a scale from 0 to 10, never exceeded 3. Sequential studies in 64 patients showed that, when individuals are used as their own controls, overall profusion correlated highly with physiologic changes over time.

Open biopsy for chronic diffuse infiltrative lung disease: clinical, roentgenographic, and physiological correlations in 502 patients.

Clinical, physiological, roentgenographic, and histological data concerning 502 patients who had open biopsy for chronic "interstitial" lung disease were reviewed. Mortality was 0.3%, the rate of complications was 2.5%, and the diagnostic yield was 92.2%. A modified Chamberlain approach in the second interspace is preferred for easy access to all lobes and mediastinum. Brief tube drainage is mandatory. Atelectasis and hemorrhage in the specimen are prevented by avoiding palpation and clamps, by delineating the wedge during full inflation, and by instant fixation. Customary biopsies of the tip of the lingula or middle lobe are avoided because these are common sites of inflammation, scarring, and passive congestion. Often, the most abnormal regions are biopsied apparently to aid the pathologist. Such selection has been the most important cause of meaningless histological findings and poor pathological, physiological, and roentgenographic correlations because these regions usually show end-stage disease of unrecognizable origin. Average lung is more likely to show an active and recognizable process.

Thoracic surgical problems in asbestos-related disorders.

Among 1,577 persons with asbestos exposure followed up from 3 to 30 years, 113 had thoracic surgical procedures for asbestos-related disorders. Twenty-six individuals suspected of having asbestosis with atypical features underwent open-lung biopsy; a different disease was revealed in 14. Most of the 29 patients with mesothelioma had a small thoracotomy for diagnosis only; chemotherapy in half of them proved entirely ineffective. Experience with 23 patients with bronchogenic carcinoma did not differ from that in persons not exposed to asbestos. Problems of causal relationship are discussed. Most of the 68 individuals with benign asbestos pleural effusion had no symptoms, but because of recurrence, 15 were operated on for decortication or for possible mesothelioma. Hyaline plaques often were mistaken for lung, rib, or diaphragmatic tumors, and sometimes mesothelioma was suspected. Operative intervention in the 24 patients with plaques could have been avoided by obtaining a more detailed occupational history and reviewing previous chest roentgenograms, which invariably showed identical or smaller plaques from 2 to 17 years earlier.

Asbestos exposure in buildings.

Asbestos-related diseases are dose-related. Among these, asbestosis has occurred only with the heavy exposures of the past, is a disappearing disease, and is of no concern with the very small exposures from building occupancy. A possibly increased incidence of lung cancer has been included in risk analysis, but probably is also related to high exposure in that both epidemiologic and experimental data suggest a link between the process of alveolar inflammation and fibrogenesis and carcinogenesis. The major concern has been mesothelioma in that it has occurred with much lower household and neighborhood exposure. Additionally, anxiety concerning buildings with ACM has been heightened by finding of friable asbestos in about 20% of public buildings, discovery of environmental asbestos fibers and asbestos bodies in autopsies, and demonstration of a linear relationship between exposure and lung cancer risk in occupational groups, inviting extrapolation to a much lower dose. Legislative and regulatory mandates, promotional activities of abatement companies, adverse court decisions placing the onus of repairs on asbestos manufacturers, and a "pandemic of mediagenic disease" all have contributed to panic among building owners, school boards, insurers, and others. In that there is neither clinical nor epidemiologic support for asbestos-related disease from building occupancy, risk estimates have been based on extrapolation from past experience with generally high-dose occupational exposure. However, only a few epidemiologic studies have contained quantitative estimates of exposure, and these have been measured in terms of all particles, with conversion to asbestos fibers uncertain and the fiber type and dimension largely unknown. To these uncertainties must be added the unproved assumption of a linear dose-response down to very low levels of exposure with no threshold. At the other end of the scale extrapolation has required measurements of present building exposure, and these have been revised downward as methods for collection and analysis have improved. Risk estimates in this country and abroad have assumed exposure to 0.001 f/mL, with indicated lifetime risks for cancer ranging from about 2 to 20 per 1 million students. However, these estimates have assumed mixed fiber exposure whereas most building exposure comes from chrysotile, which is much less toxic than the amphiboles.(ABSTRACT TRUNCATED AT 400 WORDS)

Chronic diffuse infiltrative lung disease. Newer approaches.

A new scheme for description of diffuse infiltrative lung diseases using the graphic terminology of the International Labour Office Classification is described. Conventions for grading the type (rounded, or "pqr," and irregular, or "stu"), severity (profusion in 12 steps), localization of opacities, and pleural disease were retained. Modifications included (a) a third group of opacities, called "xyz," corresponding to reticulonodular patterns; and (b) "ground glass" (alveolar) patterns, subdivided into seven types by character and location. In a study of 365 cases proven by open biopsy, when this scheme was used without any knowledge of clinical data, the first two radiologic diagnostic choices corresponded with the principal histologic diagnosis in 50 per cent of cases. This classification provides an understandable and quantifiable system of communication and a tool for teaching, clinical research, and epidemiologic studies.

Surgical management of emphysema.

The history of surgery for the treatment of emphysema and its complications is long and complex and, with improved understanding of the pathophysiology, most procedures have been discarded. Present clear indications for surgery are mainly large or increasing bullae that result in compression of apparently good lung tissue, and complications of bullous emphysema such as pneumothorax and infection. With localized giant bullae the results of local resection can be as dramatic as the effects of pleural drainage for tension pneumothorax. Lobectomy should not be undertaken until bullae have been removed locally and application of positive pressure has failed to reveal any expandable lung tissue--a rare situation. Resection of small bullae generally has no effect on lung function. The indications for resection of large bullae in the presence of diffuse emphysema require careful individual study. In such cases even a small increment of function may be of great clinical benefit, and there is evidence that longevity can be increased. Finally, two-stage local drainage of tension bullae may be indicated in those rare cases in which open thoracotomy cannot be considered for other reasons.

Patient work-up for bullectomy.

A localized area of hypertransradiance often leads to surgical referral. Among 608 cases, 115 were due to local lesions of airways, blood vessels, or parenchyma. Among the remaining 493 with bullae from diffuse emphysema, 21% underwent surgery. Good restoration of function occurred in patients with rapidly progressive dyspnea who did not have a bronchitic component, recurrent infections, or CO2 retention. Physiologically, preoperative findings suggestive of tension pneumothorax, including severe restriction, marked air trapping, and little ventilation/perfusion mismatch suggested good results. Favorable radiographic findings included well-defined, large air spaces without stigmata of diffuse emphysema, serial films showing rapid enlargement of bullae, and expiration films with good thoracic motion and obscuration of lung around bullae. Compressed but otherwise intact lung was best demonstrated by angiography and CT scans. Palliative bullectomy in severe diffuse emphysema sometimes had gratifying clinical results. Resection of small bullae never caused improvement. Localized giant bullae most often were associated with paraseptal or periacinar emphysema, and the best surgical results were obtained in this group.