G. J. Walker Smith

The Role of Inflammation in Nonspecific Abdominal Aortic Aneurysm Disease

The predominant pathologic feature of abdominal aortic aneurysm is elastin destruction, and elastin destruction may be mediated by inflammation. In this investigation serial sections of abdominal aortic aneurysm specimens were selectively stained to study the relationship between inflammation and elastin degradation. In addition, soluble aortic extracts were examined for the presence of immunoglobulins. An inflammatory infiltrate was present in 8 of 10 of the abdominal aortic aneurysm specimens examined. The infiltrate was mononuclear, commonly located at the junction of the media and adventitia; it did not codistribute with loss of elastin. The presence of an inflammatory component in abdominal aortic aneurysm was associated with a large amount of immunoglobulin in soluble extracts from aneurysmal tissue compared to atherosclerotic and normal control extracts. This study further characterizes the microscopic pathology of abdominal aortic aneurysm and describes the presence of immunoglobulin in soluble tissue extracts. In addition, the possible role of inflammation in abdominal aortic aneurysm as it relates to protease expression is detailed.

Air crescent sign of invasive aspergillosis.

Pulmonary infection in immunocompromised patients is frequently difficult to diagnose. Therapy for the more common pathogens differs greatly from that for infection with unusual opportunistic organisms. However, neither of these infectious agents offers specific radiographic signs. The authors report on 4 patients with acute leukemia and invasive aspergillosis whose radiographs demonstrated a distinctive feature of one or more air crescents within an area of pulmonary infiltrate. Autopsy studies correlated the radiographic changes with an infection due to Aspergillus species fungi. While the sign is not pathognomonic for Aspergillus infection, seen in a suitable host, it would suggest the possibility of invasive aspergillosis.

Effect of Heavy Cigarette Smoking on Renal and Myocardial Arterioles

While cigarette smoking is felt to damage small vessels in organs not in direct contact with smoke, the kidney has not been considered a target organ. Sections of kidney and myocardium in 40 autopsied subjects without known disease which damage small vessels (21 smokers, 4 ex-smokers and 15 nonsmokers) were examined to determine if the percentage of intima (IP) was increased in small (less than 150 microns) and larger (150-550 microns) arterioles. In both organs and in all vessels, mean IP was significantly greater in smokers. The degree of increase did not correlate with smoking dosage (in pack-years) but did show a positive correlation with age in the kidney but not the heart. In the kidney, at all ages studied, IP was significantly increased in smokers compared to nonsmokers. We conclude that the kidney is another target organ of smoking. Whether this causes clinical disease is unknown.

Post-traumatic Pneumatocele in the Inferior Pulmonary Ligament

Pneumatocele localized to the inferior pulmonary ligament is an uncommon sequel of blunt chest trauma. Three such cases are reported and the characteristic location and appearance of the pneumatocele, as well as its benign course, are discussed. A similar radiographic appearance has been produced in cadavers by injecting air into the inferior pulmonary ligament.

Aperistalsis and esophagitis.

Aperistalsis of the esophagus was demonstrated in six patients with esophagitis. This was observed in reflux, caustic, and infectious esophagitis, and has occurred both as a transient phenomenon with no further sequelae, and as the initial manifestation of involvement in patients who subsequently suffered stricture. Based on biopsy and autopsy specimens in two cases, a possible mechanism of aperistalsis related to the damage to neurons in Auerbachs plexus is postulated. The presence of aperistalsis has been the first significant clue to esophageal inflammation in several cases.

Pulmonary artery obstruction with fibrosing mediastinitis

A 48-year-old female was found to have fibrosing mediastinitis with pulmonary artery obstruction 4 years after an episode of right upper lobe pulmonary infarction. Biopsy material from the right upper lobe obtained at the time of the initial episode suggested venous obstruction. Acquired pulmonary artery occlusion secondary to fibrosing mediastinitis is a rare entity. This patient and twelve other reported cases are contrasted.

Pulmonary granulomas in a patient with pulmonary veno-occlusive disease.

A patient with pulmonary veno-occlusive disease is described. Lung biopsy revealed noncaseating granulomas in conjunction with the typical vascular changes of this entity. This concurrence has not been previously described.

Pulmonary artery balloon counterpulsation: Safe after peripheral placement

Pulmonary artery balloon counterpulsation is a promising experimental technique for treatment of right ventricular failure. However, clinical application has been limited in that the only device presently available (the large-volume intraaortic balloon) must be placed within a synthetic graft. Because a balloon with a smaller volume (which could be placed through a peripheral vein and be contained entirely within the pulmonary artery) would make the technique feasible on a wider scale, we tested an 8-mL pulmonary artery balloon placed through the femoral vein in 12 dogs. Two groups of animals were compared. One group had the pulmonary artery balloon in place but not counterpulsating; the other had the pulmonary artery balloon in place and counterpulsating. Each group was studied for 12 hours. A variety of hemodynamic parameters were measured. Effective diastolic augmentation and systolic unloading were noted in all 6 dogs that underwent counterpulsation (5.0 +/- 1.1 mm Hg of diastolic augmentation and 9.5 +/- 1.6 mm Hg of systolic unloading). Pulmonary function, as measured by arterial blood gas sampling and pulmonary vascular resistance, was not impaired. Examination of the heart and lungs showed no detrimental pathologic effects of pulmonary artery balloon counterpulsation. Placement of the balloon through a peripheral vein with a guidewire was easy and uncomplicated. We conclude that pulmonary artery balloon counterpulsation is safe over an extended period of 12 hours in the canine model and that diastolic augmentation and systolic unloading can be produced.