Hyperventilation and Effort Dyspnea in Porto-Pulmonary Bilharziasis

Thirty-one cases of portopulmonary bilharziasis with hyperventilation at rest and dyspnea on effort were subjected to a study of lung mechanics in conjunction with the clinical, respiratory and hemodynamic variations at rest and exercise. The cases were subdivided into three groups, according to the pulmonary artery pressure at rest and on exercise. There was a mild restrictive lung disease in all cases from focal interstitial fibrosis secondary to oval deposition. The lung compliance was manifestly affected, and more so on exercise, as the pulmonary artery pressures were raised. This was reflected in an increased oxygen cost of breathing. A physiologic disturbance for the resting hyperventilation and the exercise dyspnea could therefore be revealed among other causes discussed for this and similar symptomatology in other diseases.