Carotid body hypertrophy in patients with cystic fibrosis and cyanotic congenital heart disease.

The carotid bodies from 71 patients ranging in age from 28 weeks' gestation to 30 years were obtained at autopsy. Patients were divided into two groups based on the presence or absence of chronic hypoxemia. There was a high correlation between the weight of individual carotid bodies in each case. Among the 12 patients with chronic hypoxemia, eight patients had carotid bodies heavier than predicted by statistical analysis. Of these eight patients, six had cystic fibrosis and two had cyanotic heart disease. Morphometric and cell population analyses of the carotid bodies from these eight patients and from those of the control population indicated that enlargement of the carotid bodies during normal or abnormal growth results from proportionate increases in lobule parenchyma and stroma. There was also an increase in the width and length of the lobules without an increase in the diameter of the cell cords or a change in the size or proportion of the chief cells. Growth and development of the carotid bodies were studied in a control group of 59 patients without chronic hypoxemia. There were no sex related differences in carotid body weights. The combined weight of the carotid bodies correlated most strongly with body weight, although there was some correlation with age and body length. A regression equation reflecting the data relating to body weight (BW) is: Combined weight of carotid bodies (in mg.) = 0.29 BW (in kg.) +3.0. Leukemic infiltrates were present in two patients with acute lymphocytic leukemia, and diffuse lymphocytic infiltration with nodule formation was present in one patient with mental retardation. Metaplastic cartilage was present in a carotid body of one patient.