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. 