The renal glomerulus in hypoxic cor pulmonale.

We measured the mean capillary tuft area by a custom-built semi-automatic technique in postmortem sections from the kidneys of 16 patients with "blue and bloated" chronic bronchitis and emphysema and in seven patients of similar age who were free of respiratory and renal disease at death. Nine bronchitic patients had received domiciliary oxygen treatment while seven had not. The mean glomerular tuft area in these treated bronchitic patients (14 200 microns2) was not significantly different from that of the untreated patients (16 900 microns2) but the tuft area in the bronchitic subjects was significantly larger than that of the non-bronchitic controls (12 100 microns2, p less than 0 . 02). There was no reduction in glomerular cellularity to suggest passive venous distension, and glomerular size was not correlated with clinical or pathological indices of cor pulmonale (including red cell mass). The arterial oxygen tension (Po2), however, was correlated with glomerular size (r = 0 . 68, p less than 0 . 01) if allowance was made for the higher Po2 of the patients receiving oxygen. The percentage of glomeruli with an identifiable juxtaglomerular apparatus also increased with increasing glomerular size. These structural changes in the kidneys of patients with severe chronic bronchitis and emphysema may reflect changes in renal salt and water handling that are potentially reversible by oxygen treatment.