Evaluation of pulmonary alveolo-capillary permeability in Type 2 diabetes mellitus: Using technetium 99mTc-DTPA aerosol scintigraphy and carbon monoxide diffusion capacity

The thickening of alveolar basement membrane is found in autopsies, along with microvascular pathologies, in Type 1 and 2 diabetes mellitus (DM). To detect the function and permeability of alveolar basement membrane, carbon monoxide diffusion capacity (DLCO) and technetium 99m-diethyltriaminepentaaceticacid (99mTc-DTPA) aerosol scintigraphy methods can be used. The aim of this study was to determine alveolar basement membrane damage using these two methods. Nineteen women and 6 men, nonsmoking, Type 2 DM cases, without any lung and/or heart disease and who had neither anemia nor obesity, made up the patient group. They were compared with six female and nine male healthy cases who had the same characteristics with the diabetes cases. All of the cases DLCO were measured by single-breath method and 99mTc-DTPA aerosol scintigraphy was performed. DLCO showed no difference between the two groups. Aerosol scintigraphy was significantly decreased in the diabetic group (P=.01). In cases with >5 years of diabetic duration (P<.01), in cases with glycolized hemoglobin (HbA1c) ≤8% (P<.05) and >8% (P<.05), and in microangiopathic cases (P<.01), alveolo-capillary permeability was significantly decreased than in the control group. Among the same groups, no significant difference could be detected for DLCO. The permeability of alveolar basement membrane can reduce in respect to diabetes duration and poor metabolic control. According to our investigation, 99mTc-DTPA aerosol scintigraphy method is more sensitive than DLCO method for determining these pathologies.