A 25-year-old male cigarette smoker has a history of respiratory infections and has also been found to have hematuria. A high value for diffusing capacity is noted during pulmonary function testing. This finding is consistent with which of the following disorders?
Correct Answer: intrapulmonary hemorrhage
Description: (Braunwald, 15/e, pp 1450-1451.) Carbon monoxide (CO) diffusing capacity provides an estimate of the rate at which oxygen moves by diffusion from alveolar gas to combine with hemoglobin in the red blood cells. It is interpreted as an index of the surface area engaged in alveolar-capillary diffusion. Measurement of diffusing capacity of the lung is done by having the person inspire a low concentration of carbon monoxide. The rate of uptake of the gas by the blood is calculated from the difference between the inspired and expired concentrations. The test can be performed during a single 10-second breath holding or during 1 minute of steady-state breathing. The diffusing capacity is defined as the amount of carbon monoxide transferred per minute per millimeter of mercury of driving pressure and correlates with oxygen transpo from the alveolus into the capillaries. Primary parenchymal disorders, anemia, and removal of lung tissue decrease the diffusing capacity. Conversely, polycythemia, congestive hea failure, and intrapulmonary hemorrhage tend to increase the value for diffusing capacity. In this patient, the possibility of Goodpasture syndrome would be considered.
Category:
Surgery
Get More
Subject Mock Tests
Practice with over 200,000 questions from various medical subjects and improve your knowledge.
Attempt a mock test nowMock Exam
Take an exam with 100 random questions selected from all subjects to test your knowledge.
Coming SoonGet More
Subject Mock Tests
Try practicing mock tests with over 200,000 questions from various medical subjects.
Attempt a mock test now