Jagmeet S. Soin's research while affiliated with Johns Hopkins Medicine and other places

Intravascular foreign body thromboembolism and interstitial or vascular granulomata in the lungs are common sequelae to intravenous drug abuse. Early detection of such complications is important, because of the youthful population often involved. Conventional pulmonary function tests, including forced expiratory volumes, diffusion capacity for CO (DLco), chest radiograph and arterial blood gas analysis were performed in 23 narcotic addicts, most of whom had no pulmonary symptoms. The results were compared with radionuclide pulmonary function studies obtained following inhalation of 133Xe gas and injection of 99-mTc albumin microparticles. Thirteen subjects who had normal nonnuclear pulmonary function tests, including DLco and chest radiograph, demonstrated significant abnormalities of regional lung perfusion by lung scan. Of the ten subjects with abnormal DLco all had abnormal perfusion scans and five were noted to have hypoxia at rest. In addition, six of the ten subjects with abnormal DLco revealed a history of concomitant "solid pill abuse" along with heroin abuse, whereas only 2 of 13 subjects with normal DLco admitted tooccasional solid pill abuse. The perfusion lung scan is therefore a sensitive means for detection of early lung disease in narcotic addicts.

Measurement of regional lung function with radioactive xenon (133Xe) gas and normal albumin microspheres (human) labelled with technetium 99m in 18 narcotic addicts without respiratory symptoms revealed that 73% (13/18) of the subjects had abnormalities of regional perfusion. These defects were mostly diffuse and nonsegmental. Twenty-seven percent (5/18) had abnormal regional ventilation characterized by delayed clearance of inhaled133Xe. All five had used heroin parenterally for long periods (mean, 7.5 years) in large amounts (eight bags a day), and abstinence prior to the study was brief. Six subjects who had abstained from parenteral use of narcotics for more than two years had abnormalities of regional perfusion only, their ventilation being normal. Abnormal regional perfusion was probably due to foreign body granuloma and embolism in pulmonary vessels. The cause of abnormal regional ventilation is not clear.