PANLOBULAR PULMONARY-EMPHYSEMA CAUSED BY IV INJECTION OF METHYLPHENIDATE (RITALIN) - FINDINGS ON CHEST RADIOGRAPHS AND CT SCANS

OBJECTIVE. Recent reports have described severe precocious pulmonary e mphysema in persons who inject methylphenidate (crushed Ritalin tablet s) IV. We retrospectively evaluated the plain radiographic and CT feat ures in 21 such patients. MATERIALS AND METHODS. The chest radiographs , available CT scans, and clinical and pathologic data were reviewed i n 21 cases of IV Ritalin use. The patients were from 35 to 54 years ol d. Twelve patients were men, and nine were women. Emphysema was graded on the basis of findings on chest radiographs, by consensus, on a fou r-point scale as absent, mild, moderate, or severe. CT scans were avai lable for three patients, including one imaged after a single lung tra nsplantation. Autopsy results were available for four patients. Fixed inflated lung specimens and corresponding high-resolution CT scans wer e available in three cases. RESULTS. Radiographs showed pulmonary emph ysema in all cases. The distribution of disease was basilar and symmet ric. Small apical bullae were suggested in only one case. Basilar emph ysema was rated as mild in four patients, moderate in three patients, and severe in 14 patients. In 11 patients who had serial chest radiogr aphs, the basilar emphysema was noted to progress over a 2- to 7-year period. No evidence of progressive massive fibrosis was seen in any pa tient. CT scans confirmed emphysema, most severe at the lung bases. CO NCLUSION. The plain radiographic and CT findings in patients who injec t Ritalin are similar to those found in patients with al-antitrypsin d eficiency and different from the findings seen in other types of IV dr ug use. The finding of basilar pulmonary emphysema should alert the ra diologist to the possibility of IV injection of Ritalin.