CHANGES IN RESULTS OF GALLIUM-67-CITRATE SCANNING AFTER INTERFERON THERAPY FOR CHRONIC HEPATITIS-C

Gallium-67 scanning is useful for early diagnosis and grading of inter stitial lung disease, in a study of the side effects of interferon (IF N) on the lungs of patients with chronic hepatitis C, we performed Ga- 67 scanning before and after IFN therapy. Methods: The 66 subjects who underwent at least one scanning, before IFN therapy, were 8 patients with chronic persistent hepatitis (CPH), 21 with chronic aggressive he patitis 2A (CAH-2A), 25 with chronic aggressive hepatitis 2B (CAH-2B) and 12 with cirrhosis. All had underlying hepatitis C viral infection. Of those patients, 20 were examined again within 1 mo after IFN thera py. Patients received an intravenous injection of 340 MBq Ga-67-citrat e and were imaged 72 hr later. ROIs were established for anterior view s of the lungs (Lu), liver (Li) and soft tissue of the upper arm as ba ckground (B). The counts per unit size of each region of interest were used in calculation of the ratios Lu/B and Li/B. Results: The medians of Lu/B were 2.46 in CPH, 2.56 in CAH-2A, 2.50 in CAH-2B and 2.47 in cirrhosis. These differences were not statistically significant, The m edians of WE were 6.42 in CPH, 6.14 in CAH-2A, 5.11 in CAH-2B and 4.03 in cirrhosis. The differences between the median Li/B of cirrhotic pa tients and the medians for patients with CPH, CAH-2A and CAH-2B were s ignificant, After therapy, Lu/B was higher than before in 16 of the 20 patients and lower in the four other patients; the overall rise was s ignificant (Wilcoxon rank-sum test). Li/B was higher than before in 11 of the 20 patients and lower in the nine other patients. Conclusion: IFN caused uptake of the radionuclide to increase in most patients. Th is method showed changes in the accumulation of Ga-67-citrate that cou ld have been missed if the results had been inspected by eye. IFN can cause interstitial lung disease, but unlike other drugs with this side effect, the onset seems to be gradual enough to be detected quantitat ively by Ga-67 scanning.