MORPHOMETRIC IMAGE-ANALYSIS AND EOSINOPHIL COUNTS IN HUMAN LIVER ALLOGRAFTS

Histology of liver allografts is the gold standard for diagnosis of ac ute cellular rejection. However, scoring the severity of rejection and distinguishing it from other infiltrations is not easy, Only one grou p has evaluated biopsies morphometrically and also suggested that eosi nophils are a specific diagnostic feature. We quantitated eosinophil c ount in 92 biopsies in a group of 25 patients and, in another group of 30 patients, used morphometric image analysis to measure the cross-se ctional area and cell density in each portal tract in day 5 protocol l iver biopsies. Rejection was diagnosed by pathological evaluation conf irmed with clinical and biochemical graft dysfunction graded histologi cally into mild or moderate-to-severe. The control groups were five pa tients with no rejection, nine patients with CMV infection, and eight biopsies in eight patients for whom the cause of the liver dysfunction was obscure. The cross-sectional area, the inflammatory cell count of each portal tract and the mean portal tract inflammatory cell density (cells/mm(2)) increased with the severity of rejection. In each case the regression coefficient was statistically significant. Correlating the mean of the total inflammatory cell count with the mean of the por tal inflammatory cell density (cell/mm(2)) gave far better separation of the mild rejection and moderate-to-severe rejection groups. Eosinop hils were specific for the presence of acute cellular rejection and in creased with the severity of rejection. They were absent in the no rej ection group, in the CMV group and in those with obscure liver dysfunc tion. The eosinophil count fell markedly following treatment of reject ion. We conclude that morphometric image analysis can be used to quant ify acute cellular rejection and that eosinophils are a specific featu re of acute cellular rejection.