Orthotopic liver transplants in children: change in hepatic venous Doppler wave pattern as an indicator of acute rejection.

PURPOSE To determine whether a change in hepatic venous flow pattern can be seen during hepatic graft rejection and if it is reversible with treatment. MATERIALS AND METHODS Thirty-nine children received 42 liver allografts during a 10-year span. Doppler ultrasonographic (US) recordings of hepatic venous wave patterns were reviewed. Nine children (ten grafts) with continuously monophasic flow were not included in the study. Changes from triphasic to monophasic flow were recorded and correlated with clinical findings in all 30 patients and biopsy findings in 25. Biopsy results were compared with US data recorded within 24 hours of biopsy. Standard statistical tests were conducted to assess value of Doppler US in diagnosis of graft rejection. Significance was assessed with chi(2) statistics. RESULTS Of 113 Doppler US recordings in 30 children, 74 showed an episode of change in flow from triphasic to monophasic in 27 patients; biopsy correlation existed for 39 episodes. Thirty-five episodes were due to acute graft rejection (true-positive results). Thirty-nine episodes were due to a variety of pathologic causes (determined with biopsy results for 12 and by clinical means for 27) (false-positive results). Thirty-six assessments were true-negative (US and biopsy results negative for rejection); three were false-negative. When US results were evaluated against clinical and biopsy data, analysis revealed that change to monophasic flow predicted rejection with sensitivity of 92% (35 of 38) and specificity of 48% (36 of 75). Negative predictive value of evidence of persistent triphasic flow was 92% (36 of 39). In the subgroup of US findings with biopsy correlation, specificity increased from 48% (36 of 75) to 75% (36 of 48). It was zero (0 of 27) for the group with clinical correlation only. CONCLUSION Change of hepatic venous flow pattern from triphasic to monophasic is sensitive but nonspecific for detection of graft rejection. Evidence of persistent triphasic flow helps eliminate the possibility of graft rejection with a high negative predictive value.