Rapid growth of an intact human liver transplanted into a recipient larger than the donor

Abstract

Two individuals undergoing orthotopic hepatic transplantation received livers from donors who were on average 10 kg smaller than themselves based on recipient ideal body weight. As a result, the donor livers in these 2 cases were 29%-59% smaller than would be expected had the donor liver and recipient been matched ideally. The liver grafts in the recipients steadily increased in size, as determined by serial computed tomography scanning, to achieve new volumes consistent with those that would have been expected in a normal individual of the recipient's size, sex, and age. Fasting plasma levels of amino acids, glucagon, insulin, and standard liver injury tests were monitored to determine which measure best reflected the changes observed in the size of the grafts over time. No relationship between the changes observed in any of these parameters and hepatic growth was apparent. In both cases, the liver increased in volume at a rate of approximately 70 ml/day. These data demonstrate that a small-for-size liver transplanted into a larger recipient increases in size at a rate of approximately 70 ml/day until it achieves a liver volume consistent with that expected given the recipient's size, age, and sex.

Figure 1

Liver weight in grams (A) and liver weight in grams corrected for body weight in kilograms (B] for women aged 16–50 yr grouped in 5-yr intervals. The bars represent mean values. The brackets represent the standard error of the mean. Note that liver size increases until age 26–30 and then achieves a plateau.

Figure 2

Liver weight in grams (A) and liver weight in grams corrected for body weight in kilograms (B) for men aged 16–50 yr grouped in 5-yr intervals. The bars represent mean values. The brackets represent the standard error of the mean. Note that as was the case in women, a plateau in liver mass is reached after age 26 yr.

Figure 3

Growth of an intact small-for-size normal liver transplanted into a larger recipient. The changes observed in graft size for the 2 cases reported are shown in the component parts of the figure. The ordinate for each component graph is milliliters of liver determined by CT scanning. The number in the left upper corner of each figure reflects the patient number referred to in the text.

Figure 4

Schematic figure showing the sequential changes in the ratio of aromatic amino acids to branched chain amino acids, insulin. C-peptide, and glucagon levels in case 1.

Figure 5

Schematic figure showing the sequential changes in the ratio of aromatic amino acids to branched chain amino acids, insulin, and glucagon levels in case 2.

Figure 6

Schematic figure showing the sequential changes in the ratio of AAA to BCAA, insulin, C-peptide, and glucagon in 8 patients undergoing OLT but not having a mismatch in terms of liver size. The shaded orea is the range for normal individuals; the hrockets represent the SEM. The asterisk in panel B represents the single point at which it was statistically different (p < 0.051 from that observed at time zero. In panel C, a single asterisk indicates p < 0.005, a double asterlsk indicates p < 0.05, and a cross indicates p < 0.01 from that obtained at time zero. In panel D the asterlsk identifies the two times at which the glucagon level was significantly different from the level obtained at time zero. In panel A, all points obtained after time zero are significantly different from the data obtained at time zero.