Outcome of gastric emptying and gastrointestinal symptoms after liver transplantation for hereditary transthyretin amyloidosis

Abstract

Background: Hereditary transthyretin amyloid (ATTR) amyloidosis is a rare but fatal autosomal dominant condition that is present all over the world. A liver transplantation has been shown to halt the progress of the disease in selected patients and is currently considered to be the standard treatment. Gastrointestinal manifestations are common in hereditary ATTR amyloidosis and are important for the patients' morbidity and mortality. The aim of this study was to evaluate the long-term outcome of gastric emptying, gastrointestinal symptoms and nutritional status after liver transplantation for the disease.

Methods: Swedish patients with hereditary ATTR amyloidosis transplanted between 1990 and 2012 were included. A standardized method for measuring gastric emptying with a Tc(99m)-labelled meal followed by scintigraphy was utilized. Validated questionnaires were used to assess gastrointestinal symptoms and the modified body mass index (mBMI), in which BMI is multiplied by s-albumin, was used to evaluate nutritional status. Non-parametrical statistical tests were used.

Results: Gastric emptying rates and nutritional statuses were evaluated approximately eight months before and two and five years after liver transplantation, whereas gastrointestinal symptoms were assessed in median nine months before and two and nine years after transplantation. No significant change was found in gastric emptying (median half-time 137 vs. 132 vs. 125 min, p = 0.52) or nutritional status (median mBMI 975 vs. 991 vs. 973, p = 0.75) after transplantation. Gastrointestinal symptom scores, however, had increased significantly over time (median score 7 vs. 10 vs. 13, p < 0.01).

Conclusions: Gastric emptying and nutritional status were maintained after liver transplantation for hereditary ATTR amyloidosis, although gastrointestinal symptom scores had increased over time.

Figure 1

Gastric emptying scintigraphy. Graph showing the result of a normal gastric emptying scintigraphy and the variables used in the study. Lag phase from 0 to 30 min, a T₅₀ of 80 min and a retention at 90 min of approximately 38%.

Figure 2

Outcome of gastric emptying after liver transplantation. Gastric emptying was scintigraphically measured using a Tc^99m-labelled meal and the total half-time of the radioactive marker was used for the analyses. No significant change in gastric emptying half-times was found over time (p = 0.52). Only patients who had completed the scintigraphy at all three time-points were included (n = 26). P < 0.05 was regarded as statistically significant.

Figure 3

Outcome of gastrointestinal symptoms after liver transplantation. The total and lower gastrointestinal (GI) symptom scores had both increased significantly over time (p < 0.01, for both), whereas no significant change was found for upper GI symptom scores (p = 0.09). Nausea, vomiting and loss of appetite were regarded as upper GI symptoms, whereas constipation, diarrhea and fecal incontinence were regarded as lower GI symptoms. Unintentional weight loss was added to the total GI symptom category. All symptoms were evaluated with a 10-point rating scale and, thus, the maximum possible score was 70 for the total GI symptom category (dashed y axis), while only 30 for both the upper and lower GI symptom categories (solid y axis). Only patients who had completed all three sets of questionnaires were included (n = 57). P < 0.05 was regarded as statistically significant.