SUPPLEMENTARY MATERIAL

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Long-term outcomes of ABO-incompatible pediatric living donor liver transplantation
Masaki Honda, M.D., Ph.D.; Yasuhiko Sugawara, M.D., Ph.D.; Masashi Kadohisa, M.D.; Keita
Shimata, M.D.; Masataka Sakisaka, M.D., Ph.D.; Daiki Yoshii, M.D., Ph.D.; Keiichi Uto, M.D.;
Shintaro Hayashida, M.D.; Yuki Ohya, M.D., Ph.D.; Hidekazu Yamamoto, M.D., Ph.D.;
Hirotoshi Yamamoto, M.D., Ph.D.; and Yukihiro Inomata, M.D., Ph.D.; Taizo Hibi, M.D., Ph.D
Department of Transplantation and Pediatric Surgery, Postgraduate School of Medical
Sciences, Kumamoto University, Kumamoto, Japan
Corresponding author: Yasuhiko Sugawara, M.D., Ph.D.
Department of Transplantation and Pediatric Surgery, Postgraduate School of Medical
Sciences, Kumamoto University, 1-1-1 Honjo, Chuo-ku, Kumamoto, 860-8556, Japan
Tel: +81-96-373-5616, Fax: +81-96-373-5783, E-mail: yasusugatky@gmail.com
Authorship: M.H., Y.S., H.Y, and Y.I. participated in study concept and design, analysis and


interpretation of data, and critical revision of the article. M.H., M.K., S.K., M.S., D.Y., K.U., S.H.,
Y.O., H.Y., and H.Y. participated in data collection. M.H., T.H. and Y.S. participated in the writing
of the article.
Disclosure: The authors declare no funding or conflicts of interest.
Abbreviations: LDLT, living-donor liver transplantation; ABOi, ABO-incompatible; AMR,
antibody-mediated rejection; GRWR, graft-to-recipient weight ratio; POD, postoperative day;
ACR, acute cellular rejection; MMF, mycophenolate mofetil; PE, plasma exchange; CIT, cold
ischemia time; WIT, warm ischemia time; PELD, pediatric end-stage liver disease; MELD,
model for end-stage liver disease; Ig, Immunoglobulin; DSA, donor-specific antibodies
Abstract
Background: ABO-incompatible (ABOi) living donor liver transplantation (LDLT) have been


performed to compensate for donor shortage. To date, few studies have reported detailed B
cell desensitization protocols and long-term outcomes of ABOi pediatric LDLT.
Methods: Twenty-nine pediatric ABOi LDLT recipients were retrospectively analyzed. We
compared the clinical outcomes between ABOi (n = 29) and non-ABOi (n = 131) pediatric LDLT
recipients. Furthermore, we evaluated the safety and efficacy of our rituximab-based regimen
for ABOi pediatric LDLT (2 ≤ age < 18, n = 10).
Results: There were no significant differences in the incidence of infection, vascular
complications, biliary complications, and acute cellular rejection between ABOi and non-ABOi
group. The cumulative graft survival rate at 1, 3, and 5 years for non-ABOi group were 92.1%,
87.0%, and 86.1%, and those for ABOi group were 82.8%, 82.8%, and 78.2%, respectively.
Rituximab-based desensitization protocol could be performed safely, and reduced CD19+
lymphocyte counts effectively. Although rituximab-treated ABOi group showed comparable
clinical outcomes and graft survival rate, 2 patients developed antibody-mediated rejection.
Conclusions: ABOi LDLT is a feasible option for pediatric end-stage liver disease patients.
However, it should be noted that current desensitization protocol does not completely prevent
the onset of antibody-mediated rejection in several cases.


Introduction
Liver transplantation has been established as an effective treatment for end-stage liver
disease. Although considerable progress of perioperative care and the refinement of surgical
techniques have been achieved, chronic donor shortage has been a serious problem globally.
In several countries, living donor liver transplantation (LDLT) remains a major modality
because of the limited availability of deceased donor organs for sociocultural reasons.
Furthermore, liver grafts from ABO-incompatible (ABOi) donors have been used to increase the
possibilities of transplantation1,2. Pediatric patients who suffer from liver disease are no
exception to this issue.
Advanced strategies in ABOi LDLT through innovation of B cell desensitization using
intravenous immunoglobulin, intrahepatic portal and/or arterial infusion therapy, plasma
exchange, splenectomy, and anti-CD20 monoclonal antibody, rituximab have expanded the
donor pool effectively over the last 2 decades3-7.Indeed, recent studies using the induction of
rituximab have demonstrated the dramatically improved survival rate in ABOi pediatric and
adult LDLT1,8-11. However, the incidence of antibody-mediated rejection (AMR) remains an issue
that has not yet been completely resolved. In addition, several reports showed that concerns
still remain in the incidence of high prevalence rates such as biliary stricture and infectious


complications1,8,12.
To date, few studies have reported the detailed B cell desensitization protocol and
long-term outcomes of ABOi pediatric LDLT in rituximab era. Therefore, safety and efficacy of
the rituximab based protocol for ABOi pediatric LDLT are unclear. The aims of our single-center
study are to analyze the long-term outcomes of pediatric patients who underwent ABOi LDLT
and to assess the adequacy of the immunosuppressive protocol against the ABO-barrier.
Patients and methods
Study population
Between December 1998 and March 2016, 444 patients underwent 463 LDLT at Kumamoto
University Hospital. Of these, 160 pediatric LDLT recipients under the age of 18 year were
analyzed retrospectively by reviewing the clinical records. Data were collected and analyzed in
December 2016. All patients were of Asian ethnic origin. In the study population, 29 recipients
underwent ABOi LDLT. The characteristics of study population are shown in Table 1. All our
LDLT protocol received an approval from the institutional review committee. This study was
performed according to the Ethical Guidelines for Clinical Research published on April 1, 2009,
by the Ministry of Health, Labour and Welfare of Japan.


Surgical procedure
The transplant procedures in our institution have been described previously13,14. Briefly, hepatic
and portal veins were reconstructed under a surgical loupe, and hepatic arteries were
reconstructed under a microscope. Duct-to-duct biliary reconstruction was a routine procedure
except for the recipients with biliary atresia. Absolute indication of graft size reduction was that
the estimated graft-to-recipient weight ratio (GRWR) was > 4.0%. Even if the preoperative
GRWR was < 4.0%, the reduction was considered to ensure a size match.
Basic immunosuppressive regimen
The immunosuppressive regimen consisted of tacrolimus combined with low-dose steroids.
The target trough levels of tacrolimus were between 10 and 15 ng/mL in the first 2 weeks,
around 10 ng/mL in the next 2 weeks, and between 5 and 10 ng/mL thereafter. Steroids were
initiated with an injection of 10 mg/kg of methylprednisolone prior to graft perfusion during
surgery. Recipients received the intravenous injection of 1 mg/kg of methylprednisolone during
postoperative day (POD) 1-3, 0.5 mg/kg during POD 4-6, and 0.3 mg/kg at POD 7.
Subsequently they were changed to oral administration of prednisolone and were tapered off


until around 3 to 6 months. When acute cellular rejection (AVR) was suspected by a liver
function test, patients were initially treated by increasing the dose of tacrolimus. If a liver
function test showed no improvement or ACR as proven by liver biopsy, high-dose
methylprednisolone (10 mg/kg) was administered at 3 days as a steroid pulse therapy and then
the dose was tapered (Over 7-10 days totally).
Immunosuppressive protocol for ABOi pediatric LDLT
We have performed a total of 29 cases of ABOi pediatric LDLT, of which 10 cases were 2 years
of age or older. A target trough level of tacrolimus was the same as that of non-ABOi cases as
described above. Steroids were administered as same as non-ABOi cases until 1 month after
LDLT, and tapered off taking twice as much time. Oral administration of mycophenolate mofetil
(MMF; 10mg/kg twice a day) was started POD 1. In patients below the age of 2, preoperative
plasma exchange (PE) was performed in 6 out of 8 cases by 2010 in order to decrease the
anti-donor blood group antibody to <16, and in 11 cases since 2010, additional prophylaxis
protocol was not performed (Fig. 1). All of patients who were 2 years of age or older received
single dose of rituximab 2 weeks before LDLT (Three of them received at different timings).
The dose of rituximab was 300 mg/m2 for 1 patient, 375 mg/m2 for 6 patients, and 500 mg/body


for 3 patients. Of these, the first consecutive 3se patients received additional B cell
desensitization using preoperative PE, infusion therapy, and splenectomy. From 2010, we have
used a protocol without additional B cell desensitization except for rituximab. Acetaminophen
(10 mg/kg) and d-chlorpheniramine maleate (0.04 mg/kg) were orally administered before
administration of rituximab to prevent adverse events. The diagnosis of AMR was made based
on the clinical course, immunological assays and histopathological findings15,16. C4d
immunostaining was performed case by case if AMR was suspected17.
Evaluated factors
As patient characteristics, clinical data including age at transplant, sex, primary disease, donor
age, donor sex, graft type, GRWR, blood loss, cold ischemia time (CIT), warm ischemia time
(WIT), and operation time were assessed. Moreover, incidence for bacterial infection,
cytomegalovirus infection, fungal infection, vascular complication, biliary complication, ACR,
AMR, and graft survival were compared between ABOi and non-ABOi LDLT group. Bacterial
infection was defined as elevated inflammatory parameters accompanied by infected foci and
cytomegalovirus infection was evaluated by the antigenemia test. Fungal infection was
diagnosed with identification in culture or image findings accompanied by the increase of β-D


glucan. Vascular and biliary complication were defined as those requiring some intervention.
Rituximab-treated group was further evaluated in detail including pediatric end-stage liver
disease (PELD) score (under 12 years of age) or model for end-stage liver disease (MELD)
score, blood type combination, lymphocyte crossmatch test (flow cytometry), peak titer of
Immunoglobulin M (IgM) and G (IgG) isoagglutinin against donor erythrocyte antigens at
admission, at LDLT, and after transplantation, proportion of CD19+ lymphocyte cells (%) before
rituximab treatment and at LDLT, and adverse events of rituximab treatment. The clinical
course before and after AMR onset was described separately in detail.
Statistical analysis
Continuous variables were expressed as mean values ± standard deviations. Statistical
analysis was performed using the Mann-Whitney U-test or Wilcoxon signed-rank test as
appropriate for continuous data, whereas categorical variables were compared using either the
chi-square test (without the Yates correction) or Fisher’s exact test as appropriate. The
cumulative graft survival was estimated using the Kaplan-Meier product limit method. The log-
rank (Mantel-Cox) test was used for comparison of the curves. A P value of < 0.05 was
considered statistically significant; all tests were two-tailed. All statistical analyses were


performed using the GraphPad Prism 7 (GraphPad Softwarfe).
Results
Clinical characteristics
Among 160 pediatric LDLT recipients, 29 recipients underwent ABOi LDLT (Table 1). The mean
age at transplant was significantly lower in ABOi group (3.0 ± 5.2 vs. 4.6 ± 5.6 years, P =
0.040). The mean follow-up period was 60.6 ± 45.4 months in ABOi group and was 83.8 ± 55.6
months in non-ABOi group. The most common indication for ABOi LDLT was biliary atresia
(51.7%). There were no significant differences in donor-related factors including donor age and
sex between ABOi and non-ABOi group. The most used graft type was left lateral (75.9%), and
mean GRWR was 3.2 ± 3.9 in ABOi group. Operation-related factors including graft type,
GRWR, CIT, WIT, operation time, and blood loss also showed no significant differences.
Postoperative outcomes and graft survivals
There were no significant differences in the incidence of infection, vascular complications,
biliary complications, and ACR between ABOi and non-ABOi group (Table 2). Meanwhile, 2
patients (6.9%) developed AMR in ABOi group but not in non-ABOi group (P = 0.036). Next, to
elucidate the impact of rituximab treatment, we compared the clinical outcomes between


rituximab-treated and non-rituximab-treated ABOi group. Rituximab-treated 10 patients were
classified into 2 groups based on the additional B cell desensitization protocol as described.
Reflecting excessive immunosuppression, rituximab-treated ABOi group (until 2010, n = 3)
showed a higher incidence of bacterial and fungal infection compared to rituximab-treated
ABOi group (from 2010, n = 7) and non-rituximab-treated ABOi group (n = 19) (Table 3). The
cumulative graft survival rate at 1, 3, and 5 years for non-ABOi group were 92.1%, 87.0%, and
86.1%, respectively, and those for ABOi group were 82.8%, 82.8%, and 78.2%, respectively (P
= 0.375, Fig. 2A). Rituximab-treated ABOi group showed comparable graft survival rate
(80.0%, 80.0%, 66.7% at 1, 3, and 5 years with a mean follow-up of 40.7 ± 27.4 months)
compared to the non-ABOi and non-rituximab-treated ABOi group (P = 0.328, Fig. 2B). During
the study period, mortality rate in non-rituximab-treated ABOi group was 15.8%, and in
rituximab-treated ABOi group was 30.0%. The cause of death in the former group was heart
failure (in related to the primary disease, glycogen storage disease type IV), pulmonary
hypertension (in related to the primary disease, mitochondrial DNA depletion syndrome), and
interstitial pneumonia (Table S1, SDC, http://links.lww.com/TP/B555). Whereas, the cause of
death in the latter group was AMR in 2 patients and the other was multiple organ failure related
to complications of the primary disease (progressive familial intrahepatic cholestasis type 1;


PFIC1) including bleeding from the ileostomy, severe malnutrition, and chronic renal failure18.
Safety and efficacy of rituximab for ABOi pediatric LDLT
To analyze the detailed clinical course in related to the rituximab administration for pediatric
patients, we reviewed the 10 rituximab-treated ABOi LDLT recipients whose age was 2 or older
(Table 4). Mean age at LDLT was 8.6 ± 5.5 and male-female ratio was equivalent. The most
common indication for rituximab-treated ABOi LDLT was graft failure (40.0%). The original
disease was PFIC1 in Case 2 (104 months from 1st LDLT), acute liver failure in Case 3 (36
months from 1st LDLT), and biliary atresia in Cases 8 and 10 (163 and 192 months from 1st
LDLT, respectively). The cause of graft failure was chronic rejection in Cases 2, 3, 8 and
unknown in Case 10. Cases 1-3 had received PE and splenectomy and/or infusion therapy
during the perioperative period. The lymphocyte cross match test was positive for T and B cells
in Case 1, and for B cells in Cases 5 and 10. The median titers of IgM and IgG isoagglutinin at
LDLT were 1:16 (1:1-1:256), 1:8 (1:1-1:256), respectively. CD19+ lymphocyte counts were
decreased significantly after rituximab administration (24.9 ± 9.8% to 0.49 ± 0.46%, P < 0.001).
Case 2 experienced rebound elevation of the CD19+ lymphocyte counts (19.4%) and received
375mg/m2 rituximab 10 days after LDLT. When rituximab was administered, one case of
headache, rash, cough was observed, but both of symptoms were mild and it was not


necessary to stop the treatment. In addition, although significant elevation of body temperature
was observed after rituximab treatment (36.7 ± 0.4 to 37.6 ± 0.4°C, P < 0.001), which improved
promptly within 1 day.
In rituximab-treated group, 2 patients (Cases 1 and 9) developed AMR. In Case 1,
both T and B were positive in the preoperative lymphocyte crossmatch test. Although the
elevation of anti-donor type IgM and IgG could not be observed after LDLT, the patient
repeated cholangitis from the early stage of posttransplant and showed the distinctive AMR
phenotype with intrahepatic biliary complications. The patient received high dose intravenous
immunoglobulin administration and percutaneous transhepatic biliary drainage against multiple
biloma, however eventually died of graft failure 5 months after LDLT. As previously reported,
Case 9 developed streptococcal infection 13 days after rituximab and LDLT was postponed19.
CD19+ lymphocyte count decreased to 0.1% at 9 days after rituximab administration, but the
number just prior to LDLT increased to 1.2%. The patient showed an increased ascites, a
marked increase of hepatic enzyme levels, and decreased platelet levels on POD 5. Both of
the IgM and IgG anti-donor antibody titers increased to 1:1024, and the CD19+ lymphocyte
count increased to 4.1%. The liver histology showed hepatocyte ballooning, portal
inflammation, sinusoidal congestion, and complement component 4d positivity in the vascular


endothelium. Therefore, in this case, it was speculated that streptococcal infection resulted in
reactivation of B cells, which might make a foothold to trigger AMR. Despite treatment with PE,
intravenous immunoglobulin, steroid pulse therapy, and re-administration of rituximab, the
patient died with graft failure accompanied by renal failure and acute respiratory distress
syndrome 1 month after LDLT.
Discussion
In Japan, ABOi grafts have been used in 13.8% of pediatric LDLT from 1989 to 201320. Thus,
even if pediatric patients, ABOi LDLT has been implemented as an important option to
compensate for the shortage of donors. In our institution, 18.1% of pediatric LDLT was
performed using ABOi grafts and their clinical outcomes and graft survival were comparable to
non-ABOi grafts. We evaluated the clinical outcomes and the adequacy of the
immunosuppressive protocol in ABOi pediatric LDLT.
Previous literatures have reported that infants show better outcomes in ABOi LT2,21. One
possible reason is the different immune responses of infants to ABOi graft. Infants do not
produce isohemagglutinins, therefore, their anti-A and -B antibody titers remain low levels in
early childhood22. Additionally, the activation of complement system is suppressed in infants23.


Taken together, infants have less mediators in related to the AMR. In accordance with these
mechanisms, ABOi pediatric LDLT recipients whose age < 2 in our study cohort did not develop
AMR. Therefore, we believe that it is unnecessary to use rituximab in ABOi pediatric LDLT
under 2 years of age.
We have used the rituximab-based protocol in 10 pediatric ABOi LDLT recipients for B cell
desensitization. The pretransplant therapy could be performed safely without severe adverse
events, and reduced their CD19+ lymphocyte counts effectively just prior to LT. However,
regardless of the desensitization, we experienced 2 cases (Cases 1 and 9) of AMR. Case 1
developed the distinctive AMR phenotype with intrahepatic biliary complications without the
elevation of anti-donor type IgM and IgG. Characteristically, Case 1 had shown positive
lymphocyte crossmatch for T and B cells before LDLT. Importantly, Hori et al. have shown that
a positive lymphocyte crossmatch has a negative impact on LDLT possibly because of the wide
expression of HLA antigens24. As such background might affect clinical course of Case 1,
advanced immunological strategies must be considered for lymphocyte crossmatch-positive
recipients. Case 9 showed specific clinical course suggesting the streptococcal infection after
rituximab administration resulted in reactivation of B cells, which might trigger AMR19. In the
light of experience, we think that additional desensitization therapy should be considered if the


reactivation of B cells is suspected before ABOi LDLT.
Plasmapheresis is a standard procedure to reduce donor specific antibody titers, but the
titer required to prevent AMR is not defined. Egawa et al. observed no significant relationships
between plasmapheresis and clinical outcomes after ABOi adult LDLT from a Japanese
multicenter study1. The study also revealed that local infusion, splenectomy, anti-lymphocyte
antibody, and intravenous immunoglobulin had no significant impact on overall survival or AMR
incidence in rituximab-treated ABOi LDLT recipients. As these results indicate, we believe that
the most important key to prevent AMR in ABOi LT is inhibition of new antibody production.
Additionally, the procedure such as catheter insertion for local infusion, or splenectomy
increases the risk of bleeding and infection. Based on this policy, we have used a protocol
based on the administration of rituximab (patients who were 2 years of age or older),
tacrolimus, steroids, and MMF without PE, local infusion, and splenectomy since 2010 in ABOi
LDLT25.
From the viewpoint of rituximab dose, it is widely accepted that a single maximum dose of
rituximab with efficacy and safety is 375 mg/m2 for the B cell lymphoma treatment26. Recently,
Egawa et al. suggested that the dose in 300 mg/m2 or less of rituximab single administration
would be insufficient for prevention of AMR in ABOi adult LDLT27. Indeed, one patient who had


received 300 mg/m2 of rituximab showed rebound elevation of the CD19+ lymphocyte counts
after LDLT in our study cohort. Thus, the use of rituximab at sufficient dose is recommended,
while, it is worth mentioning that careful attention must be paid to the prevention of infectious
diseases.
The optimal treatment strategy for AMR after LDLT remains unclear so far. Based on a
combination of calcineurin inhibitor, corticosteroid, plasmapheresis, and B cell modulating
therapies, use of thymoglobulin is also considered as an option to disrupt key T and B cell
interactions28. In addition, in some cases, AMR can be induced by isohemagglutinin production
from plasma cells which do not express CD20. In such a case, treatment with bortezomib,
which is a proteasome inhibitor, can be considered as another option29,30. Recently,
eculizumab, which is a monoclonal antibody that blocks the complement pathway, are
successfully used for the treatment of AMR after pediatric LT31. In this report, eculizumab was
used for recipient showing refractory AMR associated with C1q-binding donor specific antibody.
Of course, retransplantation that does not miss the time should always be considered.
The precise role of donor-specific antibodies (DSA) after LT is unclear, whereas evidence is
increasing that DSA, especially those with higher mean fluorescence intensity, are associated
with both acute and chronic liver allograft rejections32-35. In our study cohort, Case 1 in


rituximab-treated ABOi group developed AMR which did not seem to be involved in anti-blood
type antibodies, therefore, involvement of DSA should be taken into consideration as the cause
of AMR. For the impact of DSA on humoral immunity in post LT follow up, more detailed
investigation will be needed, including intervention of immunosuppressive protocols. It is also
worth noting that detrimental aspect of DSA might differ between deceased donor LT and LDLT
36.
It has been well accepted that hypogammaglobulinemia is a crucial risk factor for
development of infection37. As a reminder, rituximab and immunosuppressive drugs such as
steroids and MMF are known to induce iatrogenic hypogammaglobulinemia. Although ABOi
pediatric LDLT recipients did not develop the recurrent infections related low IgG levels in our
cohort, serum IgG levels, in particular, in rituximab-treated ABOi LDLT recipients should be
monitored at least until the recovery of B cells. Proper IgG supplementation has to be done in
case a serum IgG levels is below 500mg/dL with recurrent or severe infections.
Our study has some limitations. First, it was a retrospective single center cohort study of a
relatively small patient population. However, we believe that the data from our cohort are
reliable because the treatment practices, immunosuppressive strategy, and surgical techniques
are standardized. Prospective and multi center studies are needed to clarify the feasibility of


our protocol. Second, the observation period in ABOi group, in particular in rituximab-treated
group, is shorter compared to the non-ABOi group. This difference is affected by the time of
approval of rituximab, but we believe that an observation period of over 40 months on average
is sufficient to evaluate the long-term posttransplant outcomes. Third, our study population
does not contain acute liver failure patients in rituximab-treated group. The timing of rituximab
administration is known to be related to the rebound elevation of isohemagglutinin titers38,
therefore, further investigation will be needed to detect the minimal time interval from rituximab
administration to ABOi LDLT.
In conclusion, ABOi LDLT is a feasible option for pediatric end-stage liver disease patients.
Rituximab-based protocol is a promising procedure for preventing AMR in ABOi pediatric LDLT
recipients whose age are 2 or older. However, we need to keep in mind that the current
protocol does not completely prevent the onset of AMR in several cases, and further research
is required in the future.
Table 1. Patients characteristics (n = 160)
ABOi (n = 29) Non-ABOi (n = 131) P value
Age at transplant (years) 3.0 ± 5.2 [0-16] 4.6 ± 5.6 [0-17] 0.040
Sex (male/female) 10/19 58/73 0.409
Follow up (months) 60.6 ± 45.4 83.8 ± 55.6 0.044


Primary disease
Biliary atresia 15 (51.7%) 67 (51.1%)
Metabolic disease 6 (20.7%) 13 (9.9%)
Fulminant hepatic failure 3 (10.3%) 14 (10.7%)
Malignant tumor 0 (0%) 9 (6.9%)
Graft failure 4 (13.8%) 10 (7.6%)
Others 1 (3.4%) 18 (13.7%)
Donor age (years) 34.3 ± 5.8 36.8 ± 9.6 0.317
Donor sex (male/female) 16/13 52/79 0.127
Graft type
Left lateral 22 (75.9%) 93 (71.0%)
Left 4 (13.8%) 25 (19.1%)
Right 1 (3.4%) 10 (7.6%)
Mono-segment 2 (6.9%) 3 (2.3%)
GRWR (%) 3.2 ± 3.9 2.2 ± 1.0 0.228
CIT (minutes) 73.8 ± 43.7 104.6 ± 90.0 0.208
WIT (minutes) 39.1 ± 7.5 41.5 ± 8.5 0.114
Operation time (minutes) 672.2 ± 175.9 658.8 ± 214.3 0.480
Blood loss (g/kg) 91.7 ± 157.5 80.1 ± 129.1 0.401
ABOi, ABO-incompatible; GRWR, graft-to-recipient weight ratio; CIT, cold ischemia time; WIT,
warm ischemia time.
Table 2. Clinical outcomes between ABOi and non-ABOi group
ABOi (n = 29) Non-ABOi (n = 131) P value
Bacterial infection 10 (34.5%) 33 (25.2%) 0.356
CMV infection 14 (48.3%) 42 (32.1%) 0.131


Fungal infection 1 (3.4%) 9 (6.9%) 0.691
PVS/PVT 3 (10.3%) 7 (5.3%) 0.390
HVS 1 (3.4%) 7 (5.3%) 0.999
HAT 1 (3.4%) 3 (2.3%) 0.554
Biliary complication 3 (10.3%) 24 (18.3%) 0.415
ACR 13 (44.8%) 46 (35.1%) 0.396
AMR 2 (6.9%) 0 (0%) 0.036
ABOi, ABO-incompatible; CMV, cytomegalovirus; PVS, portal vein stenosis; PVT, portal vein
thrombosis; HVS, hepatic vein stenosis; HAT, hepatic artery thrombosis; ACR, acute cellular
rejection; AMR, antibody-mediated rejection.
Table 3. Clinical outcomes between rituximab-treated and non-rituximab-treated ABOi group
Rituximab-
treated ABOi
Rituximab-treated
ABOi (from 2010,
Non-rituximab-
treated ABOi (n = 19)
P value


(until 2010, n = 3) n = 7)
Bacterial
infection
3 (100.0%) 1 (14.3%) 6 (31.6%) 0.030
CMV infection 2 (66.7%) 3 (42.9%) 9 (47.4%) 0.781
Fungal infection 1 (33.3%) 0 (0%) 0 (0%) 0.011
PVS/PVT 1 (33.3%) 1 (14.3%) 1 (5.3%) 0.308
HVS 0 (0%) 0 (0%) 1 (5.3%) 0.761
HAT 0 (0%) 1 (14.3%) 0 (0%) 0.196
Biliary
complication
1 (33.3%) 0 (0%) 2 (10.5%) 0.284
ACR 2 (66.7%) 0 (0%) 11 (57.9%) 0.023
AMR 1 (33.3%) 1 (14.3%) 0 (0%) 0.072
ABOi, ABO-incompatible; CMV, cytomegalovirus; PVS, portal vein stenosis; PVT, portal vein
thrombosis; HVS, hepatic vein stenosis; HAT, hepatic artery thrombosis; ACR, acute cellular
rejection; AMR, antibody-mediated rejection.


Table 4. Detailed outcomes of rituximab-treated ABOi pediatric LDLT patients
Case 1 2 3 4 5 6 7 8 9 10
Age at LDLT 12 12 3 5 14 2 5 14 4 16
Gender Female Female Male Male Male Male Female Female Male Female
Primary disease BA Graft failure
(PFIC1)
Graft failure
(ALF)
BA BA Methylmalonic
acidemia
Citrin
deficiency
Graft failure
(BA)
Propionic
acidemia
Graft failure
(BA)
PELD/MELD 8 20 8 5 15 -3 1 28 -1 21
Blood type combination AB→A B→O A→B A→O AB→A AB→A A→O A→O A→O AB→A
Dose of rituximab 500 mg
(365
mg/m2)
300 mg/m2375 mg/m2375 mg/m2500 mg
(330
mg/m2)
375 mg/m2375 mg/m2375 mg/m2375 mg/m2500 mg
(295 mg/m2)
Timing of rituximab (day
before LDLT)
7 14 21 14 14 14 14 14 36 14
Lymphocyte crossmatch T+B+ - - - T-B+ - - - - T-B+
PE + + + - - - - - - -
Splenectomy + + - - - - - - - +
Infusion therapy + - + - - - - - - -
Anti-donor IgM/IgG at
admission
1:64/1:64 1:128/1:128 1:256/1:256 1:64/1:64 1:16/1:16 1:32/1:32 1:128/1:32 1:128/1:64 1:64/1:32 1:128/1:64
Anti-donor IgM/IgG at LDLT 1:1/1:1 1:4/1:4 1:2/1:2 1:128/1:64 1:8/1:4 1:32/1:32 1:16/1:8 1:32/1:16 1:64/1:32 1:64/1:32
Anti-donor IgM/IgG after
LDLT
1:32/1:32 1:128/1:32 1:64/1:8 1:4/1:4 1:4/1:1 1:8/1:1 1:256/1:256 1:8/1:1 1:4096/1:8192 1:16/1:1
CD19+ lymphocyte before
rituximab (%)
34.0 9.9 33.6 36.1 25.0 21.2 20.3 19.4 12.9 37.0
CD19+ lymphocyte at LDLT
(%)
0.7 1.4 0.2 0.3 0.3 0.1 0.1 0.3 1.2 0.3
Adverse events of rituximab - - - Headache - Skin rash Cough - - -
AMR + - - - - - - - + -
Death (months) + (5) + (50) - - - - - - + (1) -
LDLT, living donor liver transplantation; BA, biliary atresia; PFIC1, progressive familial
intrahepatic cholestasis type 1; ALF, acute liver failure; PELD, pediatric end-stage liver disease;


MELD, model for end-stage liver disease; PE, plasma exchange; AMR, antibody-mediated
rejection
Figure legends
Fig. 1. Protocol of the pediatric ABOi LDLT at Kumamoto University Hospital.
Fig. 2. Cumulative graft survival rate of pediatric LDLT recipients. (A) Comparison between
ABOi and non-ABOi group. Log-rank test, P = 0.375. (B) Comparison between ABOi (age < 2),
ABOi (2 ≤ age < 18), and non-ABOi group. Log-rank test, P = 0.328.


Uncategorized References
  !"#$%&%' & &
# $()(& #$*&$ & *&%& &+,&%
&%$)Am J Transplant. -./+(
 012 ,3 & )41&125 &13*62178(
& #$%$$ & *&%& &&9:&$%+
& &%)&)%%Liver Transpl. -./+(
 &#39'3;#)%9<& &!% &9)%
& * 9 $178(& #*&%& &Transplantation.
-./+(
 &#3=%939'3>%&
%% !178(& #*&$ & *&%& &&,&
Hepatology. -./+(
  1 ?@4"#A<&$%"9&
9 ! &!% &&+&   &178& #*&
$ & *&%& &Transplantation. -./+(
  ?@3 ,3 & 4#9 9&$178(
& #*&$ & *&%& &+&)%% !
 &%*%*&%%Clin Transplant. -./+(
 B,3B &5, 9,;178(& #*&$ & *
&%& &%%#&&%9 178(9$$ & J Hepatol.
-./+(
  &<;2<&7)%%9 &) &&&178(
& #$*&$ & *&%& &&9"#J
Hepatol. -./+(
  &<;2<&178(& #1$2*&6 & 2*
&%& &:&$96%&%' &>   ;94"#Am J
Transplant. -./+(
 8$C&$@@9 !"#&178(& #
$*&$ & *&%& &+9"& !%&&
Pediatr Transplant. -./+(
 4&1B932C9 %B>$2*&%& &1 %%9


1787 $< 7+%&8#%&93 $&DJ Am Coll Surg.
-./+(
 7&,7B7;B@74%! ! %9()#)% &!
178(& #*&$ & *&%& &World J Gastroenterol.
-./+(
 8?& @1% &B6( ($#) &% &&
$*&$ & *&%& &Pediatr Transplant. -./+(

 9 '@89)@)%9$@ %91% &B& @4$ & !
!(%&! *&$ & %! *&%& &&&!&%
9&%%9&+9&%%&$  Pediatr Transplant.
-./+(
 9%> $&$& %%%$& %
9%  !% !)9 ? &&178(& #*
&%& &Liver Transpl. -./+(
 6%1,7)5#%9<5 9&%*:$ !9
7&E; &<  &2*1 !>9  )+& $ & !1&# $)(
3$$4? &Am J Transplant. -./+(
 =?  @19 ? &&$5$
& %&&&178# $)(& #*&%& &Liver
Transpl. -./+(
 8)@@ &$32*&6 & 2*&%& &! 
> %%*=&959 %%%)+ 4 $5%%
Transplant Proc. -./+(
  &$3    41&# $)($$? &!
178(& #$*&$ & *&%& &!   &
$+1% Pediatr Transplant. -./+(
 :%9B& @=2*&%& &&,&+
4%)#)9,&%2*&%& & )Hepatol Res.
-./+(
 8=792 !& &   !178(
& #*&($ & *&%& &Transplantation. -./+(



 = &;FG&$97@) ;=6* &&% !178
% &&%&& 9$& $99E% !%"&$
&% &&%Transfusion. -./+(
 =&A>7# %,$5*9 =9 )%%&$
&*9)% ! &&&!&)+($9&%Acta
Paediatr Scand. -./+(
  :  $@6 % %*)9 ) %%(9
 &&$*&($ & *&%& &DSurgery. -./+(
 @  :9$BB#=%#) !3 & 9)#)
4"#;9 1$$ &6%&%' &&178(& #2*&6 & 
2*&%& &Transplantation. 
 5  #>%<7 %%C4"#.&(56 &  &
&# $)/%%&H%(&9)! &%9! )9 9
  #$&+&&$ * &Blood. -./+(
 :%9B:  8$ %&! "#&178(
& #*&$ & *&%& &J Hepatobiliary Pancreat Sci.
-./+(
  &46C ,69&$$)B1&# $)($$? &+9%9
&*&DCurr Opin Organ Transplant. -./+(
 >& =93)<7 ' #! &# $)($$
? &&*&%& &Am J Transplant. -./+(
 25=$&=059&B37 ' #%E* 
9 ? &!*&%& &Transplant Proc. -./+(

 ; '&2,C&7A)3,1&# $)($$? &&178(
 #$*&%&&%+%%%&$* !9
Pediatr Transplant. -./
 B%93B9B> % *I ) )
 %%9&*&$ & *&%& &+&%&H& !9 
&)&? &Transplantation. -./+(
 3%11&43;>@9%&H& !$ & (%H21
&# $%&? &&$$ &$* &&178 #*
&%& &Am J Transplant. -./+(


 8J2),<B&%%&$739&I %&&&%)
$ & (%H&(21&# $%%% $99 &? &> %*
&%&Am J Transplant. -./+(
 ; '&2,)3,A&46 & (%H211&# $%1
1%% $;921 !6)%!& &1!>$2*&%& &
Transplantation. -./+(
 2*%),B&,5;%9451#%%%3#146 & (H
211&# $%&2*&A%%6%$6 & 2*&%&4&%Am
J Transplant. -./+(
 5 & C3 <5& =1 %&5&  #&&
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