Post-transplant food allergy in children is associated with liver and not with renal transplantation: a monocentric comparative study

Transplant-acquired allergy in HCT-recipients: Reference for clinical management

Transplant-acquired allergy (TAA) is well known in pediatric patients undergoing liver transplantation. Regarding allogeneic hematopoietic cell transplantation (allo-HCT), the clinical characteristics of TAA have not been fully elucidated. Clinical manifestations of TAA include eczematous dermatitis, allergic rhinitis, and asthma. It is known that allergic diseases are transferable from allergic donors to non-allergic recipients via allo-HCT. The potential mechanism is the transfer of allergen-specific memory B cells resulting in Th2-skewed allergy-specific immune responses. Retrospective studies have suggested that cord blood transplantation (CBT) and the immunosuppressant tacrolimus have a significant impact on the development of TAA. The reported prevalence varies according to study design, diagnostic methods, and study population, and the suspected allergens vary widely among individuals. Prospective cohort studies and further mechanistic investigations are warranted to provide robust evidence on the prevalence and risk factors associated with TAA.

Transplant-Acquired Food Allergy in Children

BACKGROUND

Organ transplantation in children is a vital procedure for those with end-stage organ failure, but it has been linked to the development of post-transplant allergies, especially food allergies. This phenomenon, known as transplant-acquired food allergy (TAFA), is becoming increasingly recognized, though its mechanisms remain under investigation. Pediatric transplant recipients often require lifelong immunosuppressive therapy to prevent graft rejection, which can alter immune function and heighten the risk of allergic reactions. Our review aimed to gather the latest evidence on TAFA.

METHODS

We conducted a PubMed search from 25 June to 5 July 2024, using specific search terms, identifying 143 articles. After screening, 36 studies were included: 24 retrospective studies, 1 prospective study, 2 cross-sectional researches, and 9 case reports/series.

RESULTS

Most studies focused on liver transplants in children. The prevalence of food allergies ranged from 3.3% to 54.3%. Tacrolimus, alongside corticosteroids, was the most commonly used immunosuppressive therapy. In addition to food allergies, some patients developed atopic dermatitis, asthma, and rhinitis. Allergic symptoms typically emerged within a year post-transplant, with common allergens including milk, eggs, fish, nuts, soy, wheat, and shellfish. Both IgE-mediated and non-IgE-mediated reactions were observed, with treatment often involving the removal of offending foods and the use of adrenaline when necessary.

CONCLUSIONS

Consistent immunological monitoring, such as skin prick tests and IgE level assessments, is essential for early detection and management of allergies in these patients. Understanding the link between transplantation and allergy development is crucial for improving long-term outcomes for pediatric transplant recipients.

Atopy and allergy following solid organ transplantation: A 15-year experience

AIM

There are increasing reports of atopy/allergy following solid organ transplantation, especially paediatric liver transplantation (LT) with minimal New Zealand (NZ) data. We describe the prevalence of transplant-acquired atopy and allergy (TAA) in NZ paediatric liver transplant recipients, compared to paediatric kidney and adult liver transplants.

METHODS

TAA focussed health questionnaires were sent to patients selected from the NZ transplant registry (transplanted between January 2003 and December 2017). Demographic and clinical data were also obtained from electronic health records and follow-up phone calls.

RESULTS

A total of 232 patients (62% male) participated (111 adult liver, 82 paediatric liver, 39 paediatric kidney transplant recipients). Tacrolimus was primary immunosuppression for all LT patients; with combined tacrolimus, mycophenolate and corticosteroids for kidney transplants. The number of patients who developed TAA was significantly higher (P < 0.001) in the paediatric LT group (36/82, 44%) compared to adult liver (12/111, 11%) and paediatric kidney transplants (4/39, 10%). Eczema was most common (73%), then IgE-mediated food allergy (FA, 33%), allergic rhinitis (19%) and asthma (17%). Six paediatric LT recipients developed eosinophilic oesophagitis (EoE). Egg was the most common allergen in the IgE-mediated FA group. TAAs were severe enough to warrant a switch from tacrolimus to another agent in seven paediatric LT patients. For paediatric LT patients, female gender and younger age at transplant were risk factors for developing TAA.

CONCLUSIONS

TAA is common in paediatric liver transplant recipients, with female gender and younger age at transplant being risk factors identified. This highlights the need for detailed atopic and allergy history to be incorporated in all pre-transplant assessments.

Late airway complications following pediatric liver transplantation: A case series

BACKGROUND

Late airway complications, as consequence of immunosuppression following pediatric liver transplantation are uncommonly reported.

METHODS

In this retrospective case series, we describe two young children presenting with symptoms of airway obstruction, secondary to differing pathologies in the supraglottic airway, as a result of immunosuppression following liver transplantation.

RESULTS

Case 1, a 2-year-old girl who presented with stridor 12-months following liver transplantation, was found to have a proliferative soft tissue mass involving the supraglottic larynx. Biopsies were consistent with infiltrative eosinophilic laryngitis and associated eosinophilic esophagitis. Case 2, a 12-month-old female who presented with stridor 5-months following liver transplantation, was found to have an exophytic soft tissue mass involving the supraglottis and hypopharynx. Biopsies revealed polymorphic Epstein-Barr virus (EBV) driven post-transplant lymphoproliferative disease (PTLD). Case 1 was managed with local resection and high dose oral corticosteroids. Case 2 responded to debulking of the necrotic supraglottic mass, reduction of immunosuppression and rituximab.

CONCLUSION

A high index of suspicion needs to be maintained for complications of immunosuppression for appropriate diagnosis of airway presentations following pediatric liver transplantation. Further research is necessary to improve early detection and consolidate management strategies for these airway lesions.

Mycophenolate mofetil use is associated with reduced incidence of food allergy in liver transplanted children

OBJECTIVES

The incidence of food allergy in children following liver transplantation is high and the pathogenesis is still not known. We aimed to identify risk factors for development of food allergies in liver transplant children.

METHODS

107 children and adolescents who underwent liver transplantation from 1999 to 2019 were included. Data were retrospectively collected from medical records included total and specific IgE, eosinophil cationic protein and eosinophil count 12 months after transplantation and at yearly follow up (median follow-up).

RESULTS

24/107 (22%) patients reported clinical food reactions. Median time from transplantation to debut of food allergy was 1.6 (IQR 0.6-3.3) years. Mycophenolate mofetil (MMF) was discontinued in 24/78 patients (31%) due to side effects. Children treated with MMF in addition to tacrolimus one year after transplantation reported less food allergy (12.5% vs. 37.8%, p=0.003) and sensitization to food allergens one year after transplantation (8.9% vs. 17.8%, p=0.02) than those not receiving MMF. Tacrolimus trough levels did not differ between the patients treated with MMF and those who were not. Treatment with MMF two years after transplantation was associated with less food allergy (p=0.001) and food sensitization (p=0.002), also when adjusted for age at transplantation (p=0.006 and p=0.03, respectively) or for use of basilixmab (p=0.015 and p=0.018, respectively). Basiliximab was also associated with less food allergy.

CONCLUSIONS

Use of MMF one and two years after transplantation was associated with less food allergy and sensitization against food allergens. The effect of MMF was not due to reduced trough levels of of tacrolimus. An infographic is available for this article at: https://links.lww.com/MPG/C821.

De novo Food Allergy After Pediatric Liver Transplantation: A Systematic Review

Background

Liver transplant (LT) recipients, particularly children, have an increased risk of developing de novo food allergies (FAs) after transplantation both compared to all the other transplant groups and to the general population. Little is known about the pathogenesis underlying this phenomenon and comprehensive recommendations or clinical practice guidelines are still lacking, mainly due to the scarcity of high-quality evidence.

Aim

We aimed to prepare a systematic review on de novo FA in pediatric LT recipients to assess epidemiology and risk factors, evaluate the correlation to specific food groups, describe clinical manifestations, investigate the rate of tolerance acquisition over time and report available therapeutic strategies.

Methods

We conducted this systematic review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). MEDLINE, Scopus, Web of Science, Wiley online library, Cochrane Library, and ClinicalTrials.gov databases were systematically searched for studies published from January 1980 to September 2021. All the articles were checked independently by two reviewers in two steps. A total of 323 articles were screened, and 40 were included for data extraction.

Results and Conclusions

We found that de novo FAs develop in the 15% of pediatric LT recipients, especially in the first 2 years after surgery, with higher risk related to younger age at transplantation (especially <2 years of age) and tacrolimus immunosuppression. Subjects are often allergic to multiple foods, and 15% of them suffer from anaphylaxis. The majority of patients do not spontaneously outgrow their symptoms during follow-up. The discontinuation of tacrolimus in favor of cyclosporine or the association of tacrolimus with mycophenolate have been associated with the resolution or the improvement of FA in small retrospective case series and could be considered in case of severe or multiple, difficult to manage FAs. Prospective multicenter studies are needed to confirm these findings, guide the risk-based stratification of pediatric LT recipients, and provide for high-evidence therapeutic strategies for children with de novo FA.

De Novo Food Allergy in Pediatric Recipients of Liver Transplant

ABSTRACT

Allergic and atopic conditions, including food allergy, asthma, eczema and eosinophilic disease of the gastrointestinal tract after liver transplant in previously non-allergic children have been increasingly described. After a liver transplant, children can present mild to severe reactions to food allergens (ie, from urticaria-angioedema to life-threatening anaphylactic reactions). De novo post-transplant food allergy may become clinically evident in children who undergo liver transplant between a few months and a few years of transplant. The present narrative review aims to describe the spectrum of de novo post-transplant food allergy development, the current theories of pathogenesis, risk factors and to suggest possible clinical management strategies.

Post-transplant eosinophilic gastrointestinal disorders and lymphoproliferative disorder in pediatric liver transplant recipients on tacrolimus

AIM

To examine and characterize post-transplant eosinophilic gastrointestinal disorders (PTEGID) and post-transplant lymphoproliferative disorder (PTLD) in pediatric liver transplant recipients.

METHODS

This is a single center retrospective study of all liver transplant recipients aged 0-18 years from 1999 to 2019 who received tacrolimus as their primary immunosuppressant. Demographic data and clinical/laboratory data including PTEGID, PTLD, liver transplant types, Epstein-Barr virus status, and blood eosinophil count were reviewed. Analysis was done with logistic regression and Mann-Whitney U test.

RESULTS

Ninety-eight pediatric liver transplant recipients were included with median age at transplantation of 3.3 years (IQR: 1.1-9.3). The major indication for transplantation was biliary atresia, 51 (52%) cases. Eight (8%) children had PTLD and 14 (14%) had PTEGID. Receiving liver transplantation at an age of ≤1 year was associated with developing PTEGID (OR = 11.9, 95% CI = 3.5-45.6, p < 0.001). Additionally, eosinophilic count of ≥500/μL was associated with having PTLD (OR = 10.7, 95% CI = 1.8-206.0, p = 0.030) as well as having at least one liver rejection (OR = 2.8, 95% CI = 1.2-7.0, p = 0.024). The frequency of food-induced anaphylaxis significantly increased post-transplantation (p = 0.023).

CONCLUSIONS

PTEGID and PTLD are common in this cohort and are associated with certain risk factors that help screen children to improve recipient survival. Further studies are needed to evaluate the clinical benefits of these findings.

Diarrhea in the pediatric solid organ transplantation recipient: A multidisciplinary approach to diagnosis and management

Diarrhea in the pediatric solid organ transplantation (SOT) recipient is a frequent complaint that is associated with significant morbidity and impaired quality of life. There are limited published data regarding the specific epidemiology, diagnostic evaluation, and treatment of diarrhea after SOT in children. Pediatric SOT recipients have an increased risk of developing diarrhea because of a generalized immunosuppressed state, epidemiologic exposures, and polypharmacy. There is a need to standardize the diagnostic evaluation of diarrhea in children after SOT to facilitate an accurate diagnosis and timely treatment. Herein, we review the available published data and propose a systematic, stepwise approach to the evaluation of diarrhea in this high-risk population, focusing on timely diagnosis of both infectious and non-infectious causes, in order to provide focused management. Prospective studies are needed to better assess the true prevalence, risk factors for, etiologies, and complications of diarrhea in pediatric SOT patients that will guide optimal management. Development of effective vaccines and antiviral therapies for enteric viruses may also contribute to improved outcomes.

Conversion from tacrolimus to sirolimus as a treatment modality in de novo allergies and immune-mediated disorders in pediatric liver transplant recipients

De novo PTAID may develop in pediatric solid organ transplant recipients, have a diverse spectrum, and are occasionally treatment resistant. Previous reports showed resolution of immune cytopenias in solid organ transplant recipients following replacement of the calcineurin inhibitor tacrolimus with the mTOR inhibitor sirolimus. Herein we describe a retrospective review (2000-2017) of subjects who developed PTAID in whom immunosuppression was changed to sirolimus. Eight recipients (6 males) of either liver (n = 7) or multivisceral transplant (n = 1) suffered from severe, treatment-resistant PTAID and were switched from tacrolimus to sirolimus. The median age at transplant was 1 year (range 0.5-2.4 years). Six (75%) recipients developed de novo allergy and 2 immune-mediated diseases. The median age at presentation of PTAID was 2.7 (1.4-9) years at a median of 1.3 (0.25-8) years after transplantation. The median time from PTAID presentation to conversion to sirolimus was 1.8 (0.45-10) years. Complete resolution of symptoms was seen in 4 (50%) patients after a median of 12 (range 4-24) months including 2 patients with immune-mediated disease, 1 eczema, and 1 with eosinophilic colitis. One patient with multiple food allergies had a partial response and 3 (38%) had no response. None of the 8 recipients developed sirolimus-attributed adverse events or acute rejection during a median follow-up of 5 (0.6-8) years after the conversion. Immunosuppression conversion from tacrolimus to sirolimus can be an effective therapy in patients suffering severe or treatment-resistant PTAID, suggesting a potential role for tacrolimus in the pathogenesis of PTAID.

High Frequency of Concomitant Food Allergy Development and Autoantibody Formation in Children Who Have Undergone Liver Transplantation

BACKGROUND

Allergy and other immune-mediated diseases are more frequently reported in children who have undergone liver transplantation. Furthermore, autoantibodies are also prevalent, suggesting a state of immune dysregulation in these patients. Whether or not these processes occur simultaneously in the same individual has not been studied previously.

METHODS

A cohort of 43 children who had undergone liver transplantation for nonautoimmune liver disease at median age of 1.3 years was investigated for allergy and autoimmune disease. Sensitization to food and inhalant allergens was assessed, and autoantibodies were measured.

RESULTS

The prevalence of food allergy was 26% and that of respiratory allergy was 23%, whereas 33% and 26% of the subjects were sensitized to food and inhalant allergens, respectively. Autoimmune disease (ie, autoimmune hepatitis) occurred in a single individual (2%), whereas autoantibodies were present in 44% of the children. Food allergy and autoantibodies occurred concomitantly in 19% of the children, which was almost twice the frequency expected by chance (11%, P = 0.04). Respiratory allergy and the presence of autoantibodies were unrelated (12% concurrence versus the expected 10%, P = 0.73). In the logistic regression analysis, autoantibody formation was associated with discontinued immunosuppression and food allergy, with odds ratios of 13 (P = 0.01) and 7.1 (P = 0.03), respectively.

CONCLUSIONS

In contrast to respiratory allergy, food allergy and autoantibody formation occurred together in the same children who underwent liver transplantation at a frequency higher than would be expected by chance. This may reflect an underlying immune dysregulation that impairs immune tolerance to both food allergens and autoantigens.

Transfer of peanut allergy from donor to recipient after liver transplant

31 years old female with a history of contact dermatitis, eczema, allergic rhinitis, pernicious anemia, alopecia areata and latent tuberculosis was treated concurrently with methotrexate along with isoniazid and pyridoxine. Five months into the therapy she developed acute onset jaundice progressing into fulminant liver failure with altered mentation and worsening liver function tests. Extensive workup including serological and histopathological evaluation revealed drug-induced liver injury as the etiology of her liver failure and she underwent a successful orthotropic liver transplant. On post-transplant follow-up at four months, she was noted to have an allergic reaction consisting of a perioral rash and swelling (without anaphylaxis) after receiving a kiss from her significant other who had just eaten a peanut butter chocolate. She denied any history of allergic reaction to peanuts prior to the transplant. Percutaneous skin testing revealed immediate hypersensitivity to peanut, hazelnut, and pecan believed to be acquired newly post-transplant. Further investigation revealed that the organ donor had a documented history of systemic anaphylaxis from the peanut allergy and a positive peanut-specific IgE level. Also, another parallel solid organ recipient (lung transplant) from the same organ donor experienced a serious anaphylactic reaction after peanut exposure. This is a case of food (peanut) allergy transfer from the donor to the recipient after the liver transplant. This case highlights the importance of incorporating known donor allergies as a part of pre-transplant screening, given the potentially serious consequences from the transfer of allergies to a previously anergic recipient.

Cytokine profile in children with food allergy following liver transplantation

BACKGROUND

LTX in children is associated with increased risk of food allergy, and the mechanisms underlying this are unknown. We wanted to study whether plasma cytokine profile differed in liver transplanted children, with and without food allergy, and whether it differed from untransplanted children with CLD.

METHODS

Plasma cytokines, total and specific IgE in nine patients with food allergy were compared with 13 patients without food allergy following LTX, and also with seven untransplanted patients with CLD.

RESULTS

No difference was found in the cytokine profile between liver transplanted patients with and without food allergy. Transplanted patients with food allergy having received a prescription of epinephrine had a significantly higher total IgE (2033 [234-2831] vs 10 [5-41] IU/L, P = .002) and MIP-1b (52 [37-96] vs 36 [32-39], P = .035) compared with transplanted patients without food allergy. Two patients with severe food allergy responded favorably to conversion from tacrolimus-based immunosuppression to MMF and corticosteroids with reduction in clinical symptoms, total IgE, specific IgE, IL-1ra, IL-4, RANTES, PDGF, MIP-1a, and TNFα. The transplantation group had higher levels of IL-1b, IL-5, IL-7, IL-13, GCSF, IFNγ, and MIP-1a compared with the CLD group.

CONCLUSIONS

No overall difference was found in plasma cytokine profile between patients with and without food allergy. Patients with severe food allergy had significant elevation of MIP-1b. Discontinuation of tacrolimus reduced total and specific IgE and changed plasma cytokine profile. The plasma cytokine profile in liver transplanted children was different compared with children with CLD.

Correlation between use of immunosuppressive agents and transplant-acquired allergies in renal transplant recipients

Background

Although immunosuppressive agents used in recipients of organ transplants can suppress T cell immune responses, type I allergy to ingested or inhaled allergens after organ transplantation have frequently been reported in pediatric patients. This study aims to investigate the relationship between the use of immunosuppressive agents and the transplant-acquired allergy (TAA) in adult renal transplant recipients (RTRs).

Methods

Seventy-nine RTRs treated in our hospital from February 2015 to February 2016 were interviewed for allergic diseases by using a standard questionnaire. UniCAP allergen screening tests were performed to detect total IgE and specific IgE levels before and after renal transplantation after the use of calcineurin inhibitor tacrolimus (FK506) or cyclosporin A (CsA). The follow-up visits were scheduled for 6 months, 1 year, 2 years, and 3 years after transplantation.

Results

Allergen sensitization occurred in 9 of 79 patients. Among them, the sensitization occurred in 2 cases within 6 months after renal transplantation, in 1 case from 6 months to 1 year, in 3 cases from 1 to 2 years, and in 3 cases from 2 to 3 years. The majority of sensitization was induced by inhaled allergens (n=7), among whom 3 patients (3/79, 3.8%) had a history of type I allergy, which occurred within 6 months after transplantation in 2 cases (allergic dermatitis) and from 2 to 3 years in 1 case (diarrhea after peanut allergy). The total IgE levels of RTRs using immunosuppressive agents at different time points including 6 months, 1 year, 2 years, and 3 years after renal transplantation were significantly lower than that before surgery (all P<0.05). Sensitization occurred in 8 RTRs using FK506 and in 1 patient treated with CsA (P=0.432), and allergies occurred in 3 RTRs using FK506 and were not found among CsA users (P=0.561).

Conclusions

Administration of immunosuppressive agents in adult RTRs cannot wholly prevent allergy or sensitization. Studies with larger sample sizes and more extended follow-up periods are still required to further explore the potential association between the use of FK506 and CSA and the allergies or sensitization.

Asthma, Eczema, and Food Allergy in Children Following Liver Transplantation

OBJECTIVES

To describe the prevalence and the relationship between asthma, eczema, food allergy, and rhinitis in children after liver transplantation.

STUDY DESIGN

Children who were liver transplant recipients were investigated to assess whether the high prevalence of food allergies was accompanied by eczema, rhinitis, and asthma. Furthermore, we included 56 children with chronic liver disease to explore the risk of allergy, eczema, and asthma in this group.

RESULTS

After liver transplantation, children had higher prevalence of allergic reactions to food as compared with children with chronic liver disease (P < .001). Current asthma (P = .04) and eczema (P < .02) were observed more frequently in transplanted children as compared with children with chronic liver disease. For transplanted children who had ever received tacrolimus the relative risk (RR) of asthma was 1.7 (95% CI, 1.2-2.4; P = .02) as compared with children with chronic liver disease. Transplanted children with asthma had higher rates of sensitization to food allergens than those without asthma (RR, 3.6; 95% CI, 1.3-10.3; P = .01). The most frequent food allergens associated with asthma in transplanted children were milk (RR for asthma, 3.9; 95% CI, 1.6-9.4; P < .01), eggs (RR, 2.9; 95% CI, 1.2-7.0; P = .03), and peanuts (RR, 3.7; 95% CI, 1.6-8.3; P < .01). Food allergies occurred earlier than asthma, at 1.5 years after transplantation (IQR, 0.5-3.0 years) vs 2.5 years after transplantation (IQR, 1.0-4.5 years; P < .05). Food allergies were also associated with eczema, but not with sensitization to aero-allergens or rhinitis.

CONCLUSIONS

The high risk of food allergies in children who were liver transplant recipients was associated with eczema and asthma, but not rhinitis. The most frequent food allergens associated with asthma were milk, eggs, and peanuts.

Liver-associated immune abnormalities

In recent years, the cross talk between the liver and the immune system is being uncovered, in part by studying liver involvement in primary immune deficiencies (PID) and in part by investigating the alterations of the immune system following orthotopic liver transplantation (OLT). Here we review some of the reciprocal interactions between the liver and the immune system. Patients with PID, particularly those involving inherited defects in T and B cells or innate immunity are prone to infections and inflammatory responses that often involve the liver. Omenn's syndrome, familial hemophagocytic lymphohistiocytosis, AIRE, FOXP3 and CD25 deficiencies, common variable immunodeficiency, CD40 ligand deficiency, chronic granulomatous disease and autoimmune lymphoproliferative syndrome are some of the notable PID associated with typical hepatobiliary abnormalities. Knowledge gained from studying these PID together with laboratory and histological evaluations can assist in managing PID-associated liver dysfunction. The liver itself also has important effects on the immune system, as evident from the growing experience with patients surviving OLT. Up to 40% of pediatric patients who receive OLT suffer from post transplantation allergy, autoimmunity, and immune-mediated disorders (PTAA). PTAA is more common after liver and heart transplantations than kidney transplantations. Potential contributing factors for the increased frequency of PTAA after OLT include the age of the patients, the prolonged use of tacrolimus and the reduced regulatory immune function with a shift towards a TH2 immune response. Better understanding of the mechanisms leading to the development of PTAA after OLT will also improve the management of these conditions.

De Novo Allergy and Immune-Mediated Disorders Following Solid-Organ Transplantation-Prevalence, Natural History, and Risk Factors

OBJECTIVES

To describe the prevalence, natural course, outcome, and risk factors of post-transplant de novo allergy and autoimmunity.

STUDY DESIGN

A cross-sectional, cohort study of all children (<18 years) who underwent a solid-organ transplantation, between 2000 and 2012, in a single transplant center, with a follow-up period of 6 months or more post-transplant and without history of allergy or immune-mediated disorder pretransplant.

RESULTS

A total of 626 eligible patients were screened, and 273 patients (160 males; 59%) met the inclusion criteria; this included 111 liver, 103 heart, 52 kidney, and 7 multivisceral recipients. Patients were followed for a median period of 3.6 years. A total of 92 (34%) patients (42 males, 46%) developed allergy or autoimmune disease after transplantation, with a high prevalence among liver (41%), heart (40%), and multivisceral (57%) transplant recipients compared with kidney recipients (4%; P < .001). Post-transplant allergies included eczema (n = 44), food allergy (22), eosinophilic gastrointestinal disease (11), and asthma (28). Autoimmunity occurred in 18 (6.6%) patients, presenting mainly as autoimmune cytopenia (n = 10). In a multivariate analysis, female sex, young age at transplantation, family history of allergy, Epstein-Barr virus infection, and elevated eosinophil count >6 months post-transplantation were associated with an increased risk for allergy or autoimmunity. Two patients (0.7%) died from autoimmune hemolytic anemia and hemophagocytic lymphohistiocytosis, and 52 episodes of post-transplant allergy, autoimmunity, and immune-mediated disorders (37%) did not improve over time.

CONCLUSIONS

Allergy and autoimmunity are common in pediatric liver, heart, and multivisceral transplant recipients and pose a significant health burden. Further studies are required to clarify the mechanisms behind this post-transplant immune dysregulation.

Post-transplantation Development of Food Allergies

PURPOSE OF REVIEW

The development of food allergies is increasingly being recognized as a post-solid organ transplant complication. In this article, we review the spectrum of post-transplant food allergy development and the proposed mechanisms for de novo food allergies and the clinical significance they pose.

RECENT FINDINGS

The development of new food allergies is disproportionately associated with pediatric liver transplants, where it occurs in up to 38% of select populations. The mechanism of food allergy development is not completely understood; however, it is likely promoted by unbalanced immune suppression. De novo food allergy development is a common complication of solid organ transplants with the highest risk occurring in pediatric liver transplant recipients. There are likely multiple mechanisms for food allergy development including passive transfer of membrane-bound IgE and lymphocytes from donor to recipient, as well as loss of food tolerance and active development of new food allergies. The optimal management of food allergies following organ transplants has not been well researched but may include changing the immune suppression regimen if the food allergy does not resolve without intervention.

Transplant-acquired food allergy: current perspectives

Mechanisms that regulate the tolerance to dietary proteins or the loss of this and subsequent development of disease are poorly understood. In food allergy, there is growing awareness of the urgency in understanding these events to aid in the development of next-generation therapies and interventions. This review focuses on the accumulating evidence related to food allergy that develops after transplantation. This intriguing immunological phenomenon has been described in several different types of transplant settings and to variety of different foods. We outline these studies and the evidence from them that support transplant-acquired food allergy being a process regulated by both the donor allergic status and the recipient genetics and treatments. A number of key risk factors seem prevalent throughout transplant-acquired food allergy and include type of transplant, age and general health of the recipient, modality of immunosuppression and potentially the genetics of both donor and recipient. Importantly, these studies provide a window into better general understanding of food allergy, and facilitate clearer understanding of the critical immunological and epidemiological factors needed to allow the adoptive transfer of a food-specific allergic disease from one individual to another.

Factors Associated with Development of Food Allergy in Young Children after Liver Transplantation: A Retrospective Analysis of 10 Years' Experience

BACKGROUND

Although development of food allergy after liver transplantation is most commonly described in young children, little is known about identification of young liver-transplant recipients who are at risk of food allergy.

OBJECTIVE

This study aimed to identify the types of food allergy and the risk factors for the development of food allergy after liver transplantation.

METHODS

This was a retrospective analysis of pediatric liver transplant recipients in our organ transplantation center during 2005-2015. Relevant data of all patients who underwent liver transplantation were extracted from the center's database and the medical records. Differences in patients' characteristics were evaluated for associations between food allergy and potential risk factors. Logistic regression models were used to calculate adjusted odds ratios.

RESULTS

We obtained the data of 206 patients under 36 months of age, 42 (20.4%) of whom developed food allergy after liver transplantation. The allergy was IgE-mediated-only in 30 (71.4%) and non-IgE-mediated-only in 10 (23.8%). Multivariate analysis found eczema at liver transplantation to be a significant risk factor (adjusted odds ratio [aOR] 2.41, 95% confidence interval [CI] 1.14-4.77, P < .05). Eczema increased the risk of developing IgE-mediated food allergy after liver transplantation (aOR 3.13, 95% CI 1.41-6.93, P < .01), whereas no significant association was observed with non-IgE-mediated food allergy.

CONCLUSIONS

We identified eczema at liver transplantation as a significant risk factor for the development of IgE-mediated food allergy after liver transplantation, but not non-IgE-mediated food allergy. Our findings may contribute to a better understanding of the susceptible subgroup requiring special caution and to the establishment of effective strategies for prevention.

Airway inflammation and symptoms in children following liver and heart transplantation

OBJECTIVES

To describe the upper airway endoscopic findings of children with upper airway symptoms after liver transplantation (LT) or heart transplantation (HT).

METHODS

Review of children undergoing airway endoscopy after LT or HT from 2011 to 2015 at a tertiary care pediatric hospital. Airway findings, biopsy results, immunosuppression, and Epstein-Barr virus (EBV) levels were recorded.

RESULTS

Twenty-three of 158 LT (111) and HT (47) recipients underwent endoscopy. Median time from LT to endoscopy was 9 months (range 4-25) and 31 months (range 1-108) for HT. Thirteen of 23 patients presented with upper airway symptoms, and 10/23 presented with respiratory failure or for surveillance. Thirteen patients with upper airway symptoms had abnormal findings (7 LT; 6 HT), most commonly arytenoid edema (13 patients). There were five EBV-positive biopsies (four with post-transplant lymphoproliferative disorder), and six EBV-negative biopsies with lymphocytic inflammation. One biopsy demonstrated fungal infection. Immunosuppression was decreased in seven patients, and three received steroids. There were no episodes of allograft rejection. No patients had airway symptoms at last follow-up.

CONCLUSIONS

In pediatric solid organ transplant recipients, symptoms of airway obstruction are not uncommon and should be evaluated with endoscopy. Endoscopy without symptoms is low-yield. Treatment with decreased immunosuppression improved airway symptoms.

Inflammatory Cutaneous Diseases in Renal Transplant Recipients

Kidney transplant recipients frequently suffer from skin infections and malignancies, possibly due to the effects of long-term immunosuppressive therapy. While the relationships between immunosuppression and these pathological conditions have been widely investigated, little is known about the relative incidence and characteristics of inflammatory skin diseases in this type of patient. In this study, we analyze the incidence of a number of inflammatory cutaneous diseases in a cohort of patients who underwent kidney transplantation. Although our study shows a relatively low incidence of these pathologies in transplanted patients-in agreement with the general action of immunosuppressant therapies in reducing inflammation-we scored a different efficacy of the various immunosuppressive regimens on inflammatory and autoimmune skin diseases. This information can be key for designing immunosuppressive regimens and devising accurate follow-up protocols.

Immunohistopathology of the Newly Discovered Giant Papillae Tongue Disorder in Organ-Transplanted Children

BACKGROUND

Giant papillae tongue disorder (GPTD) is a newly discovered, long-lasting clinical disorder that may develop in organ-transplanted pediatric recipients. The key feature of this disorder is the unique tongue lesion, which comprises swollen fungiform papillae. The aim of this study was to characterize the immunohistopathology of this novel inflammatory condition.

METHODS

Six organ transplanted children with GPTD were included in the study. Routine histopathology and immunohistochemical stainings for CD3, CD4, CD8, CD25, FOXP3, CD20, CD138, CD68, CD1a, CD15, CD23, and mast cell tryptase were performed.

RESULTS

Immunohistochemical analyses of the oral lesions revealed a subepithelial infiltrate that was primarily composed of CD3- and CD4-positive T cells, CD20-expressing B cells, macrophages, and CD138-positive plasma cells. The CD20-positive cells did not display the typical B cell morphology, having in general a more dendritic cell-like appearance. The CD138-expressing plasma cells were distinctly localized as a dense infiltrate beneath the accumulation of T cells and B cells. Increased numbers of CD1a-expressing Langerhans cells were detected both in the epithelium and connective tissue. Because no granulomas were observed and only single lesional eosinophils were detected, GPTD does not resemble a granulomatous or eosinophilic condition.

CONCLUSIONS

We describe for the first time the immunopathological characteristics of a novel inflammatory disorder of the oral cavity, which may develop after solid organ transplantation in children.

Raised immunoglobulin A and circulating T follicular helper cells are linked to the development of food allergy in paediatric liver transplant patients

BACKGROUND

Post-transplant food allergy (LTFA) is increasingly observed after paediatric liver transplantation (LT). Although the immunopathology of LTFA remains unclear, immunoglobulin (Ig) E seems to be implicated.

OBJECTIVE

To study humoral and cellular immunity in paediatric LT patients in search for factors associated with LTFA, and compare with healthy controls (HC) and non-transplant food-allergic children (FA).

METHODS

We studied serum Ig levels in 29 LTFA, 43 non-food-allergic LT patients (LTnoFA), 21 FA patients and 36 HC. Serum-specific IgA and IgE against common food allergens in LTFA, IgA1 , IgA2 and joining-chain-containing polymeric IgA (pIgA) were measured. Peripheral blood mononuclear cells were analysed by flow cytometry for B and T cell populations of interest.

RESULTS

Serum IgA and specific IgA were higher in LTFA compared to LTnoFA. LTFA patients had the highest proportion of circulating T follicular helper cells (cTfh). The percentage of cTfh correlated positively with serum IgA. Unique in LTFA was also the significant increase in serum markers of mucosal IgA and the decrease in the Th17 subset of CXCR5(-) CD4(+) cells compared to HC. Both LT patients exhibited a rise in IgA(+) memory B cells and plasmablasts compared to HC and FA.

CONCLUSIONS

LT has an impact on humoral immunity, remarkably in those patients developing FA. The increase in serum markers of mucosal IgA, food allergen-specific IgA and cTfh cells observed in LTFA, point towards a disturbance in intestinal immune homoeostasis in this patient group.

Management of tacrolimus-associated food allergy after liver transplantation

Increasingly, food allergy associated with tacrolimus after pediatric living-donor liver transplantation (LT) has been reported. Tacrolimus prevents the activation of T cells by blocking calcineurin, thus producing an immunosuppressive effect, but tacrolimus induces an imbalance in T-helper type 1 (Th1) and Th2 cells in the food allergy process. This report describes a case of tacrolimus-associated food allergy after pediatric living-donor LT. The patient was a 7-year-old Japanese girl who had undergone living-donor LT at 12 months of age, and whom we first saw in the clinic at age 18 months. She received immunosuppressive therapy by tacrolimus after transplantation. Atopic dermatitis developed in post-transplant month 18. Stridor, facial edema, lip swelling, and skin erythema after consuming tempura udon containing wheat occurred in post-transplant month 39, and she was subsequently diagnosed with anaphylactic shock. Eosinophilic leukocyte and serum immunoglobulin (Ig)E increased, and specific IgE was positive for some food allergens. Pharmacotherapy was therefore changed from tacrolimus to cyclosporine A, after which eosinophilic leukocyte and serum IgE decreased and atopic dermatitis improved.

Food allergies developing after solid organ transplant

The development of food allergy is an increasingly recognized form of morbidity after solid organ transplant. It occurs more commonly in liver transplant recipients, although it has also been reported in heart, lung, kidney, and intestinal transplants. Pediatric transplant recipients are more likely to develop symptoms compared to adults, and reports of frequency vary widely from 5% to 38% in pediatric liver transplant recipients. Multiple mechanisms have been proposed in the literature, although no single mechanism can yet account for all reported observations. As food allergy can have at worst potentially fatal consequences, and at best require lifestyle adjustment through food avoidance, it is important for recipients to be aware of the donor's food allergies and particularly in pediatrics, the possibility of completely de novo allergies. This review explores the recent reports surrounding food allergy after solid organ transplant, including epidemiology, proposed mechanisms, and implications for practice.

Acquired IgE-mediated food allergy after liver transplantation in children

BACKGROUND

In recent years, the number of studies regarding newly-diagnosed food allergies after liver transplantation has been increasing. In this study, we aimed to investigate the frequency, aetiology, risk factors, and severity of IgE-mediated food allergies after liver transplantation in children.

METHODS

Paediatric patients who underwent liver transplantation at Inonu University Faculty of Medicine, Organ Transplantation Institute were included in the study.

RESULTS

Forty-nine paediatric patients were enrolled in the study; 26 (53.1%) were female, the median age at transplantation was five years, and median follow-up time after transplantation was 16 months. Six patients (12.2%) developed IgE-mediated food allergies after transplantation; four had urticaria and/or angio-oedema and two developed anaphylaxis after food intake. Patients with and without IgE-mediated food allergies were similar in terms of sex, age at transplantation, comorbid atopic disease, immunosuppressant therapy with tacrolimus, and blood tacrolimus level (p>0.05 for each). Serum total IgE levels ≥100 IU/mL (p=0.02) and peripheral eosinophilia (p=0.026) were more common in the patients who developed IgE-mediated food allergies. In five of the six patients who developed IgE-mediated food allergies, reaction occurred within the first year after transplantation; the risk of developing a reaction was 2.7 times higher within the first year after transplantation than in subsequent years (95% CI, 1.546-4.914; p=0.026). No Epstein-Barr virus or cytomegalovirus infections were detected in any of the patients who developed IgE-mediated food allergies after liver transplantation.

CONCLUSION

The risk of developing IgE-mediated food allergies is approximately three times higher within the first year after transplantation than in subsequent years.

Atopic allergy and chronic inflammation of the oral mucosa in a 3-year-old boy after heart transplantation - diagnostic and therapeutic difficulties

In recent years, we have been observing an increased proportion of atopic diseases in children after solid organ transplantation. The pathogenesis of post-transplantation allergy is not completely understood and probably involves several factors, including immunosuppressive therapy. In this paper we present a case of 3-year old boy, after orthotopic heart transplantation at 6 months of age, with symptoms of food allergy associated with atopic dermatitis and changes in the orofacial area. The mentioned symptoms and elevated levels of total and specific IgE occurred with a year of transplant. Because of failure to achieve remission after typical allergy therapy we suspected that the reason of allergy in this case can be immunosuppressive therapy.

Medical management of children after liver transplantation

PURPOSE OF REVIEW

Successful outcomes in patient, graft survival, and quality of life depend on the prevention, early detection, and treatment of possible complications. The aim of the study was to highlight the common outcomes focusing on the unique features in children. Medical follow-up of children after liver transplantation includes monitoring of surgical complications: biliary and vascular, rejection, infections, posttransplant lymphoproliferative disease, other malignancies, recurrent disease, graft function, hypertension, diabetes, renal failure, among other conditions. The goal is to maintain normal graft function on minimal immunosuppression to avoid medication-induced side-effects.

RECENT FINDINGS

Recent findings include the importance of meticulous follow-up of Epstein-Barr virus and Cytomegalic virus viral load, leading to early diagnosis and improved prognosis, increased prevalence of renal toxicity, cognitive dysfunction, autoimmune, atopic and eosinophilic disease, oral hygiene and chronic hepatitis, and fibrosis of allografts.

SUMMARY

Caring for children after liver transplantation is extremely rewarding; however, careful attention must be paid to a variety of systems with understanding of the distinctiveness of pediatrics to assure optimal outcomes.

Acquired atopic disease after liver transplantation in children; similarities to and differences from adults: a preliminary study

OBJECTIVE

The aim of this study was to determine the similarities and differences in the frequency and follow-ups of newly diagnosed atopic diseases after liver transplantation in pediatric and adult patients.

MATERIALS AND METHODS

Patients who underwent liver transplants between 2005 and 2013 and who are still alive were enrolled in the study. Patients who came for checkups filled out a survey evaluating atopic diseases. Those who had an atopic disease before transplantation were excluded from the study.

RESULTS

A total of 165 patients were enrolled in this study; 114 (69.1%) were males and 29 (17.6%) were children. The average transplantation age was 40.8 (0.3-67) years, and the most frequent reason for transplantation was chronic viral hepatitis. In 22 patients, atopic diseases [allergic rhinitis in nine patients (5.5%), asthma in six patients (3.9%), atopic eczema in six patients (3.9%), food allergy in six patients (3.9%), and drug allergy in one patient (0.6%)] developed after transplantation. Atopic diseases after transplantation were more common in children (P=0.03). When the atopic diseases were examined on a case-by-case basis, there were no differences between children and adults with respect to asthma (P=0.284), allergic rhinitis (P=1.0), or atopic eczema (P=0.284), but food allergy (P=0.009) and peripheral eosinophilia (P=0.002) were more common in children. The periodicity of allergic diseases after transplantation (P=0.192) and total IgE levels (P=0.086) were similar.

CONCLUSION

Atopic diseases developed after liver transplantation and had a greater impact on children than adults. Therefore, after undergoing liver transplantation, patients should be monitored closely for signs of atopic diseases.