Severe Angioedema Caused by Banana Allergy UnderTacrolimus Immunosuppression

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.

C1-esterase inhibitor deficiency in pediatric heart transplant recipients: incidence and findings on ultrasound

BACKGROUND

Acquired angioedema of the bowel caused by a deficiency of C1-esterase inhibitor can lead to severe abdominal pain with sudden onset, mimicking an acute surgical abdomen. In contrast to hereditary angioedema, which usually manifests in childhood, acquired angioedema is broadly recognized to affect people older than 40 years.

OBJECTIVE

To determine the incidence of acquired angioedema in a cohort of pediatric heart transplant recipients and assess imaging findings on ultrasonography.

MATERIALS AND METHODS

A cohort of 207 children and adolescents who had undergone heart transplantation were assessed at regular follow-up examinations for incidence of acquired angioedema. All patients received ACE inhibitors and immune inhibitors. Control examinations carried out in 3-month intervals included history, assessment of clinical symptoms, physical examination, US of the abdomen and laboratory blood analysis. In addition, if clinical symptoms were newly encountered, children were admitted between regularly scheduled intervals. We analyzed results of abdominal US for pathological findings of the bowel, and we assessed imaging findings in children diagnosed with acquired angioedema.

RESULTS

Acquired angioedema was diagnosed in 3/207 patients (2 girls ages 16 and 17 years and 1 boy age 9 months). These children presented with sudden onset of severe abdominal pain. The bowel wall was thickened in the presence of ascites. After a mean of 72 h, abdominal pains resolved. Thickening of bowel loops dissolved and ascites disappeared.

CONCLUSION

Single episodes of acquired angioedema were encountered in 1.4% of our series of pediatric heart transplant recipients. Radiologists should be familiar with this disease so they can diagnose it on US imaging.

New-onset post-transplantation food allergy in children--is it attributable only to the immunosuppressive protocol?

New-onset post-transplantation food allergy has been described mainly after liver transplantation, and its pathogenesis was attributed to the immunomodulatory effects of tacrolimus therapy. The aim of the present study was to evaluate the association of food allergy with solid organ transplantation in our center. The medical records of children who underwent kidney transplantation and children who underwent liver or liver and kidney transplantation from 1986 to 2005 were reviewed. A total of 189 children (124 after kidney transplantation, 65 after liver or liver and kidney transplantation) received tacrolimus as part of the immunosuppressive regimen. New-onset post-transplantation food allergy was documented in four of them: two with liver transplants and two with combined kidney and liver transplants. The absence of new-onset food allergy in the children with isolated kidney transplants is compatible with other reports in the literature. This study supports the concept that the functioning liver itself, and not only tacrolimus immunosuppression, is a main contributor to food allergy in this patient population.