Immunosuppressive therapy does not prevent the occurrence of immunoglobulin E-mediated allergies in children and adolescents with organ transplants

Atopy as an independent predictor for long-term patient and graft survival after kidney transplantation

Background

Atopy is a genetic condition predisposing individuals to develop immunoglobulin E (IgE) against common allergens through T-helper 2 (Th2) polarization mechanisms. The impact of atopy on graft survival in solid organ transplantation is unknown.

Methodology

We analyzed 268 renal allograft recipients from the Swiss Transplant Cohort Study, a prospective multicenter cohort studying patients after solid organ transplantation, with a 9-year median follow-up (IQR 3.0). We used the Phadiatop assay to measure IgE antibodies against a mixture of common inhaled allergens (grass, tree, herbs, spores, animals, and mites) to identify pre-transplantation atopic patients (>0.35 KU/L).

Results

Of 268 kidney transplant recipients, 66 individuals were atopic (24.6%). Atopic patients were significantly younger than non-atopic patients (49.6 vs 58.0 years old, P = 0.002). No significant difference was found for gender, cold/warm ischemia time, preformed donor-specific antibodies (DSA), HLA mismatches, induction and maintenance immunosuppressive therapy, CMV serostatus, or cause of kidney failure. Patient and graft survival at ten years of follow-up were significantly better in the atopic group, 95.2% versus 69.2% patient survival (P < 0.001), and 87.9% versus 60.8% graft survival (P < 0.001), respectively. A multivariate Cox analysis revealed that atopy predicted recipient and graft survival independently of age and living donor donation. Finally, we found similar rates of biopsy-proven acute cellular and antibody-mediated rejections between atopic and non-atopic recipients.

Conclusion

Atopy was associated with better long-term patient and graft survival, independently of age and living donor donation after kidney transplantation. Yet, atopy should not be used as a predictor for acute rejection.

Transfer and loss of allergen-specific responses via stem cell transplantation: A prospective observational study

BACKGROUND

Currently, no estimates can be made on the impact of hematopoietic stem cell transplantation on allergy transfer or cure of the disease. By using component-resolved diagnosis, we prospectively investigated 50 donor-recipient pairs undergoing allogeneic stem cell transplantation. This allowed calculating the rate of transfer or maintenance of allergen-specific responses in the context of stem cell transplantation.

METHODS

Allergen-specific IgE and IgG to 156 allergens was measured pretransplantation in 50 donors and recipients and at 6, 12 and 24 months in recipients post-transplantation by allergen microarray. Based on a mixed effects model, we determined risks of transfer of allergen-specific IgE or IgG responses 24 months post-transplantation.

RESULTS

After undergoing stem cell transplantation, 94% of allergen-specific IgE responses were lost. Two years post-transplantation, recipients' allergen-specific IgE was significantly linked to the pretransplantation donor or recipient status. The estimated risk to transfer and maintain individual IgE responses to allergens by stem cell transplantation was 1.7% and 2.3%, respectively. Allergen-specific IgG, which served as a surrogate marker of maintaining protective IgG responses, was highly associated with the donor's (31.6%) or the recipient's (28%) pretransplantation response.

CONCLUSION

Hematopoietic stem cell transplantation profoundly reduces allergen-specific IgE responses but also comes with a considerable risk to transfer allergen-specific immune responses. These findings facilitate clinical decision-making regarding allergic diseases in the context of hematopoietic stem cell transplantation. In addition, it provides prospective data to estimate the risk of transmitting allergen-specific responses via hematopoietic stem cell transplantation.

Management of allergy transfer upon solid organ transplantation

Allergy transfer upon solid organ transplantation has been reported in the literature, although only few data are available as to the frequency, significance, and management of these cases. Based on a review of 577 consecutive deceased donors from the Swisstransplant Donor-Registry, 3 cases (0.5%) of fatal anaphylaxis were identified, 2 because of peanut and 1 of wasp allergy. The sera of all 3 donors and their 10 paired recipients, prospectively collected before and after transplantation for the Swiss Transplant Cohort Study, were retrospectively processed using a commercial protein microarray fluorescent test. As early as 5 days posttransplantation, newly acquired peanut-specific IgE were transiently detected from 1 donor to 3 recipients, of whom 1 liver and lung recipients developed grade III anaphylaxis. Yet, to define how allergy testing should be performed in transplant recipients and to better understand the impact of immunosuppressive therapy on IgE sensitization, we prospectively studied 5 atopic living-donor kidney recipients. All pollen-specific IgE and >90% of skin prick tests remained positive 7 days and 3 months after transplantation, indicating that early diagnosis of donor-derived IgE sensitization is possible. Importantly, we propose recommendations with respect to safety for recipients undergoing solid-organ transplantation from donors with a history of fatal anaphylaxis.

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.

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.

Allergies and autoimmune disorders in children after heart transplantation

Pediatric heart transplantation requires lifelong immune suppression and may require thymectomy, both of which alter T-cell repertoires. We hypothesized that atopic and autoimmune diseases are more common in pediatric heart transplant patients than the general population, and that transplantation in early childhood increases the risk of development or worsening of atopic or autoimmune disease. A cross-sectional single-center study including 21 heart transplant patients aged ≤18 years was conducted. Data collected included age at transplant, induction, thymectomy, and development and severity of atopic or autoimmune disease. A majority (67%) reported having any atopic disease post-transplant, all of whom reported onset or worsening post-transplantation. Thymectomized patients were significantly more likely to have asthma (P = 0.018) and report asthma worsening post-transplant (P = 0.045). Patients with worsening of asthma post-transplant were transplanted at a significantly younger age (P = 0.040). ABO incompatible and ABO compatible recipients presented similarly. Anemia was common (38%) but not always clearly of autoimmune origin. Atopic diseases are common in children following heart transplantation: Compared to the general population, there is a higher prevalence of eczema (43% vs 11%) and asthma (33% vs 9%). Both thymectomy and younger age at transplant are associated with atopic disorders, possibly due to altered T-cell repertoires.

Towards precision medicine in severe asthma: Treatment algorithms based on treatable traits

Asthma is a common disease, and although its clinical manifestations may be similar among patients, recent research discoveries have shown that it consists of several distinct clinical clusters or phenotypes, each with different underlying molecular pathways yielding different treatment responses. Based on these observations, an alternative approach - known as 'precision medicine' - has been proposed for the management of patients with severe asthma. Precision medicine advocates identification of treatable traits, linking them to therapeutic approaches targeting genetic, immunological, environmental, and/or lifestyle factors in individual patients. The main "goal" of this personalised approach is to enable choosing a treatment which will be more likely to produce a beneficial response in the individual patient rather than a 'one size fits all' approach. The aim of the present review is to discuss different ways of phenotyping asthma and to provide a rationale for treatment algorithms based on principles of precision medicine.

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.

Eosinophilic density in graft biopsies positive for rejection and blood eosinophil count can predict development of post-transplant digestive tract eosinophilia

EGID is a known post-transplant complication. Its etiology has been related to antirejection medication, but other factors may also play a role as only few transplant recipients develop EGID despite standardized treatment. This study aimed to determine whether EGID is associated with rejection events and with a specific phenotype of the rejection-positive graft biopsies in children with solid organ transplant. All patients with liver, heart, and kidney transplant followed at our institution were included in the study. Digestive tract eosinophilia was more common in heart and liver recipients and was a rare event after renal transplantation. Subjects with EGID had higher incidence of rejection and elevated peripheral blood AEC. The first rejection event and high AEC values preceded EGID diagnosis in the majority of patients. Histologically, the initial rejection-positive graft biopsy revealed accentuated eosinophilia in EGID patients compared with non-EGID cohort, which correlated with higher blood eosinophil counts at the time of first rejection episode. Prominent graft tissue and peripheral blood eosinophilia prior to EGID diagnosis suggests a predisposition for eosinophil activation in patients with post-transplant digestive eosinophilic disorder. These parameters can be used as markers for subsequent development of EGID.

Food allergy: a practice parameter update-2014

This parameter was developed by the Joint Task Force on Practice Parameters, representing the American Academy of Allergy, Asthma & Immunology (AAAAI); the American College of Allergy, Asthma & Immunology (ACAAI); and the Joint Council of Allergy, Asthma & Immunology (JCAAI). The AAAAI and the ACAAI have jointly accepted responsibility for establishing "Food Allergy: A practice parameter update-2014." This is a complete and comprehensive document at the current time. The medical environment is a changing one, and not all recommendations will be appropriate for all patients. Because this document incorporated the efforts of many participants, no single individual, including those who served on the Joint Task Force, is authorized to provide an official AAAAI or ACAAI interpretation of these practice parameters. Any request for information about or an interpretation of these practice parameters by the AAAAI or ACAAI should be directed to the Executive Offices of the AAAAI, ACAAI, and JCAAI. These parameters are not designed for use by pharmaceutical companies in drug promotion.

Clinical, endoscopic, and histologic features of eosinophilic inflammation of the gastrointestinal tract in pediatric liver transplant patients

Immunosuppression during the post-transplantation period has led to dramatic outcome improvements in PLTR patients. There have been reports describing the development of food allergies and an increased predilection for development of EGI in PLTR. We aimed to identify the clinical, endoscopic and histologic features of EGI in PLTR patients. In this retrospective case series we analyzed medical record of all PLTR who underwent EGD and/or colonoscopy at our institution from 2000 to 2006. From 2000 to 2006, 32 PLTR patients underwent endoscopic evaluation. Seventeen (53%) of 32 patients were diagnosed with EGI. Endoscopic abnormalities were seen in the esophagus, stomach, and small intestine in 11 (65%), 11 (65%), and four (24%) patients, respectively. Eosinophilic inflammation was seen in the esophagus, stomach, and small intestine in 13 (76%), 10 (59%), and five (29%) patients, respectively. Nine of 17 patients underwent colonoscopy and endoscopic abnormalities were seen in four (44%) patients. Five patients (56%) had eosinophilic inflammation. In conclusion, we have characterized the clinical, endoscopic, and histologic features of EGI. Histologic and endoscopic examination reveals that, when present, EGI is often found at multiple segments along the gastrointestinal tract.

New developments in transplant-acquired allergies

Transplant-acquired allergy (TAA) was firstly described as transplant-acquired food allergy (TAFA) after bone marrow transplantations and mostly observed in a transient form. The picture is complicated by numerous case reports of TAFA after the receipt of liver grafts from donors with no documented history of food allergy. The estimated prevalence of TAFA among young children in the literature has been documented in various studies ranging from 6% to 57%. Although TAA is mostly found to be associated with liver transplantation; it has been recently reported to be related with heart, intestinal, lung and even renal transplantations in adults. Previous reviews of published cases of liver TAA misleadingly emphasized the predominance of children and the absence of TAA in cardiac, pulmonary, and renal transplant recipients. In different studies, the male/female ratio is equal. Literature data suggest that children with TAFA typically present within the first year after surgery and are typically allergic to multiple foods. The pathogenesis of TAA is not still completely understood. Most of the studies support the concept that the functioning liver itself, and not only tacrolimus immunosuppression, is one of the main contributors to TAA in these patients. In the light of recent findings, other possible mechanisms can be summarized as following: (1) the recovery of delayed type hypersensitivity; (2) late manifestation of food allergy; (3) intestinal injury as well as inhibition of cellular energy production by tacrolimus; and (4) transfer of food-specific IgE or lymphocytes. Thus, interplay between hematopoietic cells from the transplanted organ and recipient specific factors (e.g., younger age and atopic background) seem to underlie the development of TAA. Most patients will have symptomatic improvement following reduced immunosuppression and an appropriately restricted diet. Nevertheless, some studies suggest that atopic diseases occur in some of pediatric liver transplant recipients, with manifestations including food allergy, eczema, allergic rhinitis, and asthma. More studies would be needed including greater number of patients to determine whether TAA is transient or not in pediatric/adult solid organ recipients.

Novel developments in the mechanisms of immune tolerance to allergens

Allergy is the result of a disbalanced immune response to environmental innocuous antigens. Despite of accumulating data to define the pathomechanisms that take place in case of allergic diseases a detailed understanding of sequence of events that lead to the "normal" scenario of tolerance development are still under debate. Allergen-specific immunotherapy is the only causal treatment of allergic diseases. It modifies the immune response to a particular antigen to achieve tolerance against the symptom-causing allergen. This process is considered to mirror physiological peripheral tolerance induction. A number of immunological changes have been described to occur under allergen immunotherapy, including the generation of allergen-specific regulatory T cells, the induction of allergen-specific IgG4, an increase in the Th1/Th2 cytokine ratio and decreased activation and function of effector cells such as mast cells, basophils and eosinophils.

Presentation of atopic disease in a large cohort of pediatric liver transplant recipients

Atopic disease occurs in solid organ transplant recipients with an increasingly recognized frequency. The time course for the development of these atopic diseases in liver transplantation has not been described. The objective was to characterize the atopic manifestations of children receiving chronic immunosuppression after orthotopic liver transplantation (OLT). Chart review and follow-up questionnaire were utilized for 176 OLT pediatric recipients at a single institution for manifestations of allergic disease. Atopic disease was present in 25 (14.2%) patients. Median age at transplant was 16 months with a median follow-up of 63 months. Food allergy and non-food related atopic symptoms presented at a median of 11.5 (IQR, 6-28) and 19 (IQR, 5-41) months post-transplantation, respectively. The median age at transplant of the non-atopic children was 72 months, higher than patients with atopy (p < 0.001). Food allergy and atopic skin disease symptoms were present in 40% and 56% of cases, respectively. Asthma, allergic rhinitis, or both were found in 66% of cases. The onset of symptoms of food allergy and eczema (median, 12 months post-transplantation) preceded symptoms of allergic rhinitis and asthma. (median of 27 and 30 months post-transplantation, respectively). Atopy occurs in ∼14% of pediatric liver transplant recipients, with manifestations including food allergy, eczema, allergic rhinitis, and asthma.

Non-atopic IgE and eosinophil cationic protein after allogeneic hematopoietic stem cell transplantation in children

Allogeneic hematopoietic stem cell transplantation (HSCT) in childhood is associated with severe pulmonary complications, but the pathophysiologic mechanisms remain unclear. Our aim was to evaluate the association of total and specific IgE, eosinophil cationic protein (ECP) and eosinophilia in HSCT recipients with pulmonary complications. We prospectively measured total and specific serum IgE, eosinophils, and ECP before and 28, 100, and 180 days after HSCT. We included 30 children (age 2-17 years) undergoing HSCT. Nine patients had a history of previous atopy without being associated with pulmonary complications after HSCT until day +360. Specific IgE levels showed a decline after HSCT, associated with the absence of allergy symptoms, suggesting a reduction of atopy. Elevated total serum IgE levels occurred in seven patients on day +28 after HSCT. This elevation did not coincide with allergy symptoms. ECP showed no correlation with total allergy symptoms, eosinophilia, IgE levels, or pulmonary complications. There was a significant correlation (p = 0.0367) between ECP levels on day +28 and concurrent acute graft-versus-host disease (GvHD). Non-atopic serum ECP and IgE levels are elevated on day +28 after HSCT in children, with ECP showing a potential relation to acute GvHD.

Long term outcome of acquired food allergy in pediatric liver recipients: a single center experience

Food induced sensitization has been reported in pediatric liver recipients. However long term follow up has not been established so far.We report here our experience regarding 3 pediatric patients who developed acquired food allergy after liver transplantation. The first patient suffered from persistent diarrhea and eczema. The second one presented with abdominal pain with no signs of rejection, abdominal discomfort, vomiting when ingesting milk proteins and responded well to the elimination diet. The third patient presented with facial angioedema and hoarseness of voice. She had multiple food allergies and reacted to milk, egg and sesame. All the patients had elevated total Immunoglobulin E (IgE) and elevated specific IgE antibodies to the implicated food allergens. The first patient presented clinical manifestations of allergy when she was 19 months old. The second patient became allergic at the age of 16 and the third patient at the age of 3. The symptoms of food allergy persisted for 8 years in the first case and for 2 years in the other two cases. Low levels of specific IgE antibodies to the implicated food allergens and an enhanced T-helper 1 cell immune response toward interferon-gamma production were markers of tolerance acquisition. The long term prognosis in our cases was excellent. Food allergy resolved in all the patients. The long term prognosis of acquired food allergy after liver transplantation is currently obscure. More studies would be needed including greater number of patients to determine whether acquired food allergy is transient in pediatric liver recipients.

Eosinophilic-Crohn overlap colitis and review of the literature

Eosinophilic colitis is an idiopathic inflammation of the alimentary canal and is characterized by infiltration of the intestinal wall by eosinophils, massive submucosal edema, and peripheral eosinophilia. However, the presence of eosinophils in a colon biopsy requires thorough searching for secondary causes and eosinophilic colitis remains a diagnosis of exclusion. A 67-year-old male patient underwent a diagnostic ileocolonoscopy because of recurrent episodes of diarrhea for the last six months. Colonoscopy revealed a normal terminal ileum while in the entire colon an erythematous mucosa with very slight edema on a continuous pattern that was more pronounced in the left colon. The laboratory workup demonstrated eosinophils slightly elevated, biochemical tests were unremarkable and further clinical and laboratory workup was unremarkable. Histology showed overlapping findings of eosinophilic colitis and Crohn's colitis. Patient started on mesalazine 2.4 with very good results. A review of the literature shows that the spectrum of eosinophil involvement in inflammatory bowel disease as well as in eosinophilic colitis is largely varying, including also some exceptional cases that parallel the case described herein.

Allergic sensitization in kidney-transplanted patients prevails under tacrolimus treatment

BACKGROUND

Type I allergies have repeatedly been reported after solid organ transplantation despite T cell-targeted immunosuppressive therapy. A causal relationship with tacrolimus has been proposed.

OBJECTIVE

The present study directly compared the occurrence of allergic sensitization and disease under tacrolimus- vs. cyclosporin A-based immunosuppressive therapy.

METHODS

The prevalences of IgE-mediated sensitization and allergy were assessed in a cross-sectional study of kidney-transplanted adults receiving tacrolimus (n = 100) or cyclosporin A (n = 100).

METHODS

included a standardized questionnaire, skin prick test and measurement of total and specific IgE against common nutritive and inhalant allergens. Results The prevalence of sensitization was significantly higher in the tacrolimus- than in the cyclosporin A-treated group (34%, n = 34, vs. 20%, n = 20; P = 0.026). The rate of clinically relevant allergy in patients receiving tacrolimus was twice that in patients receiving cyclosporin A (15%, n = 15, vs. 8%, n = 8; P = 0.12). No other factor (age, serum drug level, concomitant immunosuppressive medication, time since transplantation, underlying disease) was found to have an influence on sensitization or allergy prevalence (logistic regression).

CONCLUSION AND CLINICAL RELEVANCE

Our results suggest that post-transplant immunosuppression with tacrolimus is associated with an increased occurrence of IgE-mediated sensitization and probably manifestation of allergic disease, which has to be treated specifically despite immunosuppressive therapy.

Impact of systemic immuno-suppression after solid organ transplantation on allergen-specific responses

INTRODUCTION

  The immunosuppressive therapy in solid organ transplantation targets mainly the T- and B-cell-mediated immune response. However, there is evidence that it neither suppresses sensitization nor clinical manifestation of allergic diseases in organ-transplanted patients.

OBJECTIVE

  This study addresses the question whether allergen-specific responses are altered by systemic immunosuppression via negative effects on the T-regulatory cell compartment and a more pronounced suppression on Th1-type T-cell responses.

MATERIAL AND METHODS

  Peripheral blood mononuclear cells from 65 solid organ-transplanted (kidney, liver, lung) children, adolescents, and young adults and 18 healthy, matched controls were included, and their clinical and sensitization status assessed. Allergen-specific proliferation, intracellular cytokine production, frequency of forkhead box P3 (FOXP3)+ CD3+ CD4+ CD25(high) cells, mRNA expression of IL-10, transforming growth factor (TGF)-β and FOXP3 (real-time RT-PCR) of peripheral blood mononuclear cells or bronchoalveolar lavage fluid (BAL)-derived cells, and the inhibitory capacity of T-reg cells were investigated.

RESULTS

  Immunosuppression led to a significantly altered regulatory marker profile expressed by enhanced TGF-β mRNA production and a reduced frequency of FOXP3+ CD4+ CD3+ cells in solid organ transplanted individuals. FOXP3 expression in BAL cells of lung-transplanted patients was significantly decreased. Allergen-specific proliferation was not significantly altered despite long-term immunosuppression. However, suppression of allergen-specific responses via the T-regulatory cell fraction was deficient in immunosuppressed individuals.

CONCLUSION

  The results suggest an insufficient control of allergen-specific responses via the Treg-cell compartment under systemic immunosuppression.

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.

Endotyping asthma: new insights into key pathogenic mechanisms in a complex, heterogeneous disease

Clinical asthma is very widely assumed to be the net result of excessive inflammation driven by aberrant T-helper-2 (Th2) immunity that leads to inflamed, remodelled airways and then functional derangement that, in turn, causes symptoms. This notion of disease is actually poorly supported by data, and there are substantial discrepancies and very poor correlation between inflammation, damage, functional impairment, and degree of symptoms. Furthermore, this problem is compounded by the poor understanding of the heterogeneity of clinical disease. Failure to recognise and discover the underlying mechanisms of these major variants or endotypes of asthma is, arguably, the major intellectual limitation to progress at present. Fortunately, both clinical research and animal models are very well suited to dissecting the cellular and molecular basis of disease endotypes. This approach is already suggesting entirely novel pathways to disease-eg, alternative macrophage specification, steroid refractory innate immunity, the interleukin-17-regulatory T-cell axis, epidermal growth factor receptor co-amplification, and Th2-mimicking but non-T-cell, interleukins 18 and 33 dependent processes that can offer unexpected therapeutic opportunities for specific patient endotypes.

Immunoglobulin E-Mediated Allergies in Lung-Transplanted Adults

BACKGROUND

Immunoglobulin E (IgE)-mediated allergy has repeatedly been reported after solid organ transplantation, apparently affecting approximately 10% of pediatric organ transplant recipients. Interestingly, type 1 allergy has not been described in transplanted adults, suggesting a particular propensity in childhood.

METHODS

The present cross-sectional study assessed the prevalence of type 1 allergy in 42 adult lung transplant recipients aged 25 to 50 years. Instruments included standardized interviews, skin prick tests, and serum IgE measurements.

RESULTS

Ten of 42 patients (23.8%) displayed elevated specific IgE levels or positive skin prick test results against one or more allergens. Five individuals (11.9%) additionally reported corresponding clinical symptoms of type 1 allergy. No statistically significant association of sensitization or allergy prevalence with patient age, kind of immunosuppressive therapy, and time since transplantation was found.

CONCLUSIONS

The phenomenon of transplantation-associated allergy is not age-restricted and thus should be assessed more thoroughly in all age groups.