Desensitization Protocol Research Articles

Protocol for Successful Desensitization to Ivacaftor and Elexacaftor/Tezacaftor/Ivacaftor in a Delayed Hypersensitivity Reaction Confirmed by the Lymphocyte Transformation Test.

Protocol for Successful Desensitization to Ivacaftor and Elexacaftor/Tezacaftor/Ivacaftor in a Delayed Hypersensitivity Reaction Confirmed by the Lymphocyte Transformation Test.

Cystic fibrosis: desensitization in delayed hypersensitivity reactions to elexacaftor/tezacaftor/ivacaftor.

Background: Cystic fibrosis transmembrane conductance regulator modulators are the only available treatment for cystic fibrosis. Although elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA) is well-tolerated, rash has been reported as very frequent. In severe rashes, ELX/TEZ/IVA withdrawal is necessary, leading to clinical deterioration. The objective of the study is to increment the experience of ELX/TEZ/IVA desensitization. Methods: Adult patients who developed a delayed hypersensitivity rash to ELX/TEZ/IVA between December 2021 and February 2023 and required withdrawal due to ineffective rescue medication were included. Skins test for ELX/TEZ/IVA and IVA were conducted to establish hypersensitivity mechanism. Balijepally ELX/TEZ/IVA desensitization protocol was selected. In cases where desensitization had to be discontinued due to rash, an extended desensitization was proposed. Clinical and health-related quality of life parameters were collected before ELX/TEZ/IVA and after desensitization. Results: 162 patients (81 women, 31.2 [23.8-42.5] years) started ELX/TEZ/IVA, developing rash 12 of them (7.4%, six women). Six patients (five women) required stopping ELX/TEZ/IVA and were selected for desensitization. Skin tests indicated delayed type-IV hypersensitivity in one patient. Two patients presented adequate tolerance to desensitization; while, four patients developed rash. Three of these patients, successfully concluded extended desensitization (one patient declined participation). No significant clinical deterioration or quality of life worsening was observed during desensitization; in fact, there was an improvement in practically all mesured parameters. All five patients who resumed ELX/TEZ/IVA are currently receiving therapy with good tolerance. Conclusion: Desensitization to ELX/TEZ/IVA could be a successful and safe strategy for reintroducing this essential treatment in cases of a delayed hypersensitivity rash.

519P The efficacy of oxaliplatin desensitisation protocol in patients with GI malignancies

519P The efficacy of oxaliplatin desensitisation protocol in patients with GI malignancies

#1016 Kidney transplantation in highly sensitized patients with preformed donor-specific antibodies through personalized delisting strategies

Abstract Background and Aims This study explores a personalized delisting strategy enabling kidney transplantation in highly sensitized patients with preformed donor-specific anti-HLA antibodies (DSA) trying to minimize the risk of antibody-mediated rejection (ABMR). Method Retrospective single-centre analysis of 50 kidney transplant recipients with preformed DSA (preDSA) after employing a delisting strategy to enhance their access to transplantation, and without received a pre-transplant or immediate post-transplant desensitization protocol. The delisting approach focused on allowing less deleterious antibodies according to their mean fluorescence intensity (MFI), anti-HLA class and C1q study results. The strategy consisted on eliminating as prohibited HLA antigens those recognized by antibodies with the lowest MFI in the following order: 1st- MFI < 5000; 2nd- MFI < 10000; 3rd-Any MFI. Additionally, delisting prioritized a single locus in the following order: 1st- one of the HLA class I loci (A, B, or Cw); 2nd- the rest of the class I loci; 3rd- HLA-DP, followed by DR. C1q studies were performed before delisting and transplantation was contraindicated in the presence of DSA detected in the C1q assay. Two comparative cohorts included 50 sensitized recipients without pre-transplant DSA (SwoDSA) and 50 non-sensitized recipients (NS). Results The delisting strategy allowed transplantation with preformed DSA and demonstrated comparable rejection rates to SwoDSA and NS groups (16%, 14% and 8%, respectively; log-rank = 0.28). However, the occurrence of acute ABMR was 12% in the preDSA group, significantly higher than in SwoDSA (1%) and NS (0%) (log-rank = 0.0093). The immunological risk assumed in delisting correlated with ABMR incidence (patients with ABMR had significantly higher sum MFI [mean ± SD: 9301 ± 6340 vs 4492 ± 5641; p = 0.049]), emphasizing the importance of tailored strategies. DSA persistence after transplantation correlated with higher MFI and increased ABMR risk. Of note, 16% of preDSA patients developed de novo DSA versus only the 4% of SwoDSA and 0% of NS patients (p = 0.004). After a mean follow-up of 3.1 ± 2.1 years, the 1-, 3- and 5-year death-censored allograft survival rates were 100%, 90% and 78%, respectively, in the preDSA group; 98%, 84% and 84% in the SwoDSA group and 100% in NS group (log-rank = 0.02). Conclusion The present study demonstrates the feasibility and acceptable outcomes of kidney transplantation in highly sensitized patients with preformed DSA through a personalized delisting strategy without using desensitization protocols.

Abstract PO3-12-08: Hypersensitivity reactions to paclitaxel and carboplatin in breast cancer: safety and effectiveness of desensitization

Abstract Introduction. Taxanes and platinums are first line treatment of breast cancer for early stages and metastatic disease and constitute the most commonly implicated chemotherapeutics in hypersensitivity reactions.1 Clinical manifestations range from mild skin reactions to anaphylaxis.2 Hypersensitivity reactions (HSR) to paclitaxel and carboplatin occur in a significant percentage of patients, with estimates of 30% and 40% respectively,3,4,5 leading to discontinuation of treatment.6 Using alternative drugs can be poorly tolerated or much less effective, entailing to high morbidity and mortality.7 Desensitization is the procedure performed to achieve a tolerance to the drug to which a HSR previously occurred, in order to maintain first-line treatment.8 The evaluation of the oncological response remains in the importance of assessing the shrinkage of the tumor and the time of progression of the disease.9 Objective: To describe the hypersensitivity reactions to paclitaxel and carboplatin, and the safety and effectiveness of desensitization protocols after anaphylaxis in patients with breast cancer. Materials and Methods: Original, retrospective, descriptive, and analytical study, approved by the Bioethics and Research Committee ON23-00016 code, included patients >18 years with breast cancer who developed a hypersensitivity reaction to first-line chemotherapy and performed a 3-bag-12-step desensitization according to the Brigham and Women's Hospital, Dana Farber Institute, Boston protocol. Results: Forty-five desensitization to paclitaxel or carboplatin were performed in 8 women with breast cancer, mean age 38.6 years. 6 patients developed HSR to paclitaxel, 83% of which were in the first application, and 2 patients developed HSR to carboplatin after several cycles. The most predominant symptom of HSR was cutaneous in 87% of the cases, and all patients presented cardiovascular HSR to paclitaxel. No patients developed HSR during desensitization. Currently, only 1 patient developed disease progression, while the rest presented a complete response to treatment. Discussion. HSR to paclitaxel appear in the 1-2 cycle,10 while to platinums after various exposures ( >6 cycles) similar to our study.3,4 The symptoms associated with paclitaxel are cardiovascular10,11 while urticaria is the most frequent in carboplatin.3,11 The desensitization protocol implemented did not develop HSR in any of the patients. Neoadjuvant chemotherapy in breast cancer has been shown to yield better disease-free interval results alongside improved pathological response.12 Conclusions. The program implemented in our hospital's chemotherapy desensitization clinic, replicating the model of the Dana-Farber Cancer Institute, Brigham, and Women's Hospital in Boston, has enabled cancer patients to continue with first-line treatment, thus improving their prognosis and quality of life, opening new areas of opportunity in the multidisciplinary management of these patients to improve overall survival. Characteristics of patients with hypersensitivity reactions HSR: hypersensitivity reactions ND: No data m: months yrs.: years Desensitization protocol to Paclitaxel IV (300 mg) IV: intravenous mg: milligram mL: milliliter h: hour Citation Format: Rosalaura V. Villarreal-González, Oscar Vidal-Gutiérrez, Javier A. Martínez-Moyano, Marianela Madrazo-Morales, Kathia S. Sáenz-Cantú, Patricia Rodríguez-Niño. Hypersensitivity reactions to paclitaxel and carboplatin in breast cancer: safety and effectiveness of desensitization [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO3-12-08.

Eye Movement Desensitization Protocol for Urge to Reduce Scratching Behaviour in Patients with Prurigo Nodularis: A Pilot Study.

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Successful rapid liposomal amphotericin B desensitization in pediatric case series.

Background: Liposomal amphotericin B (LAMB) is a crucial agent in the treatment of invasive fungal diseases caused by a wide variety of yeasts and molds. In the presence of an infection caused by a fungal agent resistant to alternative antifungal drugs, desensitization may be the only option to continue treatment. However, there is insufficient information and consensus with regard to amphotericin B desensitization protocols in the pediatric age group. Objective: We present our experience with five cases of patients in whom successful desensitization protocols were applied with LAMB, along with a review of the literature on pediatric cases. We also provide a sample desensitization protocol that we successfully applied. Methods: Pediatric patients who continued their treatment with the successful rapid desensitization protocol conducted at the Paediatric Allergy and Immunology Clinic of the Ministry of Health Ankara City Hospital between September 2019 and September 2023 were examined. Desensitization protocols were applied based on Castells' desensitization protocol. Results: Five patients ages between 5 and 12 years were referred to us due to the development of anaphylaxis during their treatment with LAMB. Anaphylaxis is diagnosed clinically, according to the European Academy of Allergy and Clinical Immunology guidelines: anaphylaxis (2021 update). A 16-step desensitization protocol was prepared by using LAMB solutions at four different dilutions (0.001, 0.01, 0.1, and 1 mg/mL). Each solution consisted of four steps, with a 15-minute infusion for each step. The patients were premedicated with 1 mg/kg/dose methylprednisolone and an antihistamine. Conclusion: The data we present on the successful application of a sample protocol to five cases, particularly in a pediatric setting, are noteworthy valuable contributions to the field, which demonstrates the feasibility and success of rapid desensitization with LAMB in pediatric patients. This can provide important insights and potentially serve as a reference for medical professionals working with similar cases in the future.

Pneumocystis jirovecii Pneumonia in a Liver Transplant Recipient With an Adverse Reaction to Trimethoprim/Sulfamethoxazole Treated With a Sulfonamide Desensitization Protocol: Case Report

Pneumocystis jirovecii pneumonia (PJP) is an opportunistic fungal infection that, in immunocompromised patients, can progress to respiratory failure and death. Since trimethoprim/sulfamethoxazole (TMP/SMX) chemoprophylaxis has become a standard management, the prognosis has improved. However, there are patients with a history of TMP/SMX intolerance who cannot receive chemoprophylaxis. We report on a 53-year-old male liver recipient treated with a standard triple immunosuppressive regimen in whom TMP/SMX was waived because of a history of allergy manifested as a generalized rash with edema more than 30 years ago. At transplantation, the immunologic risk was assessed as low, and liver graft function was normal. In the third month after engraftment, he developed dyspnea at rest required constant passive oxygen therapy. Ceftriaxone, azithromycin, and clindamycin were implemented. Mycophenolate acid was stopped, and tacrolimus was reduced. High-resolution computed tomography revealed interstitial pneumonia. Pneumocystis jirovecii pneumoniae was diagnosed from bronchoalveolar lavage. Instead of TMP/SMX, pentamidine and caspofungin were also used for PJP, with no improvement. After 3 weeks, the patient deteriorated. Because of his life-threatening condition, TMP/SMX was introduced in the sulfonamide desensitization protocol, including hydrocortisone and clemastinum. Within 4 days, the patient stabilized with no signs of TMP/SMX intolerance. Pneumonia subsided within a month, and TMP/SMX was prescribed lifelong. Prophylaxis for PJP with TMP/SMX still remains an important issue in transplant recipients. Adverse reaction to TMP/SMX in the past is not always a contraindication to reintroducing prophylaxis. The decision of prophylaxis avoidance should be analyzed carefully; in uncertain cases, a sulfonamide desensitization protocol should be considered.

Desensitization of Highly Immunized Kidney Transplant Recipients Awaiting Transplantation—Polish Single-Center Experience

IntroductionThe increasing number of highly immunized patients waiting for kidney transplantation is a significant problem in Europe as the proportion of such patients has doubled in the last decade. Transplantation in this group is enabled by desensitization methods, i.e., intravenous pharmacotherapy with human immunoglobulin (IVIG), anti-CD20 monoclonal antibody (rituximab), and plasma exchange. The objective was to evaluate the efficacy and safety of this protocol. Material and MethodsThe inclusion criteria: presence of established anti-HLA antibodies with complement-binding capacity, i.e., anti-HLAC1q+ (>MFI 15,000 for the most common antigens), no renal transplantation within 1 year after activation on the waiting list. Thirteen patients were selected for the procedure. IVIG was administered twice (2 g/kg-maximum 140 g/dose). Between IVIG doses, patients received rituximab (375 mg/m2). Anti-HLA was tested after 1 and 2 months after completion of the procedure. ResultsAll patients have completed the protocol. No significant changes after desensitization in the amount/profile of alloantibodies were observed. However, with negative vCM for HLA-A/B/DR (no DSA against the reported donor) and negative CM-CDC, according to the allocation system, patients were given priority on the recipient list. Seven out of 13 patients received a transplant within 12 months after treatment (mean 11.5 weeks). Renal graft function was good (mean creatinine level after 1 month: 1.5 mg/dL). No incidents of acute rejection were reported. The most common complications were infections (especially pneumonia). ConclusionThe desensitization protocol (IVIG + rituximab) allows highly immunized patients to undergo organ transplantation. In short-term analysis, no acute rejection was observed, graft function was satisfactory. Desensitization was associated with an increased risk of infection.

Balancing Benefits and Risks: A Literature Review on Hypersensitivity Reactions to Human G-CSF (Granulocyte Colony-Stimulating Factor).

Human granulocyte colony-stimulating factor (G-CSF) is a granulopoietic growth factor used in the treatment of neutropenia following chemotherapy, myeloablative treatment, or healthy donors preparing for allogeneic transplantation. Few hypersensitivity reactions (HRs) have been reported, and its true prevalence is unknown. We aimed to systematically characterize G-CSF-induced HRs while including a comprehensive list of adverse reactions. We reviewed articles published before January 2024 by searching in the PubMed, Embase, Cochrane Library, and Web of Science databases using a combination of the keywords listed, selected the ones needed, and extracted relevant data. The search resulted in 68 entries, 17 relevant to our study and 7 others found from manually searching bibliographic sources. A total of 40 cases of G-CSF-induced HR were described and classified as immediate (29) or delayed (11). Immediate ones were mostly caused by filgrastim (13 minimum), with at least 9 being grade 5 on the WAO anaphylaxis scale. Delayed reactions were mostly maculopapular exanthemas and allowed for the continuation of G-CSF. Reactions after first exposure frequently appeared and were present in at least 11 of the 40 cases. Only five desensitization protocols have been found concerning the topic at hand in the analyzed data. We believe this study brings to light the research interest in this topic that could benefit from further exploration, and propose regular updating to include the most recently published evidence.

Aspirin hypersensitivity: a practical guide for cardiologists.

Aspirin has been known for a long time and currently stays as a cornerstone of antithrombotic therapy in cardiovascular disease. In patients with either acute or chronic coronary syndromes undergoing percutaneous coronary intervention aspirin is mandatory in a dual antiplatelet therapy regimen for prevention of stent thrombosis and/or new ischaemic events. Aspirin is also currently a first-option antithrombotic therapy after an aortic prosthetic valve replacement and is occasionally required in addition to oral anticoagulants after implantation of a mechanical valve. Presumed or demonstrated aspirin hypersensitivity is a main clinical problem, limiting the use of a life-saving medication. In the general population, aspirin hypersensitivity has a prevalence of 0.6%-2.5% and has a plethora of clinical presentations, ranging from aspirin-exacerbated respiratory disease to anaphylaxis. Although infrequent, when encountered in clinical practice aspirin hypersensitivity poses for cardiologists a clinical dilemma, which should never be trivialized, avoiding-as much as possible-omission of the drug. We here review the epidemiology of aspirin hypersensitivity, provide an outline of pathophysiological mechanisms and clinical presentations, and review management options, starting from a characterization of true aspirin allergy-in contrast to intolerance-to suggestion of desensitization protocols.

Rates of paclitaxel hypersensitivity reactions using a modified Markman’s infusion protocol as primary prophylaxis

PurposeMarkman’s desensitisation protocol allows successful retreatment of patients who have had significant paclitaxel hypersensitivity reactions. We aimed to reduce the risk and severity of paclitaxel hypersensitivity reactions by introducing this protocol as primary prophylaxis.MethodsWe evaluated all patients with a gynaecological malignancy receiving paclitaxel before (December 2018 to September 2019) and after (October 2019 to July 2020) the implementation of a modified Markman’s desensitisation protocol. The pre-implementation group received paclitaxel over a gradually up-titrated rate from 60 to 180 ml/h. The post-implementation group received paclitaxel via 3 fixed-dose infusion bags in the first 2 cycles. Rates and severity of paclitaxel hypersensitivity reactions were compared.ResultsA total of 426 paclitaxel infusions were administered to 78 patients. The median age was 64 years (range 34–81), and the most common diagnosis was ovarian, fallopian tube and primary peritoneal cancer (67%, n = 52/78). Paclitaxel hypersensitivity reaction rates were similar in the pre-implementation (8%, n = 16/195) and post-implementation groups (9%, n = 20/231; p = 0.87). Most paclitaxel hypersensitivity reactions occurred within 30 min (pre- vs. post-implementation, 88% [n = 14/16] vs. 75% [n = 15/20]; p = 0.45) and were grade 2 in severity (pre- vs. post-implementation, 81% [n = 13/16] vs. 75% [n = 15/20]; p = 0.37). There was one grade 3 paclitaxel hypersensitivity reaction in the pre-implementation group. All patients were successfully rechallenged in the post-implementation group compared to 81% (n = 13/16) in the pre-implementation group (p = 0.43).ConclusionThe modified Markman’s desensitisation protocol as primary prophylaxis did not reduce the rate or severity of paclitaxel hypersensitivity reactions, although all patients could be successfully rechallenged.

Perioperative Management of 6-way Simultaneous Paired Kidney Exchange Transplantation – An Observational Study

Objective: The presence of donor-specific antigens (human leukocyte antigen [HLA] incompatibility) leads to positive T-cell or B-cell crossmatch. Kidney transplant after desensitization protocols not only poses a financial burden on the patients but also there is an increased rate of infections and graft rejection. Paired kidney exchange (PKE) is cost-effective and offers better postoperative graft outcome. Methods: We included six pairs of kidney transplant donors and recipients for 6-way simultaneous PKE transplantation. These patients were ABO incompatible or HLA incompatible or both. Results: All patients underwent transplant in a single day without any perioperative surgical and anesthesia complications except for the need of mechanical ventilation in one patient in the postoperative care unit. The graft function was excellent in all recipients. Conclusion: This is the first 6-way simultaneous kidney exchange transplantation in the northwestern region of India. The inclusion of multiple donors and recipients for a paired exchange kidney transplant, although challenging, increases the donor pool and decreases the waiting time and financial constraints.

Current state and advances in desensitization for peanut allergy in pediatric age.

Peanut allergy affects about 1%-3% of the pediatric population in the world, with an important increase in the last decades. Nowadays, international guidelines recommend the early introduction of peanuts in the infant diet, with poor information about the quantity and the frequency of the intake. Allergen immunotherapy may represent the only therapeutic strategy able to modify the natural history of peanut allergy. In particular, oral immunotherapy showed the most promising results in terms of efficacy, but with significant rates of adverse reactions, mostly gastrointestinal. In 2020, the Food and Drug Administration and the European Medicines Agency approved Palforzia®, an oral drug for patients aged 4-17 years. Several studies are ongoing to improve the tolerability of oral immunotherapy and standardize the desensitization protocols. Sublingual immunotherapy permits to offer much lower doses than oral immunotherapy, but fewer adverse events are shown. Subcutaneous immunotherapy is associated with the greatest systemic adverse effects. Epicutaneous immunotherapy, for which Viaskin® patch was approved, has the highest safety profile. Innovative studies are evaluating the use of biological drugs, such as omalizumab or dupilumab, and probiotics, such as Lactobacillus rhamnosus, in monotherapy or associated with oral immunotherapy. Therapy for peanut allergy is constantly evolving, and new perspectives are ongoing to develop.

A 14-step desensitization protocol for sebelipase alfa hypersensitivity in a patient with Wolman disease and secondary hemophagocytic lymphohistiocytosis.

A 14-step desensitization protocol for sebelipase alfa hypersensitivity in a patient with Wolman disease and secondary hemophagocytic lymphohistiocytosis.

(1276) - Combined Heart and Lung Transplantation Across Preformed Donor-Specific Antibodies Using a Peritransplant Desensitization Protocol

(1276) - Combined Heart and Lung Transplantation Across Preformed Donor-Specific Antibodies Using a Peritransplant Desensitization Protocol

Prevention of allergic reactions during oxaliplatin desensitization through inhibition of Bruton tyrosine kinase

BackgroundAcute infusion reactions to oxaliplatin, a chemotherapeutic used to treat gastrointestinal cancers, are observed in about 20% of patients. Rapid drug desensitization (RDD) protocols often allow the continuation of oxaliplatin in patients with no alternative options. Break-through symptoms including anaphylaxis can still occur during RDDs. ObjectiveTo evaluate if pretreatment with acalabrutinib, a Bruton’s tyrosine kinase inhibitor, can prevent anaphylaxis during a RDD in a patient sensitized to oxaliplatin. MethodsA 52-year-old male with locally advanced gastric carcinoma developed anaphylaxis during his 5th cycle of oxaliplatin. As he required 6 additional cycles to complete his curative-intent treatment regimen, he underwent RDD to oxaliplatin but still developed severe acute reactions. The risks and benefits of adding acalabrutinib prior to and during a RDD, were reviewed and he elected to proceed. ResultsWith acalabrutinib taken prior to and during the RDD, the patient was able to tolerate oxaliplatin RDDs without complication. Consistent with its mechanism of action, acalabrutinib completely blocked the patient’s positive skin prick response to oxaliplatin. Acalabrutinib did not alter the percentage of circulating basophils (1.24% versus 0.98%) prior to the RDD but protected from basopenia (0.74% versus 0.09%) after the RDD. Acalabrutinib was associated with a drastic reduction in the ability of basophils to upregulate CD63 in vitro following incubation with oxaliplatin (0.11% versus 2.38%) or polyclonal anti-human IgE antibody (0.08% versus 44.2%). ConclusionsFive doses of acalabrutinib 100mg orally twice daily starting the evening 2 days before and continuing through a RDD allowed a sensitized patient to successfully and safely receive oxaliplatin.

O204: The influence of HLA matching on graft survival in lung transplant recipients is indication specific: An UNOS database analysis

Abstract Background and aims The importance of human leukocyte antigen (HLA) matching in lung transplantation remains unclear, and the influence of indication in HLA compatibility is unknown. This study aimed to determine the relationship between HLA matching and lung graft survival using a large-scale multi-center database (UNOS/OPTN) and multivariate logistic analysis. The secondary aim was to determine whether this relationship was influenced by transplant indication. Methods This retrospective observational analysis was performed using 26,312 lung transplant recipients from the UNOS/OPTN database. Patients were divided into two groups based on number of HLA mismatches (0-3 mismatches vs 4-6 mismatches) and then subcategorized by indication. Risk-adjusted outcomes were assessed by multivariate Cox analysis adjusting for donor and recipient characteristics and visualized using Kaplan-Meier survival curves. Results Increased HLA mismatch was associated with reduced allograft survival. Adjusted models found that the total HLA mismatch >3 increased the mortality hazard at 15 years (HR 1·05, p <0·05) and 20 years (HR 1·05, p<0·01). Pulmonary hypertension was the only indication with a statistically significant association between HLA mismatch and graft survival. Allografts in patients with 0-3 mismatches survived for 401 days longer than those with 4-6 mismatches (p=0·02). Conclusion Increased HLA mismatch reduced graft survival. When stratified by indication, this association was preserved exclusively in pulmonary hypertension. This finding is of potential clinical relevance to the management of this subsection of lung transplant recipients, impacting organ allocation, transplant surveillance and use of desensitisation and immunosuppression protocols.

Drug-Induced Anaphylaxis in Children.

Drug-induced anaphylaxis in children is less common than in adults and primarily involves beta-lactams and nonsteroidal anti-inflammatory drugs. Epidemiological studies show variable prevalence, influenced by age, gender, and atopic diseases. The pathophysiology includes IgE-mediated reactions and non-IgE mechanisms, like cytokine release reactions. We address drug-induced anaphylaxis in children, focusing on antibiotics, nonsteroidal anti-inflammatory drugs, neuromuscular blocking agents, and monoclonal antibodies. Diagnosis combines clinical criteria with in vitro, in vivo, and drug provocation tests. The immediate management of acute anaphylaxis primarily involves the use of adrenaline, coupled with long-term strategies, such as allergen avoidance and patient education. Desensitization protocols are crucial for children allergic to essential medications, particularly antibiotics and chemotherapy agents.

Infliximab desensitization in patients with inflammatory bowel diseases: a safe therapeutic alternative

Background Hypersensitivity reactions (HSR) to the administration of infliximab (IFX) in Inflammatory Bowel Diseases (IBD) patients are not rare and usually lead to drug discontinuation. We report data on safety and effectiveness of desensitization to IFX in patients with previous HSR. Methods We conducted a retrospective monocentric observational study. Patients for whom a desensitization protocol to IFX was realized after a previous HSR were included. Anti-drug antibodies (ADA) and IFX trough levels at both inclusion and six months after desensitization were collected. Clinical outcomes, including recurrence of HSR were evaluated. Results From 2005 to 2020, 27 patients (Crohn’s Disease: 26 (96%) were included). Desensitization after HSR was performed after a median time of 10.4 months (2.9-33.1). Nineteen (70%) patients received immunosuppressants at time of desensitization. Eight (30%) patients presented HSR at first (n = 2), second (n = 4) or third (n = 2) IFX perfusion after desensitization. None led to intensive care unit transfer or death. Thirteen (48%) had clinical response at 6 months and 8 (29%) were still under IFX treatment two years after desensitization. IFX trough levels and ADA were available for 14 patients at time of desensitization. Most patients (12 out of 14) had ADA at a high level. At 6 months, among the 7 patients with long term response to IFX, 4 presented a decrease of ADA titers and 2 had a significant trough level of IFX. Conclusion IFX desensitization in patients with IBD is a safe therapeutic alternative and represents a potential option for patients refractory to multiple biologics. What is already known? Hypersensitivity reactions to the administration of infliximab is frequent. Occurrence of hypersensitivity reaction, either immediate or delayed, usually leads to permanent drug discontinuation. What is new here? Infliximab desensitization is well tolerated with no hypersensitivity reaction recurrence in 70% of patients. Clinical success at 6 months was of 48% and around a third of patients remained under infliximab therapy two years after desensitization. Antidrug antibodies decreased and infliximab trough levels increased in these patients showing the impact of desensitization on immunogenicity. How can this study help patient care? Infliximab desensitization represents a potential option for patients refractory to multiple biologics who presented hypersensitivity reaction to the drug.