Monogenic early-onset lymphoproliferation and autoimmunity: Natural history of STAT3 gain-of-function syndrome.

BACKGROUND: In 2014, germline signal transducer and activator of transcription (STAT) 3 gain-of-function (GOF) mutations were first described to cause a novel multisystem disease of early-onset lymphoproliferation and autoimmunity. OBJECTIVE: This pivotal cohort study defines the scope, natural history, treatment, and overall survival of a large global cohort of patients with pathogenic STAT3 GOF variants. METHODS: We identified 191 patients from 33 countries with 72 unique mutations. Inclusion criteria included symptoms of immune dysregulation and a biochemically confirmed germline heterozygous GOF variant in STAT3. RESULTS: Overall survival was 88%, median age at onset of symptoms was 2.3 years, and median age at diagnosis was 12 years. Immune dysregulatory features were present in all patients: lymphoproliferation was the most common manifestation (73%); increased frequencies of double-negative (CD4-CD8-) T cells were found in 83% of patients tested. Autoimmune cytopenias were the second most common clinical manifestation (67%), followed by growth delay, enteropathy, skin disease, pulmonary disease, endocrinopathy, arthritis, autoimmune hepatitis, neurologic disease, vasculopathy, renal disease, and malignancy. Infections were reported in 72% of the cohort. A cellular and humoral immunodeficiency was observed in 37% and 51% of patients, respectively. Clinical symptoms dramatically improved in patients treated with JAK inhibitors, while a variety of other immunomodulatory treatment modalities were less efficacious. Thus far, 23 patients have undergone bone marrow transplantation, with a 62% survival rate. CONCLUSION: STAT3 GOF patients present with a wide array of immune-mediated disease including lymphoproliferation, autoimmune cytopenias, and multisystem autoimmunity. Patient care tends to be siloed, without a clear treatment strategy. Thus, early identification and prompt treatment implementation are lifesaving for STAT3 GOF syndrome.

The impact of modernization on allergy and asthma development.

Background: In recent years, an increase of allergies and asthma has been observed throughout the world, more so in Western countries than in less developed ones. Although genetics may play a role in this increase, there are many other factors that may have contributed to the upsurge. Objective: The purpose of the present report was to review the many factors associated with modernization and lifestyle that may have contributed to the allergy and/or asthma epidemic, with a particular focus on those aspects that have particular relevance for the allergist/immunologist. Results: The marked rise in allergy and asthma has been significantly seen in more-developed countries, greater in urban than in rural areas, more pronounced in affluent than in poorer societies, and in individuals who have migrated from developing countries to industrialized countries. A widely accepted explanation for this rise is the "hygiene hypothesis," which postulates a critical dependence on microbial infection for maintenance of a healthy balanced immune system and that extremely clean external environments, often found in the developed world, can derail equilibrated immune development. With the control of infectious diseases, the immune system shifts from a balanced equilibrated immunologic structure to a more Th2 driven proinflammatory state often associated with IgE and eosinophil-related disorders. Conclusion: Modernization has been associated with increased development of allergies and asthma through a cleaner environment and more exposure to allergens and to multiple other contributory factors. The marked reduction in infectious diseases in recent decades permitted the immune system to switch from fighting infectious disease agents and parasites to reacting adversely (hypersensitivity) to benign environmental agents (allergens) and even to self-antigens (autoimmunity).

Identification of 22 novel BTK gene variants in B cell deficiency with hypogammaglobulinemia.

X-linked agammaglobulinemia (XLA) is an inborn error of immunity caused by pathogenic variants in the BTK gene, resulting in impaired B cell differentiation and maturation. Over 900 variants have already been described in this gene, however, new pathogenic variants continue to be identified. In this report, we describe 22 novel variants in BTK, associated with B cell deficiency with hypo- or agammaglobulinemia in male patients or in asymptomatic female carriers. Genetic data was correlated with BTK protein expression by flow cytometry, and clinical and family history to obtain a comprehensive assessment of the clinico-pathologic significance of these new variants in the BTK gene. For one novel missense variant, p.Cys502Tyr, site-directed mutagenesis was performed to determine the impact of the sequence change on protein expression and stability. Genetic data should be correlated with protein and/or clinical and immunological data, whenever possible, to determine the clinical significance of the gene sequence alteration.

NAPDH Oxidase-Specific Flow Cytometry Allows for Rapid Genetic Triage and Classification of Novel Variants in Chronic Granulomatous Disease.

PURPOSE: Chronic granulomatous disease (CGD) is an innate immune deficiency, primarily affecting the phagocytic compartment, and presenting with a diverse phenotypic spectrum ranging from severe childhood infections to monogenic inflammatory bowel disease. Dihydrorhodamine (DHR) flow cytometry is the standard diagnostic test for CGD, and correlates with NADPH oxidase activity. While there may be genotype correlation with the DHR flow pattern in some patients, in several others, there is no correlation. In such patients, assessment by flow cytometric evaluation of NADPH oxidase-specific (NOX) proteins provides a convenient and rapid means of genetic triage, though immunoblotting has long been used for this purpose. METHODS AND RESULTS: We describe the clinical utility of the NOX flow cytometry assay through assessment of X-linked and autosomal recessive CGD patients and their first-degree relatives. The assessment of specific NOX proteins was correlated with overall NADPH oxidase function (DHR flow), clinical phenotype and genotype. NOX-specific protein assessment is a valuable adjunct to DHR assessment and genotyping to classify and characterize CGD patients. CONCLUSIONS: The atypical clinical presentation of some CGD patients can make genotype-phenotype correlation with DHR flow data challenging. Genetic testing, while useful for confirmation of diagnosis, can take several weeks, and in some patients does not provide a conclusive answer. However, NADPH-oxidase-specific protein flow assessment offers a rapid alternative to identification of the underlying genetic defect in cellular subsets, and can be utilized as a reflex test to an abnormal DHR flow. Further, it can provide insight into correlation between oxidative burst relative to protein expression in granulocytes and monocytes.

Scoring systems for allergies and asthma in clinical research and practice.

Background: Scoring systems are increasingly being developed for various diseases, including asthma and allergic disorders, with the objective of improving the classification of disease severity and the assessment of efficacy of therapeutic modalities. Objective: This review provided concise summaries of published scoring systems used for allergic rhinitis, asthma, atopic dermatitis, urticaria, Stevens-Johnson syndrome/toxic epidermal necrolysis, eosinophilic esophagitis, and systemic allergic reactions (anaphylaxis). Methods: We searched the medical literature between 1985 and 2018 for published scoring systems that have been developed and used in clinical trials or in practice for assessment of asthma and a variety of allergic disorders. Results: The scoring systems for each of these diseases were briefly presented in the text in chronological order of publication, and selected information was presented in the tables for easy comparisons. For more details, the reader should refer to the original relevant publications. Conclusion: Such assessment methods are useful for sound designing of clinical trials, fair comparisons of findings of studies, and objective measurements of patients' progress in clinical practice. The choice of using one scoring system over another would depend on its proven degree of validity, the purpose, and applicability.

High-risk drug rashes.

OBJECTIVE: To provide a brief overview of the clinical presentation, common offending agents, management, prognosis, and mortality of 6 selected high-risk drug rashes, namely, Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, multiple drug hypersensitivity (MDH) syndrome, acute generalized exanthematous pustulosis (AGEP), and drug-induced bullous pemphigoid (DIBP). DATA SOURCES: A review of the published literature was performed with PubMed and supplemented with our clinical experience. STUDY SELECTIONS: The most recent clinically relevant studies and older seminal works were selected. RESULTS: Most of the published data on these uncommon rashes were based on small observational series or case reports. SJS and TEN have specific genotypes association with certain drugs, have high morbidity and mortality, and require aggressive management by a team of multiple specialists. DRESS syndrome is a severe, prolonged multiorgan reaction, yet it has a better prognosis than TEN. MDH is a syndrome of repeated reactions to unrelated drugs that often imposes diagnostic and management difficulties. AGEP consists of generalized sterile small pustules, usually mistaken for infection with subsequent inappropriate treatment. Bullous pemphigoid presents with tense pruritic bullae and characteristic linear basement membrane deposition of IgG and C3. DIBP has much better prognosis than the autoimmune variety. CONCLUSION: In such high-risk drug rashes, early recognition, immediate withdrawal of the suspected drug(s), prompt individualized management, and monitoring of vital organs function are mandatory for reducing morbidity and mortality. The lack of reliable tests for identification of the causative agent imposes difficulty, particularly in patients receiving multiple medications.

The dilemma of allergy to food additives.

OBJECTIVE: To provide a brief summary on food additives and to outline a practical approach for evaluating subjects suspected of having reactions to food additives. DATA SOURCES: Information was derived from selected reviews and original articles published in peer-reviewed journals, supplemented by the clinical experience of the authors. STUDY SELECTION: Priority was given to studies that used blinded, placebo controlled, oral challenges to confirm adverse reactions to food additives. In addition, selected, appropriately evaluated case reports were included. RESULTS: A large number of food additives are widely used in the food industry. Allergic reactions to additives seem to be rare but are very likely underdiagnosed, primarily due to a low index of suspicion. A wide variety of symptoms to food additives have been reported, but a cause-and-effect relationship has not been well documented in the majority of cases. CONCLUSION: Reactions to food additives should be suspected in patients who report symptoms related to multiple foods or to a certain food when commercially prepared but not when home made. It is also prudent to investigate food additives in subjects considered to have "idiopathic" reactions. Except for a limited number of natural additives, there is a small role for skin tests or in vitro testing. Oral challenge, in stages, with commonly used additives is the definitive procedure for detecting the offending agent. Once the specific additive is identified, management is strict avoidance, which can be difficult.

Pitfalls in anaphylaxis diagnosis and management at a university emergency department.

BACKGROUND: Some previous reports revealed suboptimal management of anaphylaxis (ANX) in the emergency department (ED). OBJECTIVE: To evaluate the recorded diagnosis and management of patients who presented with ANX at our university hospital ED and to assess how the management correlated with the severity of the case and the training level of the ED staff. METHODS: A descriptive study that involved reviewing the electronic medical records of patients who presented with ANX at the ED during a period of 4 years. RESULTS: When reviewing 1341 charts of potential cases, 60 met the criteria for ANX, but only 23% were correctly coded. Inaccurate coding was noted in 77%, mainly as an "allergic reaction." Systemic corticosteroids were administered in the ED to 85% of the patients and H1-antihistamines to 73%; only 20% received epinephrine. Ten patients required hospital admission, and, on discharge, only four patients (40%) were given epinephrine autoinjector prescriptions. Of the 50 who were discharged home, 48% were given epinephrine autoinjector prescriptions and 16% were given a referral for allergy evaluation. CONCLUSION: The observed low rates of appropriate diagnostic coding of ANX, of epinephrine administration, epinephrine autoinjector prescribing at discharge, and referral for allergy evaluation call for more education on these issues. Some of these pitfalls can be partly attributed to the setting in a university ED where health providers are usually busy in rendering urgent care.

International consensus guidelines for the diagnosis and management of food protein-induced enterocolitis syndrome: Executive summary-Workgroup Report of the Adverse Reactions to Foods Committee, American Academy of Allergy, Asthma & Immunology.

Food protein-induced enterocolitis (FPIES) is a non-IgE cell- mediated food allergy that can be severe and lead to shock. Despite the potential seriousness of reactions, awareness of FPIES is low; high-quality studies providing insight into the pathophysiology, diagnosis, and management are lacking; and clinical outcomes are poorly established. This consensus document is the result of work done by an international workgroup convened through the Adverse Reactions to Foods Committee of the American Academy of Allergy, Asthma & Immunology and the International FPIES Association advocacy group. These are the first international evidence-based guidelines to improve the diagnosis and management of patients with FPIES. Research on prevalence, pathophysiology, diagnostic markers, and future treatments is necessary to improve the care of patients with FPIES. These guidelines will be updated periodically as more evidence becomes available.

Skin rash in a 2-week-old infant.

We presented a case of a male infant with annular patchy rash on his torso since 2 weeks of age. This was initially diagnosed as tinea corporis but did not respond to oral antifungal treatment. Because of the appearance of the rash and a history of a certain disease in a maternal aunt, we suspected the most probable cause of the rash and the diagnosis was confirmed by laboratory testing. Furthermore, laboratory screening of the mother, who was asymptomatic, revealed that she was seropositive for the disease and was counseled on the importance of follow-up. The infant's rash gradually improved and completely disappeared, without any sequalae by 8 months of age.

Antiepilepsy drugs and the immune system.

OBJECTIVE: To alert physicians about the peculiar adverse effects of antiepilepsy drugs (AEDs) on the immune system. DATA SOURCES: PubMed literature during the past 25 years. STUDY SELECTIONS: Reports and review articles on the hypersensitivities of AEDs and their effect on immunity. RESULTS: AEDs have significant effects on the immune system in the form of hypersensitivity or immune suppression. IgE-mediated reactions can be urticaria, angioedema, bronchospasm, or anaphylaxis. Non-IgE-mediated reactions, more commonly associated with aromatic AEDs, can be in the form of nonspecific rashes or serious reactions, such as Stevens-Johnson syndrome, toxic epidermal necrolysis, drug rash with eosinophilia and systemic symptom syndrome, and acute generalized exanthematous pustulosis. Because of strong genetic predispositions for certain AEDs in causing severe reactions, HLA analysis before initiation of the drug is advised in certain populations. Immunoglobulin levels can be reduced to various degrees, particularly by carbamazepine, valproate, phenytoin, levetiracetam, zonisamide, and lamotrigine. Spontaneous return to normal levels can be rapid or take months to a few years, and intravenous immunoglobulin supplementation may be needed. Cellular effects can be in the form of cytopenias, inhibition of lymphocyte function, or cytokine dysregulation. CONCLUSION: When prescribing AEDs, physicians should pay special attention to their potential adverse effects on immunity or hypersensitivity, which can be severe and even fatal. For early recognition and intervention, monitoring such patients is necessary. The cornerstone of management is discontinued use of the suspected medication and avoidance of drugs of similar structure, particularly among members of the aromatic group.

Immediate hypersensitivity reactions to corticosteroids.

OBJECTIVE: To review the literature on immediate hypersensitivity reactions to corticosteroids and classify them according to manifestations, routes of exposure, causative preparations, diagnostic tests, and management. DATA SOURCES: PubMed search for English-language publications from January 1, 2004 through December 31, 2014 using search terms corticosteroid, glucocorticoid, or steroid combined with hypersensitivity, allergy, or anaphylaxis. STUDY SELECTION: Only reports of immediate hypersensitivity reactions that occurred sooner than 24 hours after administration of a corticosteroid were included. Excluded were reports on patients with delayed reactions, including contact dermatitis. RESULTS: Forty-eight articles fulfilled the criteria, reporting 120 reactions in 106 patients 2 to 90 years of age (55 male and 51 female). The most commonly reported manifestation was anaphylaxis in 60.8% (73 of 120) followed by urticaria and/or angioedema in 26.7%. Exposure to corticosteroid was through any route, with intravenous being the most common (44.2%, 53 of 120), followed by oral in 25.8% and intra-articular in 11.7%. Methylprednisolone was the most commonly implicated (40.8%) followed by prednisolone (20.0%). Some reacted to more than 1 preparation. Pharmacologically-inactive ingredients were implicated in 28.3%. Diagnosis was based primarily on medical history and in most cases was confirmed by challenge testing. Skin tests were positive in 74.1%. The vast majority of patients tolerated at least 1 alternative preparation, and very rarely desensitization was required. CONCLUSION: Corticosteroids seem to be rare causes of immediate hypersensitivity reactions but possibly are misdiagnosed or under-reported relative to their worldwide use. Physicians should be cognizant of this entity and identify safe alternative preparations.

Adverse reactions to infliximab and the outcome of desensitization.

BACKGROUND: Infliximab is a highly effective monoclonal antibody against tumor necrosis factor, which is a major inflammatory mediator in certain gastrointestinal, rheumatic, and skin diseases. In some patients, infliximab infusion causes systemic adverse reactions that often lead to discontinuation of therapy even in responsive patients. OBJECTIVE: To investigate the frequency and characteristics of adverse reactions to infliximab at the authors' institution and the outcome of their management, including desensitization. METHODS: This was a single-center retrospective study of patients who were treated with infliximab, primarily for inflammatory bowel disease, from January 1, 2000 to March 31, 2014. Data included age, sex, underlying disease, infliximab therapy duration before the first reaction, manifestation of reaction, onset, and management. RESULTS: There were 336 patients with inflammatory bowel disease who were treated with infliximab during the study period. Thirty patients (8.9%) developed a systemic adverse reaction to infliximab, which was discontinued in 15 patients (50%) and was continued in 3 patients after premedication and/or decreased infusion rate. Twelve patients (40%) underwent infliximab desensitization with gradually increasing doses starting at a dilution of 0.1 mg/mL to reach the full treatment dose over approximately 4 to 6 hours. It was successful in all 12 patients, who continued to receive up to 26 infliximab infusions, mostly without premedication. CONCLUSION: Infliximab can trigger systemic reactions that hinder its administration. The present desensitization protocol appears to be safe and effective and it can be considered in patients whose inflammatory bowel disease responds well to infliximab but who develop systemic adverse reactions.

A 17-month-old patient with severe anemia and respiratory distress.

Anemia can be caused by, or be associated with, many clinical conditions, including pulmonary diseases, some of which are rare and can be misdiagnosed. Nontraumatic pulmonary bleeding may be caused by a variety of conditions and results in anemia and pulmonary hemosiderosis, even when it is subtle. The differential diagnosis in such cases is extensive. We present the case of a diagnostic dilemma in a 17-month-old child hospitalized for severe anemia and respiratory distress in which the diagnosis was settled through an allergy/immunology consultation.

Food protein-induced enterocolitis syndrome to trivial oral mucosal contact.

Food protein-induced enterocolitis syndrome (FPIES) is a non-immunoglobulin E (IgE)-mediated gastrointestinal food hypersensitivity, mostly in infants. Patients usually present very ill and often misdiagnosed as acute gastroenteritis, sepsis, ileus, metabolic disorders, necrotizing enterocolitis, or severe gastroesophageal reflux disease. We present a case of an infant who had three acute FPIES episodes: the first was at 5 months of age after chewing on a cellophane wrapper, the second was due to sweet potato, and the third was due to rice cereal. It was realized that in the first episode, the wrapper was covering a rice cake. Evaluation at 7 months of age, while asymptomatic, showed normal complete blood count, low serum immunoglobulin E level, and negative allergy skin prick tests, indicating non-IgE sensitivity. Conclusion This case of FPIES has peculiar features in that it occurred in an exclusively breastfed infant and by non-ingestant oral contact with a trivial quantity of rice allergen.

History of food allergy and where we are today.

The food allergy (FA) entity went through a long difficult road which led to much delay in its recognition. After long periods of denial and misdiagnosis, it attained its current designation as food hypersensitivity or allergy. This review will briefly address the evolution of the FA entity from the early BC era until our 21st century and highlight the milestones in the main aspects of diagnosis, treatment, prevention, and research. A great recognition of the allergy specialty was gained by the discovery of its main mediator -immunoglobulin E in 1967 - which also helped in classifying FA into IgE-mediated (immediate-type) and non-IgE-mediated. The cause of the increasing prevalence during the past few decades may be attributed to an increased food consumption and the consequences of modern lifestyle (the hygiene hypothesis). In addition to a skillful medical history-taking, helpful tests have been developed involving the skin or blood. The scratch test was modified to the prick test and in certain instances prick-by-prick. The use of intradermal test has been markedly reduced. Blood testing began by measuring specific-IgE antibodies (sIgE) in the serum using the radioallergosorbent test which went through multiple modifications to avoid radioisotope material and increase the test's sensitivity. The test was advanced to measure sIgE to individual allergen components. Recently, cellular tests were developed in the form of basophil activation or mast cell activation. In most cases, FA needs verification by appropriately-designed challenge testing. Regarding treatment, strict avoidance remains the basic approach. Certain food-labeling regulations led to some improvement in the problem of hidden food allergens but more is desired. Recently some protocols for oral immunotherapy (OIT) showed reasonable safety and efficacy in preventing reactions to accidental exposures. The protocol for peanut has been approved in the United States and other foods are expected to follow. Epicutaneous immunotherapy showed higher safety and promising efficacy. Sublingual immunotherapy might follow as well. Studies on the use of certain biologicals, alone or in combination of OIT, showed promising findings. Very recently, omalizumab was approved in the United States for patients with multiple FA. A major change in the strategy of prevention is the benefit of introducing allergenic foods at an early age (4-6 months). Research on FA markedly flourished in recent decades with increasing numbers of investigators, funding, publications, and education. Despite the major strides, still more awaits exploration with expected better understanding and practice of FA.

World Allergy Organization (WAO) Diagnosis and Rationale for Action against Cow's Milk Allergy (DRACMA) guideline update - XII - Recommendations on milk formula supplements with and without probiotics for infants and toddlers with CMA.

Background: Cow's milk allergy (CMA) is the most common food allergy in infants. The replacement with specialized formulas is an established clinical approach to ensure adequate growth and minimize the risk of severe allergic reactions when breastfeeding is not possible. Still, given the availability of multiple options, such as extensively hydrolyzed cow's milk protein formula (eHF-CM), amino acid formula (AAF), hydrolyzed rice formula (HRF) and soy formulas (SF), there is some uncertainty as to the most suitable choice with respect to health outcomes. Furthermore, the addition of probiotics to a formula has been proposed as a potential approach to maximize benefit. Objective: These evidence-based guidelines from the World Allergy Organization (WAO) intend to support patients, clinicians, and others in decisions about the use of milk specialized formulas, with and without probiotics, for individuals with CMA. Methods: WAO formed a multidisciplinary guideline panel balanced to include the views of all stakeholders and to minimize potential biases from competing interests. The McMaster University GRADE Centre supported the guideline-development process, including updating or performing systematic evidence reviews. The panel prioritized clinical questions and outcomes according to their importance for clinicians and patients. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach was used, including GRADE Evidence-to-Decision frameworks, which were subject to review by stakeholders. Results: After reviewing the summarized evidence and thoroughly discussing the different management options, the WAO guideline panel suggests: a) using an extensively hydrolyzed (cow's milk) formula or a hydrolyzed rice formula as the first option for managing infants with immunoglobulin E (IgE) and non-IgE-mediated CMA who are not being breastfed. An amino-acid formula or a soy formula could be regarded as second and third options respectively; b) using either a formula without a probiotic or a casein-based extensively hydrolyzed formula containing Lacticaseibacillus rhamnosus GG (LGG) for infants with either IgE or non-IgE-mediated CMA.The issued recommendations are labeled as "conditional" following the GRADE approach due to the very low certainty about the health effects based on the available evidence. Conclusions: If breastfeeding is not available, clinicians, patients, and their family members might want to discuss all the potential desirable and undesirable consequences of each formula in infants with CMA, integrating them with the patients' and caregivers' values and preferences, local availability, and cost, before deciding on a treatment option. We also suggest what research is needed to determine with greater certainty which formulas are likely to be the most beneficial, cost-effective, and equitable.

Hypersensitivity to antihistamines.

Antihistamines are the cornerstone of allergy therapy and are not expected to cause hypersensitivity reactions. We describe two cases, one had urticaria to multiple anti-H1-preparations and the other had anaphylaxis to hydroxyzine. We also provide a review of the English literature on reported reactions regarding causative preparations and manifestations. The latter showed a wide range; most commonly urticaria/angioedema, contact dermatitis, anaphylaxis, and fixed drug eruption (FDE). Most reported cases were young to middle age adults, with apparent predilection to female subjects. The onset of reactions varied from a few minutes for anaphylaxis and urticaria/angioedema, several hours for maculopapular rashes, or longer for contact dermatitis and FDE. Almost all antihistamines have been reported as causing reactions; cetirizine was the most common oral preparation followed by its parent drug, hydroxyzine. Doxepin cream was the most commonly implicated topical preparation in causing contact dermatitis. A causal relationship is often difficult to recognize because the reaction may be similar to the disease being treated with that antihistamine preparation. Reactions to one preparation are likely to occur, but not always, to other members of the same class. Diagnosis is based on clinical suspicion and may be verified by challenge testing. Except for patch testing in contact dermatitis or fixed eruption, other tests have not shown optimal reliability. In most cases, challenge testing with multiple preparations would identify one or more preparations that can be tolerated. Although hypersensitivity to antihistamines seems to be very rare, awareness of the problem would reduce its misdiagnosis.