Genomic Testing Identifies Monogenic Causes in Patients with Very Early-Onset Inflammatory Bowel Disease: A Multi-center Survey in an Iranian Cohort

Patients with very early-onset inflammatory bowel disease (VEO-IBD) may present because of underlying monogenic inborn errors of immunity (IEI). Strong differences have been observed in the causes of monogenic IBD among ethnic populations. This multi-center study was carried out on 16 Iranian patients with VEO-IBD. We reviewed clinical and basic immunologic evaluation including flow cytometry and immunoglobulin levels. All patients underwent clinical whole exome sequencing (WES). Sixteen patients (8 females and 8 males) with a median age of 43.5 months were enrolled. The median age at the onset of symptoms was 4 months. Most patients (12, 75%) had consanguineous parents. Chronic non-bloody diarrhea (13, 81.3%) and perianal diseases including perianal abscess (6, 37.5%), anal fissure (6, 37.5%), or anal fistula (2, 12.5%) were the most common manifestations. WES identified a spectrum of genetic variants in 13 patients (81.3%): IL10RB (6, 37.5%), MVK (3, 18.8%), and CASP8, SLC35C1, G6PC3, and IKBKB in one patient, respectively. In 3 patients (18.7%) no variant was identified. Flow cytometry identified a spectrum of abnormalities that helped to assess the evidence of genetic diagnosis. At the end of the survey, 3 (18.8%) patients were deceased. This high rate of monogenic defects with a broad spectrum of genes reiterates the importance of investigating IEI in patients with infantile-onset IBD.

The Radiological Manifestations of Phagocytic Primary Immunodeficiencies in Children

Primary immunodeficiencies are a diverse group of rare genetic disorders, among which phagocytic dysfunction impairs neutrophil function in a wide range of inherited disorders. Due to the heterogeneity of the disorders a multidisciplinary approach is often required for early diagnosis and initiation of appropriate treatments. The aim of this study was to evaluate the imaging findings in children admitted with phagocytic primary immunodeficiencies. Thirty-five children who fulfilled the inclusion criteria for phagocytic dysfunction were enrolled in this study. The patients were under close observation and monitoring from January 2011 until data locking in December 2017. The diagnosis of phagocytic immunodeficiency was confirmed by the patient's clinical course, presentation features, and laboratory data.  Among the 35 patients studied, the most frequent condition was chronic granulomatous disease (CGD) (23 patients), followed by different types of neutropenia (8 patients) and Job's syndrome (4 patients). Mediastinal and hilar lymphadenopathies and consolidation were the most frequent presentations. There was a significant relationship between mediastinal/hilar lymphadenopathies and fungal infections. A meaningful relationship was also found between pulmonary nodules without halo signs in patients with concomitant tuberculosis and fungal infections. A significant correlation was found between CGD, pulmonary fibrotic changes, and mediastinal lymphadenopathies. The most frequent radiological manifestations in children included mediastinal and hilar consolidations. Physicians' awareness of the radiological and clinical manifestations of these inherited diseases may be helpful in the early diagnosis and timely initiation of specific prophylaxis measures to prevent infections and also to initiate hematopoietic stem cell transplantation as the curative management modality.

JAGN1 mutation with distinct clinical features; two case reports and literature review

Jagunal homolog 1 (JAGN1) has been recognized as an essential protein in neutrophil function. The mutated JAGN1 is responsible for immunodeficiency related to innate and humoral defense mechanisms. This deficiency impairs neutrophil development and function, leading to recurrent infections and facial dysmorphism as phenotypic consequences of severe congenital neutropenia (SCN). We report two siblings having the reported JAGN1 mutation with different clinical manifestations. Recurrent abscess formation unresponsive to antibiotic therapy, a history of delayed umbilical separation, frequent bacterial or fungal infection, dysmorphic face, failure to thrive, and other coexisting organ abnormalities should prompt physicians to syndromic immunodeficiencies involving neutrophils. Genetic investigations to elucidate the responsible mutation is critical as clinical management varies. Once the diagnosis is confirmed, a multi-disciplinary team should perform further workups to investigate other coexisting malformations and neurodevelopmental evaluation.

Autoimmune versus Non-autoimmune Cutaneous Features in Monogenic Patients with Inborn Errors of Immunity

Cutaneous manifestations are one of the most common presentations among patients with inborn errors of immunity (IEI). These skin manifestations are often among the first presenting features in the majority of patients preceding the IEI diagnosis. We studied 521 available monogenic patients with IEI listed in the Iranian IEI registry up to November 2022. We extracted each patient's demographic information, detailed clinical history of cutaneous manifestations, and immunologic evaluations. The patients were then categorized and compared based on their phenotypical classifications provided by the International Union of Immunological Societies. Most patients were categorized into syndromic combined immunodeficiency (25.1%), non-syndromic combined immunodeficiency (24.4%), predominantly antibody deficiency (20.7%), and diseases of immune dysregulation (20.5%). In total, 227 patients developed skin manifestations at a median (IQR) age of 2.0 (0.5-5.2) years; a total of 66 (40.7%) of these patients initially presented with these manifestations. Patients with cutaneous involvement were generally older at the time of diagnosis [5.0 (1.6-8.0) vs. 3.0 (1.0-7.0) years; p = 0.022]. Consanguinity was more common among patients who developed skin disorders (81.4% vs. 65.2%, p < 0.001). The overall skin infection rate and the type of dominant pathogens were significantly different among the IEI patients in different phenotypical classifications (p < 0.001). Atopic presentation, including urticaria, was highly prevalent among patients with congenital defects of phagocytes (p = 0.020). The frequency of eczema was also significantly higher among cases with both syndromic and non-syndromic combined immunodeficiency (p = 0.009). In contrast, autoimmune cutaneous manifestations, including alopecia and psoriasis, were most common in patients with immune dysregulation (p = 0.001) and defects in intrinsic or innate immunity (p = 0.031), respectively. The presence of autoimmune cutaneous complications significantly improved the survival rate of IEI patients (p = 0.21). In conclusion, cutaneous manifestations were observed in nearly 44% of Iranian patients with monogenic IEI. A considerable number of patients with cutaneous involvements developed these disorders as their first manifestation of the disease, which was particularly noticeable in patients with non-syndromic combined immunodeficiency and phagocytic defects. The neglected skin disorders in IEI patients might delay diagnosis, which is generally established within a 3-year interval from the development of skin-related problems. Cutaneous disorders, especially autoimmune features, might indicate a mild prognosis in IEI patients.

Inflammatory Responses of Women with Polycystic Ovary Syndrome in Vitro Differ from Healthy Women

Polycystic ovary syndrome is a low-grade inflammatory state with increased serum levels of TNF-α. The present study has compared the inflammatory responses to breast cancer cell lines in women with PCOS with healthy women. Peripheral blood mononuclear cells (PBMCs) isolated from 50 women with PCOS and 50 healthy controls were cultured in the trans-well co-culture system. These cells were stimulated with two distinct breast cancer cell lines. The proliferation of PBMCs, CD3+CD8+T cell percentages, and tumor necrosis factor-alpha (TNF-α) concentration were evaluated after 48 and 72 hours of incubation. TNF-α concentration and the proliferation rate of PBMCs after 48 hours of incubation significantly increased in the PCOS group. However, after 72 hours, TNF-α secretion significantly decreased in the PCOS group. The ability of PBMCs to produce TNF-α decreased gradually in women with PCOS. When the effects of low-grade inflammation and endocrine conditions on the cells decrease, the inability of PBMCs to create an inflammatory response will be altered.

Novel PGM3 mutation in two siblings with combined immunodeficiency and childhood bullous pemphigoid: a case report and review of the literature

BACKGROUND

Bullous pemphigoid is the most common autoimmune subepidermal blistering disorder with a low incidence in childhood. Combined immunodeficiencies (CIDs) are a group of monogenic inborn errors of immunity (IEIs) characterized by T- and B-cell dysfunction leading to recurrent infections, lymphoproliferation, predisposition to malignancy, and autoimmunity. Here, we report two Afghan siblings with a diagnosis of CID and extremely rare manifestation of diffuse bullous pemphigoid skin lesions.

CASE PRESENTATION

The older sibling (patient 1) was a 32-month-old male with facial dysmorphism, protracted diarrhea, failure to thrive, recurrent oral candidiasis, recurrent otitis media with tympanic membrane perforation, who had been previously diagnosed with CID. While he was under treatment with intravenous immunoglobulin (IVIg), he developed extensive blistering lesions, which were diagnosed as childhood bullous pemphigoid. Methylprednisolone and azathioprine were added to the regimen, which resulted in a remarkable improvement of the skin lesions and also the feeding condition. However,2 weeks later, he was re-admitted to the intensive care unit (ICU) and eventually died due to fulminant sepsis. Later, his 12-month-old sister (patient 2) with similar facial dysmorphism and a history of developmental delay, food allergy, recurrent oral candidiasis, and respiratory tract infections also developed blistering skin lesions. She was under treatment for occasional eczematous lesions, and had been receiving IVIg for 3 months due to low levels of immunoglobulins. Further immunologic workup showed an underlying CID and thus treatment with IVIg continued, gradually improving her clinical condition. The genetic study of both siblings revealed a novel homozygous mutation in exon 7 of the PGM3 gene, c.845 T > C (p.Val282Ala).

CONCLUSIONS

Dermatologic disorders may be the presenting sign in patients with CID and mutated PGM3. This case report further extends the spectrum of skin manifestations that could be observed in PGM3 deficiency and emphasizes the importance of considering CIDs during the assessment of skin disorders, particularly if they are extensive, recurrent, refractory to treatment, and/or associated with other signs of IEIs.

Recalcitrant Cutaneous Warts in a Family with Inherited ICOS Deficiency

Recalcitrant warts, caused by human papillomaviruses (HPVs), can be a cutaneous manifestation of inborn error of immunity. This study investigated the clinical manifestations, immunodeficiency, single-gene susceptibility, and HPV repertoire in a consanguineous family with severe sinopulmonary infections and recalcitrant warts. Clinical and immunologic evaluations, including FACS and lymphocyte transformation test, provided evidence for immunodeficiency. Combined whole-exome sequencing and genome-wide homozygosity mapping were utilized to disclose candidate sequence variants. Whole-transcriptome sequencing was used to concomitantly investigate the HPV genotypes and the consequences of detected sequence variants in the host. The proband, a male aged 41 years, was found to be homozygous for the c.6delG, p.Lys2Asnfs∗17 variant in ICOS, encoding the inducible T-cell costimulator. This variant was located inside the 5 megabase of runs of homozygosity on 2q33.2. RNA sequencing confirmed the deleteriousness of the ICOS variant in three skin biopsies revealing significant downregulation of ICOS and its ligand, ICOSLG. Reads unaligned to the human genome were applied to 926 different viruses, and α-HPV57, β-HPV107, β-HPV14, and β-HPV17 were detected. Collectively, we describe a previously unrecognized inborn error of T-cell immunity to HPVs, indicating that autosomal recessive ICOS deficiency can underlie recalcitrant warts, emphasizing the immunologic underpinnings of recalcitrant warts at the nexus of human and viral genomic variation.

Human OTULIN haploinsufficiency impairs cell-intrinsic immunity to staphylococcal α-toxin

The molecular basis of interindividual clinical variability upon infection with Staphylococcus aureus is unclear. We describe patients with haploinsufficiency for the linear deubiquitinase OTULIN, encoded by a gene on chromosome 5p. Patients suffer from episodes of life-threatening necrosis, typically triggered by S. aureus infection. The disorder is phenocopied in patients with the 5p- (Cri-du-Chat) chromosomal deletion syndrome. OTULIN haploinsufficiency causes an accumulation of linear ubiquitin in dermal fibroblasts, but tumor necrosis factor receptor-mediated nuclear factor κB signaling remains intact. Blood leukocyte subsets are unaffected. The OTULIN-dependent accumulation of caveolin-1 in dermal fibroblasts, but not leukocytes, facilitates the cytotoxic damage inflicted by the staphylococcal virulence factor α-toxin. Naturally elicited antibodies against α-toxin contribute to incomplete clinical penetrance. Human OTULIN haploinsufficiency underlies life-threatening staphylococcal disease by disrupting cell-intrinsic immunity to α-toxin in nonleukocytic cells.

Pulmonary Radiological Manifestations of Humoral and Combined Immunodeficiencies in a Tertiary Pediatric Center

Respiratory diseases are considered as significant causes of morbidity and mortality in primary immunodeficiencies. This study aimed to reveal the radiologic patterns of thoracic involvement in these disorders. A total of 58 patients, including 38 cases with combined cellular-humoral and 20 cases with humoral immunodeficiencies, were enrolled in this study. The "combined" group consisted of 12 cases with severe combined immunodeficiency (SCID) and 26 cases with combined immunodeficiency. The "humoral" group included seven patients with Hyper IgM syndrome (HIGMs), seven cases with common variable immunodeficiency (CVID), three patients with X-linked agammaglobulinemia, and three patients with other types of humoral primary immunodeficiencies (PIDs). The mean age of patients at the time of evaluation was 3.3±3.8 and 5.3±3.9 years in combined and humoral groups, respectively. The findings of chest X-rays and CT scans were interpreted and compared. There was a significant difference for alveolar opacification between combined and humoral immunodeficiencies (58% vs. 30%). The bronchopneumonia-like pattern was detected as a significant finding in patients with SCID (42%) and HIGMs (43%). Atrophy of the thymus was detected significantly often in cases of SCID (67%). Two patients with CVID and lipopolysaccharide-responsive and beige-like anchor protein deficiency showed parenchymal changes of granulomatous lymphocytic interstitial lung disease. No significant difference was detected for bronchiectasis, bronchitis/bronchiolitis patterns, pleural effusion, and thoracic lymphadenopathy. Distinct subtypes of primary immunodeficiency may provoke differing and comparable radiological patterns of thoracic involvement; which can clue the clinician and radiologist to the diagnosis of the disease.

The Effect of COVID-19 Pandemic on the Infants' Microbiota and the Probability of Development of Allergic and Autoimmune Diseases

The human microbiota plays a significant role in various mechanisms of the body. The formation of a healthy microbiota, especially in early childhood, has a significant effect on maintaining human health. Since the onset of coronavirus disease 2019 (COVID-19), the disease has caused many changes in human life. According to the available information, many of these factors affect the composition and diversity of the body's microbiota, so this pandemic may alter and disrupt the microbiota and consequently increase the incidence of other diseases such as allergic and autoimmune disorders, especially in children and infants born in this era. In this review, the probable impact of the COVID-19 pandemic on body's microbiota and its relationship with the emergence of future diseases is discussed.

Oral Wheat Immunotherapy: Long-Term Follow-Up in Children with Wheat Anaphylaxis

INTRODUCTION

There has been substantial increase in food allergies in recent decades. The management of severe food allergy often includes strict avoidance and medical therapies. However, oral immunotherapy (OIT) is a promising treatment option for these patients, which is still being investigated.

METHODS

The study recruited children from 2 years onward with a history of wheat anaphylaxis who had been referred to the Mofid Children Hospital. Wheat allergy was confirmed by a double-blind placebo-controlled food challenge. OIT was started to reach 5.28 g of wheat protein supplied in 60 g of bread. Besides immunologic measurements, a second and third oral food challenge (OFC) was performed after 3 months and 1 year of maintenance therapy to evaluate the long-term efficacy of wheat OIT (WOIT).

RESULTS

Seventeen patients completed the 3-month maintenance phase; 8 of them demonstrated negative OFCs. All of the 9 with positive OFCs were asked to continue the daily consumption of 60 g of bread for another year. Three patients with positive OFCs were followed for 1 more year and were asked to continue eating 60 g of bread every other day. The serum level of wheat sIgE was significantly increased at the end of the buildup phase (p = 0.026) and dramatically dropped at the end of the maintenance phase (p = 0.022).

CONCLUSION

To conclude, WOIT is an effective and safe modality of treatment if it is administered under strict supervision.

Autoimmune manifestations among 461 patients with monogenic inborn errors of immunity

BACKGROUND

The inborn errors of immunity (IEIs) are a group of heterogeneous disorders mainly characterized by severe and recurrent infections besides other complications including autoimmune and inflammatory diseases. In this study, we aim to evaluate clinical, immunologic, and molecular data of monogenic IEI patients with and without autoimmune manifestations.

METHODS

We have retrospectively screened cases of monogenic IEI in the Iranian PID registry for the occurrence of autoimmunity and immune dysregulation. A questionnaire was filled for all qualified patients with monogenic defects to evaluate demographic, laboratory, clinical, and molecular data.

RESULTS

A total of 461 monogenic IEI patients (290 male and 171 female) with a median (IQR) age of 11.0 (6.0-20.0) years were enrolled in this study. Overall, 331 patients (72.1%) were born to consanguineous parents. At the time of the study, 330 individuals (75.7%) were alive and 106 (24.3%) were deceased. Autoimmunity was reported in 92 (20.0%) patients with a median (IQR) age at autoimmune diagnosis of 4.0 (2.0-7.0) years. Sixteen patients (3.5%) showed autoimmune complications (mostly autoimmune cytopenia) as the first presentation of the disease. Most of the patients with autoimmunity were diagnosed clinically with common variable immunodeficiency (42.4%). The frequency of sinusitis and splenomegaly was significantly higher in patients with autoimmunity than patients without autoimmunity. In patients with autoimmunity, the most common pathogenic variants were identified in LRBA (in 21 patients, 23.0%), ATM (in 13 patients, 14.0%), and BTK (in 9 patients, 10.0%) genes. In the evaluation of autoimmunity by different genes, 4 of 4 IL10RB (100%), 3 of 3 AIRE (100%), and 21 of 30 LRBA (70.0%) mutated genes had the highest prevalence of autoimmunity.

CONCLUSIONS

Autoimmune phenomena are common features among patients with monogenic IEI and are associated with a more complicated course of the disease. Therefore, when encountering autoimmune disorders, especially in the setting of dysgammaglobulinemia, it would be appropriate to conduct next-generation sequencing to discover responsible genes for the immune dysregulation at an early stage of the disease.

The Prevalence of Atopic Manifestations in 313 Iranian Patients with Inborn Errors of Immunity

INTRODUCTION

Inborn errors of immunity (IEIs) are rare inherited disorders with a broad spectrum of manifestations. Here, we aimed to delineate the atopy burden in a cohort of patients with IEIs.

METHODS

313 patients with IEIs were enrolled in the study within a 9-years period, and data were collected via a questionnaire. All statistical analyses were performed using SPSS software (v. 25.0, Chicago, IL, USA). The statistical significance level was set at p < 0.05.

RESULTS

Overall, 51 out of 313 (16.3%) patients were identified to have atopic manifestations. Food allergy was detected in 34 (10.2%), atopic dermatitis in 21 (6.7%), as well as allergic asthma and allergic rhinitis each in 4 (1.3%) patients. The allergic disorders were reported as initial manifestations among 14 out of 35 (40.0%) atopic patients. Most of these 51 patients fell within the category of combined immunodeficiency (CID) (n = 38, 74.5%), followed by, severe CID (SCID) (n = 5, 9.8%), common variable immunodeficiency (n = 3, 5.9%), chronic granulomatous disease (n = 3, 5.9%), selective IgA deficiency (n = 1, 2.0%), and leukocyte adhesion defect (n = 1, 2.0%). No patient with Mendelian susceptibility to mycobacteria was found to have atopic manifestation. Atopic dermatitis (p = 0.001) and food allergy (p < 0.001) were both significantly higher in patients with CID than in other IEI groups. Among atopic patients with CID and SCID, food allergy and atopic dermatitis were the most prevalent comorbidities.

DISCUSSION/CONCLUSION

Atopic diseases may contribute to the clinical picture of IEIs, particularly in patients with CID. Atopy in association with other warning signs of IEIs increases the possibility of an underlying IEI.

The Prevalence of Selective and Partial Immunoglobulin A Deficiency in Patients with Autoimmune Polyendocrinopathy

Background: Autoimmune disorders are reported as presenting signs in patients with immunoglobulin A (IgA) deficiency. Herein, we aim to evaluate serum IgA among patients with autoimmune polyendocrinopathy.Methods: Patients with two or more autoimmune endocrinopathies were selected and the serum IgA levels were measured. Patients with an isolated low serum IgA (<7 mg/dL) after exclusion of other causes of hypogammaglobulinemia were considered as selective IgA deficiency (SIgAD), while partial IgA deficiency (PIgAD) was defined as IgA levels below lower limits of IgA normal range for age but higher than 7 mg/dL.Results: Fifty-three patients (19 [35.8%] male and 34 [64.2%] female) with autoimmune polyendocrinopathy enrolled in the study. Parental consanguinity and positive family history of autoimmunity were reported in 38.0% and 52.9% of patients, respectively. Overall, IgA deficiency was observed in 5 (9.4%) patients including PIgAD in 3 (5.7%) and SIgAD in 2 (3.8%) patients. Among IgA deficient patients, the first autoimmune disorder was developed at earlier ages (p = .002), and the prevalence of infection (p = .002), lymphoproliferation (p = .021), and overlap between insulin-dependent diabetes mellitus and autoimmune thyroiditis (p = .032) were significantly higher than patients with normal IgA. Also, the number of autoimmune comorbidities was closely correlated with the occurrence of IgA deficiency (p = .008).Conclusion: The prevalence of IgA deficiency in patients with autoimmune polyendocrinopathy is higher than that in the general population. In these patients, immunologic workup may lead to early diagnosis of inborn error of immunity, which can positively impact the evolution of complications and even management of the autoimmune disorders.

Increased regulatory T cells in peripheral blood of children with eosinophilic esophagitis

AIM

Considering the allergic basis of Eosinophilic esophagitis (EoE), this study was conducted to evaluate peripheral blood Tregs in children with EoE.

BACKGROUND

Eosinophilic esophagitis (EoE) is an allergic inflammatory disease of gastrointestinal tract. Regulatory T cells (Tregs) have a confirmed role in allergic disorders.

METHODS

Children with EoE, gastroesophageal reflux disease (GERD) and healthy controls (HC) (10 subjects in each group) were recruited after diagnosis by a pediatric gastroenterologist and allergist. After obtaining informed written consent, peripheral blood was obtained. Peripheral blood mononuclear cells were isolated by Ficoll gradient centrifugation. Flowcytometry was used to enumerate peripheral blood Tregs (CD₄ ⁺CD₂₅ ⁺FOXP3⁺ gated lymphocytes were considered as Tregs).

RESULTS

CD4⁺ gated lymphocytes significantly increased in EoE and GERD groups compared to HC group (p= 0.018). Tregs also was significantly increased in EoE in comparison to HC group (p=0.016). There were no statistically significant differences in Tregs of EoE as compared to GERD subjects (p=0.085).

CONCLUSION

Peripheral blood Tregs increase in patients with EoE as compared to healthy controls, which may be indicative of a feedback mechanism to regulate inflammatory responses.

Monogenic Primary Immunodeficiency Disorder Associated with Common Variable Immunodeficiency and Autoimmunity

BACKGROUND

Common variable immunodeficiency (CVID) is the most frequent primary immunodeficiency disorder mainly characterized by recurrent bacterial infections besides other immunological defects including loss of or dysfunction of B cells and decreased immunoglobulin levels. In this study, our aim is to evaluate clinical, immunological, and molecular data of patients with a primary clinical diagnosis of CVID and autoimmune phenotype with a confirmed genetic diagnosis.

METHODS

Among 297 patients with CVID, who were registered in the Iranian Primary Immunodeficiency Registry at Children's Medical Center Hospital in Iran, 83 patients have been genetically examined and 27 patients with autoimmunity and confirmed genetic mutations were selected for analysis. Whole-exome sequencing and confirmatory Sanger sequencing methods were used for the study population. A questionnaire was retrospectively filled for all patients to evaluate demographic, laboratory, clinical, and genetic data.

RESULTS

In the 27 studied patients, 11 different genetic defects were identified, and the most common mutated gene was LRBA, reported in 17 (63.0%) patients. Two patients (7.7%) showed autoimmune complications as the first presentation of immunodeficiency. Eleven patients (40.7%) developed one type of autoimmunity, and 16 patients (59.3%) progressed to poly-autoimmunity. Most of the patients with mono-autoimmunity (n = 9, 90.0%) primarily developed infectious complications, while in patients with poly-autoimmunity, the most common first presentation was enteropathy (n = 6, 37.6%). In 13 patients (61.9%), the diagnosis of autoimmune disorders preceded the diagnosis of primary immunodeficiency. The most frequent autoimmune manifestations were hematologic (40.7%), gastrointestinal (48.1%), rheumatologic (25.9%), and dermatologic (22.2%) disorders. Patients with poly-autoimmunity had lower regulatory T cells than patients with mono-autoimmunity.

CONCLUSION

In our cohort, the diagnosis of autoimmune disorders preceded the diagnosis of primary immunodeficiency in most patients. This association highlights the fact that patients referring with autoimmune manifestations should be evaluated for humoral immunity.

Novel CD40LG Mutation in Two Cousins With Immunoglobulin Class Switch Recombinant Deficiency

The hyper-immunoglobulin M (HIGM) syndrome comprises a group of rare inherited immunodeficiency disorders characterized by normal or elevated levels of serum IgM with low or absent levels of serum IgG, IgA, and IgE. Patients with this syndrome usually present with a history of recurrent infections or opportunistic infections. Here, we report two male cousins from homozygote twin mothers. The first cousin presented with no signs or symptoms other than neutropenia, which was accidentally found in a routine blood test. Immunological workup in this patient showed undetectable IgG and IgA levels and normal IgM levels. The second cousin had a history of recurrent infections, and at the time of admission, he was diagnosed with Pneumocystis jirovecii infection. The immunologic workup of this patient showed undetectable IgG, decreased IgA, and increased IgM level. Due to their interesting family relationship, genetic analysis was performed, which detected a novel mutation in exon 2 (c.266 del G) of the CD40 ligand gene (CD40LG).

Identifying Novel Mutations in Iranian Patients with LPS-responsive Beige-like Anchor Protein (LRBA) Deficiency

LPS-responsive beige-like anchor protein (LRBA) deficiency is a monogenic primary immunodeficiency characterized by a heterogeneous spectrum of clinical manifestations associated with immune dysregulation. In this study, we reported clinical, immunologic, and genetic evaluation of two Iranian patients from unrelated families, both suffering from recurrent respiratory tract infections, failure to thrive, interstitial lung disease, autoimmune cytopenia, and hypogammaglobulinemia. Pulmonary abscess in one patient and persistent enteropathy in another were also observed. Further investigations revealed causative mutations in the exon (c.2166_2766del) and intron (c.4730-3 T > G) of the LRBA gene. These results may provide further elucidation of the clinical phenotypes and responsible genetic factors of LRBA deficiency.

Rapid Desensitization for Hypersensitivity Reactions to Chemotherapeutic Drugs; A Case Series

Usage of cancer chemotherapeutics drugs can be associated with adverse drug reactions. When IgE-mediated drug reactions are formed following administration of a chemotherapeutics drug that is a drug of choice, drug desensitization protocols can be helpful. HSR can be allergic or nonallergic, but the clinical manifestations are similar. RDD is effective when used appropriately, however it is often over utilized instead of performing a drug challenge. RDD is both an acceptable approach and a high-risk treatment modality in patients, in whom the offending agent is the first choice in chemotherapy. The safety of this modality has been acceptable in large studies. The side effects are often less frequent and less severe by repeating the protocol. We present 4 cases of successful desensitization in cancer patients, who have developed IgE- mediated reactions to their major chemotherapy drug.

Increased number of regulatory T cells in esophageal tissue of patients with eosinophilic esophagitis in comparison to gastro esophageal reflux disease and control groups

BACKGROUND

Eosinophilic esophagitis (EoE) is a primarily polygenic allergic disorder. Although most patients have IgE sensitization, it seems that non-IgE mediated responses mainly contribute to the pathogenesis of EoE. Regulatory T cells (Tregs) may have an important role in allergies. There are limited data on the association of Tregs and EoE. In this study, we enumerated and compared T lymphocytes and Tregs in esophageal tissue of patients with EoE, gastroesophageal reflux disease (GERD) and normal controls.

METHODS

Ten patients with EoE, ten patients with GERD and eight normal controls were included. Immunohistochemistry staining was used to enumerate T lymphocytes and Tregs. CD3+ cells were considered as T cells and FOXP3+, CD3+ cells were considered as Tregs. T cells and Tregs were counted in 10 high power fields (HPF) (×400) for each patient and the average of 10 HPFs was recorded.

RESULTS

The mean±SEM of Tregs in esophageal tissue of patients with EoE (10.90±2.14cells/HPF) was significantly higher than the GERD (2.77±0.66cells/HPF) and control groups (0.37±0.08cells/HPF) (P<0.001). Additionally, the mean±SEM of T lymphocytes in esophageal tissue of patients with EoE (24.39±3.86cells/HPF) were increased in comparison to the GERD (10.07±2.65cells/HPF) and control groups (3.17±0.93cells/HPF) (P<0.001).

CONCLUSION

There is an increase in the number of esophageal T lymphocytes and regulatory T cells in patients with EoE compared to the GERD and control groups.

Fourth Update on the Iranian National Registry of Primary Immunodeficiencies: Integration of Molecular Diagnosis

BACKGROUND

The number of inherited diseases and the spectrum of clinical manifestations of primary immunodeficiency disorders (PIDs) are ever-expanding. Molecular diagnosis using genomic approaches should be performed for all PID patients since it provides a resource to improve the management and to estimate the prognosis of patients with these rare immune disorders.

METHOD

The current update of Iranian PID registry (IPIDR) contains the clinical phenotype of newly registered patients during last 5 years (2013-2018) and the result of molecular diagnosis in patients enrolled for targeted and next-generation sequencing.

RESULTS

Considering the newly diagnosed patients (n = 1395), the total number of registered PID patients reached 3056 (1852 male and 1204 female) from 31 medical centers. The predominantly antibody deficiency was the most common subcategory of PID (29.5%). The putative causative genetic defect was identified in 1014 patients (33.1%) and an autosomal recessive pattern was found in 79.3% of these patients. Among the genetically different categories of PID patients, the diagnostic rate was highest in defects in immune dysregulation and lowest in predominantly antibody deficiencies and mutations in the MEFV gene were the most frequent genetic disorder in our cohort.

CONCLUSIONS

During a 20-year registration of Iranian PID patients, significant changes have been observed by increasing the awareness of the medical community, national PID network establishment, improving therapeutic facilities, and recently by inclusion of the molecular diagnosis. The current collective study of PID phenotypes and genotypes provides a major source for ethnic surveillance, newborn screening, and genetic consultation for prenatal and preimplantation genetic diagnosis.

A Variety of Alu-Mediated Copy Number Variations Can Underlie IL-12Rβ1 Deficiency

PURPOSE

Inborn errors of IFN-γ immunity underlie Mendelian susceptibility to mycobacterial disease (MSMD). Autosomal recessive complete IL-12Rβ1 deficiency is the most frequent genetic etiology of MSMD. Only two of the 84 known mutations are copy number variations (CNVs), identified in two of the 213 IL-12Rβ1-deficient patients and two of the 164 kindreds reported. These two CNVs are large deletions found in the heterozygous or homozygous state. We searched for novel families with IL-12Rβ1 deficiency due to CNVs.

METHODS

We studied six MSMD patients from five unrelated kindreds displaying adverse reactions to BCG vaccination. Three of the patients also presented systemic salmonellosis, two had mucocutaneous candidiasis, and one had disseminated histoplasmosis. We searched for CNVs and other variations by IL12RB1-targeted next-generation sequencing (NGS).

RESULTS

We identified six new IL-12Rβ1-deficient patients with a complete loss of IL-12Rβ1 expression on phytohemagglutinin-activated T cells and/or EBV-transformed B cells. The cells of these patients did not respond to IL-12 and IL-23. Five different CNVs encompassing IL12RB1 (four deletions and one duplication) were identified in these patients by NGS coverage analysis, either in the homozygous state (n = 1) or in trans (n = 4) with a single-nucleotide variation (n = 3) or a small indel (n = 1). Seven of the nine mutations are novel. Interestingly, four of the five CNVs were predicted to be driven by nearby Alu elements, as well as the two previously reported large deletions. The IL12RB1 locus is actually enriched in Alu elements (44.7%), when compared with the rest of the genome (10.5%).

CONCLUSION

The IL12RB1 locus is Alu-enriched and therefore prone to rearrangements at various positions. CNVs should be considered in the genetic diagnosis of IL-12Rβ1 deficiency.

Severe Combined Immunodeficiency: A Case Series and Review from a Tertiary Pediatric Hospital

Severe combined immunodeficiency syndrome (SCID) is a life-threatening condition leading to early infant death as a result of severe infection, due to impaired cellular and humoral immune systems. Various forms of SCID are classified based on the presence or absence of T cells, B cells and natural killer cells. Patients usually present with recurrent infections and failure to thrive. Definitive treatment is hematopoietic stem cell transplantation. To achieve the best outcome, it should be performed prior to the development of severe infection. In This study, we described 10 patients (6 male and 4 female) with SCID who were admitted to Mofid Children Hospital, Tehran, Iran, from 2006 to 2013. We reviewed patients' clinical manifestation, laboratory data, family history and outcome. The mean age at the time of diagnosis was 131.8 days. One patient had non-consanguineous parents. Seven patients received BCG vaccine before the diagnosis of SCID, three of them showed disseminated BCG infection. One patient presented with invasive pulmonary aspergillosis. Flow cytometric analysis showed T⁻B⁺NK⁻ in three patients, T⁻B⁻NK⁺ in five patients, T⁻B⁻NK⁻ in one patient, and T⁻B⁺NK⁺ in one patient. This study highlights the importance of early diagnosis and patient referral before the occurrence of serious infection.

Is the Atopy Patch Test Reliable in the Evaluation of Food Allergy-Related Atopic Dermatitis?

BACKGROUND

Aeroallergens and food allergens are found to be relevant in atopic dermatitis. The atopy patch test (APT) can help to detect food allergies in children with atopic dermatitis. This study evaluates if the APT is a valuable tool in the diagnostic workup of children with food allergy-related atopic dermatitis.

METHODS

42 children between 6 months and 12 years of age were selected at the Mofid Children Hospital. Atopic dermatitis was diagnosed, and the severity of the disease was determined. At the test visit, the patients underwent a skin prick test (SPT), APT, and serum IgE level measurement for cow's milk, egg yolk, egg white, wheat, and soy.

RESULTS

We found a sensitivity of 91.7%, a specificity of 72.7%, a positive predictive value (PPV) of 88%, a negative predictive value (NPV) of 80%, and an accuracy of 85.7% for APT performed for cow's milk. APT performed for egg yolk had a sensitivity and a NPV of 100%, while the same parameters obtained with egg white were 84.2 and 75%, respectively. The sensitivity, specificity, and NPV of the APT for wheat were 100, 75, and 100%, respectively. The sensitivity, PPV, and NPV of the APT for soy were 87.5, 70, and 87.5%, respectively.

CONCLUSIONS

Our data demonstrate that the APT is a reliable diagnostic tool to evaluate suspected food allergy-related skin symptoms in childhood and infancy.

Targeted Gene Panel Sequencing for Early-onset Inflammatory Bowel Disease and Chronic Diarrhea

BACKGROUND

In contrast to adult-onset inflammatory bowel disease (IBD), where many genetic loci have been shown to be involved in complex disease etiology, early-onset IBD (eoIBD) and associated syndromes can sometimes present as monogenic conditions. As a result, the clinical phenotype and ideal disease management in these patients often differ from those in adult-onset IBD. However, due to high costs and the complexity of data analysis, high-throughput screening for genetic causes has not yet become a standard part of the diagnostic work-up of eoIBD patients.

METHODS

We selected 28 genes of interest associated with monogenic IBD and performed targeted panel sequencing in 71 patients diagnosed with eoIBD or early-onset chronic diarrhea to detect causative variants. We compared these results to whole-exome sequencing (WES) data available for 25 of these patients.

RESULTS

Target coverage was significantly higher in the targeted gene panel approach compared with WES, whereas the cost of the panel was considerably lower (approximately 25% of WES). Disease-causing variants affecting protein function were identified in 5 patients (7%), located in genes of the IL10 signaling pathway (3), WAS (1), and DKC1 (1). The functional effects of 8 candidate variants in 5 additional patients (7%) are under further investigation. WES did not identify additional causative mutations in 25 patients.

CONCLUSIONS

Targeted gene panel sequencing is a fast and effective screening method for monogenic causes of eoIBD that should be routinely established in national referral centers.

A gain-of-function mutation of STAT1: A novel genetic factor contributing to chronic mucocutaneous candidiasis

Heterozygous gain-of-function (GOF) mutations in the signal transducer and activator of transcription 1 (STAT1) have increasingly been identified as a genetic cause of autosomal-dominant (AD) chronic mucocutaneous candidiasis (CMC). In this article, we describe a 33-year-old man who experienced chronic refractory candidiasis, recurrent otitis media, and pneumonia resulting in bronchiectasis, severe oral and esophageal candidiases with strictures associated with hypothyroidism and immune hemolytic anemia. His son also suffered from persistent candidiasis, chronic diarrhea, poor weight gain, and pneumonia that resulted in his demise because of sepsis. The immunological workup showed that an inverse CD4/CD8 ratio and serum immunoglobulins were all within normal ranges. The laboratory data revealed failure in response to Candida lymphocyte transformation test. In addition, by Sanger sequencing method, we found a heterozygous mutation, Thr385Met (T385M), located in the DNA-binding domain of STAT1, which was previously shown to be GOF. These findings illustrate the broad and variable clinical phenotype of heterozygous STAT1 GOF mutations. However, more clinical information and phenotype-genotype studies are required to define the clinical phenotype caused by AD STAT1 GOF.

Clinical, Laboratory, and Molecular Findings for 63 Patients With Severe Combined Immunodeficiency: A Decade´s Experience

BACKGROUND

Severe combined immunodeficiency (SCID) is a life-threatening pediatric disease. We report on the clinical evaluation, immunological assessment, molecular analysis, and outcomes of SCID patients in a tertiary referral center in Iran.

METHODS

From January 2006 to December 2015, we performed a prospective cohort study in which initial screening and advanced immunological tests were carried out on patients suspected of having SCID. Genetic analysis was also performed to confirm the diagnosis.

RESULTS

A total of 63 patients were diagnosed with SCID (43 male [68.3%]). The median age at onset and diagnosis and diagnostic delay were 40 and 110 and 60 days respectively. A total of 49 patients (77.8%) had a history of BCG vaccination, and of these, one-third experienced BCG-associated complications. The most common clinical manifestations were pneumonia, recurrent oral candidiasis, chronic diarrhea, and failure to thrive. Of the thirteen patients who underwent hematopoietic stem cell transplantation, 8 survived and 5 died before they could receive the transplant. Most patients (34.9%) were classified as having T-B-NK+ SCID and had a mutation in the RAG2 or RAG1 gene.

CONCLUSIONS

Autosomal recessive SCID is the most common type in Iranian patients. Providing high-quality training to physicians and patients' families to reduce the diagnostic delay should be prioritized. It is also important to raise awareness of live vaccination and to expand stem cell donor registries to speed up the transplantation process.

Cow's Milk Desensitization in Anaphylactic Patients: A New Personalized-dose Method

Cow's milk allergy (CMA) is the most frequent food allergy in children and oral immunotherapy (OIT) is a promising approach for treatment of patients. The most challenging cases are anaphylactic with coexisting asthma and proposing safe protocols is crucial especially in high risk groups. Considering that CMA varies among patients, an individualized OIT protocol would be beneficial to achieve a safer and more efficient method of desensitization. 18 children more than 3 years of age with IgE-mediated CMA were enrolled. CMA was confirmed by positive skin prick test (SPT) and positive oral food challenge (OFC) and 60% of individuals had a convincing history of persistent asthma. SPT with milk extracts, whole fresh milk and serially diluted milk concentrations were performed.  The dilution of milk that induced 3-5 mm of wheal in each individual was selected as the starting dilution for OIT. Desensitization began by 1 drop of the defined dilution and continued increasingly. Overall, 16 out of 18 children (88.8%) achieved the daily intake of 120 mL of milk. Four out of these 16 children accomplished the protocol without any adverse allergic reactions. 12 patients experienced mild to severe reactions. Wheal and erythema in SPT (p≤0.001), and sIgE (p≤0.003) to most milk allergens were significantly decreased following desensitization. We successfully desensitized 16 of 18 children with IgE-mediated CMA by individualized desensitization protocol. Individualizing the OIT protocol would be helpful to save time and perhaps to relieve the allergic symptoms after ingesting cow's milk intake.

Evaluation of Lymphocyte Transformation Test Results in Patients with Delayed Hypersensitivity Reactions following the Use of Anticonvulsant Drugs

BACKGROUND/AIM

Administration of the anticonvulsant drugs phenobarbital, phenytoin, carbamazepine and lamotrigine can be associated with severe hypersensitivity reactions. The lymphocyte transformation test (LTT) is a method to determine which drug has caused the hypersensitivity reaction. This study was done to evaluate the results of LTT in patients with delayed hypersensitivity reactions following the administration of anticonvulsants.

METHODS

Twenty-four patients with hypersensitivity reactions, e.g. drug-induced hypersensitivity syndrome/drug rash and eosinophilia with systemic symptoms (DIHS/DRESS), Stevens-Johnson syndrome (SJS) and toxic epidermal necrosis (TEN), following the administration of anticonvulsant drugs, and 24 patients who had used anticonvulsant drugs but did not have hypersensitivity reactions (the control group) were included in this study. Peripheral blood mononuclear cells were isolated. The cells were stimulated with the drugs, phytohemagglutinin as a mitogen and Candida as an antigen (positive controls). Lymphocyte proliferation was measured using the BrdU proliferation assay kit (Roche, Germany). The stimulation index was calculated as the mean ratio of the OD of stimulated cells divided by the OD of unstimulated cells. The results in the case and control groups were compared.

RESULTS

Of 24 patients in the test group, 14 (58.3%) had positive LTT results and 10 (41.7%) had negative results. Among patients in the control group, 1 (4.2%) had a positive LTT result and 23 (95.8%) had negative results. Among the patients who had received carbamazepine and phenytoin, there was a significant difference between the results of LTT in the case and control groups (p = 0.002 and p = 0.028, respectively). Although patients receiving lamotrigine and phenobarbital had more positive LTT results in the case group than in the control group, these differences were not statistically significant. The sensitivity, specificity, positive predictive value and negative predictive value of LTT were 58.4, 95.8, 93.3 and 69.9%, respectively.

CONCLUSIONS

Considering the significant difference in LTT results between the case and control groups in patients receiving carbamazepine and phenytoin, and not observing such a difference in patients receiving phenobarbital and lamotrigine, LTT results are more valuable for the diagnosis of hypersensitivity reactions following the administration of carbamazepine and phenytoin. The LTT has good specificity but low sensitivity for the diagnosis of drug hypersensitivity reactions.

Long-term follow-up of ninety eight Iranian patients with primary immune deficiency in a single tertiary centre

PURPOSE

The aim was to describe the clinical manifestations, complications and long-term outcome of a cohort of Iranian patients with primary immune deficiency (PID).

METHOD

We retrospectively studied the demographic, clinical and immunological characteristics of the PID patients in a single tertiary centre, from January 1989 to July 2014. The patients were classified according to the International Union of Immunological Societies Expert Committee on PID.

RESULTS

98 patients were diagnosed with and followed-up for 15 disorders. The mean age at onset and diagnosis and the diagnostic delay were 8±10, 14.2±13.1 and 6.1±7 years, respectively. Parental consanguinity rate was 57%. Predominantly Antibody Deficiency was the most common diagnosis (n=63), followed by congenital defects of phagocytes (n=16), combined immunodeficiencies (n=12), well defined syndromes (n=4) and defects in innate immunity (n=3). Recurrent sinopulmonary infection was the most common presentation. Active infections were treated appropriately, in addition to prophylactic therapy with IVIG and antimicrobials. Not all the patients were compliant with prophylactic regimens due to cost and unavailability. One SCID patient underwent successful bone marrow transplantation. The total mortality rate was 19% during the follow-up period (7.8±7.6 years). The mean age of living patients at the time of study was 23±11.7 years.

CONCLUSIONS

Physicians awareness of PID has been rising dramatically in Iran, ensuring an increasing number of patients being diagnosed and treated. More effective treatment services, including health insurance coverage and drug availability are needed to improve the outcome of PID patients.

A Study on the Humoral and Complement Immune System of Patients with Organic Acidemia

Patients with organic acidemia are prone to different infections, which lead to acidosis episodes. Some studies have evaluated the status of immune system in acidotic phase in these patients, but to the best of our knowledge no study has evaluated the immune system in non-acidotic phase of the disease. In this study, thirty-one patients with organic acidemia were enrolled. For evaluation of humoral immunity, serum IgA, IgG, IgE, IgM, isohemaggltuinin titer, anti tetanus and anti diphtheria IgG were measured. For screening of complement deficiencies, serum C3, C4, and CH50 were assessed. Eleven patients had Maple Syrup Urine Disease (MSUD), 10 had methylmalonic acidemia, 5 had isovaleric acidemia, 4 had glutaric aciduria, and 1 had propionic acidemia. Serum IgM level was less than normal in 2 patients. Serum isohemagglutinin titer was less than 1:8 in 2 other patients. IgA, IgE, and IgG were within normal range for all patients. Anti tetanus and anti diphtheria IgG levels were low in two patients with MSUD. No significant relationship was found between any of the measured parameters and history of recurrent admissions, recurrent infections and the type of their diseases. Five patients had high C3 level, 4 had high C4 level, and 5 had high CH50 percentage. Totally, 10 patients had high complement level, but no remarkable connection was noted between the type of the disease and complement level. Minor insignificant deficiencies in humoral immunity in non-acidotic phase of organic acidemia were found. Some components of complement system showed increase in some patients, which might be due to decreased pH in extracellular fluid.

Increased expression of CD69 antigen on human peripheral blood natural killer cells in patients with allergic rhinitis

Allergic rhinitis (AR) is an inflammatory disorder of the nasal mucosa with high morbidity and prevalence. Natural killer (NK) cells might have a role in AR. We aimed to evaluate the changes of the markers and receptors on NK cells in AR patients compared to the non-atopic controls.Flow cytometric analysis was used with double staining of the Peripheral Blood Mononuclear Cells (PBMCs) to examine the expression of CD25 and CD69 markers, and NKG2D and NKG2A receptors on NK cells of 20 patients with AR and 20 non-atopic controls. The serum total IgE level was measured by Enzyme-linked Immunosorbent Assay.The expression of CD69 antigen on NK cells in AR patients was significantly higher than that of healthy group (p=0.03). No significant changes were observed between CD25, NKG2D and NKG2A expression on the surface of NK cells from healthy and AR subjects. Our study also showed that there was no significant correlation between the expression of CD69, CD25, NKG2D and NKG2A and level of serum total IgE in AR patients and normal subjects.These results indicated that the expression of CD69 antigen on NK cells of AR patients was increased. The high expression of CD69 on NK cells in AR patients suggested that these cells were activated, probably due to the cytokines secreted from allergen-stimulated T cells and activated monocytes.

A study of malnutrition in Iranian patients with primary antibody deficiency

Nutrition is an important factor that influences immunity, and nutritional deficiencies can impair resistance to infections. Malnutrition is the most common cause of immunodeficiency worldwide. Trace elements such as zinc, selenium, iron, and copper can influence several components of immunity. Primary antibody deficiency disorders are a group of disorders characterized by an unusual susceptibility to infections and malnutrition. Impaired nutritional status has been reported in immunodeficient patients. The aim of this study was to determine anthropometric indices and trace elements status in these patients. Thirty-eight children (28 males, 10 females, aged 2-18 years) with primary antibody deficiency referring to Children's Medical Center of Tehran University of Medical Science were enrolled in this research. Primary immunodeficiency disorders consisting of CVID, XLA, IgA deficiency, IgG subclass deficiency, and hyper IgM were assessed. Anthropometric indices, comprised of height, weight that were measured and body mass index (BMI) was calculated. Height-for-age (HAZ), weight-for-height (WHZ) and weight-for-age (WAZ) were determined according to Z-score to study mild, moderate and severe malnutrition. Serum copper, zinc, selenium and iron levels were measured by an atomic absorption spectrometer. The most common disorders were CVID 52.5% and X-linked agammaglobulinaemia 27.5%. Based on BMI measurements 21.1% of patients had malnutrition. According to HAZ, 13.2%, 13.2% and 36.8% had severe, moderate and mild malnutrition, respectively. According to WAZ, 10.5%, 18.4% and 28.6% had severe, moderate and mild malnutrition, respectively. Regarding to WHZ, 14.3% and 28.6% had moderate and mild malnutrition, respectively. Low selenium levels and high copper levels were observed in 37.5% and 70.3%, respectively. Anthropometric data showed that the frequency of malnutrition in these patients was higher than the CDC standard. Low serum selenium levels and high serum copper levels were observed, suggesting further research is needed on these parameters. Most of the patients had serum zinc and iron levels within the normal range. It is recommeded that clinical immunologists and nutritionists should make a collective effort to provide these patients with standard or specialized diets so as to decrease the risk of infection.

Natural killer cells in allergic rhinitis patients and nonatopic controls

BACKGROUND

Allergic rhinitis (AR) is currently considered to be a worldwide problem. The role of type 2 cytokines in this disease has been established, and natural killer (NK) cells are possibly the source of cytokine secretions. This study was performed to confirm the existence of type 2 cytokine-secreting NK cells in AR patients and to determine their characteristics.

METHODS

Twenty AR patients and 20 healthy nonatopic controls were included. Peripheral blood mononuclear cells were separated from heparinized blood by density gradient centrifugation. NK cells were enriched and cultured for 72 h. Cytokine secretion was measured by ELISA, and cytotoxicity assay was carried out using the PKH2-labeled K562 cell line. Intracytoplasmic cytokine staining and an analysis of surface markers of NK cells were performed on freshly isolated peripheral blood mononuclear cells using flow cytometry.

RESULTS

Patients with AR had a higher percentage of NK cells compared to nonatopic subjects. The mean percentage of IL-4+ NK cells was significantly higher and that of IFN-γ+ NK cells was nonsignificantly lower in AR patients compared to healthy nonatopic controls. IL-13 secretion was also significantly higher in AR patients compared to nonatopic controls. While there was no difference between the case and the control groups with regard to the surface expression of CD40, CD45RO, and CD95, the expression of CD178 was significantly higher in the cases when compared to the controls. NK cell cytotoxicity was also significantly higher in AR patients compared to healthy controls.

CONCLUSIONS

This study confirms the existence of type 2 cytokine-secreting NK cells in AR and shows their increased number and enhanced cytotoxicity compared to normal individuals.

Which cereal is a suitable substitute for wheat in children with wheat allergy?

Wheat is one of the main food allergens. It is among widely used cereals and there is an extensive cross-reaction between cereals. The aim of this study is to evaluate the extent to which cereals cross-react and to find the best substitute for wheat. Eighteen patients with definite diagnosis of type I hypersensitivity reactions to wheat enrolled in this study. Measurement of serum-specific IgE and skin prick test (SPT) for cereals flour (wheat, barley, oat, rye, rice and corn) and wheat bran was carried out. Also, open food challenge tests with available and conventional cereals in Iranian food culture (wheat, corn, rice and barley) were carried out. The SPTs were positive in 44.4% of patients for barley, 94.5% for wheat and 44-77% for other cereals. Positive serum-specific IgE was remarkable for wheat and barley and there was correlation between wheat and barley-specific IgE concentrations (r = 0.773 and p < 0.01). Corn serum-specific IgE was measured in 10 patients, which were positive in six of them. Of the patients, 55.5% had positive barley challenge tests, but all corn and rice challenge tests were negative. The best substitutes for wheat in wheat allergic patients are rice and corn. Regarding the correlation of wheat and barley serum-specific IgEs, there might be a high antigenic cross-reaction, therefore barley is not a good substitute for wheat and consuming barley needs a careful challenge test. Considering concordance of positive SPT to wheat flour and wheat bran, avoiding both of them is necessary in patients with wheat allergy.

Wheat allergy: clinical and laboratory findings

BACKGROUND

Food allergy affects 6-8% of infants and wheat allergy is one of the common food allergies among children. The clinical and laboratory manifestations of wheat allergy were evaluated in this study.

METHODS

Thirty-two children (< or =12 years old) with suspected wheat allergy were evaluated for wheat allergy. The patients underwent wheat skin prick test (SPT), measurement of wheat-specific IgE and wheat challenge test. The patients with a convincing history of anaphylaxis following ingestion of wheat or with a positive challenge test, and those with a history of immediate hypersensitivity reaction following ingestion of wheat in addition to a positive wheat SPT and/or positive wheat-specific IgE were considered wheat allergic. Then, the laboratory and clinical manifestations of their disease were studied.

RESULTS

Among patients with suspected wheat allergy, 24 patients with definite wheat allergy were identified. Anaphylaxis was a dominant clinical feature, accounting for 54.1% of acute symptoms. Chronic allergy symptoms like asthma and eczema were noted in 50% of the patients. Wheat-specific IgE was higher in patients with anaphylaxis (p<0.02) and the risk of anaphylaxis was 14.4 times more in patients with wheat-specific IgE equal to or more than 3+.

CONCLUSIONS

Anaphylaxis had occurred in a remarkable number of patients repeatedly, which demonstrates the severity of the reactions, poor knowledge of the disease and probable existence of more patients with mild reactions. Regarding the higher level of wheat-specific IgE in patients with anaphylaxis, wheat-specific IgE could be used to predict the severity of symptoms.