Kawarabi: Administrative Structuring of a Multicenter Research Collaborative to Study Kawasaki Disease in the Arab Countries

Kawasaki disease (KD), the leading cause of acquired heart disease in children in developed countries, merits conducting detailed studies in Arab countries. We introduce Kawarabi, as a multicenter research collaborative effort dedicated to improving diagnosis, care, and outcome of children and adults with KD in the Arab world. During the COVID-19 pandemic, there emerged a new multisystem inflammatory syndrome in children; a disease similar to KD. This highlighted the challenges that Arab physicians face in diagnosing and managing children with KD and KD-like illnesses. Kawarabi brings together experts in North America and Arab nations to study this family of diseases in a not-for-profit, voluntary scientific collaborative setting. Bylaws addressing the vision, objectives, structure, and governance of Kawarabi were established, and vetted by the 45 organizing members in 2021. An initial scientific publication showed evidence of a decreased level of awareness of the disease in the general population, as well as the lack of access to resources available for physicians caring for children with KD in Arab countries. Kawarabi has since held several educational webinars and an inaugural yearly meeting. The groundwork for future initiatives targeted at increasing awareness and understanding of the management and the long-term outcomes of children with KD in the region was established. Data on KD in the Arab world are lacking. Kawarabi is a multicenter research collaborative organization that has the unique resources, diversified ethnic makeup, and energy, to accomplish significant advances in our understanding and management of KD and its variants.

Access to Care and Therapy for Kawasaki Disease in the Arab Countries: A Kawasaki Disease Arab Initiative (Kawarabi) Multicenter Survey

Kawasaki Disease (KD) is still the most common acquired heart disease in children below the age of five years; it has been well described in the developed world; however, data from the Arab world are limited to case reports or single-center case series. In an effort of optimizing KD research in the Arab world, a group of physicians and researchers established the KD Arab Initiative (Kawarabi) in 2021, and published the first survey, which showed disparities in the availability of intravenous immunoglobulin (IVIG); this had prompted Kawarabi to assess the access to care and therapy of KD patients in Arab countries. A 32 structured questions survey was conducted in thirteen Arab countries and addressed KD patients' access to healthcare in urban and rural settings. The survey results showed that access to care was uniform across large, mid-size cities and rural areas in 7/13 (54%) countries, while in 6/13 (46%) countries, it was in favor of large and mid-size cities over rural areas. The quality of medical services received by children with KD in large cities was rated as excellent in 6/13 or good in 7/13 countries compared to fair in 4/13 or poor in 4/13 countries in rural areas. Availability of IVIG was limited (23%) in mid-size cities and almost impossible (23%) in rural areas. The KD patients in mid-size cities and rural areas have limited access to standard healthcare in the Arab world. This survey laid the foundation for future Kawarabi endeavors to improve the care of children with KD.

The Middle East and North Africa Diagnosis and Management Guidelines for Inborn Errors of Immunity

Human inborn errors of immunity (IEI) are a group of 485 distinct genetic disorders affecting children and adults. Signs and symptoms of IEI are heterogeneous, and accurate diagnosis can be challenging and depends on the available human expertise and laboratory resources. The Middle East and North Africa (MENA) region has an increased prevalence of IEI because of the high rate of consanguinity with a predominance of autosomal recessive disorders. This area also exhibits more severe disease phenotypes compared with other regions, probably due to the delay in diagnosis. The MENA-IEI registry network has designed protocols and guidelines for the diagnosis and treatment of IEI, taking into consideration the variable regional expertise and resources. These guidelines are primarily meant to improve the care of patients within the region, but can also be followed in other regions with similar patient populations.

Kawasaki Disease Arab Initiative [Kawarabi]: Establishment and Results of a Multicenter Survey

Studies on Kawasaki disease (KD) in Arab countries are scarce, often providing incomplete data. This along with the benefits of multicenter research collaboratives led to the creation of the KD Arab Initiative [Kawarabi] consortium. An anonymous survey was completed among potential collaborative Arab medical institutions to assess burden of KD in those countries and resources available to physicians. An online 32-item survey was distributed to participating institutions after conducting face validity. One survey per institution was collected. Nineteen physicians from 12 countries completed the survey representing 19 out of 20 institutions (response rate of 95%). Fifteen (79%) institutions referred to the 2017 American Heart Association guidelines when managing a patient with KD. Intravenous immunoglobulin (IVIG) is not readily available at 2 institutions (11%) yet available in the country. In one center (5%), IVIG is imported on-demand. The knowledge and awareness among countries' general population was graded (0 to 10) at median/interquartiles (IQR) 3 (2-5) and at median/IQR 7 (6-8) in the medical community outside their institution. Practice variations in KD management and treatment across Arab countries require solid proactive collaboration. The low awareness and knowledge estimates about KD among the general population contrasted with a high level among the medical community. The Kawarabi collaborative will offer a platform to assess disease burden of KD, among Arab population, decrease practice variation and foster population-based knowledge.

Inborn Errors of Immunity in Algerian Children and Adults: A Single-Center Experience Over a Period of 13 Years (2008–2021)

Background

Inborn errors of immunity (IEI) predispose patients to various infectious and non-infectious complications. Thanks to the development and expanding use of flow cytometry and increased awareness, the diagnostic rate of IEI has markedly increased in Algeria the last decade.

Aim

This study aimed to describe a large cohort of Algerian patients with probable IEI and to determine their clinical characteristics and outcomes.

Methods

We collected and analyzed retrospectively the demographic data, clinical manifestations, immunologic, genetic data, and outcome of Algerian IEI patients - diagnosed in the department of medical immunology of Beni Messous university hospital center, Algiers, from 2008 to 2021.

Results

Eight hundred and seven patients with IEI (482 males and 325 females) were enrolled, 9.7% of whom were adults. Consanguinity was reported in 50.3% of the cases and a positive family history in 32.34%. The medium age at disease onset was 8 months and at diagnosis was 36 months. The median delay in diagnosis was 16 months. Combined immunodeficiencies were the most frequent (33.8%), followed by antibody deficiencies (24.5%) and well-defined syndromes with immunodeficiency (24%). Among 287 patients tested for genetic disorders, 129 patients carried pathogenic mutations; 102 having biallelic variants mostly in a homozygous state (autosomal recessive disorders). The highest mortality rate was observed in patients with combined immunodeficiency (70.1%), especially in patients with severe combined immunodeficiency (SCID), Omenn syndrome, or Major Histocompatibility Complex (MHC) class II deficiency.

Conclusion

The spectrum of IEI in Algeria is similar to that seen in most countries of the Middle East and North Africa (MENA) region, notably regarding the frequency of autosomal recessive and/or combined immunodeficiencies.

Consensus Middle East and North Africa Registry on Inborn Errors of Immunity

Background

Inborn errors of immunity (IEIs) are a heterogeneous group of genetic defects of immunity, which cause high rates of morbidity and mortality mainly among children due to infectious and non-infectious complications. The IEI burden has been critically underestimated in countries from middle- and low-income regions and the majority of patients with IEI in these regions lack a molecular diagnosis.

Methods

We analyzed the clinical, immunologic, and genetic data of IEI patients from 22 countries in the Middle East and North Africa (MENA) region. The data was collected from national registries and diverse databases such as the Asian Pacific Society for Immunodeficiencies (APSID) registry, African Society for Immunodeficiencies (ASID) registry, Jeffrey Modell Foundation (JMF) registry, J Project centers, and International Consortium on Immune Deficiency (ICID) centers.

Results

We identified 17,120 patients with IEI, among which females represented 39.4%. Parental consanguinity was present in 60.5% of cases and 27.3% of the patients were from families with a confirmed previous family history of IEI. The median age of patients at the onset of disease was 36 months and the median delay in diagnosis was 41 months. The rate of registered IEI patients ranges between 0.02 and 7.58 per 100,000 population, and the lowest rates were in countries with the highest rates of disability-adjusted life years (DALY) and death rates for children. Predominantly antibody deficiencies were the most frequent IEI entities diagnosed in 41.2% of the cohort. Among 5871 patients genetically evaluated, the diagnostic yield was 83% with the majority (65.2%) having autosomal recessive defects. The mortality rate was the highest in patients with non-syndromic combined immunodeficiency (51.7%, median age: 3.5 years) and particularly in patients with mutations in specific genes associated with this phenotype (RFXANK, RAG1, and IL2RG).

Conclusions

This comprehensive registry highlights the importance of a detailed investigation of IEI patients in the MENA region. The high yield of genetic diagnosis of IEI in this region has important implications for prevention, prognosis, treatment, and resource allocation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10875-021-01053-z.

Diagnostic and Predictive Contribution of Autoantibodies Screening in a Large Series of Patients With Primary Immunodeficiencies

Objectives

To evaluate the diagnostic and predictive contribution of autoantibodies screening in patients with primary immunodeficiencies (PIDs).

Methods

In the present study, PID patients and healthy controls have been screened for 54 different autoantibodies. The results of autoantibodies screening in PID patients were correlated to the presence of autoimmune diseases.

Results

A total of 299 PID patients were included in this study with a predominance of antibody deficiencies (27.8%) followed by immunodeficiencies affecting cellular and humoral immunity (26.1%) and complement deficiencies (22.7%). Autoimmune manifestations were present in 82 (27.4%) patients. Autoimmune cytopenia (10.4%) was the most common autoimmune disease followed by gastrointestinal disorders (10.0%), rheumatologic diseases (3.7%), and endocrine disorders (3.3%). Autoantibodies were found in 32.4% of PID patients and 15.8% of healthy controls (P < 0.0005). Anti-nuclear antibodies (ANA) (10.0%), transglutaminase antibody (TGA) (8.4%), RBC antibodies (6.7%), anti-smooth muscle antibody (ASMA) (5.4%), and ASCA (5.0%) were the most common autoantibodies in our series. Sixty-seven out of the 82 patients with autoimmune manifestations (81.7%) were positive for one or more autoantibodies. Eleven out of the 14 patients (78.6%) with immune thrombocytopenia had positive platelet-bound IgM. The frequencies of ASCA and ANCA among patients with IBD were 47.4% and 21.0% respectively. All patients with celiac disease had TGA-IgA, while six out of the 11 patients with rheumatologic diseases had ANA (54.5%). Almost one third of patients (30/97) with positive autoantibodies had no autoimmune manifestations. ANA, rheumatoid factor, ASMA, anti-phospholipid antibodies and ANCA were often detected while specific AID was absent. Despite the low positive predictive value of TGA-IgA and ASCA for celiac disease and inflammatory bowel disease respectively, screening for these antibodies identified undiagnosed disease in four patients with positive TGA-IgA and two others with positive ASCA.

Conclusion

The present study provides valuable information about the frequency and the diagnostic/predictive value of a large panel of autoantibodies in PIDs. Given the frequent association of some AIDs with certain PIDs, screening for corresponding autoantibodies would be recommended. However, positivity for autoantibodies should be interpreted with caution in patients with PIDs due to their low positive predictive value.

Genetic Approaches for Definitive Diagnosis of Agammaglobulinemia in Consanguineous Families

Autosomal recessive agammaglobulinemia (ARA) is a primary immunodeficiency characterized by absent peripheral B cells, severe hypogammaglobulinemia, and absent BTK gene mutations. In ARA, mutations occur in genes encoding the pre-B cell receptor (pre-BCR) or downstream signaling proteins. In this work, we used candidate gene and whole-exome sequencing to investigate the molecular basis of ARA in 6 patients from 4 consanguineous North-African families. Sanger sequencing of candidate genes encoding the pre-BCR components (ΙGΗΜ, CD79A, CD79B, IGLL1, and VPREB1) was initially performed and determined the genetic defect in five patients. Two novel mutations in IGHM (p.Val378Alafs*1 and p.Ile184Serfs*21) were identified in three patients from two unrelated kindred and a novel nonsense mutation was identified in CD79A (p.Trp66*) in two siblings from a third kindred. Whole-exome sequencing (WES) was performed on the sixth patient who harbored a homozygous stop mutation at position 407 in the RAG2 gene (p.Glu407*). We concluded that conventional gene sequencing, especially when multiple genes are involved in the defect as is the case in ARA, is costly and time-consuming, resulting in delayed diagnosis that contributes to increased morbidity and mortality. In addition, it fails to identify the involvement of novel and unsuspected gene defects when the phenotype of the patients is atypical. WES has the potential to provide a rapid and more accurate genetic diagnosis in ARA, which is crucial for the treatment of the patients.

Virologic study of acute lower respiratory tract infections in children admitted to the paediatric department of Blida University Hospital, Algeria

Acute lower respiratory tract infections (ALRTI) such as pneumonia and bronchiolitis are major causes of mortality and morbidity in children under 5 years of age. The main microbial agents responsible for ALRTI are either bacterial agents (Streptococcus pneumoniae, Haemophilus influenzae type b, Mycoplasma pneumoniae) or viruses (respiratory syncytial virus (RSV, also known as human orthopneumovirus), Myxovirus influenzae, Myxovirus parainfluenzae, adenovirus) [1]. More recently, other viruses (rhinovirus, metapneumovirus, coronavirus, bocavirus) have been implicated in ALRTI; their identification has been facilitated by new molecular biology techniques such as real-time PCR. To our knowledge, these emerging viruses have never been the subject of epidemiologic studies in our country.

X-linked agammaglobulinemia (XLA):Phenotype, diagnosis, and therapeutic challenges around the world

Background

X-linked agammaglobulinemia is an inherited immunodeficiency recognized since 1952. In spite of seven decades of experience, there is still a limited understanding of regional differences in presentation and complications. This study was designed by the Primary Immunodeficiencies Committee of the World Allergy Organization to better understand regional needs, challenges and unique patient features.

Methods

A survey instrument was designed by the Primary Immunodeficiencies Committee of the World Allergy Organization to collect both structured and semi-structured data on X-linked agammaglobulinemia. The survey was sent to 54 centers around the world chosen on the basis of World Allergy Organization participation and/or registration in the European Society for Immunodeficiencies. There were 40 centers that responded, comprising 32 countries.

Results

This study reports on 783 patients from 40 centers around the world. Problems with diagnosis are highlighted by the reported delays in diagnosis>24 months in 34% of patients and the lack of genetic studies in 39% of centers Two infections exhibited regional variation. Vaccine-associated paralytic poliomyelitis was seen only in countries with live polio vaccination and two centers reported mycobacteria. High rates of morbidity were reported. Acute and chronic lung diseases accounted for 41% of the deaths. Unusual complications such as inflammatory bowel disease and large granular lymphocyte disease, among others were specifically enumerated, and while individually uncommon, they were collectively seen in 20.3% of patients. These data suggest that a broad range of both inflammatory, infectious, and autoimmune conditions can occur in patients. The breadth of complications and lack of data on management subsequently appeared as a significant challenge reported by centers. Survival above 20 years of age was lowest in Africa (22%) and reached above 70% in Australia, Europe and the Americas. Centers were asked to report their challenges and responses (n = 116) emphasized the difficulties in access to immunoglobulin products (16%) and reflected the ongoing need for education of both patients and referring physicians.

Conclusions

This is the largest study of patients with X-linked agammaglobulinemia and emphasizes the continued morbidity and mortality of XLA despite progress in diagnosis and treatment. It presents a world view of the successes and challenges for patients and physicians alike. A pivotal finding is the need for education of physicians regarding typical symptoms suggesting a possible diagnosis of X-linked agammaglobulinemia and sharing of best practices for the less common complications.

Primary Immunodeficiencies: Epidemiology in the Maghreb

INTRODUCTION

Primary Immunodeficiency (PIDs) is a set of 330 rare hereditary diseases that increase susceptibility to infections, allergies, autoimmunity, and neoplasia. North American registries give higher prevalence than Maghreb ones, whereas consanguinity is high. The purpose of this study is to compare prevalence and coverage rate of Maghreb PID registries with estimates based on USA.

METHODS

We searched the prevalence of PIDs in the Maghreb registers. Next, we estimated the expected values based on recent publications. Finally, we calculated the coverage rate of the Maghreb registries compared to the new estimates and we evaluated the impact of consanguinity.

RESULTS

The total number is N1 = 2456 patients. The current Maghreb PID Prevalence is 2.56 / 100,000 inhabitants (population of 94,804,694 Million in 2017). Tunisia leads with a prevalence of 8.70 followed by Morocco 2.09, Libya 1.65 and Algeria 1.46/100.000 habitants. We did not find values for Mauritania. If we extrapolate the prevalence of the USA to the Maghreb population, the number of patients in the Maghreb would be N2 = 27,588 and the coverage rate (N1 / N2) would be 8.90%. This low coverage rate is however better than the World average (1.21%), that of Latin America 1.19% and Africa 0.36%. The Maghreb prevalence is close to that of the Arab world 2.04 / 100,000 (population of 391,449,544 in 2017). Using the incidence found in the USA, the number of patients would be 9765 new patients per year in the Maghreb and 40,319 in Arab countries.

CONCLUSION

PID Maghreb patients number is very low compared to global estimates, whereas consanguinity is very high. Special attention should be given to PIDs by governments and research teams in this region.

Pertussis in north-central and northwestern regions of Algeria

INTRODUCTION

Pertussis outbreaks continue to occur in many countries despite high vaccination coverage. Under-diagnosed cases in adolescents and adults may result in increased transmission to infants, who are at risk of severe pertussis. Additional measures to protect both groups should be considered.

METHODOLOGY

Nasopharyngeal samples and sera were collected from patients and household contacts with clinically suspected pertussis. Diagnoses were confirmed by culture, real-time polymerase chain reaction (PCR), and serology. Bordetella pertussis isolates were characterized by antimicrobial sensitivity and fimbrial serotyping.

RESULTS

Of 392 participants, 134/248 patients (54%) and 66/144 contacts (45.8%) had confirmed pertussis infections. B. parapertussis was not detected. All B. pertussis isolates were sensitive to the antibiotics tested, and all expressed the Fim3, not the Fim2, fimbrial serotype. Most patients (81.2%) were <6 months (51.8% of whom were <3 months) of age; 77.6% were unvaccinated, and most positive contacts were mothers 20-40 years of age.

CONCLUSIONS

Despite high vaccination coverage, pertussis is circulating in Algeria. Most infections occur in unvaccinated infants <6 months of age, with mothers as the main source of infection. An adolescent/adult booster should be considered. Adoption of sensitive and specific laboratory tests would improve pertussis diagnosis and surveillance.

X-Linked Agammagobulinemia in a Large Series of North African Patients: Frequency, Clinical Features and Novel BTK Mutations

PURPOSE

X-linked agammagobulinemia (XLA) is a primary immunodeficiency caused by Bruton's tyrosine kinase (BTK) gene defect. XLA patients have absent or reduced number of peripheral B cells and a profound deficiency in all immunoglobulin isotypes. This multicenter study reports the clinical, immunological and molecular features of Bruton's disease in 40 North African male patients.

METHODS

Fifty male out of 63 (male and female) patients diagnosed with serum agammaglobulinemia and non detectable to less than 2% peripheral B cells were enrolled. The search for BTK gene mutations was performed for all of them by genomic DNA amplification and Sanger sequencing.

RESULTS

We identified 33 different mutations in the BTK gene in 40 patients including 12 missense mutations, 6 nonsense mutations, 6 splice-site mutations, 5 frameshift, 2 large deletions, one complex mutation and one in-frame deletion. Seventeen of these mutations are novel. This large series shows a lower frequency of XLA among male patients from North Africa with agammaglobulinemia and absent to low B cells compared with other international studies (63.5% vs. 85%). No strong evidence for genotype-phenotype correlation was observed.

CONCLUSIONS

This study adds to other reports from highly consanguineous North African populations, showing lower frequency of X-linked forms as compared to AR forms of the same primary immunodeficiency. Furthermore, a large number of novel BTK mutations were identified and could further help identify carriers for genetic counseling.

Eosinophilic pneumonias in children: A review of the epidemiology, diagnosis, and treatment

Pediatric eosinophilic pneumonias (EPs) are characterized by a significant infiltration of the alveolar spaces and lung interstitium by eosinophils, with conservation of the lung structure. In developed countries, EPs constitute exceptional entities in pediatric care. Clinical symptoms may be transient (Löffler syndrome), acute (<1 month and mostly <7 days), or chronic (>1 month). Diagnosis relies on demonstration of alveolar eosinophilia on bronchoalveolar lavage, whether or not associated with blood eosinophilia. EPs are a heterogeneous group of disorders divided into: (i) secondary forms (seen mainly in parasitic infections, allergic bronchopulmonary aspergillosis, and drug reactions); and (ii) primary forms (eosinophilic granulomatosis with polyangiitis, hypereosinophilic syndrome, idiopathic chronic eosinophilic pneumonia, and idiopathic acute eosinophilic pneumonia). Despite their rarity, the etiological approach to EP must be well-defined as some causes can be rapidly life-threatening without initiation of the proper treatment. This approach (i) eliminates secondary forms, with comprehensive history taking and minimal biological assessment, (ii) is oriented in primary forms by the acute or chronic setting, and the existence of extrapulmonary symptoms. Treatment of primary forms has traditionally relied on corticosteroids, usually with a dramatic response. Specific treatments or the adjunction of corticosteroid-sparing treatment or immunosuppressors are currently being evaluated in order to improve the prognosis and the side effects associated with corticosteroid treatment in a pediatric setting.

Prolongation of Hospital Stay and Additional Costs Due to Nosocomial Bloodstream Infection in an Algerian Neonatal Care Unit

Background.

Previous studies from developed countries reported that nosocomial bloodstream infection (BSI) in neonatal care units (NCUs) increases length of stay and costs. However, no such information is available for Algerian NCUs.

Objective.

To evaluate the influence of BSI in neonates on additional charges and length of hospital stay.

Design.

Prospective, nested case-control study.

Setting.

The 47-bed NCU of the University Hospital of Blida, Algeria.

Patients and Methods.

A total of 83 neonates with BSIs (case patients) and 166 neonates without BSIs (control patients), admitted to the NCU during the study period (April 2004 through December 2007), were matched for sex, birth weight, length of NCU stay, and year of hospital admission. Each patient's length of stay in the NCU was obtained prospectively on daily rounds. The estimated cost of each NCU-day was provided by the hospital's finance department. The cost of antibiotics prescribed was provided by the hospital's pharmacy department.

Results.

The mean additional length of NCU stay for case patients, compared with control patients, was 9.2 days (24.3 vs 15.1 days). The mean additional cost of antibiotics was $546. The mean cumulative additional cost was $1,315.

Conclusion.

This study highlights the effect of BSI on extra costs for NCU patients, especially costs due to prolongation of hospital stay and increased antibiotic use, and suggests that NCUs in Algeria have a financial interest in reducing the rate of BSI.

Foreign body aspiration in children: experience from 2624 patients

OBJECTIVES

The objective of this study is to analyze the epidemiological, clinical, radiological and endoscopic characteristics of pediatric foreign body aspiration in Algeria.

METHODS

In this retrospective study, the results of 2624 children younger than 18 years admitted in our department for respiratory foreign body removal between 1989 and 2012, were presented. Most of them had an ambulatory rigid bronchoscopy.

RESULTS

The children (62.34% males and 37.65% females) were aged 4 months to 18 years with 66% between 1 and 3 years. Choking was related in 65% of cases. The delay between aspiration and removal was 2-8 days in 65.8% and within 24 h in 9.2%. In the most cases, the children arrived with cough, laryngeal or bronchial signs and unilateral reduction of vesicular murmur. The examination was normal in 13%. The most common radiologic finding was pulmonary air trapping (40.7%). The aspirated bodies were organic in 66.7%, dominated by peanuts, while sunflower seeds, beans and ears of wheat were the most dangerous. In the other cases, they were metallic or plastic as pen caps and recently scarf pins. The endoscopic removal by rigid bronchoscopy was successful and complete in 97%. Cases with extraction failure (3%) limited to certain FBs, all of them inorganic were assigned to surgery. The complications related to the endoscopic procedure were 0.29% with a mortality of 0.26%.

CONCLUSION

Foreign body aspiration is a real public health problem in Algeria. The best way to manage it is an early diagnosis and a rigid bronchoscopy removal under general anesthesia used by fully trained staff. The prevention of this domestic accident should consider the population lifestyle and cultural habits to be more effective.

A new large CFTR rearrangement illustrates the importance of searching for complex alleles

The p.Val754Met variant, described in 1996 in a CF patient, has been considered a CF mutation. However, biochemical aspects, results of functional studies and, finally, the identification of a complex deletion removing exons 3 to 10 and 14b to 16 in cis of p.Val754Met in a CF patient, argue against a strong deleterious effect. An inventory through the French CF network of patients carrying p.Val754Met led to the registration of seven patients (CF: n=4; idiopathic chronic pancreatitis: n=3) and six healthy individuals, all heterozygous for the variation. Extensive CFTR gene analysis was carried out, including the search for large rearrangements and other possible mutations. The complex deletion, whose breakpoints are described here, was found only in the four CF patients, in association with the same haplotype. This data, added to the fact that the p.[Phe508del]+[Val754Met] genotype was found in a healthy individual, bring further arguments against the association of p.Val754Met with CF. We thus suggest looking for a possible complex allele whenever p.Val754Met is detected and considering it neutral regarding genetic counseling when found in isolation.