Major Loci on Chromosomes 8q and 3q Control Interferon γ Production Triggered by Bacillus Calmette-Guerin and 6-kDa Early Secretory Antigen Target, Respectively, in Various Populations.

BACKGROUND: Interferon γ (IFN-γ) release assays (IGRAs) provide an in vitro measurement of antimycobacterial immunity that is widely used as a test for Mycobacterium tuberculosis infection. IGRA outcomes are highly heritable in various populations, but the nature of the involved genetic factors remains unknown. METHODS: We conducted a genome-wide linkage analysis of IGRA phenotypes in families from a tuberculosis household contact study in France and a replication study in families from South Africa to confirm the loci identified. RESULTS: We identified a major locus on chromosome 8q controlling IFN-γ production in response to stimulation with live bacillus Calmette-Guerin (BCG; LOD score, 3.81; P = 1.40 × 10(-5)). We also detected a second locus, on chromosome 3q, that controlled IFN-γ levels in response to stimulation with 6-kDa early secretory antigen target, when accounting for the IFN-γ production shared with that induced by BCG (LOD score, 3.72; P = 1.8 × 10(-5)). Both loci were replicated in South African families, where tuberculosis is hyperendemic. These loci differ from those previously identified as controlling the response to the tuberculin skin test (TST1 and TST2) and the production of TNF-α (TNF1). CONCLUSIONS: The identification of 2 new linkage signals in populations of various ethnic origins living in different M. tuberculosis exposure settings provides new clues about the genetic control of human antimycobacterial immunity.

Cardiopulmonary Exercise Testing Provides Prognostic Information in Advanced Cystic Fibrosis Lung Disease.

Rationale: Cardiopulmonary exercise testing (CPET) provides prognostic information in cystic fibrosis (CF); however, its prognostic value for patients with advanced CF lung disease is unknown. Objectives: To determine the prognostic value of CPET on the risk of death or lung transplant (LTX) within 2 years. Methods: We retrospectively collected data from 20 CF centers in Asia, Australia, Europe, and North America on patients with a forced expiratory volume in 1 second (FEV1) ⩽ 40% predicted who performed a cycle ergometer CPET between January 2008 and December 2017. Time to death/LTX was analyzed using mixed Cox proportional hazards regression. Conditional inference trees were modeled to identify subgroups with increased risk of death/LTX. Results: In total, 174 patients (FEV1, 30.9% ± 5.8% predicted) were included. Forty-four patients (25.5%) died or underwent LTX. Cox regression analysis adjusted for age, sex, and FEV1 revealed percentage predicted peak oxygen uptake ([Formula: see text]o2peak) and peak work rate (Wpeak) as significant predictors of death/LTX: adjusted hazard ratios per each additional 10% predicted were 0.60 (95% confidence interval, 0.43-0.90; P = 0.008) and 0.60 (0.48-0.82; P < 0.001). Tree-structured regression models, including a set of 11 prognostic factors for survival, identified Wpeak to be most strongly associated with 2-year risk of death/LTX. Probability of death/LTX was 45.2% for those with a Wpeak ⩽ 49.2% predicted versus 10.9% for those with a Wpeak > 49.2% predicted (P < 0.001). Conclusions: CPET provides prognostic information in advanced CF lung disease, and Wpeak appears to be a promising marker for LTX referral and candidate selection.

Impact of the COVID-19 pandemic and associated lockdown measures on the management, health, and behavior of the cystic fibrosis population in France during 2020 (MUCONFIN).

Background: Most of the studies on cystic fibrosis (CF) focused on SARS-CoV-2 prevalence and suggested a low incidence of infection in this population. We aimed to assess the impact of the pandemic and related lockdown measures implemented in May 2020 in response to the first wave of SARS-CoV-2 infection on healthcare access, health, and behavior in CF patients. Methods: A national questionnaire opened online from May 15th, 2020 to June 11th, 2020 was completed by 751 CF-patients, aged 14 years and over. It comprised questions about access to healthcare, anxiety and depression, smoking, alcohol, drug and psychotropic drug consumption, adherence to CF treatment, and constraints. A semi-structured comprehensive interview was performed no later than 1 month after the end of the lockdown in 16 CF-patients. Results: The mean age of the population was 28.0 [interquartile range (IQR) 20.0-37.0] years old. More than 75% of in-person consultations scheduled during the lockdown were canceled. Alternatively, 27% were postponed, and telehealth consultations were proposed and accepted in almost 40% of cases. More than 75% of the scheduled physiotherapy sessions were canceled and replaced mainly by self-drainage. Annual follow-up clinic visits were consistently postponed whereas required hospitalizations at CF centers for exacerbation were maintained in most cases. While 43.2% CF-patients had signs of anxiety, 51.0% presented symptoms of depression, both associated with increased use of psychotic medications and inversely correlated to COVID-19 prevalence. Among the lower and lower middle classes, very little medical information was obtained or requested by the patient, participation to sports or other activities was low, while excessive home confinement and isolation were more frequent. In contrast, in the upper middle and upper classes, individuals solicitated help to their CF centre, had more physical activities, and maintained contact with friends or families. Conclusion: The first lockdown in France had only minimal impact on the management care of CF-patients but was associated with increased symptoms of anxiety and depression, together with behavioral changes that varied with social class. Trial registration: NCT04463628.

Unsolved severe chronic rhinosinusitis elucidated by extensive CFTR genotyping.

Severe chronic rhinosinusitis in children should alert clinicians and extensive CFTR genotyping should be performed. We propose that thorough clinical and functional assessment in severe chronic rhinosinusitis is valuable to discover rare mutations which could be treated by CFTR correctors to postpone pulmonary infection.

Non-invasive CT screening for pulmonary arteriovenous malformations in children with confirmed hereditary hemorrhagic telangiectasia: Results from two pediatric centers.

BACKGROUND: Hereditary hemorrhagic telangiectasia (HHT) is an autosomal dominant genetic disorder that is caused by mutations in mainly two genes, that is ENG, encoding endoglin (HHT1), or ACVRL1, encoding activin receptor-like kinase 1 (ALK-1/HHT2). HHT is characterized by recurrent epistaxis, mucocutaneous telangiectasia, and vascular visceral dysplasia responsible for visceral arteriovenous malformations (AVM). AIM: to report the experience of two university hospitals (Trousseau, Paris, and CHIC, Creteil) with screening children for HHT and pulmonary AVM (PAVM) using high resolution computed tomography (HRCT). METHODS: parents with confirmed HHT were offered to have their children screened for the mutation identified in their family, and informed consent was obtained. Children carrying the same mutation as their parents underwent HRCT of the chest without contrast. RESULTS: between 2008 and 2015, 99 children were screened for HHT mutations. Mutations were identified in 59 patients, that is 24 HHT1 and 35 HHT2. Radiologic and clinical screening was possible in 52 patients (21 HHT-1 and 31 HHT-2). Among those, PAVM was identified in 13 patients (25%; n = 8 HHT1; n = 5 HHT2), and four of them required embolization therapy. CONCLUSION: This study highlights the usefulness of genetic screening in children with known HHT family. It also suggests that a non-invasive protocol such as HRTC is an efficient approach to detect non-symptomatic lesions that are present early on in children carrying the ENG (HHT1), but also the ACVRL1 mutations (HHT2). Pediatr Pulmonol. 2017;52:642-649. © 2017 Wiley Periodicals, Inc.

Human genetics of common mycobacterial infections.

There is increasing interest in and understanding of the role of human genetic factors controlling susceptibility/resistance to infectious diseases. This is of particular importance for the two most common mycobacterial infections, tuberculosis and leprosy, because this will allow a genetic dissection of antimycobacterial immunity and should open new fields of preventive and therapeutic measures. In this review we will initially discuss various methods of genetic epidemiology that have been and are being developed to identify human genes controlling infectious diseases, and then illustrate the findings obtained in the numerous studies performed in tuberculosis and leprosy. Although the most convincing results were observed for HLA-DR2 and NRAMP1 (or a closely linked gene) in pulmonary tuberculosis and leprosy subtypes and for a 10p13 locus in paucibacillary leprosy, the molecular basis of their effects remains to be established.

Pulmonary thrombosis as the first manifestation of systemic lupus erythematosus in a 14-year-old boy.

We describe the case of a 14-year-old boy who presented with pulmonary embolism and who was subsequently found to have nephrotic syndrome due to lupus membranous nephropathy. He had no other signs of nephrotic syndrome or of systemic lupus erythematosus, such as edema or circulating lupus anticoagulants (antiphospholipid or anticardiolipin antibodies), and no hereditary coagulopathy. This case contributes to our understanding of unusual clinical presentations of systemic lupus erythematosus in children.

Association of IL12RB1 polymorphisms with pulmonary tuberculosis in adults in Morocco.

Five disease-causing genes, including the IL12RB1 gene that encodes the beta 1 chain of the receptor for interleukin (IL)-12 (IL-12R beta 1), are known to be associated with the syndrome of Mendelian susceptibility to mycobacterial diseases. Some IL-12R beta 1-deficient patients present with tuberculosis as the only clinical phenotype. A comprehensive genetic study of IL12RB1 was conducted among 101 Moroccan families, including 157 offspring (age, >15 years) who had culture-positive pulmonary tuberculosis (PTB). The promoter, exons, and flanking intron regions of IL12RB1 in 40 randomly selected patients with PTB were entirely sequenced, leading to the detection of 19 variants (including 10 novel mutations). Blood cells obtained from individuals who were homozygous for any of the 13 most common variants responded to IL-12, indicating that these polymorphisms were not loss-of-function mutations. By use of a family-based study, 2 promoter polymorphisms that were in strong linkage disequilibrium were found to be associated with PTB, especially -2C-->T (odds ratio for CT or TT vs. CC, 2.69 [95% confidence interval, 1.19-6.09]). This result suggests that IL12RB1 polymorphisms might influence the risk of development of PTB in adults.

Association between IFNA genotype and the risk of sarcoidosis.

Sarcoidosis is known to be a systemic granulomatous disorder characterized by a cell-mediated Th1-type inflammatory response. To identify a key genetic factor in the pathogenesis of sarcoidosis, we investigated single nucleotide polymorphisms within 10 candidate genes involved in type 1 immune process ( IFNA17, IFNB, IFNG, IFNGR1, IFNGR2, IL12B, IL12RB1, IL12RB2, ETA-1, and NRAMP1) in an association-based study of 102 Japanese patients with sarcoidosis, 114 with tuberculosis, and 110 control subjects. After correction for multiple testing, an IFNA17 polymorphism (551T-->G) was found to be associated with susceptibility to sarcoidosis (odds ratio 3.27 [95% CI: 1.44-7.46], P=0.004, P(c)=0.04), but not to tuberculosis. We observed no significant associations with the other polymorphisms of the Th1-related genes. We further typed another IFNA polymorphism ( IFNA10 60T-->A) and confirmed two major haplotypes of the IFNA gene, viz., allele 1: IFNA10 [60T]- IFNA17 [551T] and allele 2: IFNA10 [60A]- IFNA17 [551G], in the Japanese population. In healthy subjects, IFNA allele 2, which is over-represented in patients with sarcoidosis, was significantly associated with increased IFN-alpha and IL-12p70 production induced by Sendai virus in vitro. This study suggests that possession of the IFNA allele with higher levels of IFN-alpha significantly increases the risk of sarcoidosis.