Pediatr Pulmonol. 2022 Nov 27. doi: 10.1002/ppul.26259. Online ahead of print.

ABSTRACT

BACKGROUND: MT-RNR1 variants are a well-known cause of aminoglycoside induced hearing loss (AIHL). Individuals with cystic fibrosis routinely receive aminoglycosides and are at high risk of AIHL. However, genetic testing prior to treatment is not routinely performed due to perceived rarity of risk, and cost ineffectiveness with traditional technologies.

AIM: Assess the utility of large-scale screening for AIHL risk in the cystic fibrosis population, using ddPCR, a novel and scalable low-cost molecular technique.

METHODS: Using a clinically validated ddPCR assay, we performed retrospective testing on 122 and prospective testing on 32 individuals with CF for the two most common pathogenic variants associated with aminoglycoside induced hearing loss, MT-RNR1 m.1555A>G and m.1494C>T. Our study screened the largest known cohort of pediatric cases of CF (94/154) for these specific alterations.

RESULTS: We identified two individuals positive for MT-RNR1 m.1555A>G and no positives for m.1494C>T. Of 32 prospective cases, 17 had aminoglycoside exposure. The positive case in our prospective group recently began inhaled tobramycin and denied hearing issues. The clinician adjusted care for both the patient and sibling with CF (not included in cohort) who is presumed positive for m.1555A>G due to the nature of mitochondrial inheritance.

CONCLUSION: Our findings demonstrate the utility of pretreatment screening in the cystic fibrosis population for AIHL risk using ddPCR, a scalable and robust testing methodology at a fraction of the cost as compared to other sequencing-based methods. Therefore, the use of large- scale screening for AIHL risk in the cystic fibrosis community should be re-visited. This article is protected by copyright. All rights reserved.

PMID:36437230 | DOI:10.1002/ppul.26259

Carbohydr Polym. 2023 Feb 1;301(Pt A):120318. doi: 10.1016/j.carbpol.2022.120318. Epub 2022 Nov 11.

ABSTRACT

Burkholderia cenocepacia is an opportunistic pathogen isolated from cystic fibrosis patients where it causes infections that are extremely difficult to treat with antibiotics, and sometimes have a fatal outcome. Biofilm is a virulence trait of B. cenocepacia, and is associated with infection persistence and increased tolerance to antibiotics. In biofilms exopolysaccharides have an important role, conferring mechanical stability and antibiotic tolerance. Two different exopolysaccharides were isolated from B. cenocepacia H111 biofilms: a water-soluble polysaccharide rich in rhamnose and containing an L-Man residue, and a water-insoluble polymer made of glucose, galactose and mannose. In the present work, the product encoded by B. cenocepacia H111 bepA-L gene cluster was identified as the water-insoluble exopolysaccharide, using mutant strains and NMR spectroscopy of the purified polysaccharides. It was also demonstrated that the B. cenocepacia H111 wild type strain produces the water-insoluble exopolysaccharide in pellicles, thus underlining its potential importance in in vivo infections.

PMID:36436859 | DOI:10.1016/j.carbpol.2022.120318

Dig Liver Dis. 2022 Nov 23:S1590-8658(22)00783-6. doi: 10.1016/j.dld.2022.11.006. Online ahead of print.

ABSTRACT

BACKGROUND: low evidence on the dose of enzymatic supplements used in pancreatic enzyme replacement therapy (PERT) is available.

AIM: assessing if fat, protein and starch absorption could be related to the dose of the enzymatic supplement, the intra-patient variability in the dose and macronutrient intake.

METHODS: Four-day food records and 3-day faecal samples were prospectively collected in 69 children with cystic fibrosis. Pearson correlations between enzyme dose and macronutrient absorption, and beta regression models were applied to explain the results.

RESULTS: the supply of protease units per protein intake (PU/g protein) in relation to lipase units per fat intake (LU/g fat) was low and the intra-patient variability in the dose of enzymes was ±1331 LU/g fat. Fat and starch absorption was >90% while for protein it was 81.5%. The coefficient of fat absorption was associated with an interaction between the dose of LU/g fat and its variability among different days. Lipid and protein intake were also determinants of the coefficient of fat absorption.

CONCLUSION: the dose of PERT should be re-adjusted to the amount of dietary fat of every meal (constant LU/g fat) to minimize variability and increase fat absorption. Also, the supply of protease should be increased to prevent from protein malabsorption.

PMID:36435715 | DOI:10.1016/j.dld.2022.11.006

Clin Microbiol Infect. 2022 Nov 23:S1198-743X(22)00586-9. doi: 10.1016/j.cmi.2022.11.014. Online ahead of print.

ABSTRACT

OBJECTIVE: To evaluate the activity of cefiderocol against sequential P. aeruginosa isolates from chronically-infected cystic fibrosis (CF) patients as well as to investigate the potential mechanisms involved in resistance through whole genome sequencing.

METHODS: Three sequential P. aeruginosa isolates from each of 50 chronically-colonized CF patients were studied. MICs for novel and classical antipseudomonal agents were determined by broth microdilution and whole genome sequences (n=150) were obtained to investigate the presence of mutations within a set of chromosomal genes involved in P. aeruginosa antibiotic resistance (n=40) and iron uptake (n=120).

RESULTS: Cefiderocol showed the lowest MIC50/90 values and its susceptibility rate was comparable to other novel antipseudomonal agents. Clinical resistance was documented in 9 isolates from 6 patients. Resistance genes associated with a statistically significant increase in cefiderocol MICs included ampC, pmrAB, galU, fusA1 and those coding the penicillin-binding proteins PBP2 and PBP3. Likewise, mutations within several genes participating in different iron uptake systems were found to be significantly associated with resistance, including genes participating in the pyochelin and pyoverdin biosynthesis and several tonB-dependent receptors. Mutator and small colony variants isolates were also associated with increased cefiderocol MICs.

CONCLUSIONS: Cefiderocol resistance is modulated by a complex mutational resistome, potentially conferring cross-resistance to novel beta-lactam beta-lactamase combinations, as well as an extended list of mutated iron uptake genes. Monitoring the acquisition of mutations in all these genes will be helpful to guide treatments and mitigate the emergence and spread of resistance to this novel antibiotic.

PMID:36435424 | DOI:10.1016/j.cmi.2022.11.014

Curr Microbiol. 2022 Nov 25;80(1):5. doi: 10.1007/s00284-022-03122-x.

ABSTRACT

Lungs of cystic fibrosis patients are often colonized or infected with organisms, such as Pseudomonas aeruginosa and other emerging pathogenic bacteria such as Achromobacter xylosoxidans. Further, it is well established that infections of the cystic fibrosis lung airways are caused by polymicrobial infections, although its composition and diversity may change throughout the patient's life. In the present study, we investigated the effects of N-acetylcysteine (NAC) and amikacin, aztreonam, ciprofloxacin, and tobramycin alone and in combination against single- and dual-species biofilms of P. aeruginosa and A. xylosoxidans, in vitro and in the Caenorhabditis elegans infection model. Results showed that tobramycin and ciprofloxacin were the most effective antibiotics, while aztreonam was the least effective antibiotic against both single- and dual-species biofilms of P. aeruginosa and A. xylosoxidans. However, NAC showed little effect on both single- and dual-species, even with a combination of antibiotics. Increased survival was observed in C. elegans when treated with NAC in combination with tobramycin or ciprofloxacin, compared to no treatment or NAC alone. Tobramycin and ciprofloxacin were found effective in biofilms, but more research is needed to better understand the effects of NAC and antibiotics against single- and dual-species biofilms.

PMID:36434296 | DOI:10.1007/s00284-022-03122-x

Arch Microbiol. 2022 Nov 24;204(12):728. doi: 10.1007/s00203-022-03345-3.

ABSTRACT

Aspergillosis is a mycosis, most commonly affecting the airways. This mycosis can worsen the clinical condition of patients with concurrent lung diseases. We assayed for the presence of serum anti-A. fumigatus IgG in bronchiectasis patients from a tertiary hospital in south Brazil and evaluated the relationship with clinical outcome. Thirty-one patients with bronchiectasis, without cystic fibrosis, were included. Clinical and epidemiological data were collected from all participants. Positive serological tests were detected in 13% (4/31) of the patients. The mortality rate for the year following the assay was, in the seropositive group, 75% (3/4), whereas in the seronegative group, 15% (4/27). An illustrative case is also shown and discussed. Our study highlights the diagnostic challenge and the possible impact of Aspergillus infection on these patients, indicating the necessity of more and larger investigations in the field.

PMID:36434134 | DOI:10.1007/s00203-022-03345-3

Allergol Immunopathol (Madr). 2022 Nov 22;50(S Pt 3):1-9. doi: 10.15586/aei.v50iSP3.764. eCollection 2022.

ABSTRACT

BACKGROUND: Cystic fibrosis (CF) is an inherited autosomal recessive disorder that causes chronic airway disease. In addition to genetic factors, environmental factors may affect the clinical phenotype of CF. In this study, the presence of aeroallergen sensitivity in our patients with CF and its effects on clinical findings are evaluated.

METHODS: In this study, patients included were diagnosed with CF and followed in the Pediatric Respiratory and Allergy Clinic of the Faculty of Medicine, Dokuz Eylul University, Izmir, Turkey. Demographic characteristics, clinical and laboratory findings, skin prick test (SPT) results, and modified Shwachman-Kulczycki (MSK) scores of the patients were evaluated.

RESULTS: We evaluated 51 patients with CF with a median age of 10 (6-18) years. The mean MSK score of the patients was 72.54±11.50, and the mean predictive value of forced expiratory volume (FEV1) in the initial (1st) second was 80.43±19.50. According to SPT, aeroallergen sensitivity was detected in 17 (33.3%) patients. The prevalence of bacterial colonization and bronchiectasis was higher, and MSK scores were lower in Aspergillus fumigatus (AF)-sensitive patients (P ≤ 0.01). However, no similar difference was found in other allergen sensitivities. MSK scores (P = 0.001) and predictive FEV1 values (P = 0.005) of 25 (49%) patients with bacterial colonization were significantly lower than those without colonization.

CONCLUSION: Aeroallergen sensitivity was detected in approximately one-third of CF patients. Although it has been emphasized in studies that environmental factors may have an impact on lung functions and clinical conditions in CF, the effect of allergens other than AF sensitivity may be less important compared to other environmental factors, such as the presence of bacterial colonization.

PMID:36433750 | DOI:10.15586/aei.v50iSP3.764

Magn Reson Med. 2022 Nov 25. doi: 10.1002/mrm.29505. Online ahead of print.

ABSTRACT

PURPOSE: To demonstrate the feasibility of a rapid 3D stack-of-spirals (3D-SoS) imaging acquisition for hyperpolarized 129 Xe ventilation mapping in healthy pediatric participants and pediatric cystic fibrosis (CF) participants, in comparison to conventional Cartesian multislice (2D) gradient-recalled echo (GRE) imaging.

METHODS: The 2D-GRE and 3D-SoS acquisitions were performed in 13 pediatric participants (5 healthy, 8 CF) during separate breath-holds. Images from both sequences were compared on the basis of ventilation defect percent (VDP) and other measures of image similarity. The nadir of transient oxygen saturation (SpO2 ) decline due to xenon breath-holding was measured with pulse oximetry, and expressed as a percent change relative to baseline.

RESULTS: 129 Xe ventilation images were acquired in a breath-hold of 1.2-1.8 s with the 3D-SoS sequence, compared to 6.2-8.8 s for 2D-GRE. Mean ± SD VDP measures for 2D-GRE and 3D-SoS sequences were 5.02 ± 1.06% and 5.28 ± 1.08% in healthy participants, and 18.05 ± 8.26% and 18.75 ± 6.74% in CF participants, respectively. Across all participants, the intraclass correlation coefficient of VDP measures for both sequences was 0.98 (95% confidence interval: 0.94-0.99). The percent change in SpO2 was reduced to -2.1 ± 2.7% from -5.2 ± 3.5% with the shorter 3D-SoS breath-hold.

CONCLUSION: Hyperpolarized 129 Xe ventilation imaging with 3D-SoS yielded images approximately five times faster than conventional 2D-GRE, reducing SpO2 desaturation and improving tolerability of the xenon administration. Analysis of VDP and other measures of image similarity demonstrate excellent agreement between images obtained with both sequences. 3D-SoS holds significant potential for reducing the acquisition time of hyperpolarized 129 Xe MRI, and/or increasing spatial resolution while adhering to clinical breath-hold constraints.

PMID:36433705 | DOI:10.1002/mrm.29505

Int J Mol Sci. 2022 Nov 21;23(22):14483. doi: 10.3390/ijms232214483.

ABSTRACT

A series of new-generation TMA (4,6,4'-trimethyl angelicin) analogues was projected and synthetized in order to ameliorate anti-inflammatory activity, with reduced or absent toxicity. Since the NF-κB transcription factor (TF) plays a critical role in the expression of IL-8 (Interluekin 8), a typical marker of lung inflammation in Cystic Fibrosis (CF), the use of agents able to interfere with the NF-κB pathway represents an interesting therapeutic strategy. Through preliminary EMSA experiments, we identified several new TMA derivatives able to inhibit the NF-κB/DNA complex. The selected active molecules were then analyzed to evaluate the anti-inflammatory effect using both Pseudomonas aeruginosa (PAO1) infection and TNF-alpha stimulus on the CF IB3-1 cell line. It was demonstrated that mainly two TMA analogues, GY971a mesylate salt (6-p-minophenyl-4,4'-dimethyl-angelicin) and GY964 (4-phenyl-6,4'-dimethyl-angelicin), were able to decrease the IL-8 gene expression. At the same time, these molecules were found to have no pro-apoptotic, mutagenic and phototoxic effects, facilitating our decision to test the efficacy in vivo by using a mouse model of acute P. aeruginosa lung infection. The anti-inflammatory effect of GY971a was confirmed in vivo; this derivative was able to deeply decrease the total number of inflammatory cells, the neutrophil count and the cytokine/chemokine profile in the P. aeruginosa acute infection model, without evident toxicity. Considering all the obtained and reported in vitro and in vivo pre-clinical results, GY971a seems to have interesting anti-inflammatory effects, modulating the NF-κB pathway, as well as the starting lead compound TMA, but without side effects.

PMID:36430961 | DOI:10.3390/ijms232214483

Int J Mol Sci. 2022 Nov 19;23(22):14399. doi: 10.3390/ijms232214399.

ABSTRACT

Dry eye disease (DED) is a multifactorial disease with an incidence of approximately 50% worldwide. DED seriously affects quality of life and work. The prevalence of environmental DED (eDED) ranges from 35 to 48%. Conjunctival fluid secretion dysfunction may be one of the major causes of DED. Notably, the Cl- flux corresponds to the conjunctival fluid secretion and could be affected by ATP. Both the cystic fibrosis transmembrane conductance regulator (CFTR) and the Ca2+-activated Cl- channel (CaCC) are Cl- channels involved in epithelial fluid secretion. Conjunctival fluid secretion could be increased by activating P2Y2R (an ATP receptor) in DED. However, the role of the CaCC and CFTR channels regulated by P2Y2R in eDED remains unclear. In this study, we established a rabbit eDED model using a controlled drying system. A Ussing chamber was used to perform a conjunctival short-circuit current induced by ATP to evaluate the reactivity of the ion channels to the ATP. Our results revealed that eDED accompanied by conjunctival fluid secretion impairment was caused by a P2Y2R dysfunction, which is related to CaCC-CFTR signaling in the conjunctiva epithelium. Notably, the coupling effect of the ATP-induced CaCC-CFTR activation and intracellular Ca2+ may represent a promising therapeutic target for treating eDED.

PMID:36430877 | DOI:10.3390/ijms232214399

Int J Mol Sci. 2022 Nov 17;23(22):14205. doi: 10.3390/ijms232214205.

ABSTRACT

Although cystic fibrosis (CF) is recognized as a monogenic disease, due to variants within the CFTR (Cystic Fibrosis Transmembrane Regulator) gene, an extreme clinical heterogeneity is described among people with CF (pwCF). Apart from the exocrine pancreatic status, most studies agree that there is little association between CFTR variants and disease phenotypes. Environmental factors have been shown to contribute to this heterogeneity, accounting for almost 50% of the variability of the lung function of pwCF. Nevertheless, pwCF with similar CFTR variants and sharing the same environment (such as in siblings) may have highly variable clinical manifestations not explained by CFTR variants, and only partly explained by environmental factors. It is recognized that genetic variants located outside the CFTR locus, named "modifier genes", influence the clinical expression of the disease. This short review discusses the latest studies that have described modifier factors associated with the various CF phenotypes as well as the response to the recent CFTR modulator therapies.

PMID:36430680 | DOI:10.3390/ijms232214205

Int J Environ Res Public Health. 2022 Nov 16;19(22):15055. doi: 10.3390/ijerph192215055.

ABSTRACT

There is an increasing interest in father-child interactions and their effects. Due to the rising number of working mothers, marital interruptions, divorces, and child custody arrangements, paternal duties and the relevance of fathering continue to be re-evaluated. As there are rising expectations for men to undertake more childcare and household responsibilities, it was hypothesized that the presence of a disabled or chronically ill child would have a significant impact on the couple's future family situation, marital conduct due to paternal dissatisfaction, and increased stress levels. Therefore, the purpose of this study was to examine paternal intimacy problems, stress levels, and couple satisfaction inside families that have children with cystic fibrosis. The study followed a cross-sectional design with five questionnaires that were answered by a total of 107 fathers of children with cystic fibrosis from the "cases" group as the reference group, and 124 fathers of healthy children from the "control" group. The statistically significant findings of the current study show that men who were taking care of their child with mucoviscidosis engaged less frequently in sexual activity. A significantly higher number of these respondents were smokers. A higher proportion of them reported marital distress (OR = 2.54) and inhibited sexual desire (OR = 2.02), all in association with a higher number of men taking psychiatric medication (7.5% vs. 1.6%). More than 40% of all respondents declared high levels of general stress and parenting distress, while the most frequently used coping mechanism for stress was avoidance-oriented (45.8% vs. 25.8%). Other important findings were the high levels of dissatisfaction and lower levels of marital quality on the SII scale, equivalent to the intimacy problems on the MIQ scale. It is likely that paternal stress is higher when parenting children with cystic fibrosis, and the lack of intervention in this vulnerable group seem to be associated with intimacy problems, couple dissatisfaction, and maladaptive coping mechanisms. It is recommended that these concerns should not only be raised for the mothers of children with mucoviscidosis, but also for the child's father or the male caretaker partner since they might experience the same problems as the opposite gender.

PMID:36429771 | DOI:10.3390/ijerph192215055

Diagnostics (Basel). 2022 Nov 21;12(11):2893. doi: 10.3390/diagnostics12112893.

ABSTRACT

Cystic fibrosis (CF) is the most common life-limiting genetic disorder in European descent populations. It is caused by pathogenic variants in the CFTR gene, and inheritance is autosomal recessive. This study provides an up-to-date, comprehensive estimation of the distribution of CFTR pathogenic variants in Latvia and their phenotypic characteristics. It also reports the first results of the CF newborn screening programme following its implementation in 2019. We analysed the clinical and molecular data of CF patients treated at the only tertiary hospital in Latvia providing specialised healthcare for the disorder. Between 1997 and 2022, 66 CF patients from 62 families were diagnosed based on symptoms or a molecular confirmation (six patients were diagnosed through the CF newborn screening programme). F508del was identified in 70.5% of all CF chromosomes. Known variants were identified in more than one family: dele2,3, R1006H, L1335P, W57R, R553X, 2143delT and 3849+10kb C>T (legacy names used). Furthermore, two novel variants were identified, namely, c.503C>A p.(Ser168Ter) and c.(743+1_744-1)_(1584+1_1585-1)del p.(?). The available follow-up results indicated that Latvian CF patients demonstrated similar tendencies to CF patients worldwide. The oldest age at diagnosis prior to the implementation of the CF newborn screening programme was 14 years. We provide here, for the first time, a comprehensive description of Latvian CF patients. An improvement in the healthcare of CF patients over time, including access to diagnosis, is evident. Two novel CF-causing variants are reported, and F508del is the most frequently occurring variant in the population, thus suggesting that F508del screening should be followed by the testing of the full CFTR gene.

PMID:36428953 | DOI:10.3390/diagnostics12112893

Pediatr Pulmonol. 2022 Nov 25. doi: 10.1002/ppul.26227. Online ahead of print.

ABSTRACT

The field of rare and diffuse pediatric lung disease is experiencing rapid progress as diagnostic and therapeutic options continue to expand. In this annual review, we discuss manuscripts published in Pediatric Pulmonology in 2021 in (1) children's interstitial and diffuse lung disease, (2) congenital airway and lung malformations, and (3) non-cystic fibrosis bronchiectasis including primary ciliary dyskinesia. These include case reports, descriptive cohorts, trials of therapies, animal model studies, and review articles. The results are put into the context of other literature in the field. Each furthers the field in important ways, while also highlighting the continued need for further studies. This article is protected by copyright. All rights reserved.

PMID:36426677 | DOI:10.1002/ppul.26227

Biophys Rep (N Y). 2022 Oct 19;2(4):100083. doi: 10.1016/j.bpr.2022.100083. eCollection 2022 Dec 14.

ABSTRACT

The closing of the gated ion channel in the cystic fibrosis transmembrane conductance regulator can be categorized as nonpermissive to reopening, which involves the unbinding of ADP or ATP, or permissive, which does not. Identifying the type of closing is of interest as interactions with nucleotides can be affected in mutants or by introducing agonists. However, all closings are electrically silent and difficult to differentiate. For single-channel patch-clamp traces, we show that the type of the closing can be accurately determined by an inference algorithm implemented on a factor graph, which we demonstrate using both simulated and lab-obtained patch-clamp traces.

PMID:36425670 | PMC:PMC9680790 | DOI:10.1016/j.bpr.2022.100083

Int J Chron Obstruct Pulmon Dis. 2022 Nov 17;17:2919-2929. doi: 10.2147/COPD.S386965. eCollection 2022.

ABSTRACT

PURPOSE: Whether the empirical use of anti-pseudomonal antibiotics actually improves patient outcomes is unclear. Hence, we aimed to determine whether empirical anti-pseudomonal antibiotics are better than anti-pseudomonal antibiotics in treating patients with recurrent lower respiratory tract infections (LRTIs).

PATIENTS AND METHODS: We extracted data from the Japanese nationwide database of the Real World Data Co., Ltd. Our target population was patients with LRTIs, defined as chronic obstructive pulmonary disease exacerbation and pneumonia. We included patients aged ≥40 years who were admitted for lower respiratory tract infections ≥2 times within 90 days. We excluded patients who had an event (death or transfer) within 24 h after admission. We ran a frailty model adjusted for the following confounding factors: number of recurrences, age, body mass index, activities of daily living, Hugh-Johns classification, altered mental status, oxygen use on admission, blood urea nitrogen, and systemic steroid use.

RESULTS: We included 893 patients with 1362 observations of recurrent LRTIs. There were 897 (66%) observations in the non-anti-pseudomonal antibiotic group and 465 (34%) in the anti-pseudomonal group; the numbers of in-hospital deaths were 86/897 (10%) and 63/465 (14%), respectively. Our frailty model yielded an adjusted hazard ratio (HR) (anti-pseudomonal group/non-anti-pseudomonal group) of 1.49 (95% confidence interval, 1.03-2.14).

CONCLUSION: The empirical use of anti-pseudomonal antibiotics was associated with a higher HR of in-hospital mortality than the use of non-anti-pseudomonal antibiotics. Physicians might need to consider limiting the prescription of anti-pseudomonal antibiotics based on background factors such as the patient's baseline function and disease severity. Further studies are needed to evaluate the causal relationship between empirical anti-pseudomonal antibiotics and mortality, and identify specific patient population who benefit from empirical anti-pseudomonal antibiotics.

PMID:36419949 | PMC:PMC9677644 | DOI:10.2147/COPD.S386965

Eur Respir J. 2022 Nov 24;60(5):2201748. doi: 10.1183/13993003.01748-2022. Print 2022 Nov.

NO ABSTRACT

PMID:36423920 | DOI:10.1183/13993003.01748-2022

Eur Respir J. 2022 Nov 24:2201341. doi: 10.1183/13993003.01341-2022. Online ahead of print.

NO ABSTRACT

PMID:36423906 | DOI:10.1183/13993003.01341-2022

Respir Med. 2022 Nov 17;205:107056. doi: 10.1016/j.rmed.2022.107056. Online ahead of print.

NO ABSTRACT

PMID:36423458 | DOI:10.1016/j.rmed.2022.107056

Cochrane Database Syst Rev. 2022 Nov 24;11:CD013233. doi: 10.1002/14651858.CD013233.pub2.

ABSTRACT

BACKGROUND: Assisted reproductive technology (ART) has allowed couples with a family history of a monogenic genetic disease, or a disease-carrying gene, to reduce the chance of them having a child with the genetic disorder. This is achieved by genetically testing the embryos using an advanced process called preimplantation genetic testing for monogenic or single gene disorders (PGT-M), such as Huntington's disease or cystic fibrosis. This current terminology (PGT-M) has replaced the formerly-known preimplantation genetic diagnosis (PGD). During PGT-M, one or more embryo cells are biopsied and analysed for genetic or chromosomal anomalies before transferring the embryos to the endometrial cavity. Biopsy for PGT-M can be performed at day 3 of cleavage-stage embryo development when the embryo is at the six- to the eight-cell stage, with either one or two blastomeres being removed for analysis. Biopsy for PGT-M can also be performed on day 5 of the blastocyst stage of embryo development when the embryo has 80 to 100 cells, with five to six cells being removed for analysis. Day 5 biopsy has taken over from day 3 biopsy as the most widely-used biopsy technique; however, there is a lack of summarised evidence from randomised controlled trials (RCTs) that assesses the effectiveness and safety of day 5 biopsy compared to day 3 biopsy. Since biopsy is an invasive process, whether it is carried out at day 3 or day 5 of embryo development may have different impacts on further development, implantation, pregnancy, live birth and perinatal outcomes.

OBJECTIVES: To assess the benefits and harms of day 5 embryo biopsy, in comparison to day 3 biopsy, in PGT-M in women undergoing in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI) cycles.

SEARCH METHODS: We searched the following electronic bibliographic databases in December 2021 to identify relevant RCTs: the Cochrane Gynaecology and Fertility Group (CGFG) Specialised Trials Register; CENTRAL, MEDLINE, Embase and PsycINFO. We also handsearched grey literature, such as trial registers, relevant journals, reference lists, Google Scholar, and published conference abstracts.

SELECTION CRITERIA: Eligible RCTs compared day 5 versus day 3 embryo biopsy for PGT-M. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures recommended by Cochrane. The primary review outcomes were live births and miscarriages. We calculated outcomes per woman/couple randomised and reported odds ratios (ORs) with 95% confidence intervals (CIs).

MAIN RESULTS: We included one RCT involving 20 women. The evidence was of very low certainty; the main limitations of the study were serious risk of bias due to lack of blinding of study personnel, and imprecision. We are uncertain whether day 5 embryo biopsy compared to day 3 biopsy has an effect on live births (OR 1.50, 95% CI 0.26 to 8.82; 1 RCT, 20 women; very low-certainty evidence). The evidence suggests that if the chance of live birth following day 3 biopsy was assumed to be 40%, then the chance with day 5 biopsy is between 15% and 85%. It is also uncertain whether day 5 embryo biopsy compared to day 3 biopsy has an effect on miscarriages (OR 1.00, 95% CI 0.05 to 18.57; 1 RCT, 20 women; very low-certainty evidence). We are uncertain whether day 5 embryo biopsy compared to day 3 biopsy has an effect on other secondary outcome measures, including viable intrauterine pregnancies (OR 2.25, 95% CI 0.38 to 13.47; 1 RCT, 20 women; very low-certainty evidence), ectopic pregnancies (OR 0.16, 95% CI 0.01 to 3.85; 1 RCT, 20 women; very low-certainty evidence), stillbirths (OR not estimable as no events in either group; 1 RCT, 20 women; very low-certainty evidence) or termination of pregnancies (OR 3.32, 95% CI 0.12 to 91.60; 1 RCT, 20 women; very low-certainty evidence). No studies reported on gestational age at birth, birthweight, neonatal mortality and major congenital anomaly.

AUTHORS' CONCLUSIONS: We are uncertain if there is a difference in live births and miscarriages, viable intrauterine pregnancies, ectopic pregnancies, stillbirths or termination of pregnancies between day 5 and day 3 embryo biopsy for PGT-M. There was insufficient evidence to draw any conclusions regarding other adverse outcomes. The results should be interpreted with caution, as the evidence was of very low certainty due to limited studies, high risk of bias in the included study, and an overall low level of precision.

PMID:36423200 | DOI:10.1002/14651858.CD013233.pub2