Practical delta check limits for tumour markers in different clinical settings.

OBJECTIVES: Few studies have reported on delta checks for tumour markers, even though these markers are often evaluated serially. Therefore, this study aimed to establish a practical delta check limit in different clinical settings for five tumour markers: alpha-fetoprotein, cancer antigen 19-9, cancer antigen 125, carcinoembryonic antigen, and prostate-specific antigen. METHODS: Pairs of patients' results (current and previous) for five tumour markers between 2020 and 2021 were retrospectively collected from three university hospitals. The data were classified into three subgroups, namely: health check-up recipient (subgroup H), outpatient (subgroup O), and inpatient (subgroup I) clinics. The check limits of delta percent change (DPC), absolute DPC (absDPC), and reference change value (RCV) for each test were determined using the development set (the first 18 months, n=179,929) and then validated and simulated by applying the validation set (the last 6 months, n=66,332). RESULTS: The check limits of DPC and absDPC for most tests varied significantly among the subgroups. Likewise, the proportions of samples requiring further evaluation, calculated by excluding samples with both current and previous results within the reference intervals, were 0.2-2.9% (lower limit of DPC), 0.2-2.7% (upper limit of DPC), 0.3-5.6% (absDPC), and 0.8-35.3% (RCV99.9%). Furthermore, high negative predictive values >0.99 were observed in all subgroups in the in silico simulation. CONCLUSIONS: Using real-world data, we found that DPC was the most appropriate delta-check method for tumour markers. Moreover, Delta-check limits for tumour markers should be applied based on clinical settings.

Distinct molecular evolution of influenza H3N2 strains in the 2016/17 season and its implications for vaccine effectiveness.

Influenza virus is a respiratory pathogen that causes seasonal epidemics by resulting in a considerable number of influenza-like illness (ILI) patients. During the 2016/17 season, ILI rates increased unusually earlier and higher than previous seasons in Korea, and most viral isolates were subtyped as H3N2 strains. Notably, the hemagglutinin (HA) of most Korean H3N2 strains retained newly introduced lysine signatures in HA antigenic sites A and D, compared with that of clade 3C.2a vaccine virus, which affected antigenic distances to the standard vaccine antisera in a hemagglutination inhibition assay. The neuraminidase (NA) of Korean H3N2 strains also harbored amino acid mutations. However, neither consistent amino acid mutations nor common phylogenetic clustering patterns were observed. These suggest that Korean H3N2 strains of the 2016/17 season might be distantly related with the vaccine virus both in genotypic and phenotypic classifications, which would adversely affect vaccine effectiveness.

Serial changes in serum procalcitonin, interleukin 6, and C-reactive protein levels according to non-specific surgical stimulation.

BACKGROUND: The aim of this study is to investigate useful perioperative monitoring markers by comparing serial levels of serum procalcitonin (PCT), interleukin 6 (IL-6), and C-reactive protein (CRP) in routine surgical circumstances. METHODS: In 285 surgeries of 277 patients, blood samples were obtained serially, at least three times per patient: within 48 h before surgery, 0-6 h after surgery (post-OP1), >6-28 h after surgery (post-OP2), and/or later (post-OP3). PCT, IL-6, and CRP were measured. Their demographic, operative, laboratory, and clinical data were collected retrospectively. RESULTS: The systemic inflammatory response syndrome (SIRS) (n=39) and sepsis (n=11) groups showed higher post-operative values than the non-SIRS group (n=233). Their maximum significant median levels were 8.96 vs. 0.21 µg/L for post-OP2 PCT, 743.1 vs. 85.8 ng/L for post-OP1 IL-6, and 103.4 vs. 49.0 mg/L for post-OP2 CRP. Among non-SIRS patients, 12 patients developed undesirable post-operative events, including secondary surgery and death. The highest area under receiver operator characteristic curves was 0.92 at post-OP1 PCT (cut-off, 0.1 µg/L; sensitivity, 91.7%; specificity, 78.7%), and the next highest was 0.84 at post-OP1 IL-6 (cut-off, 359 ng/L; sensitivity, 66.7%; specificity, 91.9%). All biomarkers were increased by non-specific surgical stimuli; however, post-OP1/post-OP2 PCT were <1.0 µg/L (90th percentile) except major abdominal surgeries. CONCLUSIONS: Post-OP1 PCT measurement may be useful as a post-operative monitoring marker for the following reasons: pre-operative values less than the cut-off regardless of pre-operative state (age, malignancy, and American Society of Anesthesiologists class); minimal influence from surgical stimulus; and prediction of post-operative undesirable events.

A rigorous in silico genomic interrogation at 1p13.3 reveals 16 autosomal dominant candidate genes in syndromic neurodevelopmental disorders.

Genome-wide chromosomal microarray is extensively used to detect copy number variations (CNVs), which can diagnose microdeletion and microduplication syndromes. These small unbalanced chromosomal structural rearrangements ranging from 1 kb to 10 Mb comprise up to 15% of human mutations leading to monogenic or contiguous genomic disorders. Albeit rare, CNVs at 1p13.3 cause a variety of neurodevelopmental disorders (NDDs) including development delay (DD), intellectual disability (ID), autism, epilepsy, and craniofacial anomalies (CFA). Most of the 1p13.3 CNV cases reported in the pre-microarray era encompassed a large number of genes and lacked the demarcating genomic coordinates, hampering the discovery of positional candidate genes within the boundaries. In this study, we present four subjects with 1p13.3 microdeletions displaying DD, ID, autism, epilepsy, and CFA. In silico comparative genomic mapping with three previously reported subjects with CNVs and 22 unreported DECIPHER CNV cases has resulted in the identification of four different sub-genomic loci harboring five positional candidate genes for DD, ID, and CFA at 1p13.3. Most of these genes have pathogenic variants reported, and their interacting genes are involved in NDDs. RT-qPCR in various human tissues revealed a high expression pattern in the brain and fetal brain, supporting their functional roles in NDDs. Interrogation of variant databases and interacting protein partners led to the identification of another set of 11 potential candidate genes, which might have been dysregulated by the position effect of these CNVs at 1p13.3. Our studies define 1p13.3 as a genomic region harboring 16 NDD candidate genes and underscore the critical roles of small CNVs in in silico comparative genomic mapping for disease gene discovery. Our candidate genes will help accelerate the isolation of pathogenic heterozygous variants from exome/genome sequencing (ES/GS) databases.

Molecular cytogenetic and clinical characterization of a patient with a 5.6-Mb deletion in 7p15 including HOXA cluster.

Here, we describe the clinical features of a boy with a 5.6-Mb deletion at chromosome 7p15.1-p15.3. He has mild facial anomalies, hand-foot abnormalities, hypospadias, congenital heart defects, and supernumerary nipples. This deletion was detected by array comparative genomic hybridization and verified by fluorescence in situ hybridization using BACs selected from the USCS genome browser. This deletion was not found in subsequent FISH analysis of the parental chromosomes. The deleted region contains several genes, including contiguous developmental genes on the HOXA cluster, which play a role in regulating aspects of morphogenesis during normal embryonic development. The patient's limb and urogenital features were similar to those observed in hand-foot-genital syndrome, which is caused by haploinsufficiency of HOXA13, whereas the congenital heart defect may reflect the deletion of HOXA3. We hypothesized that many clinical features of the patient were due to combined haploinsufficiency of the HOXA cluster. Our study also demonstrates the clinical usefulness of a molecular cytogenetic tool that is capable of detecting imbalances in the genome.

Significance of serum neuron-specific enolase in transient global amnesia.

Neuron-specific enolase (NSE) is a glycolytic enzyme, which is associated with neuronal cell dysfunction in the brain. This study evaluated the role of serum NSE levels of patients with transient global amnesia (TGA). In addition, the relationship between serum NSE levels and the clinical features of TGA was explored. Forty-eight patients with TGA were prospectively included, and their serum NSE levels were measured. We investigated serum NSE levels in patients with TGA. In addition, we analyzed the differences in clinical characteristics between patients with elevated and normal serum NSE levels. Of the 48 patients with TGA, 16 patients (33.3%) had elevated serum NSE levels (25.0 ± 11.5 ng/mL), whereas 32 patients (66.7%) showed normal serum NSE levels (12.8 ± 2.1 ng/mL). The patients with elevated serum NSE levels exhibited higher levels of cognitive impairment than those with normal serum NSE levels (4/16 vs. 1/32, p = 0.036). The serum NSE levels showed a relatively high discrimination (AUC 0.684) between patients with and without cognitive impairment, with 80.0% sensitivity and 74.4% specificity at a cut-off value 17.3 ng/mL. A third of all patients with TGA carry elevated serum NSE levels, which suggests that the neuronal cell dysfunction could be associated with TGA pathogenesis. In addition, it might be correlated with cognitive impairment.

Compound Heterozygous PIGT Mutations in Multiple Congenital Anomalies-Hypotonia-Seizures Syndrome: First Case in Korea and Characterization by Persistent Hypophosphatasia.

Mutations of phosphatidylinositol glycan biosynthesis class T (PIGT), which encodes a subunit of the glycosylphosphatidylinositol (GPI) transamidase complex, can lead to multiple anomalies, including seizures, intellectual disabilities, facial dysmorphism, and various congenital malformations. We performed whole-exome sequencing in a patient with seizures, intellectual disabilities, truncal ataxia, facial dysmorphism, and persistent hypophosphatasia without rickets or bone mineralization defects, and identified two heterozygous mutations in PIGT, c.250G>T (p.Glu84*) and c.1582G>A (p.Val528Met). GPI-linked protein analyses found no abnormalities. Although the patient's hypophosphatasia persists, no skeletal, urological, or dental abnormalities were found. The seizures disappeared after administering antiepileptic drugs. PIGT mutations should be considered in patients with multiple congenital symptoms and persistent hypophosphatasia.

Pharmacokinetics and Monte Carlo Simulation of Meropenem in Critically Ill Adult Patients Receiving Extracorporeal Membrane Oxygenation.

Objectives: There have been few clinical studies of ECMO-related alterations of the PK of meropenem and conflicting results were reported. This study investigated the pharmacokinetics (PK) of meropenem in critically ill adult patients receiving extracorporeal membrane oxygenation (ECMO) and used Monte Carlo simulations to determine appropriate dosage regimens. Methods: After a single 0.5 or 1 g dose of meropenem, 7 blood samples were drawn. A population PK model was developed using nonlinear mixed-effects modeling. The probability of target attainment was evaluated using Monte Carlo simulation. The following treatment targets were evaluated: the cumulative percentage of time during which the free drug concentration exceeds the minimum inhibitory concentration of at least 40% (40% fT>MIC), 100% fT>MIC, and 100% fT>4xMIC. Results: Meropenem PK were adequately described by a two-compartment model, in which creatinine clearance and ECMO flow rate were significant covariates of total clearance and central volume of distribution, respectively. The Monte Carlo simulation predicted appropriate meropenem dosage regimens. For a patient with a creatinine clearance of 50-130 ml/min, standard regimen of 1 g q8h by i. v. infusion over 0.5 h was optimal when a MIC was 4 mg/L and a target was 40% fT>MIC. However, the standard regimen did not attain more aggressive target of 100% fT>MIC or 100% fT>4xMIC. Conclusion: The population PK model of meropenem for patients on ECMO was successfully developed with a two-compartment model. ECMO patients exhibit similar PK with patients without ECMO. If more aggressive targets than 40% fT>MIC are adopted, dose increase may be needed.

Unilateral diffuse white matter involvement in a patient with atypical FMR1 mutation.

A 62-year-old man without relevant medical history visited our emergency department with seizure. His brain MRI revealed diffuse high signal intensity in the white matter with some cortical involvement in the dorsolateral prefrontal area and middle frontal gyrus on FLAIR sequence, which were only confined to the left hemisphere. In his whole exome sequencing, a hemizygous variant, NM_001185081.1:c.1216C>T, was detected on FMR1 gene of Xq27.3, which creates a stop codon at codon 406 in exon 13. The variant is classified as pathogenic according to the recommendation of ACMG/AMP guideline. This is the first case report of the patient presenting with seizure, who had a pathogenic variant on FMR1 gene with diffuse cerebral white matter involvements in the unilateral hemisphere.

Identification of a novel HLA-DQB1*05 variant allele, HLA-DQB1*05:247 by next-generation sequencing.

The new allele, HLA-DQB1*05:247 differs from HLA-DQB1*05:02:01:01 by one nucleotide substitution at codon 35.

First Korean Case of Coffin-Siris Syndrome with a Novel Frameshift ARID1B Mutation.

Coffin-Siris Syndrome (CSS) is a rare neurodevelopmental disorder characterized by intellectual disability, coarse facial features, hypoplastic digits/nails, and hypertrichosis. The genes causative of CSS mainly encode the SWI/SNF complex, which contributes to chromatin remodeling and regulates the access of transcriptional factors to specific gene sites. While ARID1B mutations account for a third of all CSS cases, the condition's phenotypic features vary widely. We document the case of a girl with CSS who presented with a variant facial appearance, global developmental delay with speech impairment, agenesis of the corpus callosum, funnel chest, and bilateral renal stones without hypertrichosis or hypoplasia of the fifth fingernail. Genetic analysis revealed that the patient had a novel heterozygous frameshift mutation c.2201dupG (p.Ser736Ilefs*27) on the ARID1B gene.

Identification of a novel HLA-B*40 variant allele, B*40:405 by next-generation sequencing.

The new allele, HLA-B*40:405 differs from B*40:02:01:01 by one nucleotide substitution at codon 304.

Detection of human metapneumovirus by direct antigen test and shell vial cultures using immunofluorescent antibody staining.

Human metapneumovirus (hMPV) has emerged as an important etiologic agent of upper and lower respiratory tract infections, especially in young children. Although rapid and simple diagnostic methods for hMPV are needed in clinical laboratories, routine diagnostic tests are not readily available. The purpose of this study was to evaluate a commercial anti-hMPV monoclonal antibody for a direct antigen test and a shell vial culture of hMPV. In the pilot study, 15 nasopharyngeal aspirates from 15 children with acute respiratory tract infections positive for hMPV by reverse transcriptase polymerase chain reaction (RT-PCR) were tested. Both direct antigen test and shell vial culture detected hMPV in 14 of 15 (93.3%) nasopharyngeal aspirates at initial diagnosis. In the larger group prospective study, nasopharyngeal aspirates from 92 children with acute respiratory tract infections were tested for hMPV with RT-PCR, direct antigen test, and shell vial culture. Both direct antigen test and shell vial culture showed positivity for 4 out of 5 specimens positive by RT-PCR. These findings indicate that direct antigen test and shell vial culture would be reliable and timely methods for the diagnosis of hMPV infection in clinical laboratories.

Recommendation of the use of myeloblast percentage among non-erythroid cells instead of percentage among total nucleated cells for therapeutic response assessment in acute erythroid leukemia.

The diagnostic criteria of acute erythroid leukemias (AEL) has been revised by WHO in 2001. The National Cancer Institute (NCI) published a set of standardized diagnostic and response criteria for acute myeloid leukemia in 1990, which was revised in 2003. The aim of the present study was to establish the best criteria for therapeutic response assessment in the newly classified AEL and evaluate patient outcomes. Fifty-two patients with AEL as defined by the new WHO criteria were evaluated in this study. The following seven indices for therapeutic response assessment were evaluated: (i) NCI criteria (myeloblast percentage among total nucleated cells (TNC) and cellularity); (ii) myeloblast percentage among non-erythroid cells (NEC) and cellularity; (iii) erythroid series percentage among TNC; (iv) pronormoblast percentage among erythroid cells; (v) ratio of pronormoblasts and blasts; (vi) maturation arrest index; and (vii) disappearance of erythroid dysplasia. Complete remission (CR) patients with <5% of myeloblast/NEC (NEC-CR) showed significantly longer overall survival periods (mean 55.8 months) compared to CR patients with >5% myeloblast/NEC (mean 11.7 months, P = 0.006). NEC-CR patients also had longer event-free survival (median 16.4 months) compared to patients with >5% and <20% of myeloblast/NEC (median 6.2 months) (P = 0.044). The other indices for therapeutic response assessment are not significant for predictability of relapse and outcomes. Therefore, we recommend that the myeloblast percentage among NEC be used instead of myeloblast percentage among TNC for therapeutic response assessment in AEL.