Hb Kalundborg [ß79(EF3)Asp→Glu; HBB: c.240C>a], a Possible Low-affinity Hemoglobin Variant Detected during Hb A1c Measurement.

A previously unknown hemoglobin (Hb) variant was detected during measurement of glycosylated Hb (Hb A1c) after the introduction of a new high performance liquid chromatography (HPLC) apparatus. Subsequent DNA sequencing revealed a heterozygous single nucleotide substitution at codon 79 (C>A) on the ß-globin gene changing an amino acid [ß79(EF3)Asp→Glu; HBB: c.240C>A]. The new Hb variant was named Hb Kalundborg after the place of origin of the proband. Heterozygosity for this mutation appears to have no clinical significance in itself except for a possibly slightly lower oxygen affinity. However, it interferes with Hb A1c measurement by HPLC, causing a falsely high Hb A1c concentration when using the G11 apparatus with clinical implications possibly to follow.

Comparison of 16 Serological SARS-CoV-2 Immunoassays in 16 Clinical Laboratories.

Serological assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are needed to support clinical diagnosis and epidemiological investigations. Recently, assays for large-scale detection of total antibodies (Ab), immunoglobulin G (IgG), and IgM against SARS-CoV-2 antigens have been developed, but there are limited data on the diagnostic accuracy of these assays. This study was a Danish national collaboration and evaluated 15 commercial and one in-house anti-SARS-CoV-2 assays in 16 laboratories. Sensitivity was evaluated using 150 samples from individuals with asymptomatic, mild, or moderate COVID-19, nonhospitalized or hospitalized, confirmed by nucleic acid amplification tests (NAAT); samples were collected 13 to 73 days either from symptom onset or from positive NAAT (patients without symptoms). Specificity and cross-reactivity were evaluated in samples collected prior to the SARS-CoV-2 epidemic from >586 blood donors and patients with autoimmune diseases, cytomegalovirus or Epstein-Barr virus infections, and acute viral infections. A specificity of ≥99% was achieved by all total-Ab and IgG assays except one, DiaSorin Liaison XL IgG (97.2%). Sensitivities in descending order were Wantai ELISA total Ab (96.7%), CUH-NOVO in-house ELISA total Ab (96.0%), Ortho Vitros total Ab (95.3%), YHLO iFlash IgG (94.0%), Ortho Vitros IgG (93.3%), Siemens Atellica total Ab (93.2%), Roche Elecsys total Ab (92.7%), Abbott Architect IgG (90.0%), Abbott Alinity IgG (median 88.0%), DiaSorin Liaison XL IgG (median 84.6%), Siemens Vista total Ab (81.0%), Euroimmun/ELISA IgG (78.0%), and Snibe Maglumi IgG (median 78.0%). However, confidence intervals overlapped for several assays. The IgM results were variable, with the Wantai IgM ELISA showing the highest sensitivity (82.7%) and specificity (99%). The rate of seropositivity increased with time from symptom onset and symptom severity.

Environmental tobacco smoke exposure during pregnancy has limited effect on infant birthweight and umbilical vein endothelial nitric oxide synthase.

INTRODUCTION: Women who smoke, deliver significantly smaller infants. These infants have reduced levels of the vasodilator endothelial nitric oxide synthase (eNOS) levels in the umbilical vessels, which may reduce fetal growth. Serum cotinine, the degradation product of nicotine, can be used to determine the level of tobacco exposure. Newborns of environmental smokers are suggested to be smaller and shorter in weight, length, and head circumference. eNOS levels have not yet been studied in these infants. We investigated the existence of a relation between maternal environmental tobacco smoke exposure, eNOS activity, concentration, and birthweight. MATERIAL AND METHODS: We included 263 healthy singleton pregnancies categorized into three groups according to measured cotinine levels: 175 nonsmokers, 38 smokers, and 50 environmental smokers. Cotinine was quantified by mass spectrometry with a detection limit of .2 ng/mL; eNOS activity and concentration were measured in endothelial cells (ECs) of the umbilical vein. RESULTS: Infants born to environmental smokers had similar weights to infants born to nonsmokers (47 g heavier, P = .48). Cotinine concentrations were .06/.09/.12 ng/mL (quartiles) in infants born to nonsmokers, .27/.37/.81 ng/mL in infants born to women exposed to environmental tobacco smoke, and 43.0/63.8/108.1 ng/mL in infants born to smokers. The eNOS concentration was 1.65 ± .92 ng/106 ECs (mean ± SD) in nonsmokers and 1.71 ± 1.00 ng/106 ECs in environmental smokers. The eNOS activity was 52.0 ± 20.6 pmol l-citrulline/min/106 ECs in nonsmokers and 48.7 ± 19.8 pmol l-citrulline/min/106 ECs in environmental smokers. CONCLUSIONS: Infants born to environmental smokers, as judged by umbilical serum cotinine levels close to .2 ng/mL, are not associated with lower birthweight or reduced eNOS activity, or concentration in the fetal vascular bed.

The smartphone camera as a potential method for transcutaneous bilirubin measurement.

BACKGROUND: Hyperbilirubinemia is a common problem in neonates that can progress into kernicterus. Suspected neonatal hyperbilirubinemia is a common reason for contact with the healthcare system. The severity and management of jaundice are determined based on estimated bilirubin levels. However, no easy and accessible tool for self-assessing neonatal jaundice is currently available. Smartphones could potentially be transformed into a medical device that could be used by both patients and practitioners. OBJECTIVE: To investigate whether a digital image produced by a camera embedded on a smartphone can be a used as a screening tool for neonatal hyperbilirubinemia. STUDY DESIGN: A total of 64 randomly selected newborns were enrolled. The inclusion criteria were healthy Caucasians, gestational age >35 weeks, age >24 hours and ≤14 days old, and parental informed consent. The exclusion criteria were facial skin lesions and light treatment. Images of the glabella were obtained with an iPhone 6 via i) directly applied pressure, ii) a dermatoscope, or iii) a dermatoscope equipped with a Wratten No. 11 filter. The red, green and blue colour intensities of each image were compared to bilirubin levels. RESULTS: Only the dermatoscope-acquired intensities of the green and blue channels were significantly correlated (p < 0.001) with bilirubin measurements (Pearson's r: 0.59 and 0.48, respectively). For the green and blue channels, discrimination limits of 212 and 190, respectively, revealed a sensitivity and specificity of 100% and 62.5%, respectively, for green and 90.9% and 60%, respectively, for blue for a plasma bilirubin above 205 µmol/L. CONCLUSIONS: The results of this study indicate that a smartphone equipped with a consistent light source in the form of a dermatoscope may be a simple screening tool for neonatal hyperbilirubinemia. However, the method requires some improvement before clinical application.

Exposure to phenols, parabens and UV filters: Associations with loss-of-function mutations in the filaggrin gene in men from the general population.

BACKGROUND: Filaggrin is an epidermal protein that is important for normal skin barrier functions. Up to 10% of Europeans and Asians carry filaggrin gene (FLG) loss-of function mutations that appear to facilitate trans-epidermal penetration of certain chemicals. We previously showed that mutation carriers have higher internal exposure to certain phthalates, compared to controls, and hypothesized that they could have increased trans-epidermal penetration of other chemicals. OBJECTIVES: We investigated exposure to non-persistent chemicals in young Danish men with and without FLG mutations. METHODS: Concentrations of eight simple phenols, six parabens and nine UV filters were analysed in urine from 65 FLG loss-of-function mutation carriers and 130 non-carriers (controls). Regression analyses, controlling for urinary dilution and confounders, were performed to estimate associations between FLG mutation status and chemical concentrations in urine. RESULTS: FLG mutation carriers had 80% (13-180%) higher urinary concentrations of methyl paraben (MeP) and 91% (13-219%) higher concentrations of n-propyl paraben (n-PrP) than controls. For 13 compounds, levels were higher in FLG mutation carriers, although differences were only statistically significant for MeP and n-PrP. Combined statistical analysis of concentrations of all the 18 compounds that were detectable in >10% of subjects, suggested that concentrations were generally higher in mutation carriers (p=0.03). CONCLUSION: FLG loss-of-function mutation carriers have a higher internal exposure to some non-persistent chemicals, independently of atopic dermatitis. This may be due to increased trans-epidermal absorption and/or higher exposure, and mutation carriers may constitute a group susceptible to increased absorption of chemicals and topical medication.

Hand eczema, atopic dermatitis and filaggrin mutations in adult Danes: a registry-based study assessing risk of disability pension.

BACKGROUND: Atopic dermatitis and hand eczema often impair the ability of people to work. Only a few studies have investigated whether individuals with loss-of-function filaggrin gene (FLG) mutations, who often have severe and early onset of dermatitis, experience occupational consequences. OBJECTIVE: To investigate the personal consequences of having atopic dermatitis and/or hand eczema and FLG mutations. METHOD: Adult Danes from the general population (n = 3247) and patients with atopic dermatitis and/or hand eczema (n = 496) were genotyped for common FLG mutations, and completed a questionnaire about skin symptoms and hand eczema. Socioeconomic variables, including disability pension, and information on work in risk occupations were retrieved from national registries. The reasons for granting disability pension were unknown. RESULTS: Disability pension was associated with hand eczema in the general population, especially among individuals with a history of atopic dermatitis. Moreover, self-reported hand eczema and atopic dermatitis were associated with particularly high risk of disability pension among FLG mutation carriers [odds ratio (OR) 4.02 and 95% confidence interval (CI): 1.15-14.11; and OR 6.01 and 95%CI: 2.37-15.34, respectively]. Furthermore, 60% of the FLG mutation carriers with atopic dermatitis who developed hand eczema had experienced symptoms before adulthood. CONCLUSION: In the general population, self-reported hand eczema and atopic dermatitis, particularly in individuals with a genetically impaired skin barrier, were associated with disability pension, suggesting that FLG mutations carriers with a history of atopic dermatitis and hand eczema could benefit from early attention with respect to choice of occupation.

Weekday variation in triglyceride concentrations in 1.8 million blood samples.

Triglyceride (TG) concentration is used as a marker of cardiometabolic risk. However, diurnal and possibly weekday variation exists in TG concentrations. The objective of this work was to investigate weekday variation in TG concentrations among 1.8 million blood samples drawn between 2008 and 2015 from patients in the Capital region of Denmark. Plasma TG was extracted from a central clinical laboratory information system. Weekday variation was investigated by means of linear mixed models. In addition to the profound diurnal variation, the TG concentration was 4.5% lower on Fridays compared with Mondays (P < 0.0001). The variation persisted after multiple adjustments for confounders and was consistent across all sensitivity analyses. Out-patients and in-patients, respectively, had 5.0% and 1.9% lower TG concentrations on Fridays compared with Mondays (both P < 0.0001). The highest weekday variations in TG concentrations were recorded for out-patients between the ages of 9 and 26 years, with up to 20% higher values on Mondays compared with Fridays (all P < 0.05). In conclusion, TG concentrations were highest after the weekend and gradually declined during the week. We suggest that unhealthy food intake and reduced physical activity during the weekend increase TG concentrations which track into the week. This weekday variation may carry implications for public health and future research practice.

Health-related quality of life in adult dermatitis patients stratified by filaggrin genotype.

BACKGROUND: Information concerning health-related quality of life (HRQoL) and comorbidities of adult dermatitis patients stratified by loss-of-function mutations in the filaggrin gene (FLG) is limited. OBJECTIVE: To investigate HRQoL, skin symptoms and comorbidities in adult FLG mutation carriers. METHODS: This cross-sectional study included patients diagnosed with atopic dermatitis and/or hand eczema (n = 520). Patients completed questionnaires about dermatitis, skin symptoms, HRQoL, and comorbidities, including actinic keratosis, and atopic and mental disorders. RESULTS: FLG mutations (R501X, 2282del4, and R2447X) were identified in 16.9% of patients, and were significantly associated not only with atopic dermatitis, but also independently with skin fissures on the fingers and heels, and self-reported actinic keratosis. Although FLG mutations were significantly associated with reduced HRQoL, as measured by use of the Dermatology Life Quality Index (DLQI), no association with self-reported anxiety or depression was identified. Notably, the highest median DLQI score, reflecting greater impairment, was reported by patients with both FLG mutations and atopic dermatitis. Overall, 19.7% of patients with both atopic dermatitis and FLG mutations reported a 'large or extremely large' impact on their lives; this represents twice the prevalence seen in patients with atopic dermatitis and wild-type FLG (9.6%). CONCLUSION: Patients with both atopic dermatitis and common FLG mutations are more frequently affected by reduced HRQoL.

Large D-Dimer Fluctuation in Normal Pregnancy: A Longitudinal Cohort Study of 4,117 Samples from 714 Healthy Danish Women.

Introduction. D-dimer levels increase throughout pregnancy, hampering the usefulness of the conventional threshold for dismissing thromboembolism. This study investigates the biological fluctuation of D-dimer in normal pregnancy. Methods. A total of 801 healthy women with expected normal pregnancies were recruited. D-dimer was repeatedly measured during pregnancy, at active labor, and on the first and second postpartum days. Percentiles for each gestational week were calculated. Each individual D-dimer was normalized by transformation into percentiles for the relevant gestational age or delivery group. The range in percentage points during the pregnancy and the delivery was calculated, and reference intervals were calculated for each pregnancy trimester, during vaginal delivery and scheduled and emergency cesarean section, and for the first and second day postpartum. Results. D-dimer increased during pregnancy; the maximal fluctuation was approximately 20 percentile points in approximately half of the women. In one out of ten women, the D-dimer values fluctuated by more than 50 percentile points. Conclusions. Due to the biological variation in D-dimer within each individual woman during normal pregnancy, repeated D-dimer measurements are of no clinical use in the evaluation of thromboembolic events during pregnancy.

Hepcidin levels are low during pregnancy and increase around delivery in women without iron deficiency - a prospective cohort study.

OBJECTIVE: To investigate hepcidin during pregnancy, delivery and postpartum in women with sufficient iron supplementation. METHODS: Hepcidin was measured using LC-MS spectroscopy in 37 women during pregnancy, delivery and postpartum period in this longitudinal study. RESULTS: Hepcidin was low during pregnancy and increased at delivery and postpartum. No correlations with inflammatory markers or iron metabolism were observed during pregnancy; at delivery a correlation with inflammatory markers was observed. CONCLUSION: During pregnancy, in women with sufficient iron supplementation, hepcidin is low and does not reflect iron status. During delivery and the postpartum period, hepcidin functions as a marker of inflammation.

Postprandial prolactin suppression appears absent in antipsychotic-treated male patients.

INTRODUCTION: Hyperprolactinemia is a common side-effect of antipsychotic treatment. Antipsychotics and hyperprolactinemia are both considered risk factors of metabolic disturbances and diabetes. Investigations on prolactin response to meal ingestion in antipsychotic-treated patients are missing. MATERIAL AND METHODS: In a case-control design, 49 antipsychotic-treated, clinically stable, non-diabetic, schizophrenia spectrum male patients were compared with 93 healthy male controls by age (33.1, SD 7.4 vs. 32.9, SD 6.6 years), body mass index (26.2, SD 4.6 vs. 26.1, SD 3.9 kg/m(2)) and waist circumference (96.4, SD 13.0 vs. 96.7, SD 11.9 cm). Serum-prolactin was measured in the morning and 90 min after ingestion of a standardized liquid meal (2268 kJ). RESULTS: Fasting prolactin levels varied considerably, and mean fasting prolactin levels did not significantly differ between patients and controls (12.33, SD 11.58 vs. 10.06, SD 8.67 ng/ml, p = 0.623). In the controls, postprandial serum prolactin was significantly reduced (Δ -2.53, SD 9.75 ng/ml, p = 0.016). In antipsychotic-treated patients postprandial serum prolactin tended to increase (Δ 2.62, SD 10.96 ng/ml, p = 0.081). Analyses of subgroups based on the prolactinogenic liability of their antipsychotic treatment indicated 22 to 65% higher postprandial prolactin levels with high and intermediate prolactinogenic antipsychotics. DISCUSSION: A physiological postprandial suppression of serum prolactin appears absent in antipsychotic-treated males. Marked variability in fasting prolactin levels may reflect individual variations in the diurnal cycle. Uniform acquisition procedures accounting for diurnal variation and food intake may enhance reliability of prolactin levels in antipsychotic-treated male patients.

n-3 PUFA esterified to glycerol or as ethyl esters reduce non-fasting plasma triacylglycerol in subjects with hypertriglyceridemia: a randomized trial.

To date, treatment of hypertriglyceridemia with long-chain n-3 polyunsaturated fatty acids (n-3 PUFA) has been investigated solely in fasting and postprandial subjects. However, non-fasting triacylglycerols are more strongly associated with risk of cardiovascular disease. The objective of this study was to investigate the effect of long-chain n-3 PUFA on non-fasting triacylglycerol levels and to compare the effects of n-3 PUFA formulated as acylglycerol (AG-PUFA) or ethyl esters (EE-PUFA). The study was a double-blinded randomized placebo-controlled interventional trial, and included 120 subjects with non-fasting plasma triacylglycerol levels of 1.7-5.65 mmol/L (150-500 mg/dL). The participants received approximately 3 g/day of AG-PUFA, EE-PUFA, or placebo for a period of eight weeks. The levels of non-fasting plasma triacylglycerols decreased 28% in the AG-PUFA group and 22% in the EE-PUFA group (P < 0.001 vs. placebo), with no significant difference between the two groups. The triacylglycerol lowering effect was evident after four weeks, and was inversely correlated with the omega-3 index (EPA + DHA content in erythrocyte membranes). The omega-3 index increased 63.2% in the AG-PUFA group and 58.5% in the EE-PUFA group (P < 0.001). Overall, the heart rate in the AG-PUFA group decreased by three beats per minute (P = 0.045). High-density lipoprotein (HDL) cholesterol increased in the AG-PUFA group (P < 0.001). Neither total nor non-HDL cholesterol changed in any group. Lipoprotein-associated phospholipase A2 (LpPLA2) decreased in the EE-PUFA group (P = 0.001). No serious adverse events were observed. Supplementation with long-chain n-3 PUFA lowered non-fasting triacylglycerol levels, suggestive of a reduction in cardiovascular risk. Regardless of the different effects on heart rate, HDL, and LpPLA2 that were observed, compared to placebo, AG-PUFA, and EE-PUFA are equally effective in reducing non-fasting triacylglycerol levels.

Glucometabolic hormones and cardiovascular risk markers in antipsychotic-treated patients.

OBJECTIVE: Treatment with antipsychotic drugs is widely associated with metabolic side effects such as weight gain and disturbed glucose metabolism, but the pathophysiologic mechanisms are unclear. METHOD: Fifty nondiabetic (fasting plasma glucose ≤ 7.0 mmol/L), antipsychotic-treated male patients (ICD-10 diagnosis code F20, F21, F22, F25, F28, or F60; mean ± SD age = 33.0 ± 6.7 years; body mass index [BMI; kg/m²] = 26.0 ± 4.7; waist circumference = 95.9 ± 13.3 cm; glycated hemoglobin A1c [HbA1c] = 5.7% ± 0.3%) and 93 age- and waist circumference-matched healthy male controls (age = 33 ± 7.3 years; BMI = 26.1 ± 3.9; waist circumference = 94.6 ± 11.9 cm; HbA1c = 5.7% ± 0.3%) participated in this cross-sectional study. Blood was sampled in the fasting state and 90 minutes after ingestion of a standardized liquid meal (2,268 kJ). The primary outcomes were glucometabolic hormones and cardiovascular risk markers. Data were collected between March 2008 and February 2010. RESULTS: Compared to healthy controls, patients were characterized by elevated fasting levels of proinsulin, C-peptide, and glucose-dependent insulinotropic polypeptide (GIP) (P < .05) and higher postprandial levels of insulin, proinsulin, C-peptide, and GIP (P ≤ .02). Also, patients exhibited elevated plasma levels of C-reactive protein and signs of dyslipidemia. Fasting plasma levels of insulin, glucagon, glucagon-like peptide-1 (GLP-1), ghrelin, leptin, adiponectin, tumor necrosis factor-α, plasminogen activator inhibitor-1, and interleukin-6 and postprandial levels of glucagon, GLP-1, ghrelin, leptin, and adiponectin did not differ between groups. CONCLUSIONS: Presenting with an insulin resistant-like pattern, including beta cell hypersecretion and elevated GIP levels, nondiabetic antipsychotic-treated patients display emerging signs of dysmetabolism and a compromised cardiovascular risk profile. The appetite-regulating hormones GLP-1 and ghrelin appear not to be influenced by antipsychotic treatment. Our findings provide new clinical insight into the pathophysiology associated with metabolic side effects of antipsychotic treatment and put emphasis on the importance of implementing metabolic screening into psychiatric practice. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT00627757.

Cancer antigen 125 after delivery in women with a normal pregnancy: a prospective cohort study.

OBJECTIVE: To establish reference intervals for cancer antigen 125 (CA-125) in women with expected normal pregnancy, delivery, and early postpartum period. DESIGN: Prospective observational study. SETTING: Department of Clinical Biochemistry and Obstetrics, Copenhagen University Hospital, Gentofte, Denmark. POPULATION: Eight hundred and one women with expected normal pregnancies were investigated. Of these, 640 delivered vaginally, 82 by emergency cesarean section, and 79 by elective cesarean section; 720 women had uncomplicated pregnancies. METHODS: Samples were collected at gestational weeks 13-20, 21-28, 29-34, 35-42, during labor, and on first and second day postpartum. Reference intervals were calculated for each gestational period as recommended by the International Federation of Clinical Chemistry and Laboratory Medicine. MAIN OUTCOME MEASURES: Concentration of serum CA-125 during the gestational period and around delivery. RESULTS: CA-125 was fairly stable below 35 U/mL during pregnancy but increased markedly during vaginal delivery, to a minor degree during emergency cesarean section, and only slightly during elective cesarean section. In the early postpartum period, CA-125 decreased with an apparent half-life of 24 h. CONCLUSIONS: The CA-125 cut-off value (<35 U/mL) used for non-pregnant women can be used for women during pregnancy after gestational week 13 as a supplement to ultrasound evaluation of ovarian cysts. The wide range of CA-125 concentration during normal pregnancies makes it unlikely that small fluctuations in CA-125 can be clinically useful for identifying other conditions. Measuring CA-125 around the time of delivery is not recommended. Gestational age-specific reference intervals during normal pregnancy are not needed.

Associations of filaggrin gene loss-of-function variants and human papillomavirus-related cancer and pre-cancer in Danish adults.

PURPOSE: Filaggrin proteins are expressed in the skin, oral cavity, oesophagus, and cervical mucose. Loss-of-function mutations in the filaggrin gene (FLG) reduce filaggrin expression and cause an impaired skin barrier function. We hypothesized that FLG mutation carriers would be more susceptible to human papillomavirus (HPV) infection and thus a higher risk of HPV-related cancer and pre-cancer. We investigated the association of the FLG genotype with incidence of HPV-related cancer of cervix, vagina, vulva, penis, anus and head and neck, and pre-cancer of the cervix. METHODS: We included 13,376 persons from four population-based studies conducted in the same background population in Copenhagen, Denmark. Participants were genotyped for the most common FLG mutations in Europeans. Information on cancer was obtained from The Danish Cancer Registry until 11 July 2011. RESULTS: There were 489 cases of prevalent and 97 cases of incident HPV-related cancer and pre-cancer (median follow-up 11.5 years). There was a statistically significant association between FLG genotype and incident HPV-related cancer and pre-cancer with a hazard ratio, HR = 2.1 (95% confidence intervals, CI: 1.2, 3.7) for FLG mutation carriers vs. wild types. CONCLUSIONS: FLG loss-of-function mutations were associated with higher incidence of HPV-related cancers and pre-cancers that are potentially screening and vaccine preventable.

No association between loss-of-function mutations in filaggrin and diabetes, cardiovascular disease, and all-cause mortality.

BACKGROUND: Common loss-of-function mutations in the filaggrin gene (FLG) are a major predisposing risk factor for atopic disease due to reduced epidermal filaggrin protein levels. We previously observed an association between these mutations and type 2 diabetes and hypothesized that an inherited impairment of skin barrier functions could facilitate low-grade inflammation and hence increase the risk of diabetes and cardiovascular disease. We examined the association between loss-of-function mutations in FLG and diabetes, stroke, ischemic heart disease (IHD), and all-cause mortality in the general population. METHODS: The R501X and 2282del4 loss-of function mutations in FLG were genotyped in four Danish study populations including a total of 13373 adults aged 15-77 years. Two of the studies also genotyped the R2447X mutation. By linkage to Danish national central registers we obtained information for all participants on dates of diagnoses of diabetes, stroke, and IHD, as well as all-cause mortality. Data were analyzed by Cox proportional hazard models and combined by fixed effect meta-analyses. RESULTS: In meta-analyses combining the results from the four individual studies, carriage of loss-of-function mutations in FLG was not associated with incident diabetes (hazard ratio (HR) (95% confidence intervals (CI)) = 0.95 (0.73, 1.23), stroke (HR (95% CI) = 1.27 (0.97, 1.65), ischemic heart disease (HR (95%CI) = 0.92 (0.71, 1.19), and all-cause mortality (HR (95%CI) = 1.02 (0.83, 1.25)). Similar results were obtained when including prevalent cases in logistic regression models. CONCLUSION: Our results suggest that loss-of-function mutations in FLG are not associated with type 2 diabetes, cardiovascular disease, and all-cause mortality. However, larger studies with longer follow-up are needed to exclude any associations.

Filaggrin compound heterozygous patients carry mutations in trans position.

More than 40 null mutations in the filaggrin (FLG) gene are described. It is therefore possible to find two different null mutations in one individual (compound heterozygosity). It has been generally perceived that homozygous and compound heterozygous individuals were genotypically comparable; however, this has not been scientifically investigated. Two different FLG null mutations in the same individual may be in trans position, meaning that each mutation locates to a different allele functionally equivalent to homozygosity, or may be in cis position, meaning that both mutations locate to the same allele functionally equivalent to heterozygosity. To experimentally investigate allelic in cis versus in trans configuration of the two most common filaggrin (FLG) mutations (R501X and 2282del4) in compound heterozygous individuals. Testing for in cis or in trans allele configuration was performed by means of allele-specific PCR amplification and analysis of PCR products by agarose gel electrophoresis. All R501X/2282del4 compound heterozygous samples collected over a 4-year period of routine FLG mutation testing were investigated. In total, 37 samples were tested. All thirty-seven R501X/2282del4 compound heterozygous individuals were found to carry the two mutations in trans position. FLG null mutation compound heterozygous individuals can be considered functionally equivalent to FLG null mutation homozygosity for any of the two mutations.

Comparison of immunoglobulin E measurements on IMMULITE and ImmunoCAP in samples consisting of allergen-specific mouse-human chimeric monoclonal antibodies towards allergen extracts and four recombinant allergens.

BACKGROUND: Specific immunoglobulin E (IgE) antibody in vitro tests are performed on enzyme immunoassay systems. Poor agreement among systems has been reported and comparisons have been made exclusively with allergen extracts - not with recombinant allergens. Here we compare the ImmunoCAP and the IMMULITE systems. METHODS: Ten patient samples with positive IgE toward egg white, birch pollen or cat or dog dander were compared using allergen extracts or the recombinant allergens Gal d 1, Bet v 1, Fel d 1 and Can f 1 with the two assay systems. Comparisons were also performed using four monoclonal mouse-human chimeric IgE antibodies specific for the same allergenic components. RESULTS: IMMULITE estimated a higher allergen-specific IgE concentration in sera than ImmunoCAP when testing with allergen extracts as well as recombinant allergens. The chimeric antibodies gave an equivalent response in the total IgE and specific IgE (sIgE) with an average ratio of 1.08 (range 0.9-1.3) on ImmunoCAP. In contrast, IMMULITE exhibited sIgE signals that were substantially higher than the summed level of IgE for all four chimeric antibodies (average ratio 2.96 and range 1.7-4.3). CONCLUSION: Comparison using chimeric antibodies allowed the evaluation of the true performance of the systems. ImmunoCAP measured total IgE and sIgE equally, whereas IMMULITE displayed higher sIgE signals when compared to the summed level of total IgE for all four chimeric antibodies. Results obtained with the two assay systems are not interchangeable by means of mathematical conversion.

Carriers of filaggrin gene (FLG) mutations avoid professional exposure to irritants in adulthood.

BACKGROUND: Loss-of-function mutations in the filaggrin gene (FLG) are associated with xerosis, atopic dermatitis, and early onset of hand eczema. Irritant exposure is a risk factor for occupational hand eczema, and FLG mutations increase the risk of occupational irritant contact dermatitis on the hands in hospital cohorts. It is unknown whether FLG mutations affect the level of irritant exposure. OBJECTIVES: To evaluate whether exposure to occupational irritants was dependent on FLG mutations, atopic dermatitis, and age at hand eczema onset. METHODS: Randomly chosen Danish adults completed a questionnaire on general health and occupational exposures. Genotyping for FLG mutations (R501X, 2282del4, and R2447X) and patch testing were performed. RESULTS: Overall, 38.7% of subjects reported present or previous occupational exposure to irritants. Among individuals who reported hand eczema onset before entering their work life, 50.6% (45/89) of FLG non-mutation carriers became exposed to irritants, as compared with 28.6% (4/14) of heterozygous and 0% (0/6) of homozygous mutation carriers (p = 0.006). Avoidance was conspicuous among mutation carriers reporting childhood hand eczema and atopic dermatitis (odds ratio 0.08, 95% confidence interval 0.01-0.65). CONCLUSIONS: Carriers of FLG mutations who have had hand eczema onset in childhood avoid occupational exposure to irritants; the association is most marked with homozygous mutation status combined with atopic dermatitis.