Influence of non-pharmaceutical interventions during the COVID-19 pandemic on respiratory viral infections - a prospective population-based cohort study.

Non-pharmaceutical interventions (NPI) have been proven successful in a population-based approach to protect from SARS-CoV-2 transmission during the COVID-19 pandemic. As a consequential-effect, a reduction in the spread of all respiratory viruses has been observed, but the primary factors behind this phenomenon have yet to be identified. We conducted a subgroup analysis of participants from the ELISA study, a prospective longitudinal cohort study on SARS-CoV-2 transmission, at four timepoints from November 2020 - September 2022. The aim was to provide a detailed overview of the circulation of respiratory viruses over 2 years and to identify potential personal risk factors of virus distribution. All participants were screened using qPCR for respiratory viral infections from nasopharyngeal swabs and answered a questionnaire regarding behavioral factors. Several categories of risk factors for the transmission of respiratory viruses were evaluated using a scoring system. In total, 1,124 participants were included in the study, showing high adherence to governmental-introduced NPI. The overall number of respiratory virus infections was low (0-4.9% of participants), with adenovirus (1.7%), rhino-/enterovirus (3.2%) and SARS-CoV-2 (1.2%) being the most abundant. We detected an inverse correlation between the number and intensity of NPI and the number of detected respiratory viruses. More precisely, the attendance of social events and household size was associated with rhino-/enterovirus infection while social contacts were associated with being positive for any virus. NPI introduced during the COVID-19 pandemic reduced the occurrence of seasonal respiratory viruses in our study, showing different risk-factors for enhanced transmission between viruses. Trial registration: DRKS.de, German Clinical Trials Register (DRKS), Identifier: DRKS00023418, Registered on 28 October 2020.

Targeted DNA Methylation Analysis Facilitates Leukocyte Counts in Dried Blood Samples.

BACKGROUND: Cell-type specific DNA methylation (DNAm) can be employed to determine the numbers of leukocyte subsets in blood. In contrast to conventional methods for leukocyte counts, which are based on cellular morphology or surface marker protein expression, the cellular deconvolution based on DNAm levels is applicable for frozen or dried blood. Here, we further enhanced targeted DNAm assays for leukocyte counts in clinical application. METHODS: DNAm profiles of 40 different studies were compiled to identify CG dinucleotides (CpGs) with cell-type specific DNAm using a computational framework, CimpleG. DNAm levels at these CpGs were then measured with digital droplet PCR in venous blood from 160 healthy donors and 150 patients with various hematological disorders. Deconvolution was further validated with venous blood (n = 75) and capillary blood (n = 31) that was dried on Whatman paper or on Mitra microsampling devices. RESULTS: In venous blood, automated cell counting or flow cytometry correlated well with epigenetic estimates of relative leukocyte counts for granulocytes (r = 0.95), lymphocytes (r = 0.97), monocytes (r = 0.82), CD4 T cells (r = 0.84), CD8 T cells (r = 0.94), B cells (r = 0.96), and NK cells (r = 0.72). Similar correlations and precisions were achieved for dried blood samples. Spike-in with a reference plasmid enabled accurate epigenetic estimation of absolute leukocyte counts from dried blood samples, correlating with conventional venous (r = 0.86) and capillary (r = 0.80) blood measurements. CONCLUSIONS: The advanced selection of cell-type specific CpGs and utilization of digital droplet PCR analysis provided accurate epigenetic blood counts. Analysis of dried blood facilitates self-sampling with a finger prick, thereby enabling easier accessibility to testing.

Investigations into Simplified Analogues of the Herbicidal Natural Product (+)-Cornexistin.

We report the design, synthesis and biological evaluation of simplified analogues of the herbicidal natural product (+)-cornexistin. Guided by an X-Ray co-crystal structure of cornexistin bound to transketolase from Zea mays, we attempted to identify the key interactions that are necessary for cornexistin to maintain its herbicidal profile. This resulted in the preparation of three novel analogues investigating the importance of substituents that are located on the nine-membered ring of cornexistin. One analogue maintained a good level of biological activity and could provide researchers insights in how to further optimize the structure of cornexistin for commercialization in the future.

[Intersectoral management of patients with abnormal liver enzymes and non-alcoholic fatty liver disease (NAFLD)]. / Intersektorales Management von Patienten mit unklarer Leberwerterhöhung und nichtalkoholischer Fettlebererkrankung (NAFLD).

The prevalence of fatty liver disease has increased significantly in Germany in recent years. With an estimated 18 million German citizens being affected, it is now among the most prevalent diseases. Furthermore, it is also considered a relevant and independent risk factor for other common cardiovascular diseases such as heart attack or stroke. Finally, diabetes mellitus promotes the development of and an unfavorable course of fatty liver disease. Given the high prevalence and complications, the German healthcare system is reaching its limits.Therefore, close coordination of all healthcare providers and specialists involved in the treatment of these patients is essential. In an expert consensus involving private practice and hospital doctors from the fields of gastroenterology, endocrinology, cardiology, general practitioners and laboratory physicians, as well as in close coordination with patient representatives, we have designed a concept for the care of these patients in the German healthcare system. Necessary developments are also addressed. In addition to being useful as a practical guideline, this should also support health policy work, especially in the development of practical care solutions at the medical level.

Confirmation of guideline-defined hepatitis C screening strategies within the 'Check-Up35+' examination in the primary care setting.

BACKGROUND AND AIMS: Screening strategies for undiagnosed infections are fundamental for hepatitis C virus (HCV) elimination. We previously investigated HCV prevalence and screening strategies in an urban primary care setting. IV drug abuse, blood transfusion before 1992, immigration, or elevated ALT were identified as risk factors in a post hoc analysis and diagnosed 83% of unknown HCV-RNA-positive cases by screening only 26% of the population. We aimed to validate prospectively the proposed screening algorithm in two independent urban and rural cohorts and to analyse for potential differences. METHODS: Anti-HCV and ALT were included in a routine check-up together with a questionnaire covering risk factors. HCV-RNA was analysed in anti-HCV-positive individuals. RESULTS: In urban and rural areas, 4323 and 9321 individuals were recruited. The anti-HCV prevalence was 0.56% and 0.49%, and 0.1% of patients were HCV-RNA-positive in both regions. Fifty-two anti-HCV positive patients including eight HCV-RNA-positive cases were unaware of the infection (number needed to screen to detect one unknown anti-HCV-positive individual: 262). At least one of the three aforementioned risk factors or elevated serum ALT was present in 3000 patients (22%). Restricting HCV screening to only those with risk factors, 52% and 75% of all anti-HCV and HCV-RNA-positive undiagnosed patients were identified (number needed to screen: 111). CONCLUSIONS: We confirm prospectively the efficiency of a risk-based HCV screening. The risk-based algorithm should be evaluated in other countries with similarly low HCV prevalence as in Germany to achieve WHO HCV elimination goals.

High Throughput FISH Screening Identifies Small Molecules That Modulate Oncogenic lncRNA MALAT1 via GSK3B and hnRNPs.

Traditionally, small molecule-based drug discovery has mainly focused on proteins as the drug target. Opening RNA as an additional target space for small molecules offers the possibility to therapeutically modulate disease-driving non-coding RNA targets as well as mRNA of otherwise undruggable protein targets. MALAT1 is a highly conserved long-noncoding RNA whose overexpression correlates with poor overall patient survival in some cancers. We report here a fluorescence in-situ hybridization-based high-content imaging screen to identify small molecules that modulate the oncogenic lncRNA MALAT1 in a cellular setting. From a library of FDA approved drugs and known bioactive molecules, we identified two compounds, including Niclosamide, an FDA-approved drug, that lead to a rapid decrease of MALAT1 nuclear levels with good potency. Mode-of-action studies suggest a novel cellular regulatory pathway that impacts MALAT1 lncRNA nuclear levels by GSK3B activation and the involvement of the RNA modulating family of heterogenous nuclear ribonucleoproteins (hnRNPs). This study is the basis for the identification of novel targets that lead to a reduction of the oncogenic lncRNA MALAT1 in a cancer setting.

REACT DX registry: Real world REACTion to atrial high rate episodes detected in implantable cardioverter-defibrillator recipients with a DX lead.

BACKGROUND: Atrial fibrillation (AF) is associated with significant morbidity and is predicted by atrial high rate events. The early detection of AF is paramount to timely interventions to reduce the morbidity of AF. The DX ICD system combined with Home Monitoring® allows for continuous atrial rhythm monitoring without the need for a dedicated atrial lead. OBJECTIVE: To establish the reaction to and timing of reactions to the detection of atrial high rate episodes (AHRE). METHODS: A prospective cohort of DX ICD systems was followed up and the response to AHREs was collected and evaluated. RESULTS: A total of 234 patients were enrolled; an AHRE ⩾ 6 min was detected in 13.7% of patients (n= 32) within a mean follow-up duration of 16 months. A high rate of oral anticoagulation (OAC) prescription was seen with the detection of AHREs in patients with a not-low risk CHA2DS2-VASc score. There was a delay in this prescription highlighting the potential to improve the timeliness of patient care in this group of patients. CONCLUSIONS: The DX ICD system provides rapid and ongoing atrial rhythm monitoring such that physicians are rapidly aware of AHRE without the need for a dedicated atrial lead, but local protocols are needed to improve the response time of anti-coagulation prescription.

Compilation and evaluation of a fatty acid mimetics screening library.

Focused compound libraries are well-established tools for hit identification in drug discovery and chemical probe development. We present the compilation and application of a focused screening library of fatty acid mimetics (FAMs), which are compounds designed to bind the orthosteric site of proteins that endogenously accommodate natural fatty acids and lipid metabolites. This set complies with chemical properties of FAM and was found suitable for use also in cellular setting. Several hits were retrieved in screening the focused library against diverse fatty acid binding targets including the enzymes soluble epoxide hydrolase (sEH) and leukotriene A4 hydrolase (LTA4H), the nuclear receptors peroxisome proliferator-activated receptor γ (PPARγ) and retinoid X receptor α (RXRα), the carrier proteins fatty acid binding protein 4 and 5 (FABP4 and FABP5), as well as the G-protein coupled receptors leukotriene B4 receptor 1 (BLT1) and free-fatty acid receptor 1 (FFAR1). Thus, the focused FAM library is suitable to obtain chemical starting matter for fatty acid binding proteins and provides a valuable extension to available screening collections.

One-year surveillance of SARS-CoV-2 transmission of the ELISA cohort: A model for population-based monitoring of infection risk.

With newly rising coronavirus disease 2019 (COVID-19) cases, important data gaps remain on (i) long-term dynamics of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection rates in fixed cohorts (ii) identification of risk factors, and (iii) establishment of effective surveillance strategies. By polymerase chain reaction and antibody testing of 1% of the local population and >90,000 app-based datasets, the present study surveilled a catchment area of 300,000 inhabitants from March 2020 to February 2021. Cohort (56% female; mean age, 45.6 years) retention was 75 to 98%. Increased risk for seropositivity was detected in several high-exposure groups, especially nurses. Unreported infections dropped from 92 to 29% during the study. "Contact to COVID-19-affected" was the strongest risk factor, whereas public transportation, having children in school, or tourism did not affect infection rates. With the first SARS-CoV-2 cohort study, we provide a transferable model for effective surveillance, enabling monitoring of reinfection rates and increased preparedness for future pandemics.

N-Aryl Mercaptopropionamides as Broad-Spectrum Inhibitors of Metallo-ß-Lactamases.

Drug-resistant pathogens pose a global challenge to public health as they cause diseases that are extremely difficult to cure. Metallo-ß-lactamases (MBLs) are a diverse set of zinc-containing enzymes that catalyze the hydrolysis of ß-lactam drugs, including carbapenems, which are considered as the last resort to fight severe infections. To restore the activity of current ß-lactam antibiotics and to offer an orthogonal strategy to the discovery of new antibiotics, we have identified a series of polar N-aryl mercaptopropionamide derivatives as potent inhibitors of several class B1 MBLs. We have identified a hit structure with high selectivity restoring the effect of imipenem and reducing minimum inhibitory concentration (MIC) values up to 256-fold in resistant isolates from Escherichia coli. Furthermore, the combination of imipenem with our inhibitor showed in vivo efficacy in a Galleria mellonella model, increasing the survival rate of infected larvae by up to 31%.

Toward Clinical Application of Leukocyte Counts Based on Targeted DNA Methylation Analysis.

BACKGROUND: Differential leukocyte counts are usually measured based on cellular morphology or surface marker expression. It has recently been shown that leukocyte counts can also be determined by cell-type-specific DNA methylation (DNAm). Such epigenetic leukocyte counting is applicable to small blood volumes and even frozen material, but for clinical translation, the method needs to be further refined and validated. METHODS: We further optimized and validated targeted DNAm assays for leukocyte deconvolution using 332 venous and 122 capillary blood samples from healthy donors. In addition, we tested 36 samples from ring trials and venous blood from 266 patients diagnosed with different hematological diseases. Deconvolution of cell types was determined with various models using DNAm values obtained by pyrosequencing or digital droplet PCR (ddPCR). RESULTS: Relative leukocyte quantification correlated with conventional blood counts for granulocytes, lymphocytes, B cells, T cells (CD4 or CD8), natural killer cells, and monocytes with pyrosequencing (r = 0.84; r = 0.82; r = 0.58; r = 0.50; r = 0.70; r = 0.61; and r = 0.59, respectively) and ddPCR measurements (r = 0.65; r = 0.79; r = 0.56; r = 0.57; r = 0.75; r = 0.49; and r = 0.46, respectively). In some patients, particularly with hematopoietic malignancies, we observed outliers in epigenetic leukocyte counts, which could be discerned if relative proportions of leukocyte subsets did not sum up to 100%. Furthermore, absolute quantification was obtained by spiking blood samples with a reference plasmid of known copy number. CONCLUSIONS: Targeted DNAm analysis by pyrosequencing or ddPCR is a valid alternative to quantify leukocyte subsets, but some assays require further optimization.

Age Dependence of Liver Enzymes: An Analysis of Over 1,300,000 Consecutive Blood Samples.

BACKGROUND & AIMS: Upper levels of normal for alanine aminotransferase (ALT), aspartate aminotransferase (AST), and γ-glutamyltransferase (GGT) generally take sex into account, but not age. This simplification may lead to misclassification and burden the patient and health system unnecessarily. METHODS: Consecutive blood samples were analyzed from a German laboratory. Subcohorts included samples from a prescribed routine check-up and a healthy cohort, defined as patients without increased GGT, triglyceride, cholesterol, glycated hemoglobin, or glucose levels, and without known hepatitis B. RESULTS: A total of 1,369,180 blood samples were analyzed from 601,779 participants (50.8% female; mean age, 58.5 y; SD, 18.0 y). There is an extreme age dependence in ALT values for men: increased values were seen in 20.0% (95% CI, 19.5%-20.4%) of patients in the age group of 25 to 34 years, but only 6.7% (95% CI, 6.4%-7.0%) for the ages of 65 to 74 years. The 95th percentile reaches values greater than 80 U/L instead of 50 U/L at the age of 35, and decrease to less than 50 U/L by the age of 75. Similar qualitative results were found in the healthy and prescribed routine check-up subcohorts. The age dependence is much weaker for ALT in women. The proportion of women with an increased AST level increases from approximately 6% to 12% at approximately age 50. The 95th percentile for GGT increases up to the age of 60 in men, and throughout life in women. CONCLUSIONS: Current guidelines and reference values for ALT imply that subsequent diagnostics are needed for a large proportion of young men. Our data strongly suggest that age adaptation should be considered.

Detecting Receptivity for mHealth Interventions in the Natural Environment.

Just-In-Time Adaptive Intervention (JITAI) is an emerging technique with great potential to support health behavior by providing the right type and amount of support at the right time. A crucial aspect of JITAIs is properly timing the delivery of interventions, to ensure that a user is receptive and ready to process and use the support provided. Some prior works have explored the association of context and some user-specific traits on receptivity, and have built post-study machine-learning models to detect receptivity. For effective intervention delivery, however, a JITAI system needs to make in-the-moment decisions about a user's receptivity. To this end, we conducted a study in which we deployed machine-learning models to detect receptivity in the natural environment, i.e., in free-living conditions. We leveraged prior work regarding receptivity to JITAIs and deployed a chatbot-based digital coach - Ally - that provided physical-activity interventions and motivated participants to achieve their step goals. We extended the original Ally app to include two types of machine-learning model that used contextual information about a person to predict when a person is receptive: a static model that was built before the study started and remained constant for all participants and an adaptive model that continuously learned the receptivity of individual participants and updated itself as the study progressed. For comparison, we included a control model that sent intervention messages at random times. The app randomly selected a delivery model for each intervention message. We observed that the machine-learning models led up to a 40% improvement in receptivity as compared to the control model. Further, we evaluated the temporal dynamics of the different models and observed that receptivity to messages from the adaptive model increased over the course of the study.

Breath-Triggered Haptic and Acoustic Guides to Support Effortless Calm Breathing.

Stress is a common issue in today's society and can be caused by a variety of triggers in activities such as work or driving. Various negative consequences can arise of stress such as reduced job productivity, sleep disorders, or physiological diseases like depression or anxiety. A popular approach to manage stress is voluntary deep and slow breathing. However, deliberate deep breathing requires conscious attention and effort, and thus often interferes with daily activities such as working and driving. We present a system that monitors the user's breathing in real-time and provides rhythmical feedback to support effortless and unconscious slow breathing in everyday-life. Our system comprises three feedback modes: 1.) acoustic feedback, 2.) haptic feedback, and 3.) mixed feedback combining both modalities. We apply our system in a driver setting and conduct a user study with twelve participants to evaluate the effects of our intervention on users' physiology and perception. We find that acoustic and mixed guiding can reduce breathing pace without affecting focus, which suggests that subtle rhythmical feedback is a promising approach to reduce breathing pace and thus counteract stress.

From Screening to Therapy: Anti-HCV Screening and Linkage to Care in a Network of General Practitioners and a Private Gastroenterology Practice.

(1) Background: Low rates of hepatitis C virus (HCV) diagnosis and sub-optimal linkage to care constitute barriers toward eliminating the infection. In 2012/2013, we showed that HCV screening in primary care detects unknown cases. However, hepatitis C patients may not receive further diagnostics and therapy because they drop out during the referral pathway to secondary care. Thus, we used an existing network of primary care physicians and a practice of gastroenterology to investigate the pathway from screening to therapy. (2) Methods: HCV screening was prospectively included in a routine check-up of primary care physicians who cooperated regularly with a private gastroenterology practice. Anti-HCV-positive patients were referred for further specialized diagnostics and treatment if indicated. (3) Results: Seventeen primary care practices screened 1875 patients. Twelve individuals were anti-HCV-positive (0.6%), six of them reported previous antiviral HCV therapy, and one untreated patient was HCV-RNA-positive (0.05% of the population). None of the 12 anti-HCV-positive cases showed up at the private gastroenterology practice. Further clinical details of the pathway from screening to therapy could not be analyzed. (4) Conclusions: The linkage between primary and secondary care appears to be problematic in the HCV setting even among cooperating partners, but robust conclusions require larger datasets.

Establishment of a specimen panel for the decentralised technical evaluation of the sensitivity of 31 rapid diagnostic tests for SARS-CoV-2 antigen, Germany, September 2020 to April 2021.

IntroductionThe detection of SARS-CoV-2 with rapid diagnostic tests (RDT) has become an important tool to identify infected people and break infection chains. These RDT are usually based on antigen detection in a lateral flow approach.AimWe aimed to establish a comprehensive specimen panel for the decentralised technical evaluation of SARS-CoV-2 antigen rapid diagnostic tests.MethodsWhile for PCR diagnostics the validation of a PCR assay is well established, there is no common validation strategy for antigen tests, including RDT. In this proof-of-principle study we present the establishment of a panel of 50 pooled clinical specimens that cover a SARS-CoV-2 concentration range from 1.1 × 109 to 420 genome copies per mL of specimen. The panel was used to evaluate 31 RDT in up to six laboratories.ResultsOur results show that there is considerable variation in the detection limits and the clinical sensitivity of different RDT. We show that the best RDT can be applied to reliably identify infectious individuals who present with SARS-CoV-2 loads down to 106 genome copies per mL of specimen. For the identification of infected individuals with SARS-CoV-2 loads corresponding to less than 106 genome copies per mL, only three RDT showed a clinical sensitivity of more than 60%.ConclusionsSensitive RDT can be applied to identify infectious individuals with high viral loads but not to identify all infected individuals.

N-Aryl mercaptoacetamides as potential multi-target inhibitors of metallo-ß-lactamases (MBLs) and the virulence factor LasB from Pseudomonas aeruginosa.

Increasing antimicrobial resistance is evolving to be one of the major threats to public health. To reduce the selection pressure and thus to avoid a fast development of resistance, novel approaches aim to target bacterial virulence instead of growth. Another strategy is to restore the activity of antibiotics already in clinical use. This can be achieved by the inhibition of resistance factors such as metallo-ß-lactamases (MBLs). Since MBLs can cleave almost all ß-lactam antibiotics, including the "last resort" carbapenems, their inhibition is of utmost importance. Here, we report on the synthesis and in vitro evaluation of N-aryl mercaptoacetamides as inhibitors of both clinically relevant MBLs and the virulence factor LasB from Pseudomonas aeruginosa. All tested N-aryl mercaptoacetamides showed low micromolar to submicromolar activities on the tested enzymes IMP-7, NDM-1 and VIM-1. The two most promising compounds were further examined in NDM-1 expressing Klebsiella pneumoniae isolates, where they restored the full activity of imipenem. Together with their LasB-inhibitory activity in the micromolar range, this class of compounds can now serve as a starting point for a multi-target inhibitor approach against both bacterial resistance and virulence, which is unprecedented in antibacterial drug discovery.

The Practicability of the Xpert HCV Viral Load Fingerstick Point-of-Care Assay in Primary Care Settings.

Linkage to care presents one obstacle toward eliminating HCV, and the current two-step pathway (anti-HCV, followed by HCV-RNA testing) results in the loss of patients. HCV screening was tested in the primary care setting with the fingerstick Xpert HCV viral load point-of-care assay to analyze the practicability of immediate diagnosis. Anti-HCV (Cobas) and HCV-RNA (Cobas Amplicor version 2.0, only performed if anti-HCV was positive) were analyzed centrally as the gold standard. The Xpert assay was performed by 10 primary care private practices. In total, 622 patients were recruited. Five individuals (0.8%) were anti-HCV positive, and one was HCV-RNA positive. The Xpert test was valid in 546/622 (87.8%) patients. It was negative in 544 and positive in 2 cases, both of whom were anti-HCV negative. The HCV-RNA PCR and the Xpert test were both negative in 4/5 anti-HCV-positive cases, and the individual with HCV-RNA 4.5 × 106 IU/mL was not detected by the Xpert test. Primary care physicians rated the Xpert test practicability as bad, satisfactory, or good in 6%, 13%, and 81%, respectively, though 14/29 (48%) bad test ratings were assigned by a single practice. Despite adequate acceptance, interpretability and diagnostic performance in primary care settings should be further evaluated before its use in HCV screening can be recommended.

Structure-Based Design of Dual Partial Peroxisome Proliferator-Activated Receptor γ Agonists/Soluble Epoxide Hydrolase Inhibitors.

Polypharmaceutical regimens often impair treatment of patients with metabolic syndrome (MetS), a complex disease cluster, including obesity, hypertension, heart disease, and type II diabetes. Simultaneous targeting of soluble epoxide hydrolase (sEH) and peroxisome proliferator-activated receptor γ (PPARγ) synergistically counteracted MetS in various in vivo models, and dual sEH inhibitors/PPARγ agonists hold great potential to reduce the problems associated with polypharmacy in the context of MetS. However, full activation of PPARγ leads to fluid retention associated with edema and weight gain, while partial PPARγ agonists do not have these drawbacks. In this study, we designed a dual partial PPARγ agonist/sEH inhibitor using a structure-guided approach. Exhaustive structure-activity relationship studies lead to the successful optimization of the designed lead. Crystal structures of one representative compound with both targets revealed potential points for optimization. The optimized compounds exhibited favorable metabolic stability, toxicity, selectivity, and desirable activity in adipocytes and macrophages.

Prevalence of low alkaline phosphatase activity in laboratory assessment: Is hypophosphatasia an underdiagnosed disease?

BACKGROUND: Tissue-nonspecific alkaline phosphatase (TNSALP) encoded by the ALPL gene is of particular importance for bone mineralization. Mutation in the ALPL gene can lead to persistent low ALP activity resulting in the rare disease Hypophosphatasia (HPP) that is characterized by disturbed bone and dental mineralization. While severe forms are extremely rare with an estimated prevalence of 1/100.000, recent studies suggest that moderate form caused by heterozygous mutations are much more frequent with an estimated prevalence of 1/508. The purpose of this study was to estimate the prevalence of low AP levels in the population based on laboratory measurements. METHODS: In this study, the prevalence of low AP activity and elevated pyridoxal-5-phosphate (PLP) levels was analyzed in 6.918.126 measurements from 2011 to 2016 at a single laboratory in northern Germany. Only laboratory values of subjects older than 18 years of age were included. Only the first measurement was included, all repeated values were excluded. RESULTS: In total, 8.46% of the measurements of a total of 6.918.126 values showed a value < 30 U/L. 0.59% of the subjects with an ALP activity below 30 U/L had an additional PLP measurement. Here, 6.09% showed elevated pyridoxal-5-phosphate (PLP) levels. This suggest that 0.52% (1:194) of subjects show laboratory signs of HPP. CONCLUSION: These data support the genetic estimation that the prevalence of moderate forms of HPP may be significantly higher than expected. Based on these data, we recommend automatically measurement of PLP in the case of low ALP activity and a notification to the ordering physician that HPP should be included in the differential diagnosis and further exploration is recommended.