Hahn, Andreas

[["dc.bibliographiccitation.firstpage","656"],["dc.bibliographiccitation.issue","6"],["dc.bibliographiccitation.journal","Pathogens"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Tanida, Konstantin"],["dc.contributor.author","Hahn, Andreas"],["dc.contributor.author","Eberhardt, Kirsten Alexandra"],["dc.contributor.author","Tannich, Egbert"],["dc.contributor.author","Landt, Olfert"],["dc.contributor.author","Kann, Simone"],["dc.contributor.author","Feldt, Torsten"],["dc.contributor.author","Sarfo, Fred Stephen"],["dc.contributor.author","Di Cristanziano, Veronica"],["dc.contributor.author","Loderstädt, Ulrike"],["dc.contributor.author","Frickmann, Hagen"],["dc.date.accessioned","2021-08-12T07:46:03Z"],["dc.date.available","2021-08-12T07:46:03Z"],["dc.date.issued","2021"],["dc.description.abstract","Microsporidiosis is an infection predominantly occurring in immunosuppressed patients and infrequently also in travelers. This study was performed to comparatively evaluate the diagnostic accuracy of real-time PCR assays targeting microsporidia with etiological relevance in the stool of human patients in a latent class analysis-based test comparison without a reference standard with perfect accuracy. Thereby, two one-tube real-time PCR assays and two two-tube real-time PCR assays targeting Enterocytozoon bieneusi and Encephalocytozoon spp. were included in the assessment with reference stool material (20), stool samples from Ghanaian HIV-positive patients (903), and from travelers, migrants and Colombian indigenous people (416). Sensitivity of the assays ranged from 60.4% to 97.4% and specificity from 99.1% to 100% with substantial agreement according to Cohen\\’s kappa of 79.6%. Microsporidia DNA was detected in the reference material and the stool of the HIV patients but not in the stool of the travelers, migrants, and the Colombian indigenous people. Accuracy-adjusted prevalence was 5.8% (n = 78) for the study population as a whole. In conclusion, reliable detection of enteric disease-associated microsporidia in stool samples by real-time PCR could be demonstrated, but sensitivity between the compared microsporidia-specific real-time PCR assays varied."],["dc.description.abstract","Microsporidiosis is an infection predominantly occurring in immunosuppressed patients and infrequently also in travelers. This study was performed to comparatively evaluate the diagnostic accuracy of real-time PCR assays targeting microsporidia with etiological relevance in the stool of human patients in a latent class analysis-based test comparison without a reference standard with perfect accuracy. Thereby, two one-tube real-time PCR assays and two two-tube real-time PCR assays targeting Enterocytozoon bieneusi and Encephalocytozoon spp. were included in the assessment with reference stool material (20), stool samples from Ghanaian HIV-positive patients (903), and from travelers, migrants and Colombian indigenous people (416). Sensitivity of the assays ranged from 60.4% to 97.4% and specificity from 99.1% to 100% with substantial agreement according to Cohen’s kappa of 79.6%. Microsporidia DNA was detected in the reference material and the stool of the HIV patients but not in the stool of the travelers, migrants, and the Colombian indigenous people. Accuracy-adjusted prevalence was 5.8% (n = 78) for the study population as a whole. In conclusion, reliable detection of enteric disease-associated microsporidia in stool samples by real-time PCR could be demonstrated, but sensitivity between the compared microsporidia-specific real-time PCR assays varied."],["dc.description.sponsorship","Bundesministerium der Verteidigung"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.3390/pathogens10060656"],["dc.identifier.pii","pathogens10060656"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/88607"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-448"],["dc.relation.eissn","2076-0817"],["dc.relation.haserratum","/handle/2/105036"],["dc.relation.orgunit","Institut für Krankenhaushygiene und Infektiologie"],["dc.rights","CC BY 4.0"],["dc.title","Comparative Assessment of In-House Real-Time PCRs Targeting Enteric Disease-Associated Microsporidia in Human Stool Samples"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","929"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Antibiotics"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Hahn, Andreas"],["dc.contributor.author","Frickmann, Hagen"],["dc.contributor.author","Loderstädt, Ulrike"],["dc.date.accessioned","2021-10-01T09:58:21Z"],["dc.date.available","2021-10-01T09:58:21Z"],["dc.date.issued","2021"],["dc.description.abstract","Prescribed antibiotic treatments which do not match the therapeutic requirements of potentially co-existing undetected sexually transmitted infections (STIs) can facilitate the selection of antibiotic-drug-resistant clones. To reduce this risk, this modelling assessed the potential applicability of reliable rapid molecular test assays targeting bacterial STI prior to the prescription of antibiotic drugs. The modelling was based on the prevalence of three bacterial STIs in German heterosexual and men-having-sex-with-men (MSM) populations, as well as on reported test characteristics of respective assays. In the case of the application of rapid molecular STI assays for screening, the numbers needed to test in order to correctly identify any of the included bacterial STIs ranged from 103 to 104 for the heterosexual population and from 5 to 14 for the MSM population. The number needed to harm—defined as getting a false negative result for any of the STIs and a false positive signal for another one, potentially leading to an even more inappropriate adaptation of antibiotic therapy than without any STI screening—was at least 208,995 for the heterosexuals and 16,977 for the MSM. Therefore, the screening approach may indeed be suitable to avoid unnecessary selective pressure on bacterial causes of sexually transmitted infections."],["dc.description.abstract","Prescribed antibiotic treatments which do not match the therapeutic requirements of potentially co-existing undetected sexually transmitted infections (STIs) can facilitate the selection of antibiotic-drug-resistant clones. To reduce this risk, this modelling assessed the potential applicability of reliable rapid molecular test assays targeting bacterial STI prior to the prescription of antibiotic drugs. The modelling was based on the prevalence of three bacterial STIs in German heterosexual and men-having-sex-with-men (MSM) populations, as well as on reported test characteristics of respective assays. In the case of the application of rapid molecular STI assays for screening, the numbers needed to test in order to correctly identify any of the included bacterial STIs ranged from 103 to 104 for the heterosexual population and from 5 to 14 for the MSM population. The number needed to harm—defined as getting a false negative result for any of the STIs and a false positive signal for another one, potentially leading to an even more inappropriate adaptation of antibiotic therapy than without any STI screening—was at least 208,995 for the heterosexuals and 16,977 for the MSM. Therefore, the screening approach may indeed be suitable to avoid unnecessary selective pressure on bacterial causes of sexually transmitted infections."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.3390/antibiotics10080929"],["dc.identifier.pii","antibiotics10080929"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/90046"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-469"],["dc.relation.eissn","2079-6382"],["dc.rights","CC BY 4.0"],["dc.title","Testing as Prevention of Resistance in Bacteria Causing Sexually Transmitted Infections—A Population-Based Model for Germany"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","188"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Pathogens"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Hoffmann, Tanja"],["dc.contributor.author","Hahn, Andreas"],["dc.contributor.author","Verweij, Jaco J."],["dc.contributor.author","Leboulle, Gérard"],["dc.contributor.author","Landt, Olfert"],["dc.contributor.author","Strube, Christina"],["dc.contributor.author","Kann, Simone"],["dc.contributor.author","Dekker, Denise"],["dc.contributor.author","May, Jürgen"],["dc.contributor.author","Frickmann, Hagen"],["dc.contributor.author","Loderstädt, Ulrike"],["dc.date.accessioned","2021-04-14T08:29:37Z"],["dc.date.available","2021-04-14T08:29:37Z"],["dc.date.issued","2021"],["dc.description.sponsorship","Bundesministerium der Verteidigung"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.3390/pathogens10020188"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/82947"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.relation.eissn","2076-0817"],["dc.relation.orgunit","Institut für Krankenhaushygiene und Infektiologie"],["dc.rights","CC BY 4.0"],["dc.title","Differing Effects of Standard and Harsh Nucleic Acid Extraction Procedures on Diagnostic Helminth Real-Time PCRs Applied to Human Stool Samples"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1131"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Pathogens"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Weinreich, Felix"],["dc.contributor.author","Hahn, Andreas"],["dc.contributor.author","Eberhardt, Kirsten Alexandra"],["dc.contributor.author","Feldt, Torsten"],["dc.contributor.author","Sarfo, Fred Stephen"],["dc.contributor.author","Di Cristanziano, Veronica"],["dc.contributor.author","Frickmann, Hagen"],["dc.contributor.author","Loderstädt, Ulrike"],["dc.date.accessioned","2021-12-01T09:24:07Z"],["dc.date.available","2021-12-01T09:24:07Z"],["dc.date.issued","2021"],["dc.description.abstract","As qualified microscopy of enteric parasitoses as defined by high diagnostic accuracy is difficult to maintain in non-endemic areas due to scarce opportunities for practicing with positive sample materials, molecular diagnostic options provide less investigator-dependent alternatives. Here, we compared three molecular targets for the real-time PCR-based detection of Cryptosporidium spp. From a population of 1000 individuals comprising both Ghanaian HIV (human immunodeficiency virus) patients and military returnees after deployment in the tropics, stool samples were assessed for Cryptosporidium spp. by real-time PCR targeting the small subunit ribosomal RNA (SSU rRNA) gene, the Cryptosporidium oocyst wall (COWP) gene, and the DnaJ-like protein gene (DnaJ), respectively. In declining order, sensitivity of 100% for the SSU rRNA gene PCR, 90.0% for the COWP PCR and 88.8% for the DnaJ PCR, respectively, as well as specificity of 99.6% for the COWP PCR and 96.9% for both the SSU rRNA gene PCR and the DnaJ PCR, respectively, were recorded. Substantial agreement (kappa value 0.663) between the three assays was observed. Further, an accuracy-adjusted Cryptosporidium spp. prevalence of 6.0% was calculated for the study population. In conclusion, none of the assessed real-time PCR assays were associated with perfect test accuracy. However, a combination of highly sensitive SSU rRNA gene PCR for screening purposes and more specific COWP PCR for confirmatory testing should allow reliable diagnosis of Cryptosporidium spp. in stool samples even in low prevalence settings."],["dc.description.abstract","As qualified microscopy of enteric parasitoses as defined by high diagnostic accuracy is difficult to maintain in non-endemic areas due to scarce opportunities for practicing with positive sample materials, molecular diagnostic options provide less investigator-dependent alternatives. Here, we compared three molecular targets for the real-time PCR-based detection of Cryptosporidium spp. From a population of 1000 individuals comprising both Ghanaian HIV (human immunodeficiency virus) patients and military returnees after deployment in the tropics, stool samples were assessed for Cryptosporidium spp. by real-time PCR targeting the small subunit ribosomal RNA (SSU rRNA) gene, the Cryptosporidium oocyst wall (COWP) gene, and the DnaJ-like protein gene (DnaJ), respectively. In declining order, sensitivity of 100% for the SSU rRNA gene PCR, 90.0% for the COWP PCR and 88.8% for the DnaJ PCR, respectively, as well as specificity of 99.6% for the COWP PCR and 96.9% for both the SSU rRNA gene PCR and the DnaJ PCR, respectively, were recorded. Substantial agreement (kappa value 0.663) between the three assays was observed. Further, an accuracy-adjusted Cryptosporidium spp. prevalence of 6.0% was calculated for the study population. In conclusion, none of the assessed real-time PCR assays were associated with perfect test accuracy. However, a combination of highly sensitive SSU rRNA gene PCR for screening purposes and more specific COWP PCR for confirmatory testing should allow reliable diagnosis of Cryptosporidium spp. in stool samples even in low prevalence settings."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.3390/pathogens10091131"],["dc.identifier.pii","pathogens10091131"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/94849"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-478"],["dc.relation.eissn","2076-0817"],["dc.relation.orgunit","Institut für Krankenhaushygiene und Infektiologie"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0/"],["dc.title","Comparison of Three Real-Time PCR Assays Targeting the SSU rRNA Gene, the COWP Gene and the DnaJ-Like Protein Gene for the Diagnosis of Cryptosporidium spp. in Stool Samples"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","826"],["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","Pathogens"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Tanida, Konstantin"],["dc.contributor.author","Balczun, Carsten"],["dc.contributor.author","Hahn, Andreas"],["dc.contributor.author","Veit, Alexandra"],["dc.contributor.author","Nickel, Beatrice"],["dc.contributor.author","Poppert, Sven"],["dc.contributor.author","Scheid, Patrick Leander"],["dc.contributor.author","Hagen, Ralf Matthias"],["dc.contributor.author","Frickmann, Hagen"],["dc.contributor.author","Tannich, Egbert"],["dc.contributor.author","Loderstädt, Ulrike"],["dc.date.accessioned","2021-08-12T07:46:04Z"],["dc.date.available","2021-08-12T07:46:04Z"],["dc.date.issued","2021"],["dc.description.abstract","To perform PCR from serum for the diagnosis of visceral leishmaniasis is convenient and much less invasive than the examination of deeper compartments such as bone marrow. We compared three Leishmania-specific real-time PCRs with three different molecular targets (kinetoplast DNA, the small subunit-ribosomal RNA-(ssrRNA-)gene, the glucose-6-phosphate isomerase-(gpi-)gene) regarding their sensitivity and specificity in human serum. Residual sera from previous diagnostic assessments at the German National Reference Center for Tropical Pathogens Bernhard Nocht Institute for Tropical Medicine Hamburg and the Swiss Tropical and Public Health Institute were used. The sensitivities of kinetoplast DNA-PCR, ssrRNA-gene PCR, and gpi-PCR were 93.3%, 73.3%, and 33.3%, respectively, with 15 initial serum samples from visceral leishmaniasis patients, as well as 9.1%, 9.1%, and 0.0%, respectively, with 11 follow-up serum samples taken at various time points following anti-leishmanial therapy. Specificity was 100.0% in all assays as recorded with 1.137 serum samples from deployed soldiers and migrants without clinical suspicion of visceral leishmaniasis. Kinetoplast-DNA PCR from serum was confirmed as a sensitive and specific approach for the diagnosis of visceral leishmaniasis. The results also indicate the suitability of serum PCR for diagnostic follow-up after therapy, in particular regarding therapeutic failure in case of persisting positive PCR results."],["dc.description.abstract","To perform PCR from serum for the diagnosis of visceral leishmaniasis is convenient and much less invasive than the examination of deeper compartments such as bone marrow. We compared three Leishmania-specific real-time PCRs with three different molecular targets (kinetoplast DNA, the small subunit-ribosomal RNA-(ssrRNA-)gene, the glucose-6-phosphate isomerase-(gpi-)gene) regarding their sensitivity and specificity in human serum. Residual sera from previous diagnostic assessments at the German National Reference Center for Tropical Pathogens Bernhard Nocht Institute for Tropical Medicine Hamburg and the Swiss Tropical and Public Health Institute were used. The sensitivities of kinetoplast DNA-PCR, ssrRNA-gene PCR, and gpi-PCR were 93.3%, 73.3%, and 33.3%, respectively, with 15 initial serum samples from visceral leishmaniasis patients, as well as 9.1%, 9.1%, and 0.0%, respectively, with 11 follow-up serum samples taken at various time points following anti-leishmanial therapy. Specificity was 100.0% in all assays as recorded with 1.137 serum samples from deployed soldiers and migrants without clinical suspicion of visceral leishmaniasis. Kinetoplast-DNA PCR from serum was confirmed as a sensitive and specific approach for the diagnosis of visceral leishmaniasis. The results also indicate the suitability of serum PCR for diagnostic follow-up after therapy, in particular regarding therapeutic failure in case of persisting positive PCR results."],["dc.description.sponsorship","Bundesministerium der Verteidigung"],["dc.identifier.doi","10.3390/pathogens10070826"],["dc.identifier.pii","pathogens10070826"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/88609"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-448"],["dc.publisher","MDPI"],["dc.relation.eissn","2076-0817"],["dc.rights","https://creativecommons.org/licenses/by/4.0/"],["dc.title","Comparison of Three In-House Real PCR Assays Targeting Kinetoplast DNA, the Small Subunit Ribosomal RNA Gene and the Glucose-6-Phosphate Isomerase Gene for the Detection of Leishmania spp. in Human Serum"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1053"],["dc.bibliographiccitation.issue","8"],["dc.bibliographiccitation.journal","Pathogens"],["dc.bibliographiccitation.volume","10"],["dc.contributor.author","Blohm, Martin"],["dc.contributor.author","Hahn, Andreas"],["dc.contributor.author","Hagen, Ralf Matthias"],["dc.contributor.author","Eberhardt, Kirsten Alexandra"],["dc.contributor.author","Rohde, Holger"],["dc.contributor.author","Leboulle, Gérard"],["dc.contributor.author","Feldt, Torsten"],["dc.contributor.author","Sarfo, Fred Stephen"],["dc.contributor.author","Di Cristanziano, Veronica"],["dc.contributor.author","Frickmann, Hagen"],["dc.contributor.author","Loderstädt, Ulrike"],["dc.date.accessioned","2021-10-01T09:58:31Z"],["dc.date.available","2021-10-01T09:58:31Z"],["dc.date.issued","2021"],["dc.description.abstract","Cystoisospora (C.) belli is a coccidian parasite associated with acute or chronic gastroenteritis in immunocompromised patients. Dissatisfactory sensitivity of microscopy as the diagnostic standard approach has been described. Here, we comparatively evaluated two real-time PCRs targeting ribosomal RNA gene sequences of C. belli in stool in a test comparison without a reference standard applying latent class analysis. Therefore, 1000 stool samples from Ghanaian HIV (human immunodeficiency virus) patients (n = 905) as well as military returnees from the tropics (n = 95) were assessed by both assays in parallel. After the exclusion of 33 samples showing PCR inhibition, 29 and 33 positive results were recorded with the 5.8S rRNA gene/ITS-2 sequence PCR and the ITS-2 sequence PCR, respectively, resulting in an accuracy-adjusted prevalence of 3.2%. Nearly perfect agreement between both assays was indicated by Fleiss’ kappa of 0.933 with sensitivity and specificity of 92.8% and 100% as well as 100% and 99.8% for the 5.8S rRNA gene/ITS-2 sequence PCR and the ITS-2 sequence PCR, respectively. Both assays proved to be suitable for the diagnosis of C. belli in human stool samples with slightly better sensitivity of the ITS-2 sequence assay, while the 5.8S rRNA gene/ITS-2 sequence PCR may be considered for confirmatory testing."],["dc.description.abstract","Cystoisospora (C.) belli is a coccidian parasite associated with acute or chronic gastroenteritis in immunocompromised patients. Dissatisfactory sensitivity of microscopy as the diagnostic standard approach has been described. Here, we comparatively evaluated two real-time PCRs targeting ribosomal RNA gene sequences of C. belli in stool in a test comparison without a reference standard applying latent class analysis. Therefore, 1000 stool samples from Ghanaian HIV (human immunodeficiency virus) patients (n = 905) as well as military returnees from the tropics (n = 95) were assessed by both assays in parallel. After the exclusion of 33 samples showing PCR inhibition, 29 and 33 positive results were recorded with the 5.8S rRNA gene/ITS-2 sequence PCR and the ITS-2 sequence PCR, respectively, resulting in an accuracy-adjusted prevalence of 3.2%. Nearly perfect agreement between both assays was indicated by Fleiss’ kappa of 0.933 with sensitivity and specificity of 92.8% and 100% as well as 100% and 99.8% for the 5.8S rRNA gene/ITS-2 sequence PCR and the ITS-2 sequence PCR, respectively. Both assays proved to be suitable for the diagnosis of C. belli in human stool samples with slightly better sensitivity of the ITS-2 sequence assay, while the 5.8S rRNA gene/ITS-2 sequence PCR may be considered for confirmatory testing."],["dc.description.sponsorship","Bundesministerium der Verteidigung"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.3390/pathogens10081053"],["dc.identifier.pii","pathogens10081053"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/90079"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-469"],["dc.relation.eissn","2076-0817"],["dc.relation.orgunit","Institut für Krankenhaushygiene und Infektiologie"],["dc.rights","CC BY 4.0"],["dc.title","Comparison of Two Real-Time PCR Assays Targeting Ribosomal Sequences for the Identification of Cystoisospora belli in Human Stool Samples"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1007"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Diagnostics"],["dc.bibliographiccitation.volume","12"],["dc.contributor.affiliation","Weinreich, Felix; 1Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, 20359 Hamburg, Germany; felixweinreich@bundeswehr.org (F.W.); frickmann@bnitm.de (H.F.)"],["dc.contributor.affiliation","Hahn, Andreas; 2Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany; andreas.hahn@uni-rostock.de (A.H.); thomas.koeller@med.uni-rostock.de (T.K.); philipp.warnke@med.uni-rostock.de (P.W.)"],["dc.contributor.affiliation","Eberhardt, Kirsten Alexandra; 3Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine Hamburg & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20359 Hamburg, Germany; k.eberhardt@bnitm.de"],["dc.contributor.affiliation","Kann, Simone; 4Medical Mission Institute, 97074 Würzburg, Germany; simone_kann@hotmail.com"],["dc.contributor.affiliation","Köller, Thomas; 2Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany; andreas.hahn@uni-rostock.de (A.H.); thomas.koeller@med.uni-rostock.de (T.K.); philipp.warnke@med.uni-rostock.de (P.W.)"],["dc.contributor.affiliation","Warnke, Philipp; 2Institute for Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany; andreas.hahn@uni-rostock.de (A.H.); thomas.koeller@med.uni-rostock.de (T.K.); philipp.warnke@med.uni-rostock.de (P.W.)"],["dc.contributor.affiliation","Dupke, Susann; 5Centre for Biological Threats and Special Pathogens/Highly Pathogenic Microorganisms, Robert Koch Institute, 13353 Berlin, Germany; dupkes@rki.de"],["dc.contributor.affiliation","Dekker, Denise; 6Infectious Disease Epidemiology Department, Bernhard Nocht Institute for Tropical Medicine Hamburg, 20259 Hamburg, Germany; dekker@bnitm.de (D.D.); may@bnitm.de (J.M.)"],["dc.contributor.affiliation","May, Jürgen; 6Infectious Disease Epidemiology Department, Bernhard Nocht Institute for Tropical Medicine Hamburg, 20259 Hamburg, Germany; dekker@bnitm.de (D.D.); may@bnitm.de (J.M.)"],["dc.contributor.affiliation","Frickmann, Hagen; 1Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, 20359 Hamburg, Germany; felixweinreich@bundeswehr.org (F.W.); frickmann@bnitm.de (H.F.)"],["dc.contributor.affiliation","Loderstädt, Ulrike; 9Department of Hospital Hygiene & Infectious Diseases, University Medicine Göttingen, 37075 Göttingen, Germany"],["dc.contributor.author","Weinreich, Felix"],["dc.contributor.author","Hahn, Andreas"],["dc.contributor.author","Eberhardt, Kirsten Alexandra"],["dc.contributor.author","Kann, Simone"],["dc.contributor.author","Köller, Thomas"],["dc.contributor.author","Warnke, Philipp"],["dc.contributor.author","Dupke, Susann"],["dc.contributor.author","Dekker, Denise"],["dc.contributor.author","May, Jürgen"],["dc.contributor.author","Frickmann, Hagen"],["dc.contributor.author","Loderstädt, Ulrike"],["dc.date.accessioned","2022-05-02T08:09:35Z"],["dc.date.available","2022-05-02T08:09:35Z"],["dc.date.issued","2022"],["dc.date.updated","2022-05-05T12:51:57Z"],["dc.description.abstract","Prior to the implementation of new diagnostic techniques, a thorough evaluation is mandatory in order to ensure diagnostic reliability. If positive samples are scarcely available, however, such evaluations can be difficult to perform. Here, we evaluated four SeeGene Allplex real-time PCR assays amplifying a total of 28 bacteria, microsporidal and parasitic nucleic acid sequence targets in human stool samples in a multicentric approach. In the assessments with strongly positive samples, sensitivity values ranging between 13% and 100% were recorded for bacteria, between 0% and 100% for protozoa and between 7% and 100% for helminths and microsporidia; for the weakly positive samples, the recorded sensitivity values for bacteria ranged from 0% to 100%; for protozoa, from 0% to 40%; and for helminths and microsporidia, from 0% to 53%. For bacteria, the recorded specificity was in the range between 87% and 100%, while a specificity of 100% was recorded for all assessed PCRs targeting parasites and microsporidia. The intra- and inter-assay variations were generally low. Specifically for some helminth species, the sensitivity could be drastically increased by applying manual nucleic acid extraction instead of the manufacturer-recommended automatic procedure, while such effects were less obvious for the bacteria and protozoa. In summary, the testing with the chosen positive control samples showed varying degrees of discordance between the evaluated Allplex assays and the applied in-house reference assays associated with higher cycle threshold values in the Allplex assays, suggesting that samples with very low pathogen densities might be missed. As the targeted species can occur as harmless colonizers in the gut of individuals in high-endemicity settings as well, future studies should aim at assessing the clinical relevance of the latter hint."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2022"],["dc.identifier.doi","10.3390/diagnostics12041007"],["dc.identifier.pii","diagnostics12041007"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/107414"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-561"],["dc.relation.eissn","2075-4418"],["dc.rights","CC BY 4.0"],["dc.title","Multicentric Evaluation of SeeGene Allplex Real-Time PCR Assays Targeting 28 Bacterial, Microsporidal and Parasitic Nucleic Acid Sequences in Human Stool Samples"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","7"],["dc.bibliographiccitation.journal","Microorganisms"],["dc.bibliographiccitation.volume","10"],["dc.contributor.affiliation","Weinreich, Felix; 1Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, 20359 Hamburg, Germany; felixweinreich@bundeswehr.org (F.W.); frickmann@bnitm.de (H.F.)"],["dc.contributor.affiliation","Hahn, Andreas; 2Department of Medical Microbiology, Virology and Hygiene, University Medicine Rostock, 18057 Rostock, Germany; andreas.hahn@uni-rostock.de"],["dc.contributor.affiliation","Eberhardt, Kirsten Alexandra; 3Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine & I. Department of Medicine, University Medical Center Hamburg-Eppendorf, 20251 Hamburg, Germany; k.eberhardt@bnitm.de"],["dc.contributor.affiliation","Kann, Simone; 5Medmissio, 97074 Würzburg, Germany; simone.kann@medmissio.de"],["dc.contributor.affiliation","Feldt, Torsten; 6Department of Gastroenterology, Hepatology and Infectious Diseases, University Medical Center Düsseldorf, 40225 Düsseldorf, Germany; torsten.feldt@med.uni-duesseldorf.de"],["dc.contributor.affiliation","Sarfo, Fred Stephen; 7Department of Medicine, Kwame Nkrumah University of Science and Technology, Kumasi AK-4944, Ghana; stephensarfo78@gmail.com"],["dc.contributor.affiliation","Di Cristanziano, Veronica; 8Institute of Virology, Faculty of Medicine and University Hospital of Cologne, University of Cologne, 50935 Cologne, Germany; veronica.di-cristanziano@uk-koeln.de"],["dc.contributor.affiliation","Frickmann, Hagen; 1Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg, 20359 Hamburg, Germany; felixweinreich@bundeswehr.org (F.W.); frickmann@bnitm.de (H.F.)"],["dc.contributor.affiliation","Loderstädt, Ulrike; 9Department of Hospital Hygiene & Infectious Diseases, University Medicine Göttingen, 37075 Göttingen, Germany"],["dc.contributor.author","Weinreich, Felix"],["dc.contributor.author","Hahn, Andreas"],["dc.contributor.author","Eberhardt, Kirsten Alexandra"],["dc.contributor.author","Kann, Simone"],["dc.contributor.author","Feldt, Torsten"],["dc.contributor.author","Sarfo, Fred Stephen"],["dc.contributor.author","Di Cristanziano, Veronica"],["dc.contributor.author","Frickmann, Hagen"],["dc.contributor.author","Loderstädt, Ulrike"],["dc.date.accessioned","2022-07-11T06:52:41Z"],["dc.date.available","2022-07-11T06:52:41Z"],["dc.date.issued","2022-06-28"],["dc.date.updated","2022-07-08T11:04:06Z"],["dc.description.abstract","Due to superior sensitivity compared to traditional microscopy, real-time PCR has been well established for the diagnosis of Giardia duodenalis in human stool samples. In this study, screening real-time PCRs for different target genes of G. duodenalis, i.e., the 18S rRNA gene, the gdh (glutamate dehydrogenase) gene and the bg (beta-giardin) gene, were comparatively assessed next to various real-time PCR assays for the discrimination of the assemblages A and B of G. duodenalis targeting the bg gene with and without locked nucleic acid–containing probes as well as the tpi (triose phosphate isomerase) gene. The screening PCRs were assessed by including 872 non-preselected samples with a high pre-test probability for G. duodenalis in the statistical analysis, while 53 G. duodenalis-positive samples as indicated by at least two screening PCRs were finally included in the assessment of the assemblage-specific PCRs. For the screening PCRs, sensitivity estimated with latent class analysis (LCA) ranged from 17.5% to 100%, specificity from 92.3% to 100% with an accuracy-adjusted prevalence of 7.2% for G. duodenalis within the non-preselected sample collection. In detail, sensitivity and specificity were 100% and 100% for the 18S rRNA gene-specific assay, 17.5% and 92.3% for the gdh gene-specific assay, and 31.7% and 100% for the bg gene-specific assay, respectively. Agreement kappa was slight with only 15.5%. For the assemblage-specific PCRs, estimated sensitivity ranged from 82.1% to 100%, specificity from 84.0% to 100% with nearly perfect agreement kappa of 90.1% for assemblage A and yet substantial agreement of 74.8% for assemblage B. In detail for assemblage A, sensitivity and specificity were 100% and 100% for the bg gene-specific assay without locked nucleic acids (LNA) as well as 100% and 97.8% for both the bg gene-specific assay with LNA and the tri gene-specific assay, respectively. For assemblage B, sensitivity and specificity were 100% and 100% for the bg gene-specific assay without LNA, 96.4% and 84.0% for the bg gene-specific assay with LNA, and 82.1% and 100% for the tri gene-specific assay, respectively. Within the assessed sample collection, the observed proportion comprised 15.1% G. duodenalis assemblage A, 52.8% G. duodenalis assemblage B and 32.1% non-resolved assemblages. Only little differences were observed regarding the cycle threshold (Ct) values when comparing the assays. In conclusion, best diagnostic accuracy was shown for an 18S rRNA gene-specific screening assay for G. duodenalis and for a differentiation assay discriminating the G. duodenalis assemblages A and B by targeting the bg gene with probes not containing locked nucleic acids. By adding additional highly specific competitor assays for confirmation testing, diagnostic specificity can be further increased on the cost of sensitivity if optimized specificity is desired."],["dc.description.sponsorship","the German Ministry of Defense (MoD)"],["dc.description.sponsorship","Open-Access-Publikationsfonds 2022"],["dc.identifier.doi","10.3390/microorganisms10071310"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/112415"],["dc.language.iso","en"],["dc.relation.eissn","2076-2607"],["dc.rights","CC BY 4.0"],["dc.title","Comparative Evaluation of Real-Time Screening PCR Assays for Giardia duodenalis and of Assays Discriminating the Assemblages A and B"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","2079"],["dc.bibliographiccitation.issue","11"],["dc.bibliographiccitation.journal","Diagnostics"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Hahn, Andreas"],["dc.contributor.author","Frickmann, Hagen"],["dc.contributor.author","Loderstädt, Ulrike"],["dc.date.accessioned","2022-01-11T14:07:51Z"],["dc.date.available","2022-01-11T14:07:51Z"],["dc.date.issued","2021"],["dc.description.abstract","In clinical studies, case definitions are usually designed to optimally match the desired clinical state, because lacking specificity is associated with a risk of bias regarding the study outcome. In preventive medicine, however, high sensitivity is sometimes considered as more critical in order not to overlook infectious individuals, because the latter may be associated with ongoing spread of a transmittable disease. Accordingly, this work was focused on a theoretical model on how the sensitivity of case definitions can be optimized by adding clinical symptoms to diagnostic results for preventive purposes, if the associated reduction in specificity is considered as acceptable. The model was exemplified with an analysis on whether and in how far exposure risk can be reduced by the inclusion of observable symptoms during seroconversion syndrome in case of rapid diagnostic test-based prevention of sexual HIV transmission. The approach provided a high level of safety (negative predictive values close to 1) for the price of a considerably number of false positives (positive predictive values < 0.01 for some subpopulations). When applying such a sensitivity-optimized screening as a “diagnostics as prevention” strategy, the advantages of excellent negative predictive values need to be cautiously balanced against potential undesirable consequences of low positive predictive values."],["dc.description.abstract","In clinical studies, case definitions are usually designed to optimally match the desired clinical state, because lacking specificity is associated with a risk of bias regarding the study outcome. In preventive medicine, however, high sensitivity is sometimes considered as more critical in order not to overlook infectious individuals, because the latter may be associated with ongoing spread of a transmittable disease. Accordingly, this work was focused on a theoretical model on how the sensitivity of case definitions can be optimized by adding clinical symptoms to diagnostic results for preventive purposes, if the associated reduction in specificity is considered as acceptable. The model was exemplified with an analysis on whether and in how far exposure risk can be reduced by the inclusion of observable symptoms during seroconversion syndrome in case of rapid diagnostic test-based prevention of sexual HIV transmission. The approach provided a high level of safety (negative predictive values close to 1) for the price of a considerably number of false positives (positive predictive values < 0.01 for some subpopulations). When applying such a sensitivity-optimized screening as a “diagnostics as prevention” strategy, the advantages of excellent negative predictive values need to be cautiously balanced against potential undesirable consequences of low positive predictive values."],["dc.description.sponsorship","Open-Access-Publikationsfonds 2021"],["dc.identifier.doi","10.3390/diagnostics11112079"],["dc.identifier.pii","diagnostics11112079"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/97879"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-507"],["dc.relation.eissn","2075-4418"],["dc.relation.orgunit","Institut für Krankenhaushygiene und Infektiologie"],["dc.rights","CC BY 4.0"],["dc.rights.uri","https://creativecommons.org/licenses/by/4.0/"],["dc.title","Optimization of Case Definitions for Sensitivity as a Preventive Strategy—A Modelling Exemplified with Rapid Diagnostic Test-Based Prevention of Sexual HIV Transmission"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]