Katharina Weizsäcker
Charité
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Featured researches published by Katharina Weizsäcker.
Journal of Antimicrobial Chemotherapy | 2014
Luisa A. Denkel; Frank Schwab; Axel Kola; Rasmus Leistner; Lars Garten; Katharina Weizsäcker; Christine Geffers; Petra Gastmeier; Brar Piening
OBJECTIVES This study aimed to determine the prevalence of and risk factors for colonization with extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBL-E) and methicillin-resistant Staphylococcus aureus (MRSA) in very low birth weight (VLBW; <1500 g) infants and their mothers. METHODS This investigation was conducted in the perinatal centre at the Charité Berlin between May 2012 and June 2013. VLBW infants and their mothers were screened for colonization with ESBL-E and MRSA. Demographic and clinical data were obtained from the German nationwide surveillance system for nosocomial infections in VLBW infants (NEO-KISS) and used to perform univariate and multivariate analyses. RESULTS Of 209 VLBW infants, 12 (5.7%) were colonized with ESBL-E. Eighteen of 209 (8.6%) ESBL-E-tested neonates were related to an ESBL-E-positive mother. Univariate analysis, strain typing and multivariate analysis (OR 7.4, 95% CI 2.1-26.7, P = 0.002) identified an ESBL-E-positive mother and maternal-neonatal transmission as a main source of colonization. The prevalence of MRSA was 2.3% (5 of 221) among VLBW infants. One of the 221 (0.5%) MRSA-tested neonates was related to an MRSA-positive mother. No risk factors for transmission of MRSA could be detected in this study. CONCLUSIONS Our study demonstrated that maternal-neonatal transmission of ESBL-E from mother to child is an important risk factor for colonization of VLBW infants. As a consequence, routine ESBL-E screening of neonates and mothers should be considered as a means of reducing neonatal morbidity and mortality.
AIDS | 2013
Angela Colbers; David Hawkins; Andrea Gingelmaier; Kabamba Kabeya; Jürgen K. Rockstroh; Christoph Wyen; Katharina Weizsäcker; S.T. Sadiq; J. Ivanovic; Carlo Giaquinto; Graham Taylor; José Moltó; David M. Burger
Objective:To describe the pharmacokinetics of tenofovir and emtricitabine in the third trimester of pregnant HIV-infected women and at postpartum. Design:A nonrandomized, open-label, multicentre phase IV study in HIV-infected pregnant women recruited from HIV treatment centres in Europe. Methods:HIV-infected pregnant women treated with the nucleotide/nucleoside analogue reverse transcriptase inhibitors (NRTIs) tenofovir disoproxil fumarate (TDF 300 mg; equivalent to 245 mg tenofovir disoproxil) and/or emtricitabine (FTC 200 mg) were included in the study. Twenty-four-hour pharmacokinetic curves were recorded in the third trimester (preferably week 33) and postpartum (preferably week 4–6). Collection of a cord blood sample and maternal sample at delivery was optional. Pharmacokinetic parameters were calculated using WinNonlin software version 5.3. Statistical analysis was conducted using SPSS version 16.0. Results:Thirty-four women were included in the analysis. Geometric mean ratios of third trimester vs. postpartum [90% confidence interval (CI)] were 0.77 (0.71–0.83) for TDF area under the curve (AUC0–24 h); 0.81 (0.68–0.96) for TDF Cmax and 0.79 (0.70–0.90) for TDF C24 h and 0.75 (0.68–0.82) for FTC AUC0–24 h; and 0.87 (0.77–0.99) for FTC Cmax and 0.77 (0.52–1.12) for FTC C24 h. The viral load close to delivery was less than 200 copies/ml in all but one patient, the average gestational age at delivery was 38 weeks. All children were tested HIV-negative and no congenital abnormalities were reported. Conclusion:Although pharmacokinetic exposure of the NRTIs TDF and FTC during pregnancy is approximately 25% lower, this was not associated with virological failure in this study and did not result in mother-to-child transmission.
Journal of Antimicrobial Chemotherapy | 2015
Angela Colbers; José Moltó; J. Ivanovic; Kabamba Kabeya; David Hawkins; Andrea Gingelmaier; Graham Taylor; Katharina Weizsäcker; S Tariq Sadiq; Marchina E. van der Ende; Carlo Giaquinto; David M. Burger; A.J.A.M. van der Ven; Adilia Warris; Jeannine F. J. B. Nellen; Fyona Lyons; Julien Lambert; Annette Haberl; Gerd Faetkenheuer; Christoph Wyen; Jürgen K. Rockstroh; Carolynne Schwarze-Zander; Yvonne Gilleece; Chris Wood
OBJECTIVES To describe the pharmacokinetics of darunavir in pregnant HIV-infected women in the third trimester and post-partum. PATIENTS AND METHODS This was a non-randomized, open-label, multicentre, Phase IV study in HIV-infected pregnant women recruited from HIV treatment centres in Europe. HIV-infected pregnant women treated with darunavir (800/100 mg once daily or 600/100 mg twice daily) as part of their combination ART were included. Pharmacokinetic curves were recorded in the third trimester and post-partum. A cord blood sample and maternal sample were collected. The study is registered at ClinicalTrials.gov under number NCT00825929. RESULTS Twenty-four women were included in the analysis [darunavir/ritonavir: 600/100 mg twice daily (n=6); 800/100 mg once daily (n=17); and 600/100 mg once daily (n=1)]. Geometric mean ratios of third trimester versus post-partum (90% CI) were 0.78 (0.60-1.00) for total darunavir AUC0-tau after 600/100 mg twice-daily dosing and 0.67 (0.56-0.82) for total darunavir AUC0-tau after 800/100 mg once-daily dosing. The unbound fraction of darunavir was not different during pregnancy (12%) compared with post-partum (10%). The median (range) ratio of darunavir cord blood/maternal blood was 0.13 (0.08-0.35). Viral load close to delivery was <300 copies/mL in all but two patients. All children were tested HIV-negative and no congenital abnormalities were reported. CONCLUSIONS Darunavir AUC and Cmax were substantially decreased in pregnancy for both darunavir/ritonavir regimens. This decrease in exposure did not result in mother-to-child transmission. For antiretroviral-naive patients, who are adherent, take darunavir with food and are not using concomitant medication reducing darunavir concentrations, 800/100 mg of darunavir/ritonavir once daily is adequate in pregnancy. For all other patients 600/100 mg of darunavir/ritonavir twice daily is recommended during pregnancy.
Clinical Infectious Diseases | 2015
M.I. Blonk; Angela Colbers; Carmen Hidalgo-Tenorio; Kabamba Kabeya; Katharina Weizsäcker; Annette Haberl; José Moltó; David Hawkins; M.E. van der Ende; Andrea Gingelmaier; Graham Taylor; J. Ivanovic; Carlo Giaquinto; David M. Burger; A.J.A.M. van der Ven
BACKGROUND The use of raltegravir in human immunodeficiency virus (HIV)-infected pregnant women is important in the prevention of mother-to-child HIV transmission, especially in circumstances when a rapid decline of HIV RNA load is warranted or when preferred antiretroviral agents cannot be used. Physiological changes during pregnancy can reduce antiretroviral drug exposure. We studied the effect of pregnancy on the pharmacokinetics of raltegravir and its safety and efficacy in HIV-infected pregnant women. METHODS An open-label, multicenter, phase 4 study in HIV-infected pregnant women receiving raltegravir 400 mg twice daily was performed (Pharmacokinetics of Newly Developed Antiretroviral Agents in HIV-Infected Pregnant Women Network). Steady-state pharmacokinetic profiles were obtained in the third trimester and postpartum along with cord and maternal delivery concentrations. Safety and virologic efficacy were evaluated. RESULTS Twenty-two patients were included, of which 68% started raltegravir during pregnancy. Approaching delivery, 86% of the patients had an undetectable viral load (<50 copies/mL). None of the children were HIV-infected. Exposure to raltegravir was highly variable. Overall area under the plasma concentration-time curve (AUC) and plasma concentration at 12 hours after intake (C12h) plasma concentrations in the third trimester were on average 29% and 36% lower, respectively, compared with postpartum: Geometric mean ratios (90% confidence interval) were 0.71 (.53-.96) for AUC0-12h and 0.64 (.34-1.22) for C12h. The median ratio of raltegravir cord to maternal blood was 1.21 (interquartile range, 1.02-2.17; n = 9). CONCLUSIONS Raltegravir was well tolerated during pregnancy. The pharmacokinetics of raltegravir showed extensive variability. The observed mean decrease in exposure to raltegravir during third trimester compared to postpartum is not considered to be of clinical importance. Raltegravir can be used in standard dosages in HIV-infected pregnant women. CLINICAL TRIALS REGISTRATION NCT00825929.
Oncology Letters | 2017
Bernd Kost; Jörg Hofmann; Susanne Stoellnberger; Florian Bergauer; Thomas Blankenstein; Irene Alba‑Alejandre; Angela Stein; Claudia Stuckart; Katharina Weizsäcker; Ioannis Mylonas; Sven Mahner; Andrea Gingelmaier
Infection with certain types of human papillomavirus (HPV) has been associated with the development of cervical and anal cancer. Worldwide, the incidence of anal cancer has increased markedly. The present study aimed to evaluate the prevalence of HPV infection of the uterine cervix and anal canal in human immunodeficiency virus (HIV)- and non-HIV-infected risk populations. Cervical and anal HPV swabs and cytology samples were collected from 287 patients at the University Hospital of Munich, Germany between 2011 and 2013. Patients were divided into HIV-negative controls (G1) and two risk groups, including HIV-negative patients with cytological abnormalities of the cervix (G2) and HIV-infected patients (G3). Data, including clinical parameters, were analysed. The risk groups had significantly more positive results for HPV in the anus (71.03 and 83.15% for G2 and G3, respectively), as compared with G1. The predominant HPV genotypes found in the anus were high-risk HPV genotypes, which were significantly correlated with concomittant cervical HPV findings. In the risk groups, a significant association between the cytological findings and HPV detection in the cervix was found, while the results of the anus revealed no significance. The results of the present study suggested that the prevalence of HPV infection in the anal canal of risk populations is high. Furthermore, patients with abnormal cervical cytology results and HIV-infected women, irrespective of their individual cervical findings, may have a risk of concomittant anal high-risk HPV infection. Based on the predominant HPV genotypes found in the study, HPV vaccination could reduce the incidence of anal cancer. Nevertheless, high-risk patients should be intensively screened for anal squamous intraepithelial abnormalities to avoid invasive cancer stages.
Antiviral Therapy | 2014
Angela Colbers; David Hawkins; Carmen Hidalgo-Tenorio; M.E. van der Ende; Andrea Gingelmaier; Katharina Weizsäcker; Kabamba Kabeya; Graham Taylor; Jürgen K. Rockstroh; John S. Lambert; José Moltó; Christoph Wyen; S.T. Sadiq; J. Ivanovic; Carlo Giaquinto; David M. Burger
BACKGROUND We studied the effect of pregnancy on atazanavir pharmacokinetics in the presence and absence of tenofovir. METHODS This was a non-randomized, open-label, multicentre Phase IV study in HIV-infected pregnant women recruited from European HIV treatment centres. HIV-infected pregnant women treated with boosted atazanavir (300/100 mg or 400/100 mg atazanavir/ritonavir) as part of their combination antiretroviral therapy (cART) were included in the study. 24 h pharmacokinetic curves were recorded in the third trimester and postpartum. Collection of a cord blood and maternal sample at delivery was optional. RESULTS 31 patients were included in the analysis, 21/31 patients used tenofovir as part of cART. Median (range) gestational age at delivery was 39 weeks (36-42). Approaching delivery 81% (25 patients) had an HIV viral load <50 copies/ml, all <1,000 copies/ml. Least squares means ratios (90% CI) of atazanavir pharmacokinetic parameters third trimester/postpartum were: 0.66 (0.57, 0.75) for AUC0-24h, 0.70 (0.61, 0.80) for Cmax and 0.59 (0.48, 0.72) for C24h. No statistical difference in pharmacokinetic parameters was found between patients using tenofovir versus no tenofovir. None of the patients showed atazanavir concentrations <0.15 mg/l (target for treatment-naive patients). One baby had a congenital abnormality, which was not likely to be related to atazanavir/ritonavir use. None of the children were HIV-infected. CONCLUSIONS Despite 34% lower atazanavir exposure during pregnancy, atazanavir/ritonavir 300/100 mg once daily generates effective concentrations for protease inhibitor (PI)-naive patients, even if co-administered with tenofovir. For treatment-experienced patients (with relevant PI resistance mutations) therapeutic drug monitoring of atazanavir should be considered to adapt the atazanavir/ritonavir dose on an individual basis. ClinicalTrials.gov number NCT00825929.
Reproductive Toxicology | 2014
Ansgar Brüning; Tanja Kimmich; German J. Brem; Marie L. Buchholtz; Ioannis Mylonas; Bernd Kost; Katharina Weizsäcker; Andrea Gingelmaier
Combined antiretroviral therapy has proven efficacy in decreasing vertical HIV transmission. However, endoplasmic reticulum stress is a known side effect of HIV protease inhibitors. We investigated endoplasmic reticulum stress in placentas of HIV-infected and uninfected mothers by PCR-based splicing analysis of the specific endoplasmic reticulum stress marker XBP1 in post-delivery placental samples of uninfected mothers and in HIV-infected mothers taking antiretroviral therapy. No elevated XBP1 splicing could be detected in placentas of uninfected mothers and most of the mothers receiving combined anti-retroviral therapy. However, markedly elevated XBP1 splicing was found in the placentas of three individuals on combined antiviral therapy, all receiving lopinavir or atazanavir. In vitro experiments confirmed induction of endoplasmic reticulum stress by lopinavir and atazanavir in trophoblast-derived cell lines. Since endoplasmic reticulum stress occurred in selective patients only, individual differences in susceptibility of HIV-infected mothers to protease inhibitor induced endoplasmic reticulum stress can be postulated.
Zeitschrift Fur Geburtshilfe Und Neonatologie | 2012
A. Pohl-Schickinger; Cornelia Feiterna-Sperling; Katharina Weizsäcker; Christoph Bührer
Protocols recommended in the USA and Germany for the postnatal treatment of congenital toxoplasmosis are mainly based on the National Collaborative Chicago-based Congenital Toxoplasmosis Study that calls for daily administration of pyrimethamine in combination with sulfadiazine for several months, then 3 times a week. The recommended total duration of treatment is 12 months. This scheme necessitates frequent white blood cell counts that often result in the discontinuation of treatment because of severe neutropenia even with the concomitant administration of folinic acid. In contrast, the administration of pyrimethamine with sulfadoxine every 2 weeks for 2 years, as used by a referral centre in Toulouse, France, is associated with less toxicity. The efficacy may even be improved, as judged by the rate of new chorioretinal lesions. In the absence of larger randomised studies the Toulouse protocol appears to have several advantages when a decision has to be made to treat infants with congenital toxoplasmosis.
Medical Microbiology and Immunology | 2017
Vera Seidel; Cornelia Feiterna-Sperling; Jan-Peter Siedentopf; Jörg Hofmann; Wolfgang Henrich; Christoph Bührer; Katharina Weizsäcker
Congenital cytomegalovirus (CMV) infection is the leading cause for sensorineural hearing loss and mental retardation in children without genetic diseases worldwide. There is little evidence guiding therapeutic strategies during pregnancy when intrauterine fetal CMV infection is confirmed. We provide a systematic review of the use of ganciclovir (GCV) or VGCV during pregnancy discussing safety of its use for mother and fetus and describe two cases of intrauterine therapy of fetal CMV infection with valganciclovir (VGCV). A PubMed database search was done up to November 16, 2016 without any restrictions of publication date or journal, using the following keywords: “valganciclovir” or “ganciclovir” and “pregnan*”. Furthermore, citations were searched and expert references were obtained. Reported cases were considered if therapy was in humans and initiation of treatment of the CMV infection was during pregnancy. In total, seven case reports were retrieved which described GCV or VGCV use during pregnancy for fetal or maternal CMV infection. In the four cases of treatment for maternal CMV infection, no negative effects on the fetus were reported. Three cases of GCV administration to pregnant woman with the intention of fetal treatment after proven fetal infection were found. We additionally present two cases of VGCV treatment in pregnancy from our center of tertiary care. VGCV seems to be a safe treatment for congenital CMV infection for the mother and the fetus. Therapeutic concentrations can be achieved in the fetus by oral intake of the mother and CMV replication can be suppressed. Larger studies are needed to evaluate this therapeutic intervention and the long-term effects.
Infection | 2016
Vinzenz Boos; Cornelia Feiterna-Sperling; Akosua Sarpong; Lars Garten; Malte Cremer; Katharina Weizsäcker; Christoph Bührer; Christof Dame
We report on a late-preterm neonate with severe congenital cytomegalovirus (CMV) infection, refractory to antiviral therapy with ganciclovir. Subsequent immune diagnostics led to the finding of HIV infection at day 69, even though the mother tested negative for HIV in early pregnancy. Thus, in congenital CMV infection, HIV testing should be performed to elucidate maternal HIV seroconversion during late pregnancy. Our case strongly supports third trimester screening of HIV infection acquired during pregnancy, yet recommended only for women with traditional risk factors for HIV or living in an area of high HIV prevalence.