Gunnar Blumenstock

University of Tuebingen, Tübingen, Baden-Württemberg, Germany

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Publications (98)188.17 Total impact

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    ABSTRACT: The distinction between constitutional delay of growth and puberty (CDGP) and isolated hypogonadotropic hypogonadism (IHH) in males with delayed puberty is difficult but important for timely treatment. We assessed the accuracy of the GnRH agonist test (triptorelin 0.1 mg) in comparison with inhibin B alone or in combination with basal LH for the diagnosis of IHH.
    Clinical Endocrinology 09/2014; · 3.40 Impact Factor
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    ABSTRACT: Previous studies have shown a benefit of magnetic resonance (MR)-diffusion-weighted imaging (DWI) for follow-up after liver radiofrequency (RF) ablation. However, no data are available concerning acute changes of DWI characteristics immediately after RF ablation.
    Acta radiologica (Stockholm, Sweden : 1987). 09/2014;
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    ABSTRACT: To assess the long-term efficacy and tolerability of both derivatives of mycophenolic acid, mycophenolate mofetil (MMF) and mycophenolate sodium (MPS), in the therapy of patients with birdshot chorioretinopathy (BSCR).
    The British journal of ophthalmology. 07/2014;
  • International Orthopaedics 06/2014; · 2.32 Impact Factor
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    ABSTRACT: The purpose of this study was to assess the use of continuous epidural analgesia in pediatric patients undergoing major abdominal tumor surgery. Children undergoing major abdominal tumor surgery at our institution between 2008 and 2012 (n=40) received continuous epidural analgesia via an epidural catheter. Surgical trauma scores, pain scores, and clinical data of the children were compared to a pair-matched historical control group operated on between 2002 and 2007 without epidural analgesia. Pain levels in the study group on day 1 and 3 after surgery were lower compared to the control group. The differences did, however, not reach statistical significance (p=0.15 and 0.09). Children in the study group received significantly fewer additional doses of piritramide or morphine (45% versus 82%, p<0.001). Despite significantly higher surgical trauma scores in the study group (p=0.018), there were no statistical differences regarding clinical parameters, such as mechanical ventilation time, time on intensive care unit, and total hospital stay. There were no catheter-related complications. Continuous epidural analgesia is beneficial for children undergoing complex abdominal tumor surgery with regard to pain levels, postoperative recovery, and general clinical course. Expertise of the managing team, a careful patient selection, and a continuous quality assessment are essential for success.
    Journal of Pediatric Surgery 04/2014; 49(4):551-5. · 1.38 Impact Factor
  • A Tepass, K Weise, B Rolauffs, G Blumenstock, C Bahrs
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    ABSTRACT: Various treatment options exist for displaced proximal humeral fractures. The impact of the level of hospital care and frequency of treatment on current treatment regimens in Germany was analyzed. A total of 576 hospitals were included. The survey covered questions on frequency, diagnostics, classification, therapy, complications, and clinical scenarios. In all, 48% of the hospitals returned the questionnaire: 73% treat more than 60% of the fractures surgically, mainly with angle-stable implants. The angle-stable plate is the treatment of choice for young patients, but older patients are treated using other treatment options. Problems and complications included malreduction, secondary displacement, screw perforation, avascular necrosis, and impingement. According to treatment indication, implant choice, and common complications, no significant differences between the level of hospital care and frequency of treatment were observed. Independent of the level of hospital care and frequency of treatment, there is a trend for head-preserving angular-stable surgery with a homogenous level of treatment in Germany.
    Der Unfallchirurg 03/2014; · 0.64 Impact Factor
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    ABSTRACT: The aim of the study was to assess the long-term efficacy and tolerability of tumour necrosis factor α (TNFα) inhibitors in the therapy of children with refractory antinuclear antibody (ANA)-associated chronic anterior uveitis. Retrospective analysis of 31 children with ANA-associated uveitis, treated with TNFα inhibitors with a follow-up period of at least 2 years. The outcome measures included: control of inflammation, corticosteroid-sparing potential and side effects. Twenty-three children (74%) were treated with adalimumab, five children (16%) with infliximab and three children (10%) with etanercept. Control of uveitis, defined as 0 anterior chamber cells while on ≤2 drops/day topical corticosteroids, was achieved in 22 of 31 patients (71%) after 1 year (95% CI 52% to 86%), and in 21 of 29 patients (72%) after 2 years of treatment (95% CI 53% to 87%). Control of uveitis was observed in 18 of 23 children (78%) treated with adalimumab, and in two of five children (40%) treated with infliximab. In all children treated with etanercept, no sufficient inflammatory control was found. Systemic corticosteroids could be discontinued in 71% (12/17 children) and topical corticosteroids in 55% (17/31) of the patients. Treatment-related side effects were found in nine children (29%, rate: 0.10/patient-year). Our data show that adalimumab and infliximab have beneficial effects in the therapy of severe ANA-associated anterior uveitis in children.
    The British journal of ophthalmology 01/2014; · 2.92 Impact Factor
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    ABSTRACT: Abstract Background: Intraocular inflammation of the posterior segment may be associated with neoplastic, infectious, and inflammatory diseases. Biopsy of vitreous and additional ocular tissue might be required for a definitive diagnosis. We therefore aimed to investigate the safety and usefulness of diagnostic vitrectomy in intraocular inflammation. Method: We performed an observational retrospective study of patients who underwent vitreous biopsy due to atypical intraocular inflammation, experienced failed resolution to empirical therapy, or for whom there was suspicion of an underlying neoplastic process. Results: Seventy consecutive patients were included due to idiopathic uveitis of the posterior segment unresponsive to systemic corticosteroids (n = 33, 47%), suspected vitreoretinal or choroidal lymphoma (n = 18, 26%), viral retinitis (n = 17, 24%), and suspected endogenous endophthalmitis (n = 2, 3%). Suspected viral retinitis was most often confirmed (13/17, 76%), followed by lymphoma (6/18, 33%). Remarkably, a proportion of suspected idiopathic uveitis was infectious (7/33, 21%). The most prevalent adverse event following diagnostic vitrectomy was cataract surgery in phakic patients (n = 16/41, 39% of phakic patients). Retinal detachments were observed chiefly in infectious or neoplastic disease (n = 5, 7%) after a median time of 105 days. Conclusion: Diagnostic vitrectomy was helpful in substantiating the clinical suspected diagnosis of posterior segment inflammation. Potential secondary adverse events should be kept in mind.
    Ocular immunology and inflammation 01/2014; · 0.72 Impact Factor
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    ABSTRACT: Aim of the study was to compare the short-term effects of oxygen therapy via a high-flow nasal cannula (HFNC) on functional and subjective respiratory parameters in patients with acute hypoxic respiratory failure in comparison to non-invasive ventilation (NIV) and standard treatment via a Venturi mask.
    BMC Anesthesiology 01/2014; 14:66. · 1.19 Impact Factor
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    ABSTRACT: Objective: While in adults not total body- or visceral fat mass, but liver fat content was found to independently determine insulin resistance, it is unclear whether these relationships are already present in obese adolescents. Design and Methods: 39 overweight/ obese adolescents were matched for sex and BMI with 39 adults. To compare the age- and sex-specific BMI values of adolescents and adults, the percentile value of each adolescent was projected to the age of 18. Body fat depots were quantified by whole-body magnetic resonance (MR) imaging. Liver fat content was measured with (1) H-MR spectroscopy. Insulin resistance was estimated from the homeostasis model assessment of insulin resistance (HOMA-IR). Results: Compared to overweight and obese adults, adolescents had higher HOMA-IR (p<0.001) and lower lean body mass (p=0.002). Furthermore, they had higher total body- (p=0.02), but lower visceral- (p<0.001) fat mass, while liver fat content was not significantly different between the groups (p=0.16). In both groups liver fat content (both p≤0.007), but not total body- or visceral fat mass (all p≥0.64) was an independent predictor of insulin resistance. Conclusions: Having lower visceral fat mass, overweight and obese adolescents are more insulin resistant than sex- and BMI-matched adults. Liver fat content, but not total body- or visceral fat mass, is an independent determinant of insulin resistance in adolescents.
    Obesity 12/2013; · 3.92 Impact Factor
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    ABSTRACT: Aims: To compare adult heights of GH-treated and GH-untreated patients with Silver-Russell syndrome (SRS) who were epigenotyped. Methods: This was a nonrandomized retrospective study with matched controls at a single center. Molecular analysis of 32 out of 37 GH-treated patients (16 females) revealed IGF2-H19 epimutations in 12 and maternal uniparental disomy of chromosome 7 (matUPD7) in 5 patients; 15 were negative. At start of GH, mean age was 7.2 years and mean height -3.34 standard deviation score (SDS). Mean GH dose used was 51 µg/kg·day, mean duration of therapy was 5.6 years. Puberty was blocked by GnRH analogs in 16 patients. The untreated group comprised 13 individuals (5 females, mean age 6.8 years and mean height -3.34 SDS). End points were adult height and overall height gain. Results: GH-treated patients reached an adult height of -2.12 ± 0.98 SDS gaining 1.22 SDS in comparison to baseline. Adult height SDS of the untreated was -3.13 ± 1.37 SDS. The matched treated patients were significantly taller than their untreated counterparts. Outcome was dependent on height at start of GH and duration of therapy. Height gain was highest in the shortest patients. Conclusions: GH improved adult height in SRS to a comparable degree as reported in nonsyndromic SGA children. A trend toward a better outcome in matUPD7 needs confirmation in larger cohorts.
    Hormone Research in Paediatrics 09/2013; · 1.55 Impact Factor
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    ABSTRACT: To analyze the clinical course, treatment, complications, outcome, and quality of life (QOL) in patients with perineal/perianal rhabdomyosarcoma (PRMS) treated within the CWS-86, -91, -96, and -2002P trials. Although multiple international study trials exist for the treatment of rhabdomyosarcoma, only very limited information is given on treatment, outcome, and QOL in PRMS. A total of 35 patients suffering from PRMS were treated with neoadjuvant chemotherapy. Local therapy with radiation and/or surgery was performed, followed by adjuvant chemotherapy. Functional long-term follow-up was evaluated by a gastrointestinal/QOL survey. Thirty-two patients were evaluated (exclusion n = 3). Eight patients had embryonal histology, and 24 patients had alveolar histology. The median age was 108 months (median follow-up: 5.8 years). The 5-year overall survival was 47% (95% confidence interval: 29-64). Sixteen IRS (Intergroup Rhabdomyosarcoma Study) III and IV patients had locoregional lymph node involvement at diagnosis. Seven patients were treated with chemotherapy/surgery alone [5-year event-free survival (EFS): 85.7%]. Eleven patients received only radiochemotherapy (5-year EFS: 27.3%). Combined radiochemotherapy/surgery was used in 12 patients (5-year EFS: 63.6%). Two patients were treated only with chemotherapy and they died. Patients with embryonal histology had a significantly better 5-year EFS (87.5%) than patients with alveolar histology (39.1%; P = 0.013). Some patients reported symptoms of fecal incontinence. The median Wexner fecal incontinence score was 9 (possible range: 0-20), and the median QOL score was 90.5 (applicable range: 0-144). The outcome of these patients remains unsatisfactory. Prognostic factors for a favorable outcome are tumor size of smaller than 5 cm, negative locoregional lymph nodes, age less than 10 years, low IRS group, and embryonal histology. Fecal incontinence seems to be a problem.
    Annals of surgery 09/2013; · 7.90 Impact Factor
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    ABSTRACT: Background: The impact of the European Working Time Directive and subsequent collective wage agreements for doctors from 2006 onwards were substantial. So far, no systematic evaluation of their application in Germany has been performed. We evaluated the impact four years after implementation of new shift models in a University Hospital for Gynaecology and Obstetrics (UHGO). Methods: A new shift model was created together with doctors of Tübingen UHOG in 2007 and implemented in 2008. Documentation of working hours has hence been done electronically. Adherence to the average weekly working time limit (AWTL) and the maximum of 10 h daily working time (10 h-dwt) was evaluated, as well as staffing costs in relation to case-weight points gathered within the German DRG (diagnosis related groups) System. Results: Staff increased from a mean of 44.7 full time equivalent (FTE) doctors in 2007 to 52.5 FTE in 2009, 50.8 in 2010, and 54.5 in 2011. There was no statistically significant difference of the monthly staff expenditures per case-weight between the years 2009 or 2010 vs. 2007. 2011, however, was significantly more expensive than 2007 (p = 0.02). The internal control group (five other departments of the university hospital) did not show an increase during the same period. AWTL were respected by 90, 96, and 98 % in 2009, 2010, and 2011, respectively. Of all shifts 10 h-dwt was exceeded by 7.4 % in 2009, 1.3 % in 2010, and 2.6 % in 2011, with significant differences between 2009 and both, 2010 and 2011 (p < 0.001), and between 2010 and 2011 (p = 0.02). Discussion: AWTL and 10 h-dwt could be continuously respected quite well after implementation of the new shift model without increasing the cost/earnings ratio for the first two years. However, in 2011 the ratio increased significantly (p = 0.02).
    Geburtshilfe und Frauenheilkunde 07/2013; 73(7):713-719. · 0.85 Impact Factor
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    ABSTRACT: Purpose: Amblyopia is one of the most common visual disorders in children. The risk of severe visual impairment on the healthy eye is doubled in patients with amblyopia. If detected early enough, the chances of visual rehabilitation are good. Treatment consists of refractive correction and occlusion of the dominant eye. Patient compliance is an important factor and can be monitored using thermosensors. It was the goal of our study to give proof of the principle that the wearing times of glasses and patches can be measured using a comparatively small and commercially available microsensor. Methods: Agreement between wearing times protocols of ocular patching/refractive correction and temperature measurements of thermosensors attached to the patches or glasses of three individuals were analysed using the Bland-Altman method. It was also analysed whether blinded persons could distinguish between temperature curves of patches and glasses, or temperature curves of an incubator or while worn in a pocket. Results: The temperatures picked up by the microsensors indicate the beginning and the end wearing times of either glasses or ocular patches through steep temperature difference and a distinct temperature curve during measurements. Although blinded test persons were able to cleary distinguish between temperature profiles from incubator/pocket measurements compared to glasses/patching, glasses and patching curves could be discriminated correctly in only 50%. Differences between wearing time protocols and temperature measurements were within the limits of agreement as stated by the Bland-Altman plots. Conclusion: The TheraMon(®) microsensor can reliably measure wearing times of glasses and ocular patches without making the wearer uncomfortable, although the data are not unquestionable, especially in higher surrounding temperatures. Further studies on a larger number of individuals with different wearing profiles are needed.
    Acta ophthalmologica 06/2013; · 2.44 Impact Factor
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    ABSTRACT: BACKGROUND & AIMS: Short bowel syndrome (SBS) and intestinal failure (IF) are multi-factorial conditions which in adults result from extensive intestinal resection. NOD2 is an intracellular pattern recognition receptor associated with CD. An unexpected high frequency of NOD2 mutations has been found in patients undergoing intestinal transplantation (35%). The role of NOD2 in a cohort with SBS/IF not specifically requiring intestinal transplantation has not been studied yet. METHODS: The course of 85 patients with non-malignant SBS/IF was characterized. The major NOD2 mutations, as well as ATG16L1 and IL23R were determined. The allele frequencies were compared to the published frequencies of CD patients and controls. RESULTS: In non-CD patients (72%) allele frequencies of NOD2 mutations were statistically more frequent than in controls (14% vs 6%, p = 0.006). In CD patients (28%) allele frequencies were not different between SBS and controls (29% vs 22%, p = 0.23). NOD2 mutations were neither associated with parameters potentially heralding the need for transplantation nor with an earlier time to the indication for intestinal transplantation. CONCLUSIONS: NOD2 mutations are associated with the development of SBS/IF in the absence of CD, but not with specific complications. NOD2 mutations may increase the risk for more extensive intestinal resection or may impair intestinal adaptation.
    Clinical nutrition (Edinburgh, Scotland) 03/2013; · 3.27 Impact Factor
  • European Urology Supplements 03/2013; 189(4):E916-E916. · 3.37 Impact Factor
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    ABSTRACT: Purpose:To compare volume, sphericity, and short-axis diameter of the coagulation zone of four commercially available microwave ablation systems with three technical concepts in an ex vivo setting and to formulate mathematical models to predict these quantities.Materials and Methods:Two high-power systems (systems A and B), a system that enables simultaneous use of three antennas (system C), and a non-perfusion-cooled system that automatically adapts power and frequency (system D) were tested in ex vivo bovine livers (108 ablations). Coagulation volume, sphericity, and mean short-axis diameter were assessed, and mathematical functions were fitted for each system and assessed with the coefficient of determination (R(2)). Analysis of variance and Tukey post hoc tests were used for interdevice comparison after 5 and 10 minutes and after maximum recommended ablation time.Results:Volume and short-axis diameter were determined by using a mathematical model for every system, with coefficients of determination of 0.75-0.98 and 0.70-0.97, respectively. Correlation for determination of sphericity was lower (R(2) = 0.01-0.68). Mean results with ablation performed according to manufacturer recommendations were as follows: Volume, sphericity, and short-axis diameter were 57.5 cm(3), 0.75, and 43.4 mm, respectively, for system A; 72.3 cm(3), 0.68, and 45.5 mm, respectively, for system B; 17.1 cm(3), 0.58, and 26.8 mm, respectively, for system C (one antenna); 76.5 cm(3), 0.89, and 50.6 mm, respectively, for system C (three antennas); and 56.0 cm(3), 0.64, and 40.9 mm, respectively, for system D. Systems A (mean volume, 52.4 cm(3) ± 4.5 [standard deviation]) and B (39.4 cm(3) ± 1.7) reach large ablation zones with 5-minute ablation.Conclusion:The largest ablation zone is obtained with systems B and C (three antennas) under maximum recommended ablation duration and with system A under short ablation time. The most spherical zone is obtained with system C (three antennas).© RSNA, 2013.
    Radiology 02/2013; · 6.34 Impact Factor
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    ABSTRACT: BACKGROUND: Studies that investigated possible associations between the complexity of proximal humeral fractures and patient characteristics are rare. We hypothesized that the grade of fracture complexity may correlate with age and gender of hospitalized, adult patients. METHODS: Based on the Neer classification, we defined four radiological grades of fracture complexity. The data of adult patients that were treated during a 9-year period at a German hospital serving a town of 80,000 inhabitants was reviewed. RESULTS: Seven hundred and eighty fractures were evaluated [518 female/262 male (66.41/33.59 %), average age 64.2 years (range 17.4-99.2)]. During the study period, the number of fractures increased to 167 %. Almost two-thirds of the patients were females and older than 60 years. Of all fractures, 86 % were displaced fractures. In patients younger than 60 years, 1.99-fold more complex fractures occurred in males (32.4 %) than in females (16.2 %). In contrast, in patients older than 60 years, 1.72-fold more complex fractures occurred in females (54.1 %) than in males (31.5 %). There was a significant association between low-energy trauma and female gender older than 60 years. CONCLUSIONS: Our study demonstrated an overall increase of displaced proximal fractures. The vast majority of patients with more complex fractures consisted of female patients older than 60 years.
    Journal of Orthopaedic Science 02/2013; · 0.96 Impact Factor
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    ABSTRACT: WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: There is increasing evidence that the receptor activator of nuclear factor κB ligand (RANKL) pathway not only contributes to the development of bone metastases, but also influences tumour biology in earlier stages of cancer. The study shows that preoperative serum levels of RANKL and its inhibitor osteoprotegerin (OPG) have a prognostic impact in patients undergoing radical prostatectomy for clinically localized prostate cancer. Both high levels of RANKL and a higher RANKL/OPG ratio are independent predictors of early biochemical recurrence in these patients. OBJECTIVE: To assess the prognostic impact of proteins of the receptor activator of nuclear factor κB (RANKL) pathway in serum samples from patients undergoing radical prostatectomy. PATIENTS AND METHODS: We retrospectively determined soluble RANKL (sRANKL) and osteoprotegerin (OPG) by ELISA in serum samples of 178 patients undergoing radical prostatectomy between 2004 and 2006. Clinical and patient follow-up data were analysed using the Wilcoxon-Mann-Whitney test, the Kaplan-Maier method, and single variable or multifactorial Cox proportional hazards analysis. RESULTS: Higher serum sRANKL levels (P = 0.01), lower serum OPG levels (P = 0.01) and a higher sRANKL/OPG ratio (P = 0.004) were significant risk factors for biochemical recurrence (BCR). In multifactorial analysis, adjusted for the common risk factors for BCR, sRANKL and sRANKL/OPG ratio were confirmed as independent prognostic factors. Neither sRANKL nor OPG showed a clear association with histopathological factors such as pT stage, pN Gleason score or resection margin status, nor were they associated with prostate-specific antigen level. CONCLUSIONS: Greater activity of the RANKL pathway in the serum of patients with prostate cancer undergoing radical prostatectomy is a risk factor for BCR. The RANKL pathway seems to contribute to the biological behaviour of prostate cancer even at the organ-confined stage of the disease.
    BJU International 01/2013; · 3.05 Impact Factor
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    ABSTRACT: Purpose: Comparison of dose area products (DAP) in diagnostic angiography procedures between an image intensifier (II) and a flat panel detector (FPD) angiography system and the evaluation of DAP/body mass index (BMI) dependency. Materials and Methods: An image intensifier system or a flat panel detector system was used to perform 571 diagnostic angiographies (n = 328 and n = 243, respectively) of 5 different types: peripheral arterial, venous, single leg, abdominal and upper extremity. The results were retrospectively analyzed. The DAP, fluoroscopy time (t) and the number of series of the respective interventions as calculated by the respective machines was compared for all interventions and for the respective subtypes and machines. The BMI dependency was calculated separately for both machines for all interventions by subdividing the patients into 6 BMI classes defined by the WHO. Results: The average DAP for all diagnostic interventions was 1958.9 cGy×cm2 (t = 384.6 s, n = 7.85 series) for the II and 2927.4 cGy×cm2 (t = 267.4 s, n = 7.02 series) for the FPD. Group-dependent differences ranged between + 21 and + 252 % when using the FPD system. After time standardization, the respective increases were found to be 120 % for the FPD system. The DAPs increased considerably in patients with higher BMIs (766.7 cGy × cm2 - 6892.6 cGy × cm2, II machine, 950.5 cGy × cm2 - 12 487.7 cGy × cm2, FPD machine) with a greater DAP gain seen for the FPD. The average duration of the interventions was higher using the II machine. Conclusion: The use of an FPD system led to higher DAP values compared to the II system in diagnostic angiographic procedures. In addition, increased BMI values led to higher DAPs, especially for the FPD machine. However, the average fluoroscopy times were shorter.
    RöFo - Fortschritte auf dem Gebiet der R 11/2012; · 2.76 Impact Factor

Publication Stats

443 Citations
188.17 Total Impact Points


  • 1999–2014
    • University of Tuebingen
      • • Institute for Clinical Epidemiology and Applied Biometry
      • • Department of Internal Medicine
      Tübingen, Baden-Württemberg, Germany
  • 2011
    • Universitätsklinikum Tübingen
      Tübingen, Baden-Württemberg, Germany
  • 2006–2007
    • Universität Heidelberg
      Heidelburg, Baden-Württemberg, Germany
    • Kassenärztliche Bundesvereinigung
      Berlín, Berlin, Germany
  • 2002–2003
    • Ludwig-Maximilian-University of Munich
      • Max-von-Pettenkofer Institute for Hygiene and Medical Microbiology
      München, Bavaria, Germany