High-Resolution Ultrasound Including Contrast-Enhanced Ultrasound (CEUS) for the Detection of Gas Formation during Aspergillus Fumigatus Infection in Mice.

PURPOSE: A. fumigatus infections represent a major threat for patients with a suppressed immune system. Early diagnosis is of importance for a favorable outcome but appears to be difficult due to limited diagnostic procedures. Here we investigated the sensitivity of high-resolution ultrasound (HRU) for the detection of A. fumigatus infection in the liver. MATERIALS AND METHODS: BALB/c mice were intravenously infected with A. fumigatus and monitored by HRU, Doppler sonography (CCDS), contrast-enhanced ultrasound (CEUS), and real-time strain color-coded elastography (CCE) using a multi-frequency probe (6 - 15 MHz). Contrast media bolus injection of sulfur-hexafluoride micro-bubbles was applied and digital cine-loops from the arterial phase, as well as the portal venous phase up to the late phase of the whole liver were analyzed. All data were correlated to the histopathological findings. RESULTS: Using HRU and CEUS, a sonic shadow was detected in all infected animals. All Aspergillus-infected nodes from 3 - 6 mm in the liver showed a shadow with rim enhancement and no intranodal enhancement when using CEUS. A. fumigatus infection was confirmed by CFU assessment and histopathological analysis. Granulomas were not associated with shadowing on B-mode. In contrast, granulomas with a diameter above 5 mm and a higher stiffness in CCE generated particularly an arterial rim enhancement and portal venous washout without contrast media uptake in the late phase. In addition, CEUS was able to define dynamic capillary microvascularization of infected liver areas. CONCLUSION: Liver lesions associated with A. fumigatus infection can be detected in mice when combined with CEUS and CCE in vivo.

[A 55-year-old man with abdominal pain and fever]. / 55-jähriger Patient mit abdominellen Schmerzen und Fieber.

A 55-year-old man was admitted for evaluation of chronic abdominal pain and fever. Computed tomography demonstrated a retroperitoneal inflammatory process involving the mesenteric root. Adipose tissue biopsy showed panniculitis mesenterica with granulomas. Further examinations confirmed the diagnosis of plasmocytoma type IgG kappa. Treatment with steroids (prednisolone), resulted in immediate improvement of pain and fever. Mesenteric panniculitis represents a paraneoplastic syndrome associated with non-Hodgkin lymphoma.

Successful treatment of Scedosporium apiospermum soft tissue abscess with caspofungin and voriconazole in a severely immunocompromised patient with acute myeloid leukemia.

We report the case of a 53-year-old female patient with refractory acute myeloid leukemia developing a necrotic, soft tissue abscess on the right forearm caused by Scedosporium apiospermum during prolonged severe neutropenia (absolute white blood cell count <500/µL for 49 days). In the context of the severely immunocompromised state of the patient and her need for allogeneic hematopoietic stem cell transplantation (HSCT), surgical treatment options were not favored. Therefore, combined antifungal therapy with voriconazole and caspofungin was started, based on the results of the in vitro testing (minimum inhibitory concentrations of voriconazole, posaconazole, and amphotericin B: 1, 4, and >2mg/L, respectively). The local site of infection slowly improved clinically and no spread of S. apiospermum infection to other sites was observed. After HSCT, the soft tissue abscess resolved completely and the patient has remained free of S. apiospermum infection since then. We successfully demonstrate that the use of combined antifungal therapy with voriconazole and casopfungin may further improve the clinical course and provides a promising therapeutic option to treat Scedosporium infections in such patients.

Determination of the endothelin receptor antagonist ABT-627 and related substances by high performance liquid chromatography.

The determination of the endothelin (ET) antagonist receptor ABT-627 (I) and related substances is performed by HPLC. I is determined in bulk drug substance and drug formulation using isocratic conditions and an Inertsil ODS-2 column. The determination is stability indicating and detector response is linear from 24 to 118 microg ml(-1) (33-164% of assay level). Intermediate precision for the determination ranged from +/- 0.60 to +/- 1.9% RSD. The measurement is accurate, with quantitative recovery of I from the formulation placebo. Related substances in I and formulated I are determined using the same chromatographic conditions, with a gradient elution profile to elute impurities having varying relative polarities. The detector response for related substances determination is linear for I from 0.60 to 17.8 microg ml(-1) (0.05-1.5% of assay level) with the limit of detection and quantitation estimated at 0.01 and 0.05%, respectively. Comparable precision was obtained in drug substance and drug formulation (RSD values +/- 3.7 to +/- 12% and +/- 5.5 to 16.9%, respectively for impurities ranging from 0.05 to 0.30%). The quantitated impurities agreed well for the same lot of I when assayed as a bulk substance and after the formulation into a drug product.

High resolution ultrasound including elastography and contrast-enhanced ultrasound (CEUS) for early detection and characterization of liver lesions in the humanized tumor mouse model.

PURPOSE: In this study we investigated the sensitivity of high resolution ultrasound (HRU) in the detection of small liver tumors and its microcirculation in a humanized tumor mouse model (HTM). These mice develop a complete human immune system and human breast cancer growth in the liver which allows the investigation of antibody based immunotherapies under human like conditions. METHOD: HTM were generated by the co-transplantation of human breast cancer cells and human hematopoietic stem cells. HRU, Doppler sonography (CCDS), contrast enhanced ultrasound (CEUS) and color-coded elastography were performed on all HTM and confirmed by histopathological assessment. RESULTS: Using HRU and CEUS, noncystic solid liver lesions between 2 and 11 mm (mean 3.5 mm) size were detectable in HTM. Granulomatous areas were identified by B-scan imaging, showing areas of higher stiffness in elastography and areas without contrast media uptake in the late phase (CEUS). In addition, CEUS detected capillary microcirculation of benign and malignant liver lesions smaller than 10 mm. CONCLUSION: Beyond human breast cancer HTM additionally developed small parenchymal liver lesions, which could be characterized by HRU in combination with CEUS and elastography in-vivo. Nevertheless, the defined diagnoses of solid liver lesions less than 5 mm require confirmation by histopathology.

[Epithelial-mesenchymal transition of biliary epithelial cells in advanced liver fibrosis]. / Epitheliale-mesenchymale Transdifferenzierung von Gallengangsepithelzellen bei fortgeschrittener Leberfibrose.

UNLABELLED: The conversion of epithelial cells in a mesenchymal cell type is called "epithelial-mesenchymal-transition" (EMT). This process is defined by a loss of epithelial specific characteristics such as cell adhesion, polarity and a reorganization of cytoskeletal proteins. EMT has been shown to be involved in progression of cancer and in obstructive renal fibrosis. In this study we analyzed liver tissues in a bile-duct ligation model of rats and human liver biopsies with cholestatic fibrosis and chronic hepatitis c infection to determine if biliary epithelial cells undergo phenotypical and functional changes during chronic injury. METHODS: Liver tissue of rats and human patients was examined by immunohistochemistry using antibodies against epithelial and mesenchymal specific targets as well as molecules of potentially activated signaling pathways. To study contribution of biliary epithelial cells in extracellular matrix production we performed laser microdissection combined with real-time PCR. RESULTS: Bile duct ligation in rats induced a prominent biliary epithelial proliferation and a pronounced expression of vimentin was observed in biliary epithelial cells, whereas no vimentin expression was detectable in bile duct cells of sham operated rats. In human liver biopsies from patients with cholestatic fibrosis and chronic hepatitis c infection a prominent biliary expression of vimentin could be shown. Despite this, epithelial marker proteins were still detectable. Further, we observed collagen I mRNA expression in laser microdissected bile ducts. CONCLUSION: Biliary epithelial cells show cytoskeletal rearrangements during chronic liver injury towards a mesenchymal phenotype. The detection of collagen I mRNA in bile duct cells suggests that they might participate in extracellular matrix production.