Ureaplasma urealyticum and Mycoplasma hominis are common inhabitants of the human genital tract. Increasingly, serious and sometimes fatal infections in immunocompromised hosts have been reported, ...highlighting their pathogenic potential. We reviewed the clinical impact of positive Ureaplasma spp. and Mycoplasma spp. urine cultures in 10 renal allograft recipients who presented with sterile leukocyturia. Five recipients remained asymptomatic. Five patients were symptomatic with dysuria or pain at the graft site. Three patients developed biopsy‐proven acute graft pyelonephritis with graft dysfunction. One of these patients additionally showed a renal abscess as demonstrated by magnetic resonance imaging (MRI). All were successfully treated. A literature search revealed a substantial number of case reports with severe and sometimes fatal Ureaplasma spp. or Mycoplasma spp. infections in immunocompromised patients. Colonization rate is high in renal transplant patients. A subset of patients is at risk for invasive disease.
The vascular disrupting agent ombrabulin rapidly reduces tumor blood flow and causes necrosis in vivo. A phase I dose-escalation study was designed to determine the recommended phase II dose (RP2D) ...of single-agent ombrabulin administered once every three weeks in patients with advanced solid malignancies.
Ombrabulin (30-minute infusion) was escalated from 6 to 60 mg/m2, with RP2D cohort expansion. Safety, tumor response, pharmacokinetics, and pharmacodynamic biomarkers were evaluated.
Eleven dose levels were evaluated in 105 patients. Two patients had dose-limiting toxicities in cycle 1 during escalation: grade 3 abdominal pain at 50 mg/m2, grade 3 tumor pain/grade 3 hypertension at 60 mg/m2, and the RP2D was 50 mg/m2 (39 patients). Common toxicities were headache, asthenia, abdominal pain, nausea, diarrhea, transient hypertension, anemia, and lymphopenia. No clinically significant QTc prolongations or left ventricular ejection fraction (LVEF) decreases occurred. Ombrabulin was rapidly converted to its active metabolite RPR258063 (half-life 17 minutes and 8.7 hours, respectively), both having dose-proportional exposure. Weak inhibition of CYP2C19-mediated metabolism occurred at the clinical doses used and there was no effect on CYP1A2 and CYP3A4. A patient with rectal cancer had a partial response and eight patients had stable disease lasting four months or more. Circulating endothelial cells (CEC), VEGF, and matrix metalloproteinase (MMP)-9 levels increased significantly six to 10 hours postinfusion in a subset of patients.
The recommended schedule for single-agent ombrabulin is 50 mg/m2 every 3 weeks. CECs, VEGF, and MMP-9 are potential biomarkers of ombrabulin activity.
To prospectively assess the diagnostic accuracy of nonenhanced three-dimensional (3D) steady-state free precession (SSFP) magnetic resonance (MR) angiography for detection of renal artery stenosis ...(RAS), with breath-hold contrast material-enhanced MR angiography performed as the reference standard.
The study was local ethics committee approved; all patients gave written informed consent. Fifty-three patients (30 male, 23 female; mean age, 58 years) with arterial hypertension and suspected of having RAS were examined with 1.5-T 3D SSFP renal MR angiography. Stenosis grade, maximal visible vessel length, and subjective image quality were compared. Sensitivity, specificity, accuracy, and negative predictive value (NPV) were calculated on artery-by-artery and patient-by-patient bases. The significance of the results was assessed with the paired two-sided t test for continuous variables and with the marginal homogeneity test for categorical variables. Cohen kappa statistics were used to estimate interobserver agreement.
One hundred eight renal arteries with 20 significant (>or=50%) stenoses were detected with contrast-enhanced MR angiography. At artery-by-artery analysis, sensitivity, specificity, accuracy, and NPV of nonenhanced SSFP MR angiography for RAS detection were 100%, 93%, 94%, and 100%, respectively, for observer 1 and 95%, 95%, 95%, and 99%, respectively, for observer 2. Corresponding patient-by-patient values were 100%, 92%, 94%, and 100%, respectively, for observer 1 and 100%, 95%, 96%, and 100%, respectively, for observer 2. Overestimation of stenosis grade with SSFP MR angiography resulted in six and four false-positive findings for readers 1 and 2, respectively. Mean maximal visible lengths of the renal arteries were 69.9 mm at contrast-enhanced MR angiography and 61.1 mm at SSFP MR angiography (P<.001). Both techniques yielded good to excellent image quality.
Slab-selective inversion-prepared 3D SSFP MR angiography had high sensitivity, specificity, accuracy, and NPV for RAS detection, without the need for contrast material. However, RAS severity was overestimated in some patients.
Aims and Background
Bone metastasis below the knee from primary lung cancer is rare. Discussion of such cases in a multidisciplinary team is important to establish the correct treatment approach.
...Case report
We analyzed the diagnostic pathway of a 53-year-old female patient with a 5-month history of pain in the right foot. The patient underwent several radiological examinations for the pain. An initial diagnosis of osteoporotic syndrome was made, followed by a diagnosis of primary sarcoma. Only when the patient continued to have pain were other radiological examinations performed and a biopsy of the right ankle taken. This revealed a metastasis from undifferentiated pulmonary adenocarcinoma. A total-body computed tomography scan did not show any tumor locations apart from the primary lung cancer. The patient underwent chemotherapy and palliative therapies. This case has been reported for its rarity.
Tularemia is a zoonosis caused by the infection of
(a gram-negative aerobic bacterium). Transmission to other animals or humans usually occurs through insect or tick bites, direct contact with a ...contaminated environment (mud or water), infected animals - mainly lagomorphs - or by ingesting undercooked meat or inhaling contaminated dust (hay or soil). This paper discusses the case of a 32-year-old man, who came to our Emergency Room presenting with persistent fever, inguinal lymphadenopathy, and an ulcer on his left lower limb on a linear morphoea lesion that had been there for some time. The lesion was surrounded by erysipelas. After hospitalization and tests, the patient was diagnosed with ulceroglandular tularemia. Antibiotic treatment with doxycycline resolved the clinical picture, but not the morphoea lesion.
The aim of this work was to evaluate detection of low-contrast objects and image quality in computed tomography (CT) phantom images acquired at different tube loadings (i.e. mAs) and reconstructed ...with different algorithms, in order to find appropriate settings to reduce the dose to the patient without any image detriment.
Images of supraslice low-contrast objects of a CT phantom were acquired using different mAs values. Images were reconstructed using filtered back projection (FBP), hybrid and iterative model-based methods. Image quality parameters were evaluated in terms of modulation transfer function; noise, and uniformity using two software resources. For the definition of low-contrast detectability, studies based on both human (i.e. four alternative forced-choice test) and model observers were performed across the various images.
Compared to FBP, image quality parameters were improved by using iterative reconstruction (IR) algorithms. In particular, IR model-based methods provided a 60% noise reduction and a 70% dose reduction, preserving image quality and low-contrast detectability for human radiological evaluation. According to the model observer, the diameters of the minimum detectable detail were around 2 mm (up to 100 mAs). Below 100 mAs, the model observer was unable to provide a result.
IR methods improve CT protocol quality, providing a potential dose reduction while maintaining a good image detectability. Model observer can in principle be useful to assist human performance in CT low contrast detection tasks and in dose optimization.
Background
The aim of this work was to evaluate detection of low-contrast objects and image quality in computed tomography (CT) phantom images acquired at different tube loadings (i.e. mAs) and ...reconstructed with different algorithms, in order to find appropriate settings to reduce the dose to the patient without any image detriment.
Methods
Images of supraslice low-contrast objects of a CT phantom were acquired using different mAs values. Images were reconstructed using filtered back projection (FBP), hybrid and iterative model-based methods. Image quality parameters were evaluated in terms of modulation transfer function; noise, and uniformity using two software resources. For the definition of low-contrast detectability, studies based on both human (i.e. four-alternative forced-choice test) and model observers were performed across the various images.
Results
Compared to FBP, image quality parameters were improved by using iterative reconstruction (IR) algorithms. In particular, IR model-based methods provided a 60% noise reduction and a 70% dose reduction, preserving image quality and low-contrast detectability for human radiological evaluation. According to the model observer, the diameters of the minimum detectable detail were around 2 mm (up to 100 mAs). Below 100 mAs, the model observer was unable to provide a result.
Conclusion
IR methods improve CT protocol quality, providing a potential dose reduction while maintaining a good image detectability. Model observer can in principle be useful to assist human performance in CT low-contrast detection tasks and in dose optimisation.
To compare the diagnostic accuracy of gadobenate dimeglumine (Gd-BOPTA)-enhanced versus gadoterate meglumine (Gd-DOTA)-enhanced magnetic resonance (MR) angiography in patients with peripheral ...arterial occlusive disease (PAOD).
Fifty-six patients underwent MR angiography enhanced with either Gd-DOTA (28 patients) or Gd-BOPTA (28 patients). All arterial segments from the renal arteries to the distal run-off vessels were evaluated for disease severity. The sensitivity, specificity, and accuracy of MR angiography enhanced with both agents separately were evaluated with a paired t test; digital subtraction angiography was the reference standard. Interobserver variability was assessed by using the Cohen test.
Diagnostic MR angiograms were obtained in all 56 patients. Overall, sensitivity and specificity of Gd-DOTA-enhanced MR angiography were 96% and 93%, respectively, for observer 1 and 96% and 85%, respectively, for observer 2 (kappa = 0.82). Corresponding values for Gd-BOPTA-enhanced MR angiography were 94% and 93%, respectively, for observer 1 and 94% and 89%, respectively, for observer 2 (kappa = 0.78). No consistent differences between the two contrast materials in assessment of PAOD in the renal to popliteal arteries were observed. For assessment below the knee, specificity was slightly higher in the Gd-BOPTA group-91% and 84% for observers 1 and 2, respectively-than in the Gd-DOTA group-89% and 77%, respectively (P <.01). The number of nonassessable below-the-knee segments was significantly lower in the Gd-BOPTA group: nine of 299 segments versus 25 of 312 segments in the Gd-DOTA group (P <.01).
At MR angiography of the distal run-off vessels, Gd-BOPTA yielded higher specificity and a significantly smaller number of nonassessable segments than Gd-DOTA. The diagnostic accuracy of the two gadolinium chelates at peripheral MR angiography was comparable in the renal to popliteal arteries.
To test the clinical value of magnetic resonance imaging (MRI) pelvimetry for the diagnosis of cephalopelvic disproportion.
All deliveries from January 1993 through December 1994 were reviewed to ...identify 42 nulliparas at term with vertex presentation and cesarean delivery due to dystocia. Complete data were available for 41 women, and subjects were divided into the following two subgroups, according to clinical data: “cephalopelvic disproportion” (n = 28) and “failure to progress” (n = 13). Ten nulliparous women with uncomplicated vaginal delivery served as controls. Pelvimetry data from postpartum MRI were correlated with fetal and neonatal dimensions to evaluate various criteria for the diagnosis of cephalopelvic disproportion.
Comparing both the fetal head volume derived from antepartum ultrasound assessment and the neonatal head volume (postpartum measurement) with maternal pelvic capacity determined by MRI, cephalopelvic disproportion (head volume exceeding pelvic capacity) indicated that 25 and 27, respectively, of the 28 women had been clinically diagnosed correctly with cephalopelvic disproportion, corresponding to sensitivities of 89% and 96%, respectively. Fetal head volume was not larger than pelvic capacity in any of the women in the control group. In seven of the 13 women diagnosed as “failure to progress,” the fetal head volume exceeded the pelvic capacity.
A fetal head volume estimate exceeding MRI-measured pelvic capacity is a frequent rinding in nulliparas with cesarean birth due to cephalopelvic disproportion. An appropriate prospective study to determine the benefits of an antepartum diagnosis of cephalopelvic disproportion in high-risk nulliparas is warranted.
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