Percutaneous ureteral biopsy: safety and diagnostic yield

Abdominal Radiology - To evaluate safety and diagnostic yield of percutaneous CT-guided biopsy of extrarenal upper urinary tract lesions. Retrospective review of our institutional database of...     

Incidence of major hemorrhage after aggressive image-guided liver mass biopsy in the era of individualized medicine

Purpose

To analyze a large volume of image-guided liver mass biopsies to assess for an increased incidence of major hemorrhage after aggressive liver mass sampling, and to determine if coaxial technique reduces major hemorrhage rate.

Methods

Patients who underwent image-guided liver mass biopsy over a 15-year period (December 7, 2001–September 22, 2016) were retrospectively identified. An aggressive biopsy was defined as a biopsy event in which ≥ 4 core needle passes were performed. Association of major hemorrhage after aggressive liver mass biopsy and other potential risk factors of interest were assessed using logistic regression analysis. For the subset of aggressive biopsies, Fisher’s exact test was used to compare the incidence of major hemorrhage using coaxial versus noncoaxial techniques.

Results

Aggressive biopsies constituted 11.6% of biopsy events (N =579/5011). The incidence of major hemorrhage with <4 passes was 0.4% (N =18/4432) and with ≥4 passes 1.2% (N =6/579). In univariable models, aggressive biopsy was significantly associated with major hemorrhage (OR 3.0, 95% CI 1.16–6.92, p =0.025). After adjusting for gender and platelet count, the association was not significant at the p =0.05 level (OR 2.58, 95% CI 0.927–6.24, p =0.067). The rate of major hemorrhage in the coaxial biopsy technique group was 1.4% (N =3/209) compared to 1.1% (N =4/370) in the noncoaxial biopsy technique group, which was not a significant difference (p =0.707).

Conclusions

Although aggressive image-guided liver mass biopsies had an increased incidence of major hemorrhage, the overall risk of bleeding remained low. The benefit of such biopsies will almost certainly outweigh the risk in most patients.

     

In vivo release and turnover of secreted platelet antiheparin proteins in rhesus monkey (Macaca mulatta)

Human and rhesus monkey platelets secrete at least two antiheparin proteins: platelet factor 4 (PF4) and low affinity platelet factor 4 (LA-PF4). Neither of these proteins showed species-related antigenic differences. As determined by radioimmunoassay, the levels of PF4 and LA-PF4 antigen per 10(9) monkey platelets amounted to 10.7 and 20.3 microgram, respectively. One milliliter of monkey plasma prepared from blood collected into an anticoagulant composed of EDTA, prostaglandin E1, and theophylline solution contained 22.4 ng LA-PF4 and 8.0 ng PF4. Concentrations of these two platelet-specific proteins in monkeys closely resembled levels found in human platelets and plasma. Infusion of prostacyclin (PGI2) (100 or 300 ng/kg/min) into monkeys for 15 min resulted in a significant decrease of plasma levels of LA-PF4 antigen and of PF4 by 40%--60% (p < 0.0001). This decrease was related to the inhibitory effect of PGI2 on the secretion of platelets stimulated by a catheter or by venipuncture. Longer infusion of PGI2 did not produce further significant change. The supernate obtained after aggregation of human platelets stimulated by thrombin was injected into monkeys receiving PGI2 infusion. The disappearance of LA-PF4 antigen in monkey plasma followed a biphasic exponential curve with half-lives for the fast and slow components of 8.4 and 63 min. PF4 disappeared faster but followed the same pattern (half-lives for the fast and slow component of 2.1 and 70 min). Analysis of the experimental data suggests that the low levels of secreted platelet proteins in monkey plasma are related to their minimal in vivo release and to their rapid clearance.     

Pulmonary arterial remodeling induced by a Th2 immune response

Pulmonary arterial remodeling characterized by increased vascular smooth muscle density is a common lesion seen in pulmonary arterial hypertension (PAH), a deadly condition. Clinical correlation studies have suggested an immune pathogenesis of pulmonary arterial remodeling, but experimental proof has been lacking. We show that immunization and prolonged intermittent challenge via the airways with either of two different soluble antigens induced severe muscularization in small- to medium-sized pulmonary arteries. Depletion of CD4(+) T cells, antigen-specific T helper type 2 (Th2) response, or the pathogenic Th2 cytokine interleukin 13 significantly ameliorated pulmonary arterial muscularization. The severity of pulmonary arterial muscularization was associated with increased numbers of epithelial cells and macrophages that expressed a smooth muscle cell mitogen, resistin-like molecule alpha, but surprisingly, there was no correlation with pulmonary hypertension. Our data are the first to provide experimental proof that the adaptive immune response to a soluble antigen is sufficient to cause severe pulmonary arterial muscularization, and support the clinical observations in pediatric patients and in companion animals that muscularization represents one of several injurious events to the pulmonary artery that may collectively contribute to PAH.     

Analysis of available diagnostic tests for latex sensitization in an at-risk population

BackgroundLack of a Food and Drug Administration (FDA)–approved skin testing reagent for latex allergy in the United States requires reliance on patient history and serologic assays for diagnosis.ObjectiveTo determine the diagnostic sensitivity, specificity, and predictive values of an FDA-cleared antilatex IgE serology test and an enzyme-linked immunosorbent assay (ELISA) with various sources of latex protein antigens in an at-risk but unselected population of health care workers.MethodsHealth care workers underwent duplicate latex and serologic testing for latex specific IgE with the CAP assay and ELISA from June 1, 1998, through December 31, 2002. Logistic regression with receiver operating characteristic curve analysis determined the values, resulting in 98% and 99% specificity for the CAP assay and ELISA, respectively.ResultsResults of paired skin and serologic tests were available for 792 participants. Forty duplicate skin test results (5%) were positive. For the CAP assay, sensitivity was 35%; specificity, 98%; positive predictive value, 48.3%; and negative predictive value, 96.6%. ELISA demonstrated similar results. Multivariable logistic regression yielding a 98% or 99% specificity for the various ELISAs demonstrated that the adjusted odds of a positive skin test result significantly increased with positive CAP assay and ELISA results using a powdered glove extract.ConclusionsThe performance of the FDA-cleared antilatex IgE serologic test for latex allergy has much lower sensitivity than previously reported. This finding confirms that this serologic test should be used only for patients with a history of latex allergy and not for screening the population with a low prevalence of latex sensitization.     

Immune responses to Aspergillus antigen in IL‐4‐/‐ mice and the effect of eosinophil ablation

BACKGROUND: Exposure to Aspergillus fumigatus allergens results in enhanced total serum IgE and peripheral blood eosinophils in mice. The associated pulmonary inflammation and immunologic responses are comparable to those detected in human allergic bronchopulmonary aspergillosis. Allergen-induced cytokines are thought to regulate the inflammatory and immune responses in these animals. METHODS: In the present study, we exposed C57BL/6 and BALB/c mice to A. fumigatus antigen. Both wild-type and IL-4 knockout phenotypes of animals of both strains were used. Some animals were also treated with anti-IL-5 or anti-IFN-gamma. Total serum IgE, Aspergillus species IgG subclass, peripheral blood eosinophils, and lung histology were studied. RESULTS: The results demonstrate similar lung inflammation in all wild-type and IL-4-/- animals exposed to A. fumigatus antigen. Similarly, in spite of the diverse immune response produced by the anticytokine treatment, no major differences were detected among any of the animal groups studied. CONCLUSIONS: It can be concluded that A. fumigatus exposure in an immunologically unaltered host is predominantly of a Th2 type, and that depletion of the Th2 cytokine leads to a similar lung inflammation but with a characteristic Th1 response, suggesting that the pathogenesis of allergic aspergillosis is the result of multiple induction pathways.     

Clearance of corticosteroids in yearling coho salmon, Oncorhynchus kisutch, in fresh water and seawater and after stress

The metabolic clearance rate of corticosteroids determined after a single injection of [3H]cortisol was higher in fish acclimated to seawater (SW) than in those acclimated to fresh water (FW). Uptake and retention of corticosteroids in liver, gill filaments, and gall bladder bile were greater in SW than in FW fish. The stress of long-term (5 days), but not short-term (12 hr), continuous confinement apparently increased the clearance rate of corticosteroids in both FW and SW fish. Chronic, but not acute, administration of exogenous cortisol, yielding cortisol titers close to the physiological range, appeared to increase the clearance rate of corticosteroids in FW fish.     

Immunopathological response of C57BL/6 and C3H/HeN mice to Aspergillus fumigatus antigens

C3H/HeN and C57BL/6 mice were exposed to culture filtrate (CF) and mycelial extracts (ME) of Aspergillus fumigatus (Af) intranasally. Animals received 6, 8 or 10 biweekly doses and were sacrificed 2 weeks after the last dose was administered. Specific antibodies against Af were detected in their sera by biotin-avidin-linked immunosorbent assay (BALISA). Antibodies against Af belonging to all isotypes showed an increase in both strains of mice. A progressive increase in IgG and IgA antibody isotypes against both CF and ME antigens was detected in C3H/HeN mice during the entire experimental period, whereas most antibody levels peaked after the 8th dose and remained steady or decreased slightly in the C57BL/6 strain. Lung lavage studies showed a relative decrease in the number of macrophages and an increase in the number of lymphocytes after the 6th and 8th instillation of Af antigens in both strains of mice. Histology of the lung demonstrated a progressive inflammatory reaction in C57BL/6 mice during the experimental period. On the other hand, the C3H/HeN mice showed a negligible inflammatory pulmonary reaction. The antibody responses and inflammatory changes detected in the lungs of mice exposed to Af antigens are comparable to allergic bronchopulmonary aspergillosis (ABPA) in humans and hence this model will be of value in understanding the disease mechanism in ABPA and related diseases.     

Effectiveness and Safety of Percutaneous CT-Guided Rib Biopsy

Purpose

To retrospectively evaluate effectiveness and safety of percutaneous CT-guided rib biopsy.