Hepatitis C viral load does not predict disease outcome: going beyond numbers

The analysis of 58 patients with chronic hepatitis C without cirrhosis and treated with interferon-alpha demonstrated that hepatitis C viral (HCV) load does not correlate with the histological evolution of the disease (p = 0.6559 for architectural alterations and p = 0.6271 for the histological activity index). Therefore, the use of viral RNA quantification as an evolutive predictor or determinant of the severity of hepatitis C is incorrect and of relative value. A review of the literature provided fundamental and interdependent HCV (genotype, heterogeneity and mutants, specific proteins), host (sex, age, weight, etc) and treatment variables (dosage, time of treatment, type of interferon) within the broader context of viral kinetics, interferon-mediated immunological response (in addition to natural immunity against HCV) and the role of interferon as a modulator of fibrogenesis. Therefore, viral load implies much more than numbers and the correct interpretation of these data should consider a broader context depending on multiple factors that are more complex than the simple value obtained upon quantification.     

Association between the blood pressure response to a change in posture and the 6-year incidence of hypertension: prospective findings from the ARIC study

The association between the blood pressure response to a change from the supine to the standing position and the 6-year incidence of hypertension was studied in a bi-ethnic, middle-aged cohort of 6951 normotensive men and women free of coronary heart disease at baseline. Postural change in systolic blood pressure (SBP) was categorized into deciles, and the middle four deciles served as the referent (no change) group. In unadjusted analyses, the incidence of hypertension was higher among both those with SBP increases and decreases relative to those in the referent group. Associations were modestly attenuated after controlling for age, ethnicity, and gender and cardiovascular disease risk factors. However, after adjustment for baseline, seated SBP, a modest association with incident hypertension persisted only for SBP decreases. Orthostatic hypotension (upon standing) was associated with incident hypertension and isolated systolic hypertension and, unexpectedly, this increased risk was highest among those with the lowest levels of baseline, resting SBP.     

Comprehension during informed consent in a less-developed country

Few practical guidelines exist on how to ensure that research participants in less-developed countries understand the consent form before enrollment. In a study of HIV-1 transmission in Haiti, participants were required to pass an oral examination on the contents of the consent form with a passing score of 12/15 (80%) before enrollment. 15 individuals were given information during a single meeting with a physician, and three (20%) passed. 30 subsequent volunteers were given information by a counsellor during three meetings, and 24 (80%) passed. Formal assessment of research participants' comprehension of the consent form should be considered as a routine step in the informed consent process in less-developed countries.     

Functional and morphologic evaluation of congenital urinary tract dilatation by using combined static-dynamic MR urography: findings in kidneys with a single collecting system

PURPOSE: To assess combined static-dynamic magnetic resonance (MR) urography in the evaluation of congenital urinary tract dilatation in infants and children. MATERIALS AND METHODS: Sixty-two patients with urinary tract dilatation underwent prospective examination with combined static-dynamic MR urography. A combination examination involved use of a static T2-weighted three-dimensional inversion-recovery fast spin-echo sequence and a dynamic T1-weighted two-dimensional fast field-echo sequence with gadopentetate dimeglumine-DTPA and furosemide application. Twelve additional patients underwent examination with only static MR urography. Thus, both image quality and morphologic features were assessed in 74 patients with the use of MR urography. The results were compared with those of ultrasonography and, when available, conventional urography or surgery. In 62 patients, the dynamic sequence was used to calculate split renal function from renograms generated from parenchymal regions of interest and to assess urinary excretion from whole-kidney renograms. Results were compared with those of diuretic renal scintigraphy (DRS) for split function (Spearman rank correlation coefficient) and urinary excretion (kappa coefficient). RESULTS: Stenoses at the ureteropelvic (n = 33) and ureterovesical (n = 31) junctions and within the ureter (n = 3) and nonstenotic dilatation (n = 23) were clearly depicted, while the normal urinary tract (n = 51) was depicted in its entirety in 47 of 51 examinations. Image quality was considered good or excellent in 95% of the kidney-ureter units. For split renal function, dynamic MR urography and DRS showed significant correlation (r = 0.92, P <.001). For urinary excretion, MR urography and DRS showed strong agreement (kappa = 0.67), with concordant classification of urinary excretion in 59 (81%) of 73 abnormal kidney-ureter units and in all 47 (100%) normal kidney-ureter units. CONCLUSION: Combined static-dynamic MR urography provides high-quality depiction of the urinary tract in infants and children, while allowing accurate determination of single-kidney function and reliable evaluation of urinary excretion.     

Tuberculosis of the hip as the presenting sign of HIV and simulating pigmented villonodular synovitis

A 36-year old man, with no prior known exposure to human immunodeficiency virus (HIV) or tuberculosis, presented with monoarticular pain and a decreased range of motion in his left hip. Radiography and magnetic resonance imaging revealed bony erosive lesions, juxta-articular cysts, a large effusion, and juxta-articular edema. The initial clinical and radiographic diagnosis was pigmented villonodular synovitis (PVNS) of the left hip. However, what was initially felt to be a chronic proliferative inflammatory process was later determined to be tuberculous arthritis. This case emphasizes the importance of including tuberculous arthritis in the differential diagnosis of patients with monoarticular destructive joint disease radiologically suggestive of PVNS.     

Proton magnetic resonance spectroscopy with metabolite nulling reveals regional differences of macromolecules in normal human brain

PURPOSE: To quantify the macromolecular content in different anatomic brain regions and to evaluate an age dependency of the macromolecular concentrations. MATERIAL AND METHODS: A short echo time Stimulated Echo Acquisition Mode (STEAM) sequence was used without and with inversion recovery metabolite nulling in 8-12 healthy volunteers. Quantitation was achieved by an extended LCModel, and macromolecular resonances at 0.9, 1.4, 2.1, and 3.0 ppm were evaluated. RESULTS: In the cerebellum, the 1.4, 2.1, and 3.0 ppm resonances were highest compared to all other regions (P < 0.02); the 0.9 ppm resonance was significantly higher than that of pons (P < 0.01). In the motor cortex, the 0.9, 1.4, and 2.1 ppm resonances were higher than those of white matter and pons (P < 0.02). Pons and white matter did not differ significantly from each other. A significant correlation of the macromolecular concentrations with the age could not be found. CONCLUSION: There were higher macromolecular concentrations in the cerebellum and motor cortex than in pons or white matter. These were probably due to the higher portions of gray matter in these volumes of interest (VOIs) than in the other regions.     

A validation trial of subdermal injection compared with intraparenchymal injection for sentinel lymph node biopsy in breast cancer

Sentinel lymph node (SLN) biopsy is increasingly being used as an accurate and less morbid surrogate for axillary dissection. However, a standardized technique in the biopsy of SLNs is not used. Some authors propose subdermal injection to be as accurate as peritumoral intraparenchymal injection (IPI). Our objective is to determine whether the SLNs identified by subdermal injection truly represent SLNs and match those found with IPI. Specific end points of the study were 1) successful localization of the SLN by the IPI of isosulfan blue or the radiocolloid intradermal injection, 2) successful uptake of radiocolloid and isosulfan blue on individual SLN, and 3) determination of the frequency with which the radiocolloid injection detected the "gold standard" blue SLN. SLNs were found in 71 of 73 cases (success rate = 97%). Blue SLNs were identified in 64 patients (88%). SLNs in 61 patients (84%) were radioactive. A total of 112 SLNs were identified in 71 patients (1.6 nodes/patient). Seventy-six of 87 SLNs found with IPI were also radioactive (concordance of 87%). All SLNs harboring metastatic cancer (16 patients) were found by both techniques, being both blue and radioactive. Our results support the concept of shared lymphatic pathways in the breast with a high degree of communication between the subdermal lymphatics and the intraparenchymal lymphatics. The success in identification of the SLN is made simpler and improved by the addition of subdermal radiocolloid injection.