Chondromalacia patellae: assessment with MR imaging

Magnetic resonance (MR) images of the posterior patellar hyaline articular cartilage were obtained in 23 subjects to determine if MR imaging could accurately demonstrate the patellar cartilage. Arthroscopy was used as the standard of reference. Three subjects were asymptomatic volunteers. In the remaining 20 who had patellofemoral pain, arthroscopy was performed before MR imaging in seven and afterward in 12; one did not undergo arthroscopy. MR imaging showed focal areas of swelling of the patellar cartilage, focal hypointensity, surface irregularity, areas of thinning, and areas of cartilage loss with exposure of subchondral bone. The surgical findings agreed with those from MR images in all seven patients who underwent arthroscopy before MR imaging and in ten of the 12 who underwent surgery afterward. MR imaging is an accurate means of examining the posterior patellar cartilage and should be considered as an alternative to diagnostic arthroscopy when chondromalacia patellae is suspected.     

Suprapancreatic biliary obstruction: CT evaluation

In a 5-year period, 92 patients with biliary obstruction proximal to the pancreatic segment were evaluated with computed tomography (CT). Seventy-three were judged to have technically optimal studies. Observations of the level of obstruction were compared with data from 50 percutaneous transhepatic cholangiograms; CT data enabled the level of obstruction to be correctly predicted in 46. CT enabled correct prediction of the distribution of obstructing lesions in all 18 patients with intrahepatic obstruction. Forty-four of the 73 patients had pathologic examination of the porta hepatitis. CT findings of obstructing mass and lesser omental nodes resulted in correct prediction of malignancy in 25 (92%) of 27 patients; the absence of such findings enabled correct prediction of benign disease in 13 (77%) of 17 individuals. CT is most valuable as a noninvasive means of planning surgical or radiologic drainage procedures in patients with biliary obstruction.     

Confirmation of hepatitis C infection: a comparison of five immunoblot assays

BACKGROUND: Recently, new immunoblot assays for the detection of antibodies to hepatitis C virus (HCV) became available. STUDY DESIGN AND METHODS: The performance of five confirmatory anti-HCV immunoblot assays was studied with samples with known HCV antibody and HCV RNA status. The assays were a third-generation strip recombinant immunoblot assay (RIBA-3, Chiron Corp., Emeryville, CA), a second-generation HCV blot (DB-2 blot, Diagnostic Biotechnology, Singapore), the Wellcozyme HCV Western blot (Murex blot, Murex Diagnostics, Dartford, UK), an immunodot HCV assay (Matrix, Abbott Laboratories, Chicago, IL), and the third-generation HCV line immunoassay (Liatek-III, Organon Teknika, Boxtel, The Netherlands). RESULTS: Sensitivity on samples from 48 HCV RNA-positive, second-generation RIBA (RIBA-2)-positive persons and specificity on samples from 31 low-risk donors was 96 percent or better for all assays. The sensitivity on 31 HCV RNA-positive, RIBA-2- indeterminate samples was as follows: Liatek-III, 94 percent; RIBA-3, 90 percent; Murex blot, 61 percent; Matrix, 55 percent; and DB-2 blot, 39 percent. In testing 39 HCV RNA-negative, RIBA-2-indeterminate donor samples, the percentage found to be negative was Liatek-III, 77 percent; RIBA-3, 67 percent; Murex blot, 49 percent; DB-2 blot, 33 percent; and Matrix, 15 percent. The order of sensitivity on four HCV seroconversion series was (from high to low): RIBA-3, Liatek-III, DB-2 blot, Murex blot, and Matrix; the differences were small. CONCLUSION: Detection of HCV antibodies was not refined by the addition of new HCV antigens (NS5, E2/NS1), but by improved classical antigens (core, NS3, NS4). Replacement of the commonly used RIBA-2 will resolve the status of a high proportion of RIBA-2-indeterminate samples.     

The provision of renal replacement therapy for adults in England and Wales: recent trends and future directions

We assessed the level of provision of renal replacement therapy for adults in England and Wales. All autonomous main renal units in England (n = 52) and Wales (n = 5) were surveyed in 1996. Data for England were compared to the 1993 National Renal Review. The acceptance rate in England 1995 was 82 (80-85) per million population (p.m.p.) compared with 67 (65-70) p.m.p. in 1991-2. The rate in 1995 in Wales was 109 (98- 122) p.m.p. The prevalence rate in England was 476 p.m.p. at end-1995 compared to 393 p.m.p. in 1993, in Wales it was 487 p.m.p. The number of main renal units in England did not rise between 1993 and 1995; capacity was increased by use of more treatment shifts and temporary haemodialysis stations, and by opening more satellite units. The main growth was in hospital haemodialysis. There was an uneven geographical distribution of services. Patients accepted were older with more comorbidity. The use of better-quality processes of dialysis increased. The steady-state position for RRT will not be reached for over a decade. Health authorities will face continued pressure to fund increases in quantity and quality improvements. A stronger evidence base of the effectiveness of therapies, and a national registry to monitor the equity and cost-effectiveness of services are needed.      

Coagulation parameters of CPD fresh-frozen plasma and CPD cryoprecipitate-poor plasma after storage at 4 degrees C for 28 days

A pilot study was performed on the storage of plasma and cryosupernatant plasma at 4 degrees C for up to 28 days. Eight bags, four of CPD fresh-frozen plasma (FFP) and four of CPD cryosupernatant plasma (CSP, plasma without cryoprecipitate), were sampled during storage for assays of pH; factors V, VIII, IX, and XI; fibrinogen; prothrombin time; activated partial thromboplastin time (APTT); plasma protein electrophoresis; viscosity; and C1q binding. No changes were found in viscosity or the plasma protein electrophoretic pattern, and there was no detectable immune complex formation. The fibrinogen concentration remained constant, and the prothrombin time showed a gradual increase of 2.5 seconds for both groups of plasma. The labile coagulation factor V decreased gradually for FFP and CSP to 58 and 64 percent of its initial value, respectively (51 +/− 8% and 54 +/− 6% of the value of fresh pooled plasma). Factor VIII decreased to 36 percent of its initial value in FFP (48 +/− 14% of fresh pooled plasma). In CSP, factor VIII decreased after 28 days to 7 percent of its initial value (7 +/− 1% of fresh pooled plasma). The APTT increased for FFP from 28 to 35.8 +/− 1.1 seconds and for CSP from 36 to 49.5 +/− 4.9 seconds. The only chemical change observed for both plasmas was a rise in pH, from 7.27 to 7.56, after 28 days. The results of this pilot study indicate that FFP can be stored at 4 degrees C for 28 days with sufficient recovery of coagulation factors to maintain hemostasis.(ABSTRACT TRUNCATED AT 250 WORDS)     

Thrombosis in inflammatory bowel disease: clinical setting, procoagulant profile and factor V Leiden

Patients with inflammatory bowel disease have an increased frequency of thromboembolism, and microvascular thrombosis has been proposed as a contributory pathogenic factor. The mechanism of enhanced procoagulant activity is not understood. We examined the clinical setting of thromboembolic events in 52 patients with Crohn's disease or ulcerative colitis, and assessed the procoagulant laboratory profile, including Factor V Leiden, in a subset of 20 patients to identify procoagulant risk factors. Patients who developed thrombosis tended to be young; 60% of thrombotic events occurred in patients under 50 years. Multiple thromboembolic episodes occurred in 13% and unusual sites of thrombosis (e.g. intracardiac, cerebral, inominate veins) in 11%. No risk factor was identifiable in 52% of cases and two-thirds of thromboses occurred in an out-patient setting. The mortality rate was 8%. Evidence for inflammatory disease activity was found in only 45% of patients with ulcerative colitis at the time of the thromboembolic event, in contrast to 89% of those with Crohn's disease. Assays for specific coagulation defects were negative in all cases tested (protein S, C were normal in 17/17; anti-thrombin III, anti-phospholipid antibodies and activated protein C resistance were negative in 20/20, and only 1/20 patients was found to be heterozygous for Factor V leiden. Thrombosis in inflammatory bowel disease is important because it occurs in a young population, often in unusual sites, and has a high mortality. The development of thrombosis is related to active inflammatory disease in most patients with Crohn's disease but apparently not in those with ulcerative colitis. Since approximately half of the patients had no other identifiable risk factor, there remains a substantial group of patients with IBD who develop thrombosis for unknown reasons.