Severe hemolytic anemia post-renal transplantation produced by donor anti-D passenger lymphocytes: case report and literature review.

The passenger lymphocyte syndrome (PLS), often associated with immune-mediated hemolytic anemia after solid organ and hematopoietic stem cell transplantation, is the result of concomitant transplantation of donor lymphocytes along with the donor allograft. Antibodies directed against recipient red blood cells (RBCs) are frequently found in ABO-mismatched solid organ transplants; however, passenger lymphocyte-mediated hemolysis due to Rh-incompatible antibodies has only rarely been reported. In this report, we present a case of severe hemolytic anemia related to the PLS in an ABO-matched renal allograft recipient. The recipient's blood type was A Rh(D) positive; and the donor, who had been previously alloimmunized, was A Rh(D) negative. The renal allograft recipient's hemoglobin abruptly decreased on postoperative day 12 in the setting of a newly positive direct antiglobulin test and anti-D antibodies in the plasma. The patient required intermittent RBC transfusions for ongoing hemolysis during the first 6 months post-renal transplant. Of all reported cases of anti-D-mediated PLS, our patient would seem to have been one of the most severe, as indicated by a nadir hemoglobin of 41 g/L and the need for 23 U of transfused RBCs. A hemolytic anemia occurring after organ transplantation should raise the possibility of donor-derived antibodies directed against the recipient RBCs. Passenger lymphocyte syndrome-associated hemolysis is occasionally severe as in our case, but can be effectively treated with compatible RBC transfusions.

Differentiating arrhythmogenic right ventricular cardiomyopathy from right ventricular outflow tract ventricular tachycardia using multilead QRS duration and axis.

BACKGROUND: Ventricular tachycardia (VT) resulting from arrhythmogenic right ventricular cardiomyopathy (ARVC) may be difficult to differentiate from idiopathic right ventricular outflow tract (RVOT) VT. OBJECTIVES: The purpose of this study was to investigate the hypothesis that QRS characteristics would be different in ARVC because of altered conduction through abnormal myocardium. METHODS: In 24 RVOT VT patients (18 women and 6 men; age 42 +/- 10 years) and 20 ARVC patients (12 women and 8 men; age 38 +/- 14 years), mean QRS duration, frontal plane axis, and precordial R-wave transition were measured in 12-lead ECGs recorded during VT. RESULTS: Mean QRS duration was longer in all 12 leads in ARVC patients. A significant difference was noted in leads I, III, aVL, aVF, V(1), V(2), and V(3) (P <.05). Leads I and aVL had the largest mean difference between ARVC and RVOT VT patients of 17.6 +/- 4.7 ms and 15.8 +/- 7.5 ms, respectively (P <.0001). Lead I QRS duration > or =120 ms had a sensitivity of 100%, specificity 46%, positive predictive value 61%, and negative predictive value 100% for ARVC. The area under the receiver operating characteristic (ROC) curve was 0.89. The addition of mean QRS axis <30 degrees (R

3D ultrasound measurement of change in carotid plaque volume: a tool for rapid evaluation of new therapies.

BACKGROUND AND PURPOSE: New therapies are being developed that are antiatherosclerotic but that lack intermediate end points, such as changes in plasma lipids, which can be measured to test efficacy. To study such treatments, it will be necessary to directly measure changes in atherosclerosis. The study was designed to determine sample sizes needed to detect effects of treatment using 3D ultrasound (US) measurement of carotid plaque. METHODS: In 38 patients with carotid stenosis >60%, age+/-SD 69.42+/-7.87 years, 15 female, randomly assigned in a double-blind fashion to 80 mg atorvastatin daily (n=17) versus placebo (n=21), we measured 3D plaque volume at baseline and after 3 months by disc segmentation of voxels representing carotid artery plaque, after 3D reconstruction of parallel transverse duplex US scans into volumetric 3D data sets. RESULTS: There were no significant differences in baseline risk factors. The rate of progression was 16.81+/-74.10 mm3 in patients taking placebo versus regression of -90.25+/-85.12 mm3 in patients taking atorvastatin (P<0.0001). CONCLUSIONS: 3D plaque volume measurement can show large effects of therapy on atherosclerosis in 3 months in sample sizes of approximately 20 patients per group. Sample sizes of 22 per group would be sufficient to show an effect size of 25% that of atorvastatin in 6 months. This technology promises to be very useful in evaluation of new therapies.