We present the case of a 19 year-old Caucasian female with history of systemic lupus erythematosus (SLE) and normal baseline kidney function who developed severe acute renal failure following treatment of thrombocytopenia with the thrombopoietic agent romiplostim. Percutaneous kidney biopsy revealed thrombotic microangiopathy (TMA) without immune complex lupus glomerulonephritis. We discuss pathogenesis and differential diagnosis of TMA in patients with SLE and raise concerns regarding the use of thrombopoietic agents in such patients. Based on favorable long-term outcome in our case aggressive treatment and in particular prolonged use of plasma exchange in these patients are advocated.

Recently, Pickard et al reported decreased "capping" in lymphocytes from patients with Duchenne type muscular dystrophy (DMD) as well as female carriers of the DMD trait. To resolve subsequent debate about the reproducibility of this finding, we carried out a "blinded" collaborative study designed to eliminate the possibility of observer bias. Blood samples from DMD patients, their mothers, and controls were obtained and coded at Johns Hopkins and transported to the Medical College of Virginia, where lymphocyte capping was tested using FITC-labeled polyvalent anti-human immunoglobulin. Diminished capping in lymphocytes was found in 12 of 13 DMD patients (17 of 18 blood samples) and in 14 of 17 mothers of DMD patients (19 of 23 blood samples), as compared with 8 of 21 control subjects (8 of 22 blood samples). The results in both the patient and the carrier groups differed significantly from those in the control group, confirming previous observations of diminished lymphocyte capping in DMD. The findings provide support for the concept of a systemic defect associated with cell membranes in this disorder. The relatively high incidence of false positive results limits the usefulness of lymphocyte capping as a diagnostic test for carriers under the conditions of this study.

#3053 Background: HER2, estrogen (ER) and progesterone receptors (PR) are important markers for prognostic and therapeutic implications in breast cancer. Fluorescence in situ hybridization (FISH) and IHC for HER2 gene amplification and evaluation of ER and PR in primary tumor are commonly used methods. However, evaluation of these markers in lymph nodes or distant metastases, which may be more biologically significant, is not that applicable in regular clinical basis. In the current work we compared HER2 (by FISH), ER and PR (by IHC) in matched primary breast carcinomas and lymph node metastases.
 Design: Formalin fixed, paraffin embedded tissue sections from 39 cases of primary and lymph node metastases were assessed for Her2 (by FISH). Primary tumors of the cases selected were known to be HER2 un-amplified. Also, ER and PR IHC were performed on 36 cases from the same cohort of cases to assess any discrepancy between primary and lymph node metastases of these cases.
 Result: Out of 39 cases, one case was HER2 amplified in lymph node metastasis compared to un-amplified primary tumor. Eight percent of cases (3/36) were ER negative in LN mets and 6% (2/36) were less strongly positive compared to the positive primary tumors. Nineteen percent (7/36) were PR negative in LN mets in contrast to the matched positive primary tumors. Regarding PR immunoreactivity, 6% (2/36) were PR-positive in LN met compared to their corresponding negative primary tumors.
 Conclusion: While most matched primary breast tumors and lymph node metastases show concordance in HER2, ER, PR status, we found discordance in a minority of cases. These results suggest the possibility that extension of studies in metastatic breast tumors in parallel with that of primary lesions is informative and can be used to determine further treatment options and predict prognosis in breast cancer patients. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3053.