Detection of clonal platelet antibodies in immunologically-mediated thrombocytopenias: association with circulating clonal/oligoclonal B cells

Summary Aware that T and B cells in autoimmune thrombocytopenia are abnormal, including the existence of clonal B cell populations, we sought to characterize this clonal phenomenon in various immunological thrombocytopenias using platelet antibody light chain analysis, flow cytometry, Southern blot analysis, and PCR. Using a monoclonal antibody-antigen capture ELISA, we analysed sera from 21 of 26 patients with autoimmune, alloimmune. or drug-induced immunological thrombocytopenia for the light chain phenotypes of their platelet antibodies. Alloantibodies and drug-dependent antibodies from four and 14 patients, respectively, were found that expressed a predominant type of light chain, suggesting that these platelet-reactive antibodies were monoclonal or oligoclonal in nature. 14 of the 26 patients were available for light chain B cell phenotyping studies. Of these 14 patients, thrombocytopenia was due to autoimmunity in two, drug-induced immunity in four, and alloimmunity in eight. We detected clonal populations of B cells in all 14 patients by flow cytometry. Although six of these latter patients possessed platelet antibodies with clonal characteristics, light chain phenotypes of antibodies in five patients were opposite to those of their B cells. Eight of these patients were further examined for immunoglobulin gene rearrangement using Southern and/or polymerase chain reaction analysis. In all eight patients we detected clonal or oligoclonal B cell populations. Only two of these patients had malignancies (chronic lymphocytic leukaemia) that would be expected to have detectable clonal B cells, and thus the mechanism for clonal expansion in the other six patients did not appear to he related to an obvious neoplastic process. Prior to these studies, detection of clonal B cells in thrombocytopenic patients without known malignancies was limited to individuals with autoimmune thrombocytopenia, prompting the speculation that this particular autoimmune disorder arises from B cell dysregulation, rather than from expansion of specific autoantibody producing B cell clones. In contrast, the current studies provide evidence that clonal B cells are common to patients with any form of immunologically-mediated thrombocytopenia. Moreover, the majority of the platelet antibodies (86%) present in these disorders exhibited monoclonal characteristics in that there was an apparent restriction in light chain usage.     

Therapeutic endoscopic retrograde cholangiopancreatography: what the future holds

These are exciting times for interventional endoscopists performing ERCP. The advent of noninvasive, diagnostic techniques of the pancreaticobiliary tree has resulted in a shift toward more therapeutic procedures. The combination of major technologic advances together with endoscopists' growing comfort with invasive procedures has helped to push the boundaries of endoscopic therapy. These therapies, however, should always be sanctioned by sound science and well-controlled clinical trials.     

Liver disease in alpha 1-antitrypsin deficiency: a review

Alpha 1-antitrypsin deficiency is an inherited metabolic disorder that predisposes the affected individual to chronic pulmonary disease, in addition to chronic liver disease, cirrhosis, and hepatocellular carcinoma. Just over one-third of genetically susceptible adult patients with the most severe phenotype, PiZZ, develop clinically significant liver injury. The clinical presentation of liver disease is variable, and the genetic and environmental factors that predispose some individuals to liver disease while sparing others are unknown. The mechanisms of liver and lung disease are distinct and unique. This article reviews the liver disease associated with alpha 1-antitrypsin deficiency, emphasizing the genetic defect, molecular pathogenesis, natural history, and promising therapies.     

A self-administered family history questionnaire improves identification of women who warrant referral to genetic counseling for hereditary cancer risk

Objectives

This study was undertaken to assess a self-administered family history questionnaire in order to better identify women within a gynecologic oncology practice for referral to genetic counseling services.

Methods

Returning patients at an outpatient gynecologic oncology clinic completed a self-administered family health history questionnaire and a detailed telephone interview. A genetic counselor separately assessed blinded information garnered from the questionnaire, structured genetic interview, and electronic medical records to determine whether these data warranted referral to genetic counseling based on established criteria. The structured genetic interview was considered the gold standard to which the questionnaire and medical record information were compared.

Results

Of the 45 total participants in the study, 26 (58%) were identified from the structured genetic interview as meeting criteria for referral to genetic counseling. The questionnaire identified 21 (81%) of these 26 referrals, while the medical record identified 13 (50%) of these 26 referrals. This led to a 62% increase in referral capture by the questionnaire. The median time to complete the questionnaire was 17 min (range 5-57 min). Thirty-four participants (75.6%) had more family members with cancer identified on the questionnaire compared to the electronic medical record. The questionnaire identified fewer family members with cancer in the five cases that were missed for appropriate referral.

Conclusions

Current standard clinical practices are insufficient at identifying patients in need of referral to genetic counseling. A self-administered questionnaire improves recognition of candidates for genetic counseling in a gynecologic oncology practice.     

Mycophenolate mofetil monotherapy in liver transplant recipients: a single center experience.

The long-term use of calcineurin inhibitors (CIs) is associated with significant morbidity in liver transplant recipients. Although mycophenolate mofetil (MMF) is well tolerated, two small studies reported an unacceptable rate of acute allograft rejection in liver transplant recipients receiving MMF monotherapy. In this study, we retrospectively investigated the safety and efficacy of MMF monotherapy in liver transplant recipients. We reviewed the medical records of all patients who underwent liver transplant at our institution. Sixteen patients were identified who received MMF either as monotherapy (n = 13) or with corticosteroids (n = 3; 2 of them for other comorbid conditions), and these patients were studied to determine the efficacy and complications. Fifteen (15/16) patients were converted from a CI to MMF because of renal insufficiency. Patients were converted to MMF monotherapy after a median of 2,056 days (range, 606-5,893) after liver transplantation. The median postconversion follow-up was 668 days (range, 60-1,509). Four patients required dialysis despite conversion; of those patients not requiring dialysis, serum creatinine stabilized and showed a trend toward improvement (2.51 +/- 1.12 mg/dL to 1.85 +/- .58 mg/dL, P = .1). However, there were 3 episodes (47, 107, and 1,203 days after conversion) of severe, irreversible allograft rejection after conversion resulting in death in 2 patients and necessitating retransplantation in 1 patient. There were no patient characteristics, except perhaps African-American race, that predicted the development of rejection. In conclusion, MMF monotherapy was associated with a significant risk (19%) of unpredictable, severe, and irreversible allograft rejection even among long-term transplant survivors. Caution should be exercised before converting patients to MMF monotherapy.     

Renal Insufficiency May Partly Explain Chronic Anemia in Patients Awaiting Liver Transplantation

In patients with cirrhosis, anemia is common and is likely to be multifactorial, including decreased erythrocyte production, sequestration due to hypersplenism, hemolysis, and increased blood loss from gastrointestinal bleeding. Renal dysfunction is also common in liver disease and this may also cause anemia. However, an association between anemia and renal dysfunction has not been reported in patients with cirrhosis. Our objective was to determine whether anemia in cirrhotic patients is independently related to renal dysfunction. We conducted a retrospective chart review of patients in our institution listed for liver transplantation. We collected simultaneous data on age, hemoglobin, creatinine, albumin, liver enzymes, prothrombin time, and bilirubin. We excluded patients who were hospitalized or deceased to avoid confounding variables. Two hundred eighty-six (female n = 130) patients with a mean age of 52.8 +/- 9.7 (range, 18-73) years were studied. Renal dysfunction (creatinine > 1.2 mg/dL) was present in 55 (19%) patients, and anemia (hemoglobin < 12 g/dL) was seen in 115 (40%) patients. Anemia was more common in patients with renal dysfunction (64 versus 34%; P < 0.001) compared to those with normal renal function. Creatinine, prothrombin time, and bilirubin showed an inverse relationship (all P's < 0.001) with hemoglobin, and albumin showed a positive correlation with hemoglobin (P < 0.001). Multivariate analysis showed that creatinine (OR, 2.4; 95% CI, 1.05-5.3; P = 0.038), prothrombin time (P = 0.026), bilirubin (P = 0.035), and albumin (P = 0.001) were independent predictors of anemia. Renal dysfunction is an important cause of anemia in patients with cirrhosis. The role of erythropoietin in the management of anemia in patients with cirrhosis and renal dysfunction should be explored in prospective studies.     

Memory impairment and the mediating role of task difficulty in patients with schizophrenia

Using meta-analytic methods, we sought to synthesize the research literature on memory impairment in schizophrenia. Additionally, we compared performances across memory measures to determine if task difficulty (e.g., effortful encoding and retrieval vs non-effortful encoding and retrieval) could account for variance across studies. Our primary measures of interest included the California Verbal Learning Test, Wechsler Memory Scale, Rey Auditory Verbal Learning Test, Hopkins Verbal Learning Test, Rey–Osterrieth Complex Figure Test, and the Benton Visual Retention Test. We searched for all studies that met inclusion criteria using PubMed, PsycINFO, Scholars Portal Search, and Google Scholar. Studies were included if: (i) they were published after 1980; (ii) healthy controls were compared to patients with schizophrenia; (iii) at least one of the noted measures of interest was employed in the primary study; and (iv) the primary study included data that could be transformed to point estimate effect sizes (i.e., Cohen's d). Cohen's d was calculated between patients and healthy controls, along with overall 95% confidence intervals. A two-tailed independent samples t-test was conducted to assess if performance differed on various paired subtests of the same domain. Large effect sizes were found for all memory tests. No significant differences were found between subtests. In conclusion, patients with schizophrenia experience significant verbal and visual memory impairments, which are not explained by task difficulty. Patients were unable to learn or retrieve more reliably despite repetition and cuing strategies, suggesting that memory impairment in the illness is not a function of task difficulty.