Drug-induced chest pain and myocardial infarction. Reports to a national centre and review of the literature

Objectives: To analyse reports of drug-induced myocardial infarction and chest pain sent to a national reporting centre. To review which drugs were suspected of exhibiting these adverse events and what mechanisms were involved. Methods: During the 20-year period 1975 through 1994, a total of 19 141 reports on adverse reactions to drugs were received by the Netherlands Centre for Monitoring of Adverse Reactions to Drugs. Of these 19 141 reports, 220 (1.1%) were concerned with drug-induced chest pain or myocardial infarction. After excluding reports in which the causal relationship was unlikely, poorly documented reports and reports on cases of overdosage, 183 reports (84%) were analysed. Results: There were 130 reports (71%) of drug-induced chest pain and 53 reports (29%) of drug-induced myocardial infarction. A total of 104 reports concerned females (57%). The most frequently reported suspected drugs were the antimigraine drug sumatriptan (33 reports, 4 concerning myocardial infarction), the calcium antagonist nifedipin (9 reports, 2 of myocardial infarction) and nicotine [9 reports (8 patches, 1 chewing gum), 5 concerning myocardial infarction]. There were 18 reports of a fatal outcome. Conclusions: Several drugs can produce chest pain or myocardial ischaemia. It is important to recognise drugs as a potential cause, especially in patients with normal coronary arteries. Received: 17 February 1997 / Accepted in revised form: 26 May 1997     

Posttransfusion purpura associated with an autoantibody directed against a previously undefined platelet antigen

Although alloantibody against the PLA1 platelet antigen is usually found in patients with posttransfusion purpura (PTP), the mechanism of destruction of the patient's own PLA1-negative platelets is unexplained. We used a sensitive immunoblot technique to detect antiplatelet antibodies in a patient with classic PTP. The patient's acute-phase serum contained antibodies against three proteins present in control (PLA1-positive) platelets: an antibody that bound to a previously unrecognized platelet protein of mol wt 120,000 [glycoprotein (GP) 120], antibodies that bound to PLA1 (mol wt 90,000), and an epitope of GP IIb (mol wt 140,000). The antibodies against PLA1 and GP IIb did not react with the patient's own PLA1-negative platelets, control PLA1-negative platelets, or thrombasthenic platelets. In contrast, the antibody against GP 120 recognized this protein in all three platelet preparations, but not in Bernard-Soulier or Leka (Baka)-negative platelets. Antibody against GP 120 was not detected in the patient's recovery serum, although the antibodies against PLA1 and GP IIb persisted. F(ab)2 prepared from the patient's acute-phase serum also bound to GP 120. These results suggest that in PTP, transient autoantibody production may be responsible for autologous (PLA1-negative) platelet destruction. In addition, alloantibodies against more than one platelet alloantigen may be found in this disease. The nature of the GP 120 autoantigen and the GP IIb-related alloantigen defined by our patient's serum remains to be determined.     

Family history of atopy and clinical course of RSV infection in ambulatory and hospitalized infants

Respiratory syncytial virus (RSV) infection can be severe in pediatric patients. Risk factors for severe disease include age less than 6 months, prematurity, preexisting heart or lung disease or malformations, gastroesophageal reflux, and immunodeficiency. The aim of the present study was to investigate the influence of family history of allergy on the clinical course of RSV infection in ambulatory and hospitalized infants. In a retrospective study, 172 patients younger than 12 months of age (99 inpatients and 73 outpatients) were enrolled. Information was obtained from hospital charts and from questionnaires sent to pediatricians. Inpatients had a significantly higher rate of atopy in their family history than outpatients, 62% and 29%, respectively (P < 0.001). Bronchiolitis was diagnosed more frequently in patients with an atopic burden than those without, 89% versus 74%, respectively (P < 0.02). Inpatients with an atopic family history had a significantly longer hospital stay than those without such a history, 7.4 +/- 3.7 days and 6.1 +/- 2.3 days, respectively (P < 0.04). Factors other than age that are considered a risk for severe infection with RSV (prematurity, preexisting heart or lung disease or malformation, and gastroesophageal reflux) were not confirmed in the present study. We conclude that infants with a family history of atopy are at increased risk for severe RSV infection as indicated by higher rates of hospitalization, longer hospital stay, and more frequent occurrence of bronchiolitis.     

Performance characteristics of the new ARCHITECT Toxo IgG and Toxo IgG Avidity assays

The ARCHITECT Toxo IgG and IgG Avidity assays have been developed as a fully automated panel for immune status determination and acute infection exclusion. Resolved relative specificity and sensitivity of the ARCHITECT Toxo IgG assay were 99.6% (1359/1365) and 99.7% (1096/1099) as determined on pregnant females, blood donor, and diagnostic specimens. Seroconversion sensitivity of the ARCHITECT assay was comparable with the AxSYM Toxo IgG assay. The ARCHITECT Toxo IgG Avidity assay detected 100.0% (124/124) of acute phase specimens (<4 months after infection) as low avidity, whereas the Vidas Toxo IgG Avidity assay detected 98.9% (89/90) as low avidity. In summary, the ARCHITECT Toxo IgG assay, using recombinant antigens, showed excellent specificity and sensitivity for acute phase as well as past infection specimens. The ARCHITECT Toxoplasmosis panel can be reliably used to rule out acute Toxoplasma gondii infection in pregnant women.     

Superior Biochemical Recurrence and Long-term Quality-of-life Outcomes Are Achievable with Robotic Radical Prostatectomy After a Long Learning Curve—Updated Analysis of a Prospective Single-surgeon Cohort of 2206 Consecutive Cases

Background

Our earlier analysis suggested that robot-assisted radical prostatectomy (RARP) achieved superiority over open radical prostatectomy (ORP) in terms of positive surgical margin (PSM) rates and functional outcomes.

Preclinical assessment of purging with VP-16-213: key role for long- term marrow cultures

An evaluation of the effects of VP-16 on normal human marrow cells and representative lymphoma-leukemia cell lines was performed to assess this agent's applicability to ex vivo marrow purging. Tumoricidal dose curves were defined using malignant lymphoid (SK-DHL2 and Reh) and myeloid (HL-60) cells admixed with a 20-fold excess of irradiated marrow cells to simulate a borderline remission marrow. One-hour treatments yielded ID50 of less than 5 mumol/L of VP-16 for clonogenic units from each cell line; rare-to-zero clonogenic units survived exposure to 50 to 100 mumol/L. CFU-Mix, BFU-E, and CFU-GM were equal in their sensitivity to VP-16 (ID50s25 to 30 mumol/L). Marrows treated with 75 mumol/L were completely depleted of these colony-forming cells but produced CFU-GM in one-stage long-term marrow cultures (LTMCs). This dose had little adverse effect on the proliferative capacity of marrow stromal progenitors, as measured by CFU-F (ID50 271 mumol/L) and by the unperturbed development of adherent layers in LTMCs. Furthermore, these stromal layers were able to support hematopoiesis as well as controls in co-culture experiments with autologous marrow cells (two-stage LTMCs). In conclusion, doses of VP-16 that cleanse marrow of lymphoma-leukemia cells spare hematopoietic and stromal progenitors as demonstrated by LTMCs. These data favor the use of VP-16 in the clinical autotransplant setting.     

Molecular characterization of quinine/quinidine drug-dependent antibody platelet interaction using monoclonal antibodies

Two murine monoclonal antibodies, FMC 25 and AN 51, directed against distinct epitopes on the glycoprotein Ib complex, have been used to further define the mechanism of quinine/quinidine drug-dependent antibody interaction with platelets. FMC 25, directed against an epitope on glycoprotein IX, had no effect on platelet aggregation induced by collagen or adenosine diphosphate and little, if any, effect on ristocetin-induced platelet agglutination. FMC 25 and its (Fab)2 fragment, however, were potent inhibitors of drug-dependent antibody- induced platelet aggregation and blocked binding of drug-dependent antibody to platelets as assessed by indirect platelet immunofluorescence. In contrast, AN 51, directed against an epitope on the alpha-subunit of glycoprotein Ib, blocked ristocetin-induced, factor VIII/von Willebrand factor (FVIII/vWF)-dependent platelet agglutination but not drug-dependent antibody-induced platelet aggregation or binding of drug-dependent antibody to platelets. Selective proteolytic removal of the majority of the alpha-subunit of glycoprotein Ib (glycocalicin) from platelets by treatment with calcium- dependent protease did not affect binding of drug-dependent antibody. In addition, a quinidine-dependent antiplatelet antibody immunoprecipitated glycoprotein Ib complex from normal platelets and the membrane-associated proteolytic remnant of the glycoprotein Ib complex from calcium-dependent protease-treated platelets. Preincubation of drug-dependent antibody with purified glycoprotein Ib complex inhibited subsequent binding of antibody to platelets, but the separated components, glycoprotein Ib and glycoprotein IX, were both ineffective, suggesting that the normal interaction between glycoprotein Ib and glycoprotein IX in the intact complex was necessary for drug-dependent antibody recognition. The functional response of platelets to drug-dependent antibody was not mediated by way of platelet Fc receptor, since aggregation of washed platelets by acetone- aggregated IgG was not inhibited by FMC 25 (Fab)2. FVIII/vWF was not required for drug-dependent antibody-induced platelet aggregation. The combined evidence is consistent with quinine/quinidine-dependent antibody-platelet interaction occurring by way of a FVIII/vWF- independent, Fc receptor-independent mechanism that probably involves binding of antibody to glycoprotein IX or the beta-subunit of glycoprotein Ib or both.     

A simple laboratory alternative to irreversibly sickled cell (ISC) counts

Irreversibly sickled cells (ISC) are considered to be a hallmark of sickle cell disease, yet their number in peripheral blood smears varies greatly among different homozygous SS patients. This variation has suggested a role for ISC in the varying clinical manifestations of the disease. Efforts to determine the role of ISC have been complicated by the difficulty in standardizing the quantification of these cells. For this reason, we have attempted to develop an alternative method of quantification that would be less variable than the microscopic counting of cells on blood smears. Because ISC are dehydrated dense cells, a measurement based on cell density seemed an attractive alternative approach. Analysis of whole blood samples on a simple, 2- step density gradient, spun in a microhematocrit centrifuge, showed a strong correlation between the proportion of high density cells and the percentage of morphologically identified ISC. Parallel ektacytometric measurements of cell deformability, another parameter that reflects the low water content and high MCHC of ISC, were also strongly correlated with ISC counts. These findings suggest that either of these measurements, sensitive to the special physical properties of ISC, could be used as an objective substitute for the microscopic counting of ISC.