Diabetic ketoacidosis

Glanzmann's thrombasthenia is a bleeding disorder caused by qualitative and/or quantitative defects of platelet membrane glycoprotein (GP) IIb/IIIa complex. The disease is inherited in an autosomal recessive manner. In this paper, cDNA probes were used to study restriction fragment length polymorphisms (RFLPs) in GPIIIa gene. A Taq I polymorphism was identified and this RFLP was composed of variant bands of 6.5 Kb/4.0 and 2.5 Kb with a frequency of 0.46/0.54 in Chinese population. The Taq I polymorphism was further localized by polymerase chain reaction (PCR) method to exon VIII of the GPIIIa gene. In two Glanzmann's thrombasthenia families, the Taq I RFLP studied by both Southern blotting and PCR methods identified the defective GPIIIa gene inherited by patients, and determined the genotype of asymptomatic subjects. Analysis of this Taq I polymorphism by PCR method should be potentially useful in future for the carrier detection and prenatal diagnosis in Glanzmann's thrombasthenia families.     

Acquired Glanzmann's thrombasthenia associated with Hodgkin's lymphoma: a case report and review of the literature

BACKGROUND: Acquired Glanzmann's thrombasthenia is a rare hemorrhagic diathesis resulting from impaired adhesive function of the platelet receptor GPIIb/IIIa (alpha(IIb)beta3). Typically, this disorder develops during adulthood, with patients manifesting fluctuating clinical and laboratory findings. To date, the underlying defect of most if not all cases of acquired Glanzmann's thrombasthenia results from an autoantibody or plasma protein inhibitor directed toward a demonstrably normal GPIIb/IIIa glycoprotein. METHODS: In this report, a patient with a history of treated Hodgkin's lymphoma presented with a severe hemorrhagic diathesis characterized by mild thrombocytopenia, a prolonged bleeding time, and defective platelet aggregation. RESULTS: Examination of the patient's platelet GPIIb/IIIa by Western blot analysis revealed no abnormality. Mixing studies demonstrated a non-immunoglobulin G plasma inhibitory factor, whereas flow cytometry analysis revealed elevated platelet-associated immunoglobulin (Ig) M. After an emergency colectomy for severe hemorrhage, the patient's qualitative and quantitative platelet parameters significantly improved. Pathology of the resected colonic segment demonstrated atypical lymphoid hyperplastic lesions. CONCLUSIONS: To the authors' knowledge, this is the first reported case of acquired Glanzmann's thrombasthenia associated with a putative IgM autoantibody. Furthermore, this report verifies the association of acquired thrombasthenia with lymphoproliferative disease. Although rare, awareness of this hemorrhagic diathesis as a possible sequelae of active or treated lymphoid disorders should encourage clinical vigilance of these patients.     

Characterization of Neisseria meningitidis isolates and clinical features of meningococcal conjunctivitis in ten patients

Genetic defects of the blood platelet membrane glycoproteins, GPIIb-IIIa (alpha IIb/beta 3; CD41/CD61) and GPIb-V-IX (CD42) are the origin of several rare bleeding disorders, the best known of which are Glanzmann's thrombasthenia, Bernard-Soulier syndrome, and platelet-type von Willebrand's disease. In Glanzmann's thrombasthenia, GPIIb-IIIa are missing or defective and platelet aggregation is lacking or reduced. Either gene can be affected and mutations leading to lack of expression or to expression of poorly functional forms have been described. In Bernard-Soulier syndrome, GPIb-V-IX are missing or defective, leading to poor platelet adhesion at high-shear stress to damaged vessel wall and reduced platelet response to thrombin. Mutations in both GPIb alpha (CD42b) and GPIX (CD42a) have been described. Mutations in GPIb alpha can also lead to platelet-type von Willebrand's disease in which GPIb-V-IX are expressed normally but bind von Willebrand's factor spontaneously, which leads to platelet aggregation and thrombocytopenia.     

Extracorporeal lithotripsy in patients with acquired or congenital coagulopathies

Post ESWL haemorragic complications are frequent and most patients experience temporary haematuria and focal intrarenal bleeding or perirenal haematoma are detected by NMR or US imaging. By tradition coagulation troubles have been a contraindication for ESWL but literature describes cases of coagulopathic patients treated with ESWL. From January 1992 to July 1993, 4 of our patients with severe haemostatis troubles (severe haemophilia A in two cases, acquired deficit of coagulation factors and mild thrombocytopenia secondary to post-necrotic hepatitis in 1 case and Glanzmann's thrombasthenia in 1 case) underwent ESWL using Dornier HM3 mod. or MPL 9000. An extensive haematological and clinical evaluation pre and post-ESWL with an adequate haematological prophylaxis (transfusion of blood derivatives) has been performed depending on the coagulation disorder. In our patients we did not observe any haemorragic complication and we propose a reappraisal of the contraindications of ESWL in subjects with coagulation disorders: careful evaluation of haemorragic risk factors, by suitable correction measures and close clinical and instrumental monitoring, allows a reduction of the risk of haemorragic complications in coagulopathic patients who undergo ESWL treatment.     

Linkage of four polymorphisms on the alphaIIb gene

The subunits of the platelet integrin alphaIIb beta3 are encoded by two genes located on chromosome 17. Two pathologies are associated with structural modifications of this complex: Glanzmann's thrombasthenia and alloimmune thrombocytopenia. The former is a hereditary bleeding disorder, the latter is due to an immune response linked to the presence of specific epitopes defined by single amino acid substitutions called human platelet alloantigen (HPA) systems. Analysing the alphaIIb gene from 112 independent chromosomes, we have defined two new silent polymorphisms in complete linkage disequilibrium. They are reciprocally linked to HPA-3 and a previously reported 9 pb deletion in intron 21. Linkage of these four DNA markers spanning a 5 kb fragment of genomic DNA provides a new tool for analysing alphaIIb gene pathology and evolution.     

G-CSF after PBSC transplantation

We report a case of a patient with Glanzmann's thrombasthenia and anti-GPIIb/IIIa alloantibodies who developed life-threatening and intractable bleeding from gastrointestinal telangiectatic lesions. After a period of transfusion-dependent gastrointestinal bleeding despite tranexamic acid, oral iron, omeprazole and platelet transfusions, the use of oral norethisterone produced a significant improvement with a marked reduction in her transfusion requirements.     

Mechanism of platelet aggregation induced by a monoclonal antibody requiring Fc portion

A monoclonal antibody designated Apt4, which is IgG1, was produced by fusion of mouse myeloma cells to spleen cells from a BALB/c mouse immunized with normal human platelets. Apt4 whole IgG caused the aggregation of both platelet rich plasma (PRP) and washed platelets from normal subjects and a patient with Bernard Soulier syndrome but not those from two patients with the Type 1 Glanzmann's thrombasthenia. No aggregation was observed when Apt4 F(ab')2 fragments were used. Immunofluorescence study showed that both whole IgG and F(ab')2 fragments of Apt4 bound to fresh or formalin fixed platelets from normal subjects and a patient with Bernard Soulier syndrome but not to those from two patients with Glanzmann's thrombasthenia. Aggregation induced by Apt4 IgG was inhibited by EDTA (10 mM), PGE1 (1 mM), 2-deoxy-D-glucose/antimycin (1.4 uM), and apyrase (20 units/ml). Preincubation of normal PRP with monoclonal anti-GPIIb/IIIa or anti-GPIb antibodies completely or partially inhibited the Apt4-induced aggregation, whereas anti-GPIIIa antibodies have no effects on this activation. Monoclonal ant-Fc gamma RII antibody (IV.3) inhibited Apt4 induced aggregation. Immunoprecipitation of 125I-labeled platelet membrane lysate by Apt4 IgG showed two protein bands with a molecular weight of 145,000 and 95,000 daltons respectively under non-reducing condition, which are corresponding to GPIIb and GPIIIa. In conclusion, Apt4 antibody binds to GPIIb/IIIa complex and induces aggregation, requiring energy metabolism, calcium, ADP release and Fc portion of IgG to interact with Fc receptor, but independent of thromboxane A2 formation.     

Shear-induced platelet aggregation (SIPA) monitoring of hemostatic effect during platelet transfusion in a patient with Glanzmann's thrombasthenia: a comparison between SIPA and conventional platelet aggregation

Shear-induced platelet aggregation (SIPA) in a patient with Glanzmann's thrombasthenia was examined during platelet infusion therapy. Prior to platelet infusion, SIPA measured with the modified cone-and-plate type viscometer, as well as ADP-and collagen-induced platelet aggregation measured with the conventional platelet aggregometer, were absent. The patient's SIPA after multiple infusions of platelet, in parallel with the bleeding time and the clinical hemostatic effect, improved to the normal level, while ADP-and collagen-induced platelet aggregation remained abnormal. These observations imply that SIPA is physiologically more relevant than the conventional agonist-induced platelet aggregometry in this type of the disease.     

Pseudo-Glanzmann thrombasthenia in the course of autoimmune thrombocytopenic purpura

INTRODUCTION: Auto-immune thrombocytopenic purpura is associated with platelet anti-glycoprotein antibodies, particularly with anti-GPIIb/IIIa complex. Persistence of these antibodies sometimes leads to acquired auto-immune thrombopathy. EXEGESIS: We report the case of a woman treated by splenectomy for auto-immune thrombocytopenic purpura, who developed 5 years later an ecchymotic syndrome despite normal platelet count. High bleeding time and platelet aggregation defect in vitro were evidenced. Following the initial thrombocytopenia, anti-glycoproteins GPIIb/IIIa with lupus anticoagulant and benign monoclonal gammapathy were noticed. Platelet controls showed that hypoaggregant activity was secondary to the persistence of anti-GPIIb/IIa antibodies. CONCLUSION: This acquired auto-immune thrombopathy simulating Glanzmann's thrombasthenia was secondary to the persistence of platelet anti-glycoproteins GPIIb/IIIa.     

Microsporidiosis in a young ostrich (Struthio camelus)

Platelet membrane glycoproteins (GP) IIb/IIa and rap1b, a 21 kDa GTP binding protein, associate with the triton-insoluble, activation-dependent platelet cytoskeleton with similar rates and divalent cation requirement. To examine the possibility that GPIIb/IIIa was required for rap1b association with the cytoskeleton, experiments were performed to determine if the two proteins were linked under various conditions. Chromatography of lysates from resting platelets on Sephacryl S-300 showed that GPIIb/IIIa and rap1b were well separated and distinct proteins. Immunoprecipitation of GPIIb/IIIa from lysates of resting platelets did not produce rap1b or other low molecular weight GTP binding proteins and immunoprecipitation of rap1b from lysates of resting platelets did not produce GPIIb/IIIa. Finally, rap1b was associated with the activation-dependent cytoskeleton of platelets from a patient with Glanzmann's thrombasthenia who lacks surface expressed glycoproteins IIb and IIIa. Based on these findings, we conclude that no association between GPIIb/IIIa and raplb is found in resting platelets and that rap1b association with the activation-dependent cytoskeleton is at least partly independent of GPIIb/IIIa.     

Activation of the fibrinogen binding site on platelets isolated from a patient with the Strasbourg I variant of Glanzmann's thrombasthenia

One proposed ligand binding site on platelet integrin alpha IIb beta 3 is the region of the beta 3 subunit encompassing amino acids 211-221. However, we recently showed that synthetic peptides corresponding to amino acids 211-221 inhibit fibrinogen binding to alpha IIb beta 3 by binding to alpha IIb beta 3 and not to fibrinogen. In this study, we show that AP6, a monoclonal antibody (MoAb) directed against amino acids 214-221 of beta 3, bound to immobilized active alpha IIb beta 3 but did not inhibit fibrinogen binding to the complex. We then determined whether nonfunctional alpha IIb beta 3 on platelets with a beta 3 Arg-214-->Trp mutation (Strasbourg I variant of Glanzmann's thrombasthenia or GTV) could be induced to aggregate after treatment with dithiothreitol (DTT). DTT has been shown to expose the fibrinogen receptor on normal platelets. DTT treatment of GTV platelets did result in the formation of the fibrinogen binding site as indicated by the binding of pI-55, an MoAb that only binds to the activated form of alpha IIb beta 3. Furthermore, DTT-treated GTV platelets aggregated in the presence of fibrinogen and divalent cations. This aggregation was inhibited by EDTA, RGDS, and the selective alpha IIb beta 3 antagonist, Ro 43-5054. These data show that Arg-214 of beta 3 is not required for fibrinogen binding or for platelet aggregation. However, this amino acid appears to be critical for the formation and for the maintenance of the correct tertiary structure of the fibrinogen binding site on alpha IIb beta 3.     

A three amino acid deletion in glycoprotein IIIa is responsible for type I Glanzmann's thrombasthenia: importance of residues Ile325Pro326Gly327 for beta3 integrin subunit association

Glanzmann's thrombasthenia (GT) is a recessive autosomal bleeding disorder characterized by abnormal platelet aggregation due to a qualitative or quantitative defect of the glycoprotein (GP) IIb-IIIa complex (integrin alphaIIb beta3). We describe a new mutation in the GPIIIa gene responsible for type I GT in a consanguineous Algerian family. A discordance between phenotyping and genotyping of the GPIIIa-related HPA-1 platelet alloantigen system in three family members heterozygous for the disease suggested a genetic defect in the GPIIIa gene and a normal GPIIb gene. Sequence analysis of amplified genomic DNA fragments showed a 6-bp deletion in exon 7 of the GPIIIa gene resulting in the amino acid deletion/substitution (Ile325pro326Gly327 --> Met) and creating a new BspHI restriction site. Expression of the mutated integrin beta3 subunit cDNA in Chinese hamster ovary cells showed that the cDNA gene was transcribed into a full-length beta3 protein with an apparent molecular weight identical to wild-type beta3 and accumulated as a single-chain molecule in the cell cytoplasm. The absence of heterodimeric complex formation of the mutant beta3 protein with endogenous alpha v was shown by immunoprecipitation experiments, intracellular immunofluorescent labeling, and a semiquantitative enzyme-linked immunosorbent assay using the alpha vbeta3 complex-specific monoclonal antibodies LM609 and 23C6. Substitution of the methionine residue by a proline, present at position 326 of wild-type beta3, did not restore the ability of the recombinant mutant beta3 protein to associate with alpha v , suggesting that the Ile-Pro-Gly motif is located in a beta3 domain important for integrin subunit interaction. The association of a BspHI restriction site with this newly identified mutation has allowed allele-specific restriction analysis of Algerian GT individuals and the identification of two new unrelated type I patients exhibiting the same mutation, suggesting that the described mutation might be significant in this population and that BspHI restriction analysis will provide a useful screening assay for antenatal diagnosis and genetic counselling.     

Role of surface glycoproteins in human platelet function

Glycoproteins present at the external surface of cells probably play specific roles in cellular function. Increasing evidence suggests that the glycoproteins span the plasma membrane with the bulk of the bound carbohydrate asymmetrically distributed on the outer surface. Micellar association of glycoproteins in membranes leads to pore formation and functional roles in transport through the membrane, while surface glycoproteins have been shown to be enzymes, to determine cell specificity and contribute to the cell surface change. The platelet plasma membrane contains 3 major glycoproteins, glycoproteins I, II and III as characterized in order of their decreasing molecular weight. Glycoprotein I appears to have the highest sialic acid content and to give rise to a platelet specific acidic macroglycopeptide on trypsin digestion. Specific glycoprotein abnormalities in the platelets of patients with Glanzmann's thrombasthenia suggest that the glycoproteins play a role in the mechanism of platelet aggregation. A much reduced content of glycoprotein I in the platelets of 2 patients with the Bernard Soulier syndrome may be associated with their defective adhesion to subendothelium and indicates a possible relationship on the platelet surface with the von Willebrand factor protein. Preliminary evidence suggests that in common with other plasma membranes the platelet membrane has a fluid structure and that the organization of the glycoproteins on the platelet surface is extremely sensitive to stimuli and susceptible to change.     

Ultrastructural analysis of the distribution of the vitronectin receptor (alpha v beta 3) in human platelets and megakaryocytes reveals an intracellular pool and labelling of the alpha-granule membrane

The vitronectin receptor (VnR or alpha v beta 3) belongs to the cytoadhesin subclass of the integrin family. This subclass consists of two receptors which have the beta 3 subunit in common: GP IIb-IIIa complexes (or alpha IIb beta 3) and VnR. We report the subcellular distribution of VnR within human platelets as determined by immunogold staining of ultrathin frozen sections and transmission electron microscopy. Monoclonal antibodies directed against: (i) the alpha v subunit (LM142, AMF7, CLB-706), or (ii) an epitope specific to the complex (LM609) were used. Although VnR is present on platelets, it is a minor component. We therefore first compared several different staining procedures to detect this integrin. Optimal localization of VnR was obtained using a multistep procedure in which biotinylated anti-mouse IgG and a monoclonal anti-biotin antibody provided staining enhancement. Results showed that although present on the surface, alpha v beta 3 was mostly detected in internal membrane systems including those of alpha-granules. Occasionally, platelet sections showed special vesicular structures covered by gold particles. These were often localized at the edge or immediately under the plasma membrane and their origin remains unclear. An internal pool of alpha v beta 3 was confirmed by flow cytometry and by using platelets from a patient with type I Glanzmann's thrombasthenia arising from a GP IIb gene defect. We also investigated the presence of VnR in megakaryocytes (MK) obtained from normal human bone marrow. A fluorescence study showed VnR in small MK with unilobulated nuclei, suggesting that synthesis of this integrin occurs early during megakaryocytopoiesis. In mature cells, VnR expression had decreased relative to GP IIb-IIIa, although intracellular staining was present in EM and alpha-granules were again labelled.     

Costs of blood transfusion: a process-flow analysis

PURPOSE: To determine the cost of transfusing 2 units (U) of packed RBCs at a comprehensive cancer center. METHODS: We performed a process-flow analysis to identify all costs of transfusing 2 U of allogeneic packed RBCs on an outpatient basis to patients with either (1) solid tumor who did not undergo bone marrow transplantation (BMT), (2) solid tumor who underwent BMT, (3) hematologic malignancy who did not undergo BMT, (4) hematologic malignancy who underwent allogeneic BMT, or (5) hematologic malignancy who underwent autologous BMT. We conducted structured interviews to determine the personnel time used and physical resources necessary at all steps of the transfusion process. RESULTS: The mean cost of a 2-U transfusion of allogeneic packed RBCs was $548, $565, $569, $569, and $566 for patients with non-BMT solid tumor, BMT solid tumor, non-BMT hematologic malignancy, allogeneic BMT hematologic malignancy, and autologous BMT hematologic malignancy, respectively. Sensitivity analysis showed that total transfusion costs were sensitive to variations in the amount of clinician compensation and overhead costs, but were relatively insensitive to reasonable variations in the direct costs of blood tests and the blood itself, or the probability or extent of transfusion reaction. CONCLUSION: The costs of the transfusion of packed RBCs are greater than previously analyzed, particularly in the cancer care setting.     

Letter: Alleviation of IUD menorrhagia with ethamsylate

When menorrhagia is associated with an IUD it may be best to advise continuation of the method and prescribe a therapy that can minimize men strual distrubance. Ethamsylate, which has been useful in primary menor rhagia, is undergoing evaluation. It appears to combat excessive menstr ual flow by it hemostatic properties of increasing capillary resistance and reducing bleeding time. In a preliminary study of 13 patients compl aining of menorrhagia associated with IUDs in situ for at least 1 year, menstrual blood loss was estimated based on the iron content of soiled sanitary wear. 500 mg 4 times daily from 5 days before the anticipated onset of menstruation for 10 days was administered. Mean blood loss was 64.8 ml before treatment and 64.6 ml during placebo therapy (p less than .1) but was significantly less (53.5 ml; p less than .05) during ethamsy late therapy. These results suggest that a patient with an IUD in situ who complains of menorrhagia should be treated with ethamsylate.     

Isolated ovarian polyarteritis nodosa

Polyarteritis nodosa is a rare disorder and a form of systemic vasculitis. A 48 year-old female was admitted to the hospital because menorrhagia and pelvic pain in February 1993. The patient underwent exploratory laparotomy resulting in a total hysterectomy and bilateral salpingo-oophorectomy for myoma of uterus and a right adnexal cystic mass. Histopathologic examination revealed left ovarian periarteritis nodosa. Further investigation and 9 months follow-up failed to show any systemic involvement. To our knowledge the isolated ovarian polyarteritis nodosa is the first case in the literature.     

Leiomyoma-related bleeding: a classic hypothesis updated for the molecular era

Leiomyomas are an important cause of menorrhagia and other forms of abnormal uterine bleeding. The pathogenesis of this process is largely unknown, however. A classic theory, first suggested by Sampson's work in 1912 (Surg. Gynecol. Obstet., 14, 215-230), states that local dysregulation of the vascular structures in the uterus is responsible for this abnormal bleeding. Recent work demonstrates dysregulation of a number of growth factors in the myomatous uterus. As many of these factors regulate the process of angiogenesis or have other effects on vascular structures, we hypothesize that this dysregulation of growth factors or their receptors provides the molecular mechanism underlying these vascular abnormalities. In turn, these abnormal vessels lead women with leiomyomas to experience menorrhagia. Factors that may prove to be important in this process include basic fibroblast growth factor, vascular endothelial growth factor, heparin-binding epidermal growth factor, platelet-derived growth factor, transforming growth factor-beta, parathyroid hormone-related protein and prolactin. Current treatment regimens for women with leiomyoma-related bleeding depend on manipulation of the steroid hormone environment. By better understanding the pathogenesis of this disease process, therapies directed against growth factor abnormalities may result in better treatment with less harmful side-effects.     

A new method for measuring menstrual blood loss and its use in screening women before endometrial ablation

OBJECTIVE: 1. To develop and validate a method for measuring menstrual blood loss in a routine setting, and 2. To assess the value of measuring menstrual blood loss before endometrial ablation. DESIGN: A prospective, observational study. SETTING: Four Yorkshire hospitals: The General Infirmary at Leeds, St. James's University Hospital, Leeds, St. Luke's Hospital, Bradford and The Friarage Hospital, Northallerton. PARTICIPANTS: Three hundred and seventy-two women who had been offered endometrial ablation for menorrhagia. MEASUREMENT: Sanitary material was washed with a nonionic detergent in a known volume of water. The haemoglobin in a sample of solution was measured by mixing with sodium carbonate for spectrophotometric analysis. INTERVENTIONS: The menstrual blood loss result was revealed to each women. Electrosurgical endometrial ablation was performed for those who decided to have surgery. MAIN OUTCOME MEASURES: Proportion of women with normal menstrual blood loss (< or = 80 mL) who avoided surgery. Comparison of endometrial ablation outcome in women with and without genuine menorrhagia. RESULTS: Thirty-six women (10%) with normal menstrual blood loss who declined surgery continued to avoid surgery after a mean of 27 months. Two hundred and ninety-two women were followed up for one year after endometrial ablation. Those with genuine menorrhagia (n = 122) were less likely to be dissatisfied (9% vs 18%) (OR 2.5, 95% CI 1.1-4.7) or to require hysterectomy (4% vs 7%) (OR 1.8, 95% CI 0.6-5.2) than women with normal menstrual blood loss (n = 170). CONCLUSIONS: The objective diagnosis of menorrhagia can be undertaken in a routine setting and may provide some women, who have a normal menstrual blood loss, sufficient reassurance to refrain from surgery. Women with genuine menorrhagia have a better outcome after endometrial ablation than those with normal menstrual blood loss.