1/23. Four cases of bleeding diathesis in children due to congenital plasminogen activator inhibitor-1 deficiency.Congenital plasminogen activator inhibitor-1 (PAI-1) deficiency is an extremely rare disorder characterized by a bleeding diathesis that begins in childhood due to hyperfibrinolysis as a result of decreased PAI-1 activity. We now present 4 unrelated pediatric cases of congenital PAI-1 deficiency. All 4 patients had a history of recurrent episodes of subcutaneous bleeding beginning in early childhood. These episodes were characterized by abnormal prolonged bleeding after trauma, tooth extraction, and surgical procedures, as well as by rebleeding following initial hemostasis. The 2 female patients both had symptoms compatible with hypermenorrhea. The family history was positive in 2 of the 4 patients. Hemostatic screening studies in all 4 patients revealed no abnormalities. Testing for factor xiii antigen, von willebrand factor antigen, ristocetin cofactor activity, alpha(2)-plasmin inhibitor (alpha2PI) activity, and plasminogen activity was normal. The euglobulin lysis times were shortened in all cases as compared with those in normal control subjects. None of the patients had elevated tissue plasminogen activator (tPA) antigen levels, but PAI activity was markedly decreased in all cases. Three of the patients also had reduced levels of PAI-1 antigen. There tended to be a reduction in tPA-PAI-1 complex in all cases. In addition, 2 patients had elevated PIC (plasmin-alpha2PI complex). Tourniquet tests were performed in 2 patients, with no appreciable rise in PAI-1 activity or PAI-1 antigen levels. The administration of tranexamic acid clearly improved hemorrhagic symptoms in these patients. We considered PAI-1 deficiency to be the likely etiology of the congenital bleeding diatheses in these 4 cases.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |
2/23. Acquired factor viii inhibitor in a patient with chronic myelogenous leukemia receiving interferon-alfa therapy.OBJECTIVE: To report a case of an acquired factor viii inhibitor associated with the use of interferon-alfa. CASE SUMMARY: A 58-year-old white man with newly diagnosed chronic myelogenous leukemia (CML) was initially treated with hydroxyurea. Interferon-alfa therapy was started six weeks later in order to enhance the response, with gradual reduction and eventual discontinuation of hydroxyurea. Interferon-alfa was continued for one year. Following bone marrow aspiration at one year, the patient developed significant bleeding and bruising at the site of extraction. His hemoglobin decreased from 11.3 to 9.3 g/dL and his activated partial thromboplastin time was elevated at 72 seconds. The factor viii concentration was 0.02 units/mL; factor viii inhibitor concentration was 58 Bethesda units. A diagnosis of an acquired factor viii inhibitor was made, and the patient was treated with activated factor VII concentrates and prednisone. Interferon-alfa was discontinued, and the inhibitor subsequently disappeared over the next six weeks. The patient did not have any further bleeding problems. DISCUSSION: Acquired factor viii inhibitors other than in patients with hemophilia are rare. To date, there are no reported cases of factor viii inhibitors associated with CML. Moreover, the temporal association with interferon-alfa administration suggests a causal relationship. There are only two previous case reports suggesting interferon-alfa as a cause of factor viii inhibitors. CONCLUSIONS: Induction of factor viii inhibitors is a serious potential complication of therapy with interferon-alfa. We suggest that a diagnosis of an acquired factor viii inhibitor be considered in patients who experience unexplained bleeding with interferon-alfa therapy.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |
3/23. afibrinogenemia: first identification of a splicing mutation in the fibrinogen gamma chain gene leading to a major gamma chain truncation.Congenital afibrinogenemia is a rare autosomal recessive disorder characterized by the complete absence of plasma fibrinogen and by a bleeding tendency ranging from mild to moderately severe. Beside a deletion of the almost entire Aalpha-chain gene, only 2 missense mutations in the C-terminal domain of the Bbeta-chain have been very recently described as being associated with afibrinogenemia. We studied a Pakistani patient with unmeasurable plasma levels of functional and immunoreactive fibrinogen. Sequencing of the fibrinogen genes revealed a homozygous G-->A transition at position 5 of intron 1 of the gamma-chain gene. The predicted mutant fibrinogen gamma-chain would contain the signal peptide, followed by a short stretch of aberrant amino acids, preceding a premature stop codon. To demonstrate the causal role of the identified mutation, we prepared expression vectors containing a region of the fibrinogen gamma-chain gene spanning from exon 1 to intron 4 and carrying either a G or an A at position 5 of intron 1. Transient transfection of the mutated plasmid in hela cells, followed by rna extraction and reverse transcriptase-polymerase chain reaction (RT-PCR) analysis, allowed us to demonstrate the production of an erroneously spliced messenger rna (mRNA), retaining intron 1, as shown by direct sequencing. A normal splicing occurred in hela cells transfected with the wild-type plasmid. This is the first report of a mutation in the fibrinogen gamma-chain gene causing afibrinogenemia and indicates that, in addition to the Aalpha and Bbeta-chain genes, the gamma-chain gene must also be considered in mutation screening for afibrinogenemia.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |
4/23. Late removal of dense posthemorrhagic vitreous membranes following cataract extraction.Severe, seemingly permanent intraocular hemorrhages caused by ocular trauma, Eales' disease and retinal vein thrombosis, lead to late formation of a dense retrolental membrane, vitreous liquefaction and intumescent cataract with faulty light perception. In the absence of ultrasound, the diagnosis was made possible only after removal of the cataract. Lens extraction and excision of the vitreal membrane led to surprisingly good recovery of vision. Three cases are presented and the pathological study of a posthemorrhagic membrane.- - - - - - - - - - ranking = 5keywords = extraction (Clic here for more details about this article) |
5/23. Use of recombinant factor viia to treat persistent bleeding following dental extractions in two cirrhotic patients.BACKGROUND AND OBJECTIVES: A single dose of recombinant factor viia (rFVIIa) has been shown to be effective and safe in correcting the prothrombin time (PT) in cirrhotic patients, but no clinical data exists demonstrating its efficacy in arresting active bleeding. MATERIALS AND methods: rFVIIa was used in two cirrhotic patients for persistent bleeding following dental extractions despite repeated treatment at the wound site and, in one case, repeated administrations of fresh-frozen plasma (FFP). RESULTS: Bleeding stopped promptly in both patients after administration of rFVIIa. However, bleeding recurred in the patient who had not received concomitant treatment at the extraction sites. No recurrence of bleeding was observed in the second patient, who underwent local treatment 15 min after rFVIIa. CONCLUSIONS: Recombinant factor viia arrested bleeding after dental extractions in two cirrhotic patients who had been unsuccessfully treated with FFP. However, additional local treatment is needed to limit the risk of recurrence as a result of the short half-life of rFVIIa.- - - - - - - - - - ranking = 7keywords = extraction (Clic here for more details about this article) |
6/23. Low-dosage intravenous immunoglobulin in the management of a patient with acquired von Willebrand syndrome associated with monoclonal gammopathy of undetermined significance.We report herein the case of a 69-year-old Japanese man with acquired von Willebrand syndrome associated with monoclonal gammopathy of undetermined significance who developed IgG1-kappa antibodies against von willebrand factor (VWF). The patient was urged to undergo tooth extractions because of alveolar pyorrhea, and a low-dosage intravenous immunoglobulin (IV-Ig) therapy (0.3 g of IgG/kg/day for 3 days) was chosen for him. On the 4th day after the infusion, VWF antigen and VWF ristocetin cofactor increased to 40 and 78% of the control, respectively, and dental extractions were performed successfully. On the 7th day, these values reached a maximum, i.e. 95 and 160% of the control, respectively. Then, they quickly decreased to 35 and 75% on the 10th day, and 6 months later, they became 16 and <3% of the control, respectively. Upon analysis of plasma VWF multimers (VWFMs) in this patient, those with large to medium molecular masses more selectively disappeared before the IV-Ig infusion than did those with small molecular masses. On the 4th day, the pattern of VWFMs was completely normalized and appeared to persist until the 10th day. Six months later, a small amount of large to medium-sized VWFMs was still present, but at 7-8 months, the pattern of VWFMs became almost the same as that before infusion. Throughout the patient's clinical course, the activity of plasma VWF-cleaving protease, which specifically cleaves the Tyr842-Met843 bond of the subunit and reduces its multimeric sizes, was quite normal (95-119%). These results provided consistent evidence that the selective absence of VWFMs with large to medium molecular masses in this patient is caused by the heightened clearance of a complex of IgG inhibitor and VWFMs from the circulation, presumably through IgG binding to the Fc receptor of macrophages. Furthermore, these results also indicated that a low-dosage IV-Ig therapy is effective enough for hemostatic management for programmed surgery.- - - - - - - - - - ranking = 2keywords = extraction (Clic here for more details about this article) |
7/23. The management of glaucoma in nanophthalmos.patients with nanophthalmos are prone to develop a chronic painless type of glaucoma in middle age, probably due to the natural increase in the size of the lens which is already relatively too large for the small eye. Although the underlying mechanism is obscure, a slowly progressive "creeping" chronic angle-closure is postulated, but gonioscopic evaluation is difficult due to the shallow anterior chamber, with grade I and slit angles. Response to medical treatment is poor and miotics may even make the condition worse by producing relative pupillary block and by relaxing the lens zonule. Ordinary glaucoma surgery is to be avoided in nanophthalmos because of the fear of postoperative ciliary-block malignant glaucoma. Periopheral iridectomy performed in five eyes at an advanced stage of the chronic angle-closure did not facilitate glaucoma control in three eyes, and in two eyes in which the operation was combined with posterior sclerotomy, the eyes became blind from vitreous hemorrhage. Lenx extraction in five eyes controlled the glaucoma but was followed by choroidal effusion and nonrhegmatogenous retinal detachements in two eyes and blindness in another eye when combined with a posterior sclerotomy. No firm therapeutic recommendations can be made on the basis of the author's experience in the six reported cases. Conventional medical therapy seems ineffectual even when begun early in the glaucoma. Conventional glaucoma surgery must be performed early, before permanent damage to the outflow mechanism occurs but removal of the lens must be anticipated. The surgeon must also remain aware of the high incidence of serious posterior-segment complications which inexplicably follow glaucoma or lens surgery in nanophthalmos, as described by Brockhurst.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |
8/23. Experience of desmopressin (DDAVP) administration in patients with congenital and acquired bleeding disorders.Desmopressin (DDAVP) 0.3 micrograms/kg was administered intravenously to three normal volunteers and 12 patients with von Willebrand's disease (vWD), congenital or acquired platelet function defect, or uremic bleeding to assess its effects and side effects. DDAVP significantly shortened the bleeding time as compared with basal values. The mean peak post-DDAVP level of factor viii coagulant activity increased 5.9 /- 0.5 (mean /- SEM) fold, von willebrand factor antigen increased 3.7 /- 0.3 fold, von willebrand factor ristocetin cofactor activity increased 4.6 /- 0.6 fold and the tissue-type plasminogen activator antigen increased 3.4 /- 0.6 fold. Analysis of the multimeric structure of the von willebrand factor revealed that type I vWD had complete correction after DDAVP infusion transiently. Except for a mild drop in both systolic and diastolic blood pressures, few side effects were noted. By concomitant intravenous infusion of DDAVP and oral administration of tranexamic acid, we successfully treated two cases of type I vWD undergoing tooth extraction, and one case of acquired bleeding disorder undergoing a biopsy of a mandibular mass, and a uremic patient complicated by intractable traumatic hematuria. Our experiences confirmed that most patients with vWD and some patients with congenital or acquired bleeding disorders can be treated effectively by DDAVP infusion without the need for plasma product replacement. In this study we found that a patient with a variant form of type I vWD had prolongation of the bleeding time, thrombocytopenia and platelet aggregation after DDAVP infusion.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |
9/23. Unplanned extracapsular cataract extraction in postvitrectomy eyes.A 70-year-old man, a 59-year-old woman, and a 57-year-old woman underwent pars plana vitrectomy. In all three cases, cataracts developed in the eyes that had been operated on. During cataract extraction, which included massage of the globe after retrobulbar anesthesia and a conventional ab externo incision, loss of lens material into the vitreous cavity occurred in all three postvitrectomy eyes.- - - - - - - - - - ranking = 5keywords = extraction (Clic here for more details about this article) |
10/23. The management of dental extractions in cases of thrombasthenia complicated by the development of isoantibodies to donor platelets.Two cases of thrombasthenia, a rare hereditary disorder of platelet function, are presented. The oral surgical and dental management of these cases is discussed in the light of the development of isoantibodies to transfused platelets in one of the cases and in another case encountered. The problems of obtaining donor platelets matched for platelet and HL-A antigens are discussed. Emphasis is placed on the use of local hemostatic measures and antifibrinolytic agents in the management of hemorrhage in this disorder and the avoidance of platelet transfusions as far as possible. Conservative dentistry and early preventive dental advice are considered desirable in order to avoid extractions.- - - - - - - - - - ranking = 5keywords = extraction (Clic here for more details about this article) |
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