A case of acquired transient bleeding diathesis associated with acquired platelet storage pool deficiency and defective thromboxane A2 production.

Acquired disorders of platelet function are an underdiagnosed cause of bleeding tendency. A 14-year-old girl developed moderate mucocutaneous bleeding two weeks after a Mycoplasma pneumoniae infection successfully treated with clarithromycin. The patient was referred to us 7 months later for laboratory investigation of the persisting bleeding diathesis. The patient's personal and family histories were negative for bleeding disorders. Complete blood count, von Willebrand Factor levels and coagulation tests were normal; platelet aggregation, ATP secretion, δ-granules content and serum thromboxane B2 levels were defective. At follow-up visits, laboratory parameters and the bleeding diathesis progressively normalized within 2 years. The patient's condition is compatible with a diagnosis of acquired Storage Pool Deficiency (SPD), associated with defective thromboxane A2 production. To our knowledge, this is the first case of acquired, transient SPD with spontaneous remission. The pathogenic role of Mycoplasma pneumoniae infection or clarithromycin is possible, albeit uncertain.

Experience With Pre-procedural Hemostatic Medications versus Platelet Transfusion in Patients With Platelet Storage Pool Deficiency.

BackgroundStorage pool deficiency (SPD) is a rare bleeding disorder characterized by reduction in the number of delta granules within platelets, interfering with hemostasis. Current literature lacks well-designed studies from which to draw concrete conclusions regarding pre-procedural management of bleeding complications. Objective: The purpose of this study is to describe bleeding and safety outcomes of SPD patients receiving either pre-procedural platelet transfusions or platelet-sparing regimens. Methods: An exploratory retrospective cohort study was conducted among SPD patients, comparing major bleeding events between those who received platelet transfusion and those who received desmopressin, tranexamic acid, and/or aminocaproic acid within 24 hours prior to procedure. Results: Rates of major bleeding were not found to be higher among patients who received a platelet-sparing regimen [platelet-sparing: 2/25 (8%); platelet transfusion: 2/29 (6.9%); P = .99]. Incidence of non-major bleeding was higher in the platelet transfusion group, but this was not statistically significant [platelet-sparing: 0/25 (0%); platelet transfusion: 3/29 (10.3%); P = .24]. Treatment-related adverse effects were observed following 8 of 54 procedures (14.8%). Conclusion: Use of a platelet-sparing regimen was not associated with a significantly higher incidence of major or non-major bleeding events. Future prospective trials are recommended to compare outcomes between therapies.

Variation in Platelet Delta Granules Over Time in Young Women Undergoing Evaluation for Heavy Menstrual Bleeding.

Delta-granule platelet storage pool deficiency (δ-PSPD) is a qualitative platelet function defect associated with variable bleeding phenotypes. Platelet electron microscopy (EM) is commonly utilized to evaluate for δ-PSPD, but intrapatient variability in platelet δ-granule numbers by EM is currently unknown. Fifteen young women aged 11 to 17 years presenting to a young women's hematology clinic for the evaluation of heavy menstrual bleeding underwent platelet EM testing at their initial hematology clinic visit and at 1 and 3 months later. Platelet aggregation of platelet-rich plasma by light transmission was also performed on all patients at their initial visit. Eight patients had average δ-granules per platelet consistently ≥2. Three patients were found to have average δ-granules per platelet <2 on initial testing, 2 of which reverted to ≥2 on subsequent testing. When initial average δ-granules per platelet was ≥2, initial repeat testing remained so in 83% (95% confidence interval [CI], 52%-98%) of cases and subsequent repeat testing remained so in 75% (95% CI, 43%-95%) of the cases. Platelet aggregation testing was abnormal in 53% of patients, and there was no apparent correlation between platelet EM findings and platelet aggregation testing. In this small group of young women presenting for the evaluation of bleeding symptoms, we found that almost half of the patients had substantial variability in platelet EM results. Given other identified limitations in platelet EM testing, and the intrapatient variability identified in this study, providers should use caution in utilizing EM in isolation to diagnose δ-PSPD.

Postural orthostatic tachycardia syndrome is associated with platelet storage pool deficiency.

Mechanisms have been postulated to explain postural orthostatic tachycardia syndrome (POTS), however, the etiology of this often debilitating disorder remains unknown. We conducted a retrospective case-control study of 181 POTS patients who exhibited/reported bleeding symptoms for a specific platelet (PL) dysfunction disorder, delta granule storage pool deficiency (δ-SPD).Patients were included only if results of blood tests for δ-SPD were available. Electron microscopy was utilized to diagnose δ-SPD. An ELISA assay was used to determine serotonin (5HT) concentration in PLs and medical record review was employed to collect patients' clinical symptoms.The most common bleeding symptom was easy bruising (71%) but frequent nose bleeds, heavy menstrual bleeding, and a family history of bleeding were also commonly reported. Of the patients studied, 81% were diagnosed with δ-SPD. Our investigation of 5HT concentration extracted from PLs revealed significantly lower levels of 5HT in POTS patients when compared to that of control subjects. Our data suggest that patients with POTS have significant comorbidities including bleeding symptoms and/or family bleeding histories, and have diminished PL 5HT levels supporting the hypothesis that POTS is a low 5HT level disorder. While we describe a significant relationship with POTS and δ-SPD, this finding does not constitute an etiology for POTS.Our results establish an additional comorbidity frequently seen in POTS that could explain a number of disparate symptoms often affecting the severity of POTS.

Menstrual bleeding patterns and prevalence of bleeding disorders in a multidisciplinary adolescent haematology clinic.

Heavy menstrual bleeding (HMB) is a frequent complaint in adolescence. Although HMB is often caused by immaturity of the hypothalamic-pituitary-ovarian axis, bleeding disorders are another common yet often unidentified cause. The aim of this study was to examine the bleeding patterns and prevalence of inherited bleeding disorders among females referred for HMB to a multidisciplinary adolescent haematology clinic. We retrospectively reviewed the first 105 patients (ages 8-18 years) referred to this specialty clinic from February 2009 to December 2011. Using menstrual bleeding questionnaires and medical records, data were extracted regarding demographics, bleeding patterns, frequency and types of bleeding disorders identified, and prescribed interventions. Sixty-two per cent of patients were diagnosed with a bleeding disorder, including platelet storage pool deficiency (36%), von Willebrand's disease (9%), other platelet function defect (8%), Ehlers-Danlos syndrome (7%) and combined bleeding disorders (2%). Comparison of the bleeding profiles for females with and without a bleeding disorder revealed only three factors that were significantly different, including the reported regularity of patients' periods (P = 0.02), description of period flow (P = 0.04) and number of days of each period that the bleeding was described as 'heavy' (P = 0.007). Bleeding disorders are prevalent in adolescent females presenting to a specialty clinic. Specifically, a relatively high proportion of adolescents were diagnosed with platelet storage pool deficiency. In our small population, menstrual bleeding profiles, as examined by a standardized questionnaire, could not identify females with an underlying bleeding disorder, demonstrating the important role of haemostasis testing in the evaluation of adolescents with HMB.

The use of thromboelastography for the peripartum management of a patient with platelet storage pool disorder.

We describe the peripartum management of a 26-year-old primigravida with a platelet storage pool disorder who underwent spontaneous vaginal delivery of twins with epidural analgesia. Postpartum hemorrhage from uterine atony, and cervical and vaginal lacerations were treated successfully with 1-desamino-8D-arginine vasopressin and blood products. The use of thromboelastography in the assessment and management of bleeding risk in the setting of platelet storage pool disorder is described.

Platelet structural pathology in a patient with the X-linked GATA-1, R216Q mutation.

The ultrastructural pathology of GATA-1, V205M and G208S macrothrombocytes was discussed in earlier investigations. This study has used the same technology to evaluate macrothrombocytes from a patient with the GATA-1, R216Q mutation. Some of the pathological features observed in macrothrombocytes from patients with the V205M and G208S variations including hypo- and agranular platelets, tubular inclusions and platelets within platelets, as well as platelets within platelets within platelets were identified. However, tubular membrane sheets in megakaryocytes and platelets of the V205M and G208S types and large groups of platelets attached to platelets to form megathrombocytes were not observed. The unique pathology of the megathrombocytes from this patient was the near absence of dense bodies in his giant cells. Storage Pool Deficiency, together with large platelets, defective adhesion and aggregation of his macrocytes under shear stress to vWF and collagen and defective clot retraction may contribute to the pathogenesis of his bleeding disorder.

Alpha-delta platelet storage pool deficiency in three generations.

Alpha-Delta platelet storage pool deficiency (alphadelta SPD) is a rare inherited bleeding disorder affecting both males and females, occurring in families, as well as sporadically. Patient platelets in most cases are moderately deficient in both alpha granules and dense bodies. Only one patient has been severely deficient in both organelles. The present study is the first to document a severe decrease in both platelet alpha granules and dense bodies in four members in three generations of the same family. Efforts to differentiate this disorder from other hypogranular platelets syndromes in the present investigation suggested that the alpha granules and dense bodies become connected to channels of the open canalicular system (OCS) and lose their contents to the exterior without prior activation of the cells. In contrast, alpha granule formation in the white platelet syndrome is too slow, and cells leave the bone marrow still in the process of producing organelles. Gray platelet syndrome platelets can make alpha granules, but their enclosing membranes are unable to retain stored products. As a result, the organelles lose their contents to surrounding cytoplasm in megakaryocytes and platelets, not selectively through the demarcation system channels and OCS channels. Thus, the pathogenesis of alphadelta SPD is unique.

delta-Storage pool disease: a pitfall in the forensic investigation of sudden anal blood loss in children: a case report.

We present the case of a 3.5-year-old boy with sudden anal blood loss at school. Sexual abuse was suspected, and, apart from anal fissures seen on sigmoidoscopy, no other clinical signs of any sort of disorder were present. As no medical explanation for the blood loss could be given, penetrating anal trauma was suggested. During follow-up consultations, there were complaints of occasional blood loss. Platelet aggregation tests and electron microscopy finally helped diagnose a delta-storage pool disease which is a rare haemostatic disorder involving the dense granules of the platelets. Although exclusion of well-known blood diseases through routine laboratory testing is a common practice in children with sudden blood loss, this case illustrates the value of more specialised investigation both from a diagnostic and forensic point of view.

Mild hypoxia causes severe pulmonary hypertension in fawn-hooded but not in Tester Moriyama rats.

The purpose of this study was to test whether the Tester Moriyama rat (TMR), a strain that has a serotonin platelet storage-pool deficiency similar to that of the fawn-hooded rat (FHR), develops severe pulmonary hypertension (PH) upon exposure to mild hypoxia. We compared hemodynamic parameters in catheterized 10-week-old FHR, TMR, and control Wistar rats that had been raised from birth to 10 weeks of age under normoxia (PI(O(2)) approximately 150 mmHg) or mild hypobaric hypoxia (PI(O(2)) approximately 120 mmHg). Mean pulmonary artery pressure and right ventricle to left ventricle plus septum weight ratio were much higher in the mildly hypoxic FHR compared with the normoxic FHR. These parameters were only increased slightly by exposure to mild hypoxia in the TMR and Wistar rats. Mild hypoxia did not affect mean systemic artery pressure in any of the rat strains. Exposure of FHR to mild hypoxia from 4 to 10 weeks of age did not lead to development of PH. Endothelin-1 (ET-1) mRNA and peptide levels were increased in the hypertensive lungs of mildly hypoxic FHR compared with the normotensive lungs of normoxic FHR, and of normoxic and mildly hypoxic TMR and Wistar rats. These results suggest that mild hypoxia causes severe PH and upregulation of lung ET-1 expression in neonatal FHR but not in neonatal TMR, and that the period from birth to 4 weeks of age is critical for the development of the severe PH in the FHR. A serotonin PSPD does not predispose rats to hypoxia-induced PH.

Recurrent haemoperitoneum in a mild von Willebrand's disease combined with a storage pool deficit.

Haemoperitoneum secondary to haemorrhagic corpus luteum has been described in severe bleeding disorders such as afibrinogenaemia, type 3 von Willebrand's disease and patients under oral anticoagulation. We have studied one patient who presented three episodes of severe bleeding at ovulation, requiring surgery twice, with the diagnosis of mild von Willebrand's disease and mild storage pool deficiency. Mild von Willebrand's disease (associated with other thrombopathies or coagulopathies) should be considered in this pathology, although physicians would prefer to find a severe haemorrhagic disorder as the underlying condition in these cases.

Monthly haemoptysis in a woman with platelet storage pool disease.

A 26-year-old female with known platelet storage pool disease presented with a short history of recurrent haemoptysis. Initial investigations were unhelpful until the cyclical nature of the symptoms became apparent prompting the unusual diagnosis of pulmonary endometriosis to be made. This was subsequently confirmed on premenstrual CT scanning. The introduction of a specific hormonal therapy and multidisciplinary input was ultimately successful.

Acquired delta-storage pool deficiency associated with idiopathic myelofibrosis.

A 73-year-old woman complained of easy bruising, as a consequence of prolonged bleeding time despite normal platelet counts. Platelet aggregation profile, mepacrine fluorescence test, flow cytometry and transmission electron microscopy studies led to the diagnosis of delta-storage pool deficiency (SPD) A few months later, she developed hyperleucocytosis with immature granulocytes and erythroblasts. The presence of bone marrow fibrosis and clonal cytogenetic abnormalities led to the diagnosis of idiopathic myelofibrosis (IM). Association between SPD and IM has never been reported. The pathogenesis of this unusual association remains unclear and may involve proliferation of abnormal monoclonal stem cells with differentiation into activated megakaryocytes associated with impaired dense granule development and increased cytokines release which may be. involved in myelofibrosis.

[Thrombocytic alpha-delta-storage-pool-disease: shortening of bleeding time after infusion of 1-desamino-8-D-arginine vasopressin]. / Alpha-delta-storage-pool-disease der Thrombozyten: Verkürzung der Blutungszeit durch Gabe von 1-Desamino-8-D-Arginin-Vasopressin (DDAVP).

BACKGROUND: The synthetic vasopressin derivate desmopressin (1-desamino-8-D-arginine vasopressin) has been reported to shorten the bleeding time in patients with hemophilia A, von Willebrand's disease and several functional platelet disorders. In addition to substitution of platelets, vasopressin is therefore used to prevent bleeding complications. CASE: We report the case of a 14-year-old female patient with prolonged bleeding time due to the rare thrombocytic alpha-delta-storage-pool-disease. When normal donor platelet substitution alone was ineffective, bleeding time was normalised after infusion of desmopressin and elective wisdom-tooth extraction was performed without significant postoperative bleeding. DISCUSSION: Infusion of desmopressin appears to be effective in shortening bleeding time in thrombocytic storage-pool-disease. Its use could prevent bleeding complications after trauma and surgical interventions and may possibly help to spare the need for platelet concentrates.

[Utility of desmopressin in 4 cases of thrombocytopathies associated with giant platelets]. / Utilidad de la desmopresina en cuatro casos de trombocitopatías asociadas a plaquetas gigantes.

Shear-induced aggregation requires the platelet glycoprotein complexes (Gp), the von Willebrand factor (vWf) and ADP. The Bernard Soulier syndrome (BS) and the gray platelet syndrome (GPS) are platelet function defects characterized by absence of GP Ib/IX and alpha granules, respectively, with mucocutaneous hemorrhages, prolonged bleeding time (BT) and moderate thrombocytopenia in both syndromes. There are reports that desmopressin (DDAVP) shortens the BT in some patients with platelet dysfunction. The purpose of this study was to evaluate the response t(DDAVP) in four female patients (2 with GPS plus Marfan's disease and 2 BS). All had bleeding episodes, BTs > 10 minutes, platelet counts (PC) between 40-88 x 10(9)/L and defects in platelet aggregation. The DDAVP was administered at a dose of 0.3 microgram/kg in 15 to 30 mL of isotonic saline given by slow intravenous drip in 30 to 45 min. All patients were studied before and after DDAVP administration (BT, PC, platelet factor, mean platelet volume, factors F.VIII:C, FvW:Ag, FvW:RiC of, and platelet aggregation). After DDAVP infusion the patients had a BT < 6 min, and increased levels of F. VIII:C, FvW:Ag and FvW:RiC of (> 100 Ul/dL), and the bleeding disappeared. We conclude that there was a good response to DDAVP probably associated with improved platelet adhesion, and increases in the multimers of the von Willebrand factor.

[Simultaneous occurrence of lupus anticoagulant and acquired "storage pool" disease of thrombocytes]. / Lupus anticoagulans és szerzett thrombocyta "storage pool" megbetegedés egyidejü elöfordulása.

The authors describe the case of a female patient with a history of simultaneous abortion and deep vein thrombosis as well as moderate bleeding disturbances. Investigations revealed the presence of lupus anticoagulant while a thrombocyte "storage pool" disease was confirmed. This case demonstrates the association of these two haemostatic disturbances, and points to a possible relationship between them. Since detailed analyses failed to demonstrate the presence of antiplatelet antibodies, the authors suggest a possible damaging effect of lupus anticoagulant to the endothelium leading to thrombocyte activation.

Platelet storage pool deficiency, leukemia, and myelodysplastic syndromes.

Abnormalities in platelet dense granules, small intracellular organelles containing ATP, ADP, calcium, serotonin, and pyrophosphate, have frequently been reported in patients with leukemia and myeloproliferative disorders, particularly acute and chronic myelogenous leukemia. Recent studies of a family which includes several members with an autosomal dominant dense granule deficiency condition show an association between the presence of this form of dense granule deficiency and the development of acute myelogenous leukemia. Studies in two additional patients, one with the Monosomy 7 syndrome and the second with a myelodysplastic syndrome, revealed a defect in platelet dense granules. This defect appears to be due to an abnormality in the formation of these granules rather than the presence of empty vesicular structures or decreased contents due to activation associated secretion. The results suggest that the defect in platelet dense granules associated with leukemia or myelodysplastic syndromes may result from a chromosome alteration in the megakaryocyte cell line leading to decreased formation of dense granules. Studies in the family with an inherited bleeding disorder suggest that a gene coding for a protein important for the formation of dense granules is located adjacent to a gene which, when abnormal, may predispose to the development of leukemia.