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Haemorrhagic disorders like Postpartum haemorrhage and Dengue haemorrhagic fever are life threatening and requires an active and efficient transfusion service that could provide the most appropriate blood product which could be effective in managing them. This would essentially require prompt identification of the coagulopathy so that the best available product can be given to the bleeding patient to correct the identified haemostatic defect which will help control the bleeding. This would only be possible if the transfusion service has a laboratory to correctly detect the haemostatic defect and that too with an accuracy and precision which is ensured by a good laboratory quality assurance practices. These same processes are necessary for the transfusion services to ensure the quality of the blood products manufactured by them and that it contains adequate amounts of haemostasis factors which will be good to be effective in the management of haemorrhagic disorders. These issues are discussed in detail individually in the management of postpartum haemorrhage and Dengue haemorrhagic fever including when these can help in the use of rFVIIa in Dengue haemorrhagic fever. The requirements to ensure good-quality blood products are made available for the management of these disorders and the same have also been described.

Patients and methods A longitudinal study was carried out in 255 children from 10 centres in nine developing countries over 5 years to assess the musculoskeletal outcome of children on episodic factor replacement. Outcome was documented by assessment of the annual joint bleeding rate (AJBR), WFH clinical and Pettersson radiological joint scores as well as the FISH score for activities. Of the 203 patients for whom data was available at the end of 5 years, 164 who had received only episodic treatment are included in this report. Results The median age at the beginning of the study was 10 years (IQR 7–12). The median clotting factor concentrate (CFC) usage was 662 IU kg−1 year−1 (IQ range: 280–1437). The median AJBR was 10 (IQ range: 5–17). The median AJBR was higher in the older children with the median being 5 for the 5 year old child, while it was 9 for the 10 year old and 11 for children older than 15. Given the episodic nature of the replacement therapy, those with a higher AJBR used significantly greater annual CFC doses (P 3 per year (P = 0.001). The change in the Pettersson score was significantly more in those with an AJBR of >5 per year (P = 0.020). Significant changes in FISH scores were only noted after 10 years of age. Conclusion Episodic CFC replacement over a large range of doses does not alter the natural course of bleeding in haemophilia or the musculoskeletal deterioration and should not be recommended as a long term option for treatment. Prophylaxis is the only way to preserve musculoskeletal function in haemophilia.

Background and objectives Foetal and neonatal alloimmune thrombocytopenia (FNAIT) is studied mainly in Caucasian populations. Severe thrombocytopenia ( 9 /L) gives risk of haemorrhage and the most feared complication is intracranial haemorrhage (ICH). In Caucasian populations anti-human platelet antigen (HPA)-1a antibodies are the cause of FNAIT in >80% of the cases. The aims of this project were to study the gene frequencies of HPA-1-5 and 15 alleles in an Egyptian population (Arabic), and to determine the frequency of HPA-1a and -5b immunisations in a cohort of Egyptian pregnant women. Materials and methods Altogether 6974 pregnant women were included in the study. Genotyping was performed by polymerase chain reaction and antibodies were detected by flow cytometry and enzyme-linked immunosorbent assay. HPA-1-5 and 15 alleles were studied in 367 individuals. Results The HPA genotypes differed from genotypes published from different Caucasian and Chinese (Han) populations in HPA-1, -2, -3, and -5 systems with significant higher frequency of HPA-1b, -2b and -5b. The rate of HPA-1a alloimmunisation was found comparable to Caucasian populations. Severe thrombocytopenia was found in two newborns. No bleeding complication was reported. Anti-HPA-5b antibodies were detected in 4.4% of the pregnant women. Clinical consequences of these antibodies were not studied. Conclusion The HPA-1bb and -5bb genotypes are more frequent in the Egyptian Arabic population studied compared to Caucasian populations. FNAIT due to anti-HPA-1a and -5b antibodies must be suspected in cases of neonatal thrombocytopenia. Further large prospective studies are needed to increase the knowledge of clinical complications related to HPA alloantibodies in populations with different genetic backgrounds.

Summary. Platelets play a pivotal role in the arrest of bleeding at sites of vascular injury. Following endothelial damage, they respond rapidly by adhesion to subendothelial matrix proteins resulting in platelet activation, spreading, aggregation, secretion and recruitment of additional platelets to form the primary haemostatic plug. This mass provides a surface for thrombin generation and fibrin mesh formation that stabilizes the clot. Careful study of patients with inherited platelet disorders and, subsequently, of informative animal models, has identified structural platelet abnormalities that have enhanced our understanding of platelet function. The investigations of rare, but severe, inherited platelet disorders have led us to the discovery of causative molecular defects. One of the most informative is the rare autosomal recessive disorder Glanzmann thrombasthenia, caused by defect or deficiency in the platelet integrin αIIbβ3, resulting in absent platelet aggregation and a significant clinical bleeding diathesis. Our new challenge is to understand the mechanisms underlying more common, but less well-defined, mucocutaneous bleeding (MCB) disorders. Present diagnostic testing for platelet function disorders and von Willebrand’s Disease often fails to identify the cause of bleeding in individuals with inherited MCB.

Eighteen cryoprecipitate minipools, each made of 30 units of low volume, concentrated cryoprecipitate, have been treated by solvent-detergent and filtration (S/D-F) in a single-use CE-marked bag system. The S/D-F cryoprecipitate contained a mean of 10.5 IU mL⁻¹ factor VIII (FVIII), 17 mg mL⁻¹ clottable fibrinogen, and10 IU mL⁻¹ von Willebrand factor ristocetin co-factor, and anti-A and anti-B isoagglutinins were undetectable. The products have been infused in 11 severe (FVIII1%) haemophilia A patients (mean age: 17.4 years; mean weight: 57.6 kg) at a dose close to 40 IU kg⁻¹. Patients were hospitalized for at least 36 h to determine FVIII recovery, half-life and clearance. They were also closely monitored for possible adverse events. None of the infused patients demonstrated reactions or adverse events even though they did not receive anti-allergic drugs or corticosteroids prior to infusion. The mean recovery of FVIII 10 min postinfusion was 69.7%. Mean FVIII half-life was 14.2 h and clearance was 2.6 mL h⁻¹ kg⁻¹. All patients had a bleeding-free interval of 8-10 days postS/D-F cryoprecipitate infusion. The data show that S/D-F cryoprecipitate FVIII presents a normal pharmacokinetics profile, and support that it could be safely used for the control of acute and chronic bleeding episodes in haemophilia A patients.

Platelets play a pivotal role in the arrest of bleeding at sites of vascular injury. Following endothelial damage, they respond rapidly by adhesion to subendothelial matrix proteins resulting in platelet activation, spreading, aggregation, secretion and recruitment of additional platelets to form the primary haemostatic plug. This mass provides a surface for thrombin generation and fibrin mesh formation that stabilizes the clot. Careful study of patients with inherited platelet disorders and, subsequently, of informative animal models, has identified structural platelet abnormalities that have enhanced our understanding of platelet function. The investigations of rare, but severe, inherited platelet disorders have led us to the discovery of causative molecular defects. One of the most informative is the rare autosomal recessive disorder Glanzmann thrombasthenia, caused by defect or deficiency in the platelet integrin alphaIIbbeta3, resulting in absent platelet aggregation and a significant clinical bleeding diathesis. Our new challenge is to understand the mechanisms underlying more common, but less well-defined, mucocutaneous bleeding (MCB) disorders. Present diagnostic testing for platelet function disorders and von Willebrand's Disease often fails to identify the cause of bleeding in individuals with inherited MCB.