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Gene therapy (GT) is becoming a realistic treatment option for patients with haemophilia. Outside clinical trials, the complexity and potential complications of GT will pose unprecedented challenges to haemophilia care centres.To explore the potential use of electronic tools to improve the delivery of GT under real-world conditions.Considering the hub-and-spoke model, the GTH working group on GT considered the entire patient pathway and reached consensus on requirements for an integrative software tool to secure documenting and sharing information between treaters, pharmacies and patients.Six steps of the gene therapy process were identified, each requiring completion of the previous step as a prerequisite for entry. The responsibilities of GT dosing and follow-up treatment centres, read/write access rules, and the minimum data set were outlined. Data contributed by patients through mobile devices was also considered.Important information needs to be shared between patients and treatment centres in a real-world GT hub-and-spoke model. Collecting and sharing this information in well-organised electronic applications will not only improve patient care but also enable national and international data collection in clinical registries.

The tyrosine kinase inhibitors (TKIs) imatinib, dasatinib, bosutinib, and nilotinib are established for first-line treatment of chronic myeloid leukemia (CML) but may cause side effects such as bleeding and thrombotic complications. We investigated the impact of TKIs on platelet function ex vivo in anticoagulated whole blood (WB) samples from healthy adults by lumiaggregometry and PFA-100 test. Samples (n = 15 per TKI) were incubated for 30 minutes with TKI at therapeutically relevant final concentrations. Aggregation and ATP release were induced by collagen (1 µg/mL), arachidonic acid (0.5 mmol/L), and thrombin (0.5 U/mL). Imatinib, bosutinib, and nilotinib significantly increased collagen-induced aggregation compared with controls. In addition, for bosutinib and nilotinib, a significant increase in aggregation after induction with arachidonic acid was detected. ATP-release and PFA-100 closure times were not influenced significantly by these three TKI. In contrast, dasatinib demonstrated a concentration-dependent inhibition of collagen-induced aggregation and ATP release and a significant prolongation of the PFA-100 closure time with the collagen/epinephrine cartridge. Aggregation and ATP release by other agonists as well as closure time with the collagen/ADP cartridge were not influenced significantly. In conclusion, we clearly show a concentration-dependent inhibition of collagen-induced platelet function in WB by dasatinib confirming prior results obtained in platelet-rich plasma. Bosutinib and nilotinib exerted no impairment of platelet activation. On the contrary, both TKI showed signs of platelet activation. When comparing our results with existing data, imatinib in therapeutic relevant concentrations does not impair platelet function.

The aim of this review is to provide practical guidance for the treatment of carriers of haemophilia and newborns presenting with haemophilia. Both mother and newborn have an increased risk for clinically relevant bleeding. An experienced team should manage genetic counselling, prenatal diagnosis, pregnancy, delivery and the newborn presenting with haemophilia. Published and regularly updated guidelines must guide this team. Vaginal and caesarean deliveries before labour entail a comparable bleeding risk. Haemophilia carriers should receive factor concentrate (FC) at the time of delivery if their factor level is below normal. Evidence remains insufficient to recommend systemic desmopressin and tranexamic acid for the prevention of peripartum haemorrhage. Primary prophylaxis with FC for all newborns with severe haemophilia is not justified. The pattern of bleeding seen in the affected newborns is essentially different from that seen in older children. Estimated frequency of intracranial haemorrhage (ICH) is 2 to 3%. Cranial ultrasound is a good screening method for ICH in newborns. Many neonatal bleeds are iatrogenic in origin. The most prominent concerns regarding neonatal factor replacement are the risk for inhibitor development, followed by local bleeding and issues related to poor vascular access. The preference for plasma-derived FC and recombinant FC differs widely between centres and countries. Replacement therapy should be monitored since newborns may require higher doses of FC. Emicizumab, licensed for all age groups since 2019, should not be used in newborns with severe haemophilia A and acute bleeding, although "non-factor" agents are expected to revolutionise haemophilia therapy.Ziel dieser Übersicht ist eine praktische Anleitung zum Umgang mit Überträgerinnen von Hämophilie (Konduktorinnen) und Neugeborenen mit Hämophilie zu geben. Sowohl Konduktorinnen als auch betroffene Nachkommen haben ein relevant erhöhtes Blutungsrisiko. Nur ein erfahrenes Team sollte genetische Beratung, Pränatal diagnostik, Schwangerschaft, Geburt und das betroffene Neugeborene betreuen. Publizierte und regelmäßig aktualisierte Leit- und Richtlinien müssen immer die Grundlage des Handelns sein. Die vaginale Entbindung und der elektive Kaiserschnitt haben ein vergleichbares Blutungsrisiko. Für Konduktorinnen, die bei der Geburt einen Faktorspiegel unter dem Normalwert aufweisen, sind Faktorkonzentrate empfohlen. Die Wirksamkeit von Desmopressin und Tranexamsäure zur Behandlung peri- und postpartaler Blutungen ist nicht gesichert. Eine primäre Prophylaxe mit Faktorkonzentraten aller Neugeborenen mit schwerer Hämophilie ist nicht gerechtfertigt. Blutungen des Neugeborenen unterscheiden sich grundsätzlich von denen des älteren Kindes. In 2 bis 3% treten intrakranielle Blutungen auf. Die Ultraschalluntersuchung ist eine gute Suchmethode zum Ausschluss einer intrakraniellen Blutung beim Neugeborenen. Viele Blutungen werden erst durch medizinische Manipulationen verursacht. Die größten Bedenken gegen eine frühe Behandlung mit Faktorenkonzentraten von hämophilen Neugeborenen sind die Entwicklung eines Hemmkörpers gegen FVIII/ IX, lokale Blutungskomplikationen und der problematische venöse Zugang. Unterschiedlich nach Land und Zentrum werden bevorzugt aus Plasma hergestellte oder rekombinante Faktorkonzentrate verabreicht. Bei jeder Faktorgabe sollte der Faktorspiegel überwacht werden, da Neugeborene mehr Faktor benötigen können als ältere Kinder. Zurzeit wird von der Verwendung von Emicizumab, das seit 2019 für alle Altersgruppen zugelassen ist, für Neugeborene mit schwerer Hämophilie A und akuter Blutung abgeraten, auch wenn zu erwarten ist, dass “non-factor” Medikamente die Behandlung der Hämophilie revolutionieren werden.

We report about a female toddler congenitally deaf and diagnosed with a non-metastatic desmoplastic medulloblastoma (SHH activated, TP53-wt, variant in LDB1 gene). No tumor predisposition syndrome was found. After complete tumor resection the patient was treated according to I-HIT-MED-Guidance protocol. Five months later an asymptomatic localised relapse (same histology, PTEN frameshift deletion, TERT mutation, LDB1 mutation) detected by routine MRI was treated by complete resection, craniospinal irradiation and an antiangiogenic regimen adapted from the MEMMAT scheme including fenofibrate, thalidomide, celecoxib, topotecan, temozolomide, bevacizumab and intraventricular cytarabine. Before start of systemic treatment blood cell counts were normal. In the second cycle we had to interrupt chemotherapy due to a leukopenia while continuing the antiangiogenic treatment. In order to avoid relevant bone marrow toxicity chemotherapy doses were reduced. Nevertheless we had to stop the fourth cycle because of a severe pancytopenia. Same time the girl presented with fever, neck and leg pain. A full blood count showed: hemoglobin 6.92 g/dl, leukocytes 640/µl, platelets 8,000/µl. Suspecting an infection supported by the presence of a high CrP value of 230 mg/l the patient was treated with i.v. antibiotics. MRI showed an unspecific retropharyngeal soft tissue augmentation, a pleural effusion and high T2 signals in multiple vertebral bodies but no central tumor relapse. The bone marrow diagnostics revealed a diffuse medulloblastoma cell infiltration with the known PTEN frameshift deletion and LDB1 mutation. The liquor was tumor-cell free. We report on an extremely rare case of an early local relapse of desmoplastic medulloblastoma progressing to a diffuse bone marrow infiltration in a toddler. The girl died due to therapy resistance 9 weeks after bone marrow relapse. It remains unclear whether the fatal course was related to the hereditary deafness syndrome and the molecular alterations of the tumor.

Introduction Light transmission aggregometry (LTA) is regarded as the gold standard in platelet function diagnostics. However, there is a relevant degree of interlaboratory variability in practical applications. Objective The aim of the present study was to develop a practicable laboratory comparison on LTA and to analyze differences and influencing factors in regard to standardization in five specialized hemostaseological centers. Methods The study was performed on 30 patients in total. Each center performed LTA on blood samples from six healthy volunteers (three men and three women) using the inductors collagen (Col), adenosine diphosphate (ADP), arachidonic acid (ARA), and ristocetin. The LTA was performed three times using different methods as follows: (1) International Society on Thrombosis and Haemostasis recommendations with identical reagents, (2) in-house protocols and the identical reagents; and (3) in-house protocols and in-house reagents. Results A total of 396 measurements of 30 probands were performed. Even after standardization of the protocol and using identical reagents, there were significant differences between the centers regarding the final and maximum aggregation (p = 0.002 and Conclusion In this study, we proved that there are significant influences from the used aggregometers, inductors concentrations, and manufacturers. These results illustrate the challenges and importance of standardization of LTA.

Background Isolated myelosarcoma of infancy is a rare presentation of acute myelogenous leukaemia (AML). Because of its rarity and early onset in infancy underlying genetic predisposition is potentially relevant in disease initiation. Methods and Results We report an oncologic emergency in an infant with thoracic and intraspinal aleukaemic myeloid sarcoma causing acute myelon compression and lower leg palsy. Whole‐exome sequencing of the patient's germline DNA identified a rare PALB2 (OMIM 610355) variant (p.A1079S), which is located in a domain critical for the gene's proper function within the homology‐directed repair pathway. In line with potential DNA damage repair defects mediated by the PALB2 deregulation, the patient's fibroblasts showed increased sensitivity towards radiation and DNA intercalating agents. Conclusion Therefore, we suggest PALB2 p.A1079S as a pathogenic variant potentially contributing to the here observed patient phenotype., We present the finding of an infant with thoracic and intraspinal aleukemic myeloid sarcoma with a rare germline PALB2 variant (p.A1079S). The identified variant is located in a domain critical for the gene's proper function within the homology‐directed repair pathway. A functional role of the variant is further supported by increased sensitivity towards irradiation and DNA intercalating agents observed in primary cells from the patient carrying PALB2 p.A1079S.

Germline mutations in the ubiquitously expressed ACTB, which encodes β-cytoplasmic actin (CYA), are almost exclusively associated with Baraitser-Winter Cerebrofrontofacial syndrome (BWCFF). Here, we report six patients with previously undescribed heterozygous variants clustered in the 3′-coding region of ACTB. Patients present with clinical features distinct from BWCFF, including mild developmental disability, microcephaly, and thrombocytopenia with platelet anisotropy. Using patient-derived fibroblasts, we demonstrate cohort specific changes to β-CYA filament populations, which include the enhanced recruitment of thrombocytopenia-associated actin binding proteins (ABPs). These perturbed interactions are supported by in silico modeling and are validated in disease-relevant thrombocytes. Co-examination of actin and microtubule cytoskeleton constituents in patient-derived megakaryocytes and thrombocytes indicates that these β-CYA mutations inhibit the final stages of platelet maturation by compromising microtubule organization. Our results define an ACTB-associated clinical syndrome with a distinct genotype-phenotype correlation and delineate molecular mechanisms underlying thrombocytopenia in this patient cohort. Genetic variants in ACTB and ACTG1 have been associated with Baraitser-Winter Cerebrofrontofacial syndrome. Here, the authors report of a syndromic thrombocytopenia caused by variants in ACTB exons 5 or 6 that compromise the organization and coupling of the cytoskeleton, leading to impaired platelet maturation.

Epidemiologie Storungen der prim€aren H€amostase sind die h€aufigste Ursache einer Blutungsneigung im Kindesund Erwachsenenalter. Bei den heredit€aren Storungen steht das Von-Willebrand-Syndrom (VWS) an erster Stelle. Die h€aufigsten Ursachen insgesamt sind die erworbenen Thrombozytopenien und Thrombozytenfunktionsstorungen; die angeborenen Thrombozytopenien und Thrombozytenfunktionsstorungen sind wesentlich seltener. Die Vasopathien z€ahlen zu den Rarit€aten.

An den Aufgaben der Hamostase, die Fliesfahigkeit des Bluts optimal zu erhalten und gleichzeitig Blutverluste nach Verletzungen zu verhindern, sind im Wesentlichen 3 Systeme beteiligt: das Gefassystem selbst, die Blutplattchen und die plasmatische Gerinnung.

In 2005 the Kompetenznetz Hämorrhagische Diathese Ost published epidemiologic data about patients with haemophilia A (HA) and haemophilia B (HB) in the eastern part of Germany. This study provides data about the development of treatment in these patients over the past 10 years. Data from 12 haemophilia centres in eastern Germany were retrospectively collected for the year 2015 from patients' records. We evaluated 413 patients (115 children, 298 adults) with HA or HB. A total of 286 patients (69.2%) had severe haemophilia (patients with severe haemophilia, PWSH). Compared with 2005, the proportion PWSH on prophylaxis increased from 90% to 98.8% in children and from 64% to 80.2% in adults. The use of plasma-derived factor concentrates decreased from70% to 55.3% in children and to 55.1% in adults. Mean annual factor consumption in PWSH without inhibitor was higher in 2015 compared with 2005 (children with HA: 151,489 vs. 98,894; adults with HA: 217,151 vs. 151,394; children with HB: 105,200 vs. 64,256; adults with HB: 159,185 vs. 85,295). Median annualized bleeding (annualized bleeding rate, ABR) and joint bleeding rates (annualized joint bleeding rate, AJBR) in 2015 were 2 and 0 in children and 3 and 0 in adults, respectively. In 2015 only one child (1.2%) but 101 (53.2%) adults with severe haemophilia were anti-hepatitis C virus (anti-HCV) positive. The rate of anti-HCV positive patients with active hepatitis C dropped from 63.8% to 12.9%. Within the last decade more patients with severe haemophilia were switched to a prophylactic regimen going along with a moderate increase in factor consumption achieving a low ABR and AJBR. Im Jahr 2005 hat das Kompetenznetz Hämorrhagische Diathese Ost epidemiologische Daten über Patienten im Osten Deutschlands mit Hämophilie A (HA) und B (HB) publiziert. Diese Studie liefert Daten über die Entwicklung der Hämophiliebehandlung bei diesen Patienten in den letzten 10 Jahren. Daten von 12 Hämophiliezentren im Osten Deutschlands aus dem Jahr 2015 wurden retrospektiv aus den Patientenakten ausgewertet. Wir untersuchten 413 Patienten (115 Kinder, 298 Erwachsene) mit HA oder HB. 286 Patienten (69,2%) hatten eine schwere Hämophilie (PMSH). Im Vergleich zu 2005 ist der Anteil der PMSH mit Prophylaxe bei den Kindern von 90% auf 98.8% und bei den Erwachsenen von 64% auf 80,2% angestiegen. Der Verbrauch von plasmatischen Faktorenkonzentraten ist von70% auf 55,3% bei Kindern und 55,1% bei Erwachsenen gesunken. Der mittlere Faktorenverbrauch bei PMSH ohne Hemmkörper war 2015 höher als 2005 (Kinder mit HA 151.489 versus 98.894, Erwachsene mit HA 217.151 versus 151.394, Kinder mit HB 105.200 versus 64.256, Erwachsenen mit HB 159.185 versus 85.295). Die mediane jährliche Blutungsrate und Gelenkblutungsrate in 2015 war 2 bzw. 0 bei Kindern und 3 bzw. 0 bei Erwachsenen. Im Jahr 2015 war lediglich ein Kind (1,2%) aber 101 (53,2%) Erwachsene mit schwerer Hämophilie anti-HCV positiv. Der Anteil der anti-HCV-positiven Erwachsenen mit aktiver Hepatitis C fiel von 63,8% auf 12,9%. In den letzten 10 Jahren wurden mehr Patienten auf eine prophylaktische Behandlung umgestellt. Dies geht mit einem moderaten Anstieg des Verbrauchs an Faktorenkonzentraten einher, resultiert aber in einer niedrigen Blutungsrate.

Chronic hemorrhagic diathesis in patients showing normal levels of plasmatic clotting factors strongly suggests for congenital platelet disorders. We report on a pediatric patient (male, 3 years, D1) with mild bleeding. A sibling (D2), his mother (D3) and father (D4) were included for laboratory investigation. Platelet counts in D1, D2 and D4 indicated mild thrombocytopenia (100 Gpt/L). D1 and D3 platelets showed significantly diminished aggregation response on arachidonic acid and U46619 stimulation. Immunostaining for platelet proteins on blood smears of D1 and D2 indicated defects in ß1-tubulin. Exon sequencing of

A considerable proportion of patients with chronic myeloid leukaemia (CML) may present at diagnosis with high platelet counts. This may result in thrombosis or bleeding complications due to binding of von Willebrand factor (VWF) multimers to platelets. Paediatric CML is very rare and no systematic investigation on clinical complications of elevated platelets has been reported. Data on platelet count and associated haemostaseological complications were retrospectively analysed in a cohort of 156 children with CML. Fifty-one percent (81/156) patients presented with thrombocytosis (platelet count> 500 × 109 /l), and were extreme (>1 000 × 109 /l) in 23/156 (16%). There were no cases of thrombosis but mild bleeding signs were present in 12% (n = 9) children with thrombocytosis. Bleeding occurred without correlation to elevated platelet counts and was associated with reduced large VWF multimers, indicating a diagnosis of acquired von Willebrand syndrome (AVWS), which resolved after initiation of CML treatment. Patients with paediatric CML frequently exhibit high platelet counts not resulting in thrombosis. In patients with thrombocytosis mild bleeding signs due to a low percentage of large VWF multimers can be demonstrated. AVWS may be underdiagnosed in paediatric CML (Clinical-Trials.gov NCT00445822, 9 March 2007).

Similar to the general population, overweight and obesity have increasingly become a medical and economic burden also in patients with haemophilia in industrialized nations. In this study in seven German haemophilia centres, we identified a prevalence of overweight and obesity of 25.2% among 254 young patients

Antineoplastic treatment of osteoblastic osteosarcoma in a patient with cystic fibrosis (CF) may harbor a high risk of neutropenia-associated complications, and, to the best of our knowledge, has not been previously reported. Diagnosis of CF was confirmed in a 6-week-old boy following pathological newborn screening. The patient had a stable course of CF under standardized continuous therapy. At the age of 5 years, osteosarcoma of the left proximal humerus was diagnosed without evidence of metastases. Neoadjuvant chemotherapy, including doxorubicin, cisplatin and methotrexate, was administered for 10 weeks. The patient tolerated this therapy relatively well, with a continuous antibiotic prophylaxis of cefuroxime without experiencing major complications; in particular, no pulmonary exacerbations were observed as a consequence of immunosuppression or mucosal toxicity. The tumor responded well, and amputation of the limb was avoided via the use of 'clavicle per humerus' osteosynthesis. Postoperatively, compartmental syndrome occurred, requiring management by fasciotomy. Adjuvant chemotherapy was applied thereafter again, without major toxicity that would have required dose reduction. Under intensive physiotherapy, the mobility of the left arm and hand was deemed to be satisfactory. The coincidence of CF with osteosarcoma is extremely rare, and, to the best of our knowledge, has not been previously described. Under antibiotic prophylaxis, antineoplastic treatment was possible without major complications during neutropenia.

Children with an unexplained bleeding tendency are frequently referred to a haemostaseologist for further evaluation. Careful standardized history taking and clinical evaluation should allow for distinguishing bleeds after minor injury and trauma which are very common in all children. However, in two groups of children bleeding symptoms may be more significant than expected: those with an underlying coagulation disorder and those who have been subjected to physical child abuse. The coexistence of child abuse and a bleeding disorder must always be considered. An extended coagulation diagnostic is required if the morphology of bleedings is not clearly suspicious for child abuse and in the absence of typical concomitant injuries, e.g., bone fractures. An interdisciplinary approach involving a forensic pathologist and a paediatric haemostaseologist for assessment of bleeding symptoms, the explanation of the clinical findings, and the critical evaluation of laboratory results are essential in such cases. This review is focussed on symptoms in accidental and nonaccidental injuries in children assisting haemostaseologists in decision making in cases of child protection issues.Kinder mit unklarer Blutungsneigung werden häufig zum Hämostaseologen zur Abklärung geschickt. Eine standardisierte Ananmneseerhebung und klinische Untersuchung erlauben es zu entscheiden, ob es sich um Blutungen durch kleine Verletzungen und Traumata handelt. In der Regel treten bei 2 Gruppen von Kindern relevante Blutungen auf: Kinder mit Gerinnungsstörung und solche, die körperlich misshandelt werden. Dabei ist stets zu berücksichtigen, dass auch gleichzeitig eine Gerinnungsstörung und eine Misshandlung vorliegen kann. Eine erweiterte Gerinnungsdiagnostik ist erforderlich, wenn die Blutungsmorphe nicht eindeutig für eine Misshandlung spricht und beim Fehlen typischer Begleitverletzungen, wie Frakturen. In diesen Fällen ist ein interdisziplinäres Vorgehen unter Einbeziehung eines Rechtsmediziners und eines pädiatrischen Hämostaseologen zur Beurteilung der Symptome, den Erklärungen für das vorliegende klinische Bild und eine kritische Bewertung der Befunde der Gerinnungsdiagnostik notwendig. Diese Übersichtsarbeit fokussiert auf Symptome bei akzidentellen und nicht-akzidentellen Verletzungen und soll eine Entscheidungshilfe für Hämostaseologen in Kinderschutzfällen darstellen.

Burkitt lymphoma (BL) in children often presents with abdominal localization. Intestinal perforations have been described mainly during treatment. We report on a three-year-old patient with abdominal BL who was diagnosed with a duodenocolonic fistula.A three-year-old boy presented with diarrhea, crampy abdominal pain, and a four-week history of loss of appetite and weight. Ultrasound and MRI detected a colonic tumor forming a duodenocolonic fistula which was verified by gastroduodenoscopy. A surgical biopsy revealed BL. The stage III BL with low LDH was treated with four courses of BFM-type short-pulse chemotherapy. After two courses of chemotherapy the patient developed a mechanic ileus. A segmental resection of a short segment of the colon at the right flexure carrying the residual tumor mass with cicatricial stenosis and fistula followed by colonic end to end anastomosis and covering of the fistula by omentum major were carried out without complication. 15 days after surgery, two additional courses of chemotherapy could be administrated and the boy is in ongoing remission and free of any symptoms with a follow-up interval of 18 months.Duodeonocolonic fistula at presentation in a child with abdominal BL is extremely rare. Delayed surgery after size of the tumor bulk has been reduced by chemotherapy might represent a risk adapted approach. However, due to limited experience with duodenocolonic fistulas even in larger pediatric lymphoma trials any decision has to be based on the problems to be faced in individual cases.Ein Burkitt-Lymphom (BL) im Kindesalter ist oft im Abdomen lokalisiert. Intestinale Perforationen wurden in der Literatur zumeist als während der Chemotherapie auftretende Komplikation beschrieben. Wir berichten über einen Patienten mit abdominellen BL, welcher bei Diagnosestellung eine duodenokolische Fistel aufwies.Ein 3jähriger Junge wurde vorgestellt mit rezidivierenden Diarrhoen, krampfartigen Bauchschmerzen, Appetitlosigkeit und Gewichtsverlust über einen 4wöchigen Zeitraum. Die radiologische Diagnostik mittels Abdomensonographie und MRT ergab das Bild eines Tumors, welcher eine duodenokolonische Fistel ausgebildet hatte, was mittels Ösophagogastroduodenoskopie bestätigt wurde. Die chirurgische Tumorbiopsie sicherte den Befund eines BL. Es handelte sich um das Stadium III mit einer leichten LDH-Erhöhung. Nach 2 Blöcken der Chemotherapie entwickelte der Patient einen mechanischen Ileus. Eine operative kurzstreckige Segementresektion des stenosierenden und fistelbildenden Tumors im Bereich des Colons ascendens wurde mit einer End-zu-End-Anastomose und Abdecken der Fistel durch Omentum majum ohne Komplikationen durchgeführt. Am 15. postoperativen Tag konnten anschließend 2 weitere Chemotherapie-Blöcke verabreicht werden. Der Patient befindet sich 16 Monaten später beschwerdefrei in Remission.Eine duodenokolonische Fistel als Komplikation eines abdominellen BL ist eine extreme Rarität. Die verzögerte Resektion nach Tumorverkleinerung durch Chemotherapie stellt möglicherweise eine risiko-adaptierte Vorgehensweise dar. Jedoch sollte jede Entscheidung zur Vorgehensweise bei duodenokolonischen Fisteln aufgrund der fehlenden Erfahrungen im Kindesalter auch innerhalb großer Lymphomstudien immer individuell angepasst sein.

SummaryVenous thromboembolism [TE] is a multifactorial disease, and protein S deficiency [PSD] constitutes a major risk factor. In the present study the prevalence of PSD and the clinical presentation at TE onset in a cohort of children is reported. In 367 unselected paediatric patients with TE (age 0.1–18 years) recruited between July 1996 and December 2013, a comprehensive thrombophilia screening was performed along with recording of anamnestic data. Thirty of 367 paediatric patients (8.2 %) derived from 27 families had PSD. Mean age at first TE onset was 14.5 years (range 0.1 to 18). Thrombotic locations were cerebral veins (n=8), calf vein TE (n=3) deep veins (DVT) of the leg (n=12), DVT & pulmonary embolism (n=5) and intra-cardiac veins (n=1) or purpura fulminans (n=1). PSD co-occurred with the factor 5 mutation at rs6025 or the homozygous factor 2 susceptibility variant at rs1799963 in one case each. The Heerlen polymorphism detected in five children presented with milder PSD. In 18 patients (60 %) a concomitant risk factor for TE was identified. A second TE event within primarily healthy siblings occurred in three of 27 PSD families (11.0 %). In this cohort of children with symptomatic TE, the prevalence of PSD adjusted for family status was 7.4 %. Given its clinical implication for patients and family members, thrombophilia testing should be performed and the benefit of medical or educational interventions should be evaluated in this high-risk population.

SummaryCongenital thrombocytopenia in childhood and adolescence requires an extensive diagnostic workup to find the underlying reason. We report on a 13-year-old female patient who was incidentally found to have moderate thrombocytopenia which was also diagnosed in her father and brother. Within the microscopic evaluation of a peripheral blood smear macrothrombocytes were found. Immunofluorescence microscopy of the patient’s platelets detected the lack of D1-tubulin. Analysis of the TUBB1 gene revealed three known missense variants in heterozygous state which in combination might explain the D1-tubulin defect.

ZusammenfassungAngeborene Thrombozytopathien sind komplexe Erkrankungen. Zur optimalen Blutungsprophylaxe und -behandlung empfehlen wir eine Abklärung und Diagnose der zugrunde liegenden Funktionsstörung. Dazu steht eine interdisziplinäre Leitlinie zur Verfügung (AWMF # 86–003 S2K; Hämostaseologie 2014; 34: 201–212).Die Behandlung ist auf den Defekt, die Thrombozytenzahl, das Lebensalter und die klinischen Umstände abzustimmen. Die Transfusion von Thrombozyten allein kann wegen der damit verbundenen Risiken unangemessen sein. Empfohlen wird ein stufenweiser und individualisierter Behandlungsplan. Antifibrinolytika sind generell anwendbar, besonders bei der Quebec-Erkrankung. Desmopressin ist älteren Kindern vor behalten und vor allem zur Behandlung der Storage- Pool-Erkrankungen und nicht klassifizierter Defekte geeignet. Rekombinanter FVIIa ist zwar nur für die Behandlung der Thrombasthenie Glanzmann mit Alloantikörpern zugelassen, wird jedoch in der klinischen Praxis auch bei Thrombozytendefekten mit schwerer Blutungsneigung eingesetzt. Das Ziel dieser Leitlinie ist die Behandlung von Patienten mit angeborenen Thrombozytenfunktionsstörungen bestmöglich zu unterstützen.

SummarySummary: The manifestation of an unclear bleeding tendency in childhood calls for an extended coagulation work-up, particularly when a battered child syndrome is suspected and typical concomitant injuries are absent. The chosen diagnostic tests should be able to detect the presence of relatively common coagulation defects such as von Willebrand syndrome or hemophilia, but also rare diseases such as inherited thrombocytopathies. The PFA-100® test does not help to provide a definite diagnosis especially in cases of mild inherited thrombocytopathies, since in most cases the PFA-100® test results are normal. For this purpose, specific platelet function testing is needed. However, the methods are only available in some coagulation laboratories. Also, other limitations need to be taken into consideration such as pre-analytical problems and difficulties in the interpretation of test results especially in infants.We present two cases that were diagnosed with an aspirin-like defect as an inherited thrombocytopathy, even though their PFA-100 closure times were within the normal range. Based on pathological findings in the platelet aggregometry test, this diagnosis could be made.

SummaryIntroduction: Desmopressin (DDAVP) testing (DT) in patients (pts) with haemophilia A (HA) and carriers (CHA) is up to now not standardized. This prompted us to evaluate results of DT carried out between 1996 and 2011 in centres of the Competence Network Haemor-rhagic Diatheses East. Patients and method: An increase of the factor VIII activity (FVIII) above 50% or at least the two fold of initial values within 120 min after DDAVP was defined as complete response (CR). Data from 80 patients (31 children, 49 adults) of whom 64 suffered from HA (sub-HA: n = 48; mild: n = 14; moderate: n = 2) and 16 patients CHA were evaluated. Results: In 34 patients DDAVP was given i. v. (dose range: 0.26–0.6 μg/kg body weight, mean: 0.33), in 31 intranasally (i.n. 300–600 μg) and in 15 s. c. (15–40 μg). The maximal FVIII increase was reached 60 min after DDAVP. For i. v. application the mean FVIII increase was 3.1-fold, for i. n. 2.1-fold and for s. c. 2.4-fold. A CR was de tected in 71 patients, a non-response in 9. Mild side effects such as flush, headaches or nausea were observed in 11 patients (14%). Conclusion: For desmopressin testing in patients with haemophilia A and carriers i. v. application at 0.3 μg/kg body weight and the determination of FVIII before and 60 min after desmopressin infusion is recommended.

Hereditary disorders of platelet function are a heterogeneous group of diseases that are often complex and tend to go undetected until clinically relevant bleeding occurs. Hallmarks are epistaxis, easy bruising, mucous membrane bleeding, perioperative bleeding and menorrhagia. Bleeding may be intermittent and unpredictable. After decades of successful research on platelet biology and genetics, research findings have not been satisfactorily translated to clinical practice. The lack of robust and well- standardized test systems continues to make the diagnosis of platelet defects cumbersome for the practising clinician. Patient history and description of clinical bleeding symptoms are essential. Exclusion of von Willebrand disease, platelet count and investigation of blood smears may provide a tentative diagnosis. Light transmission aggregometry is still considered the gold standard for assessing platelet function. Due to the wide range of possible genetic defects molecular biological analyses can complement but do not substitute for other tests. The true incidence of inherited disorders of platelet function is unknown. A survey in Germany revealed that receptor-defects including Glanzmann's thrombasthenia and Bernard-Soulier syndrome and aspirin-like defects were the most frequently diagnosed platelet disorders. Of affected children 60% presented with mild and 40% with moderate to severe bleeding tendency. Epistaxis, cutaneous and mucous membrane bleeding were the most frequent symptoms. The paediatric competence network of the GTH e.V. comprises 44 collaborating centres that are caregivers to over 150 children with well-defined inherited platelet defects. A major goal of this network is to promote diagnosis of children with inherited disorders of platelet function.

Background: Assessment of platelet vitality is important for patients presenting with inherited or acquired disorders of platelet function and for quality assessment of platelet concentrates. Methods: Herein we combined live stains with intra-vital confocal fluorescence microscopy in order to obtain an imaging method that allows fast and accurate assessment of platelet vitality. Three fluorescent dyes, FITC-coupled wheat germ agglutinin (WGA), tetramethylrhodamine methyl ester perchlorate (TMRM) and acetoxymethylester (Rhod-2), were used to assess platelet morphology, mitochondrial activity and intra-platelet calcium levels. Microscopy was performed with a microlens-enhanced Nipkow spinning disk-based system allowing live confocal imaging. Results: Comparison of ten samples of donor platelets collected before apheresis and platelets collected on days 5 and 7 of storage showed an increase in the percentage of Rhod-2positive platelets from 3.6 to 47 and finally to 71%. Mitochondrial potential was demonstrated in 95.4% of donor platelets and in 92.5% of platelets stored for 7 days. Conclusion: Such fast and accurate visualization of known key parameters of platelet function could be of relevance for studies addressing the quality of platelets after storage and additional manipulation, such as pathogen inactivation, as well as for the analysis of inherited platelet function disorders. Hintergrund: Die Vitalitätsbestimmung von Blutplättchen ist sowohl für die Analyse angeborener Plättchendefekte als auch für die Qualitätsbestimmung von Plättchenkonzentraten von zentraler Bedeutung. Methoden: In der vorliegenden Arbeit stellen wir eine Methode vor, die mittels einer Kombination von Vitalfarbstoffen und konfokaler «Real time»-Mikroskopie neue Einblicke in die Vitalitätsbestimmung lebender Plättchen ermöglicht. Mittels der Zugabe von FITC-gekoppeltem Weizenkeimlektin (WGA), Tetramethylrhodamin-Methylesterperchlorat (TMRM) und Acetoxymethylester (Rhod-2) wurde bei lebenden Blutplättchen deren Morphologie, mitochondriale Aktivität und Veränderungen im Calcium-Haushalt im Rahmen der Lagerung analysiert. Für die Mikroskopie wurde ein Nipkow-System gewählt, das eine konfokale Mikroskopie lebender Zellen ermöglicht. Ergebnisse: Der Vergleich von 10 humanen Blutplättchenproben zu Beginn bzw. nach 5 und 7 Tagen Lagerung zeigte einen Anstieg der Rhod-2-positiven Plättchen von 3,6 über 47 auf 71%. Die Anzahl der Blutplättchen mit TMRM-positiven Mitochondrien hingegen lag vor der Lagerung bei 95,4% und nach den 7 Tagen Lagerung bei 92,5%. Schlussfolgerung: Die hier vorgestellte Methodik der Bildgebung zur Bestimmung vitaler Parameter von Blutplättchen eignet sich als ergänzende Analysemodalität für eine bessere Bestimmung der Blutplättchenqualität. Dieser Beitrag ist mit Zustimmung des Rechteinhabers aufgrund einer (DFG-geförderten) Allianz- bzw. Nationallizenz frei zugänglich.