[Therapy of inherited diseases of platelet function. Interdisciplinary S2K guideline of the Permanent Paediatric Committee of the Society of Thrombosis and Haemostasis Research (GTH e. V.)]. / Therapie hereditärer Thrombozytopathien. Interdisziplinäre S2K-Leitlinie der Ständigen Kommission Pädiatrie der Gesellschaft für Thrombose- und Hämostaseforschung e. V.

Inherited disorders of platelet function are a heterogeneous group. For optimal prevention and management of bleeding, classification and diagnosis of the underlying defect are highly recommended. An interdisciplinary guideline for a diagnostic approach has been published (AWMF # 086-003 S2K; Hämostaseologie 2014; 34: 201-212). Underlying platelet disorder, platelet count, age and clinical situation modify treatment. Exclusive transfusion of platelet concentrates may be inappropriate as potentially adverse effects can outweigh its benefit. A stepwise and individually adjusted approach for restitution and maintenance of haemostasis is recommended. Administration of antifibrinolytics is generally endorsed, but is of particular use in Quebec disease. Restricted to older children, desmopressin is favourable in storage pool disease and unclassified platelet disorders. Although licensed only for patients with Glanzmann thrombasthenia and alloantibodies, in clinical practice rFVIIa is widely used in inherited platelet disorders with severe bleeding tendency. This guideline aims at presenting the best available advice for the management of patients with inherited platelet function disorders.

[Diagnosis of inherited diseases of platelet function. Interdisciplinary S2K guideline of the Permanent Paediatric Committee of the Society of Thrombosis and Haemostasis Research (GTH e. V.)]. / Diagnose angeborener Störungen der Thrombozytenfunktion. Interdisziplinäre S2K-Leitlinie der Ständigen Kommission Pädiatrie der Gesellschaft für Thrombose- und Hämostaseforschung e. V.

Congenital disorders of platelet function are a heterogeneous group of disorders that are often not detected until bleeding occurs. In clinical settings only a few methods have proven to be useful for identification and classification of inherited platelet disorders. For a rational diagnostic approach, a stepwise algorithm is recommended. Patient history and clinical investigation are mandatory. Von Willebrand disease and other coagulation disorders should always be ruled out prior to specific platelet testing. Platelet count, size, volume (MPV) and morphology may guide further investigations. The PFA-100® CT is suited for screening for severe platelet defects. Platelet aggregometry allows assessment of multiple aspects of platelet function. Flow cytometry enables diagnosis of thrombasthenia Glanzmann, Bernard-Soulier syndrome and storage pool defects. Molecular genetics may confirm a putative diagnosis or pave the way for identifying new defects. We present an unabridged version of the interdisciplinary guideline.

Contraception, venous thrombosis and biological plausability.

Exogenous use of hormones leads to different impact on coagulation. Usually estrogen leads to an activation of coagulation, while use of progestogens alone do not. Combined oral contraceptives (COC) differs significantly regarding VTE risk depending on amount of estrogen and type of progestagen: COC containing desogestrol, gestoden or drospirenone in combination with ethinyl-estradiol (EE) (so called 3rd or 4th generation COC) are associated with a higher VTE risk than COC with EE and levonorgestrel or norethisterone (so called 2nd generation COC). The VTE risk for transdermal COC like vaginal ring (NuvaRing) or patch (Evra) is as high than than for COC of 3rd or 4th generation. 2nd generation COC should therefore be the first choice when prescribing hormonal contraception. Most PROGESTAGEN-only contraceptive methods do not increase VTE risk significantly. In patients with a history of venous thromboembolism (VTE) and /or a known thrombophilic defect COC are contraindicated, but progestagen-only contraceptives can be safely used in this patient group. New kinds of COC without EE but with Estradiolvalerat or Estradiol showed a much lower degree of coagulation activation than "classical" COC containing EE. If newer COC with Estradiolvalerat or Estradiol have a lower VTE risk, remains to be elucidated.

[Treatment of haemophilia with an integrated therapeutical concept--Duisburg model]. / Hämophiliebehandlung als ganzheitliches Konzept der Patientenversorgung. Das Duisburger Modell.

A top quality, effective treatment of haemophilia requires an integrated therapeutical concept and an excellent cooperation of an interdisciplinary team. Since years different models are discussed in Germany in order to enlarge the offers for a suitable care of patients with hard to treat diseases. The health-political targets are expressed in the changes of the Code of Social Law number V (SGB V) and in innovations in the statutory health insurance. This new legal basis provides opportunities to implement innovative treatment concepts outside university hospitals and paves the way for ambulant haemophilia centres to offer an integral care, all legally saved by a contract. The Coagulation Centre Rhine-Ruhr reveals as an example how haemophilia treatment in accordance with guidelines and with the latest results of international research can be realise in an ambulatory network.

Hormonal contraception in thrombophilic adolescents: risk of thrombosis and recommendations.

UNLABELLED: About 3.2 million women in Germany are between 14 and 19 years old representing about 19% of women. 55% of them use combined oral contraception (COC). The risk of venous thromboembolism (VTE) during the use of COC is increased 2-6 times. For thrombophilic patients depending on the kind of thrombophilic defect it is much higher. Pregnancy and postpartum period lead to a much higher increase of VTE than any COC use at all, both in women with and without thrombophilic defect. VTE risk in COC is highly dependent on the content of ethinylestradiol (EE) and the kind of progestagen used in COC. Progestagen-only contraceptives (POC) do not increase the VTE risk, since they do not activate the coagulation system. CONCLUSION: It is not justified to withhold any hormonal contraception to thrombophilic women, especially considering the much higher VTE risk in (maybe unintended) pregnancy. Adolescents thrombophilic women should rather be informed about the opportunity to use POC.

Multiplate whole blood impedance point of care aggregometry: preliminary reference values in healthy infants, children and adolescents.

BACKGROUND: The aim of the present study was to evaluate paediatric reference values for platelet function using a point-of-care whole blood impedance aggregometry. METHODS, RESULTS & CONCLUSION: In 265 healthy infants and children aged

Mutations affecting disulphide bonds contribute to a fairly common prevalence of F13B gene defects: results of a genetic study in 14 families with factor XIII B deficiency.

Severe factor XIII (FXIII) deficiency is a rare autosomal recessive coagulation disorder affecting one in two million individuals. The aim of the present study was to screen for and analyse F13B gene defects in the German population. A total of 150 patients presenting with suspected FXIII deficiency and one patient with severe (homozygous) FXIII deficiency were screened for mutations in F13A and F13B genes. Twenty-five individuals presented with detectable heterozygous mutations, 12 of them in the F13A gene and 13 of them in the F13B gene. We report on the genotype-phenotype correlations of the individuals showing defects in the F13B gene. Direct sequencing revealed 12 unique mutations including seven missense mutations (Cys5Arg, Ile81Asn, Leu116Phe, Val217Ile, Cys316Phe, Val401Glu, Pro428Ser), two splice site mutations (IVS2-1G>C, IVS3-1G>C), two insertions (c.1155_1158dupACTT, c.1959insT) and one in-frame deletion (c.471-473delATT). Two of the missense mutations (Cys5Arg, Cys316Phe) eliminated disulphide bonds (Cys5-Cys56, Cys316-Cys358). Another three missense mutations, (Leu116Phe, Val401Glu, Pro428Ser) were located proximal to other cysteine disulphide bonds, therefore indicating that the region in and around these disulphide bonds is prone to functionally relevant mutations in the FXIII-B subunit. The present study reports on a fairly common prevalence of F13B gene defects in the German population. The regions in and around the cysteine disulphide bonds in the FXIII-B protein may be regions prone to frequent mutations.

[Contraception and thrombophilia]. / Kontrazeption bei Thrombophilie.

UNLABELLED: The risk of thromboembolic events (TE) is increased by acquired or inherited thrombophilias (IT). We know that some hormonal contraceptives also increase the risk of thrombosis, thus, the use of such contraceptives are discussed as contraindications in women with IT. TEs are infrequent events in children and adolescents and in the majority of cases are associated with secondary complications from underlying chronic illness. Although adolescents are not typically considered to be at high-risk for TE, this cohort is frequently using hormonal contraception, leading to an increased risk in cases with unknown IT. The risk of TE with pregnancy alone is higher than associated with combined hormonal contraception. Progestin-only methods have not been found to increase the risk of TE with only moderate changes of coagulation proteins compared to normal reference values. CONCLUSION: Thrombophilic women are good candidates for progestin-only contraceptive methods.

Multiple malformations in a male and maternal osteopathia strata with cranial sclerosis (OSCS).

Osteopathia striata with cranial sclerosis (OSCS), conductive hearing impairment and a characteristic facial appearance is the clinical manifestation in carrier women of an X-linked disease. We report on a family with typical OSCS in the mother, a maternal aunt and the grandmother, and multiple severe malformations in the son. He was affected by cranial sclerosis with frontal bossing, conductive hearing impairment, cleft palate, thoracic dysplasia, mesenterium commune with non-rotation of the gut, anal atresia, bilateral cutaneous syndactyly of 3rd and 4th fingers, duplication of the distal phalanx of 2nd and 3rd fingers on the right, bilateral fibular aplasia with clubfeet, developmental retardation, epileptic seizures, hypothyroidism, and hypertrophic pyloric stenosis. The X-inactivation pattern in peripheral leucocytes of one informative carrier woman was random. Our case and several literature reports confirm that males which are hemizygous for the OSCS trait suffer from a dysmorphic syndrome with characteristic multiple malformations as a distinct entity. There is, at present, no reason to assume genetic heterogeneity with an autosomal dominant OSCS variant.

Three novel types of splicing aberrations in the tuberous sclerosis TSC2 gene caused by mutations apart from splice consensus sequences.

Disease causing aberrations in both tuberous sclerosis predisposing genes, TSC1 and TSC2, comprise nearly every type of alteration with a predominance of small truncating mutations distributed over both genes. We performed an RNA based screening of the entire coding regions of both TSC genes applying the protein truncation test (PTT) and identified a high proportion of unusual splicing abnormalities affecting the TSC2 gene. Two cases exhibited different splice acceptor mutations in intron 9 (IVS9-15G-->A and IVS9-3C-->G) both accompanied by exon 10 skipping and simultaneous usage of a cryptic splice acceptor in exon 10. Another splice acceptor mutation (IVS38-18A-->G) destroyed the putative polypyrimidine structure in intron 38 and resulted in simultaneous intron retention and usage of a downstream cryptic splice acceptor in exon 39. Another patient bore a C-->T transition in intron 8 (IVS8+281C-->T) activating a splice donor site and resulting in the inclusion of a newly recognised exon in the mRNA followed by a premature stop. These splice variants deduced from experimental results are additionally supported by RNA secondary structure analysis based on free energy minimisation. Three of the reported splicing anomalies are due to sequence changes remote from exon/intron boundaries, described for the first time in TSC. These findings highlight the significance of investigating intronic changes and their consequences on the mRNA level as disease causing mutations in TSC.

Osteopathia striata with cranial sclerosis: literature reappraisal argues for X-linked inheritance.

Osteopathia striata with cranial sclerosis (OS-CS) is characterized by linear striations of tubular bones and fan-shaped configurations of the ilia. Although referred in literature as an autosomal dominant disorder the clinical pattern of partial involvement as well as the reported family observations plead for X-linked inheritance with mild striated bone affections in carrier women and severe syndromic morbidity and high mortality in the males. Sporadic affected males are probably somatic mosaics. There is no proven father-son transmission. Symptomatic osteopathia striata (OS) is characteristic in X-linked focal dermal hypoplasia Goltz-Gorlin.

Tuberous sclerosis type 1: three novel mutations detected in exon 15 by a combination of HDA and TGGE.

Tuberous sclerosis (TSC) is an autosomal dominant disorder which is genetically heterogeneous with two genes, TSC1 and TSC2. TSC1 consists of 23 exons with exon 15 being the largest one comprising 559 bp. Representing 16% of the coding region exon 15 harbors 37% of the already identified point mutations in TSC1. Mutation screening of large DNA fragments as TSC1 exon 15 by SSCP has been a problem because of the low sensitivity of this method without subdivision. Therefore, we simultaneously performed heteroduplex analysis (HDA) and temperature gradient gel electrophoresis (TGGE) which are both more suitable for evaluation of fragments of this size. DNA samples of 159 patients with the clinical diagnosis of TSC were screened and a total of seven different mutations in nine unrelated cases were identified, including the three novel mutations 1754delT, 1836delT and R500Q. Comparing the two methods applied, HDA showed a higher sensitivity in detecting frameshift mutations, while TGGE seemed to be more sensitive for the detection of base exchanges. We conclude that the combination of these two methods is appropriate to reach a high degree of sensitivity for the detection of all types of small mutations in large DNA fragments.

International recommendations and guidelines for the safe use of diagnostic ultrasound in medicine.

Modern sophisticated ultrasonographic equipment is capable of delivering substantial levels of acoustic energy into the body when used at maximum outputs. The risk of producing bioeffects has been studied by international expert groups during symposia supported by the World Federation for Ultrasound in Medicine and Biology (WFUMB). These have resulted in the publication of internationally accepted conclusions and recommendations. National ultrasound safety committees have published guidelines as well. These recommendations and safety guidelines offer valuable information to help users apply diagnostic ultrasound in a safe and effective manner. Acoustic output from ultrasound medical devices is directly regulated only in the USA and this is done by the Food and Drug Administration (FDA). However, there is also a modern trend towards self-regulation which has implications for the worldwide use of diagnostic ultrasound. It has resulted in a move away from the relatively simple scheme of FDA-enforced, application-specific limits on acoustic output to a scheme whereby risk of adverse effects of ultrasound exposure is assessed from information provided by the equipment in the form of a real-time display of safety indices. Under this option, the FDA allows a relaxation of some intensity limits, specifically approving the use of medical ultrasound devices that can expose the fetus or embryo to nearly eight times the intensity that was previously allowed. The shift of responsibility for risk assessment from a regulatory authority to the user creates an urgent need for awareness of risk and the development of knowledgeable and responsible attitudes to safety issues. To encourage this approach, it is incumbent on authorities, ultrasound societies and expert groups to provide relevant information on biological effects that might result from ultrasonographic procedures. It is obvious from the continued stream of enquiries received by ultrasound societies that effective dissemination of such knowledge requires sustained strenuous effort on the part of ultrasound safety committees. There is a strong need for continuing education to ensure that appropriate risk/benefit assessments are made by users based on an appropriate knowledge of the probability of biological effects occurring with each type of ultrasound procedure. The primary purpose of this paper is to draw attention to current safety guidelines and show the similarities and areas of general agreement with those issued by the parent ultrasound organisation, the WFUMB. It is equally important to identify gaps in our knowledge, where applicable.

Mutation screening of the entire coding regions of the TSC1 and the TSC2 gene with the protein truncation test (PTT) identifies frequent splicing defects.

Mutation analyses in tuberous sclerosis (TSC) have reported a wide variety of disease-causing aberrations in the two known predisposing genes, TSC1 and TSC2 on chromosomes 9q34 and 16p13, comprising mainly small mutations distributed over the entire genes. So far, all known TSC1 mutations as well as the majority of TSC2 mutations truncate the proteins hamartin and tuberin, respectively. We describe for the first time an RNA-based screening of the entire coding regions of both TSC genes for truncating mutations applying the protein truncation test (PTT). Simultaneous investigation of both TSC genes in a group of 48 unassigned TSC patients, which were previously tested to exclude large intragenic TSC2 rearrangements, revealed aberrant migrating polypeptides resulting from truncating mutations in nine TSC1 cases and in 16 TSC2 cases while three TSC2 cases showed enlarged proteins. TSC1 mutations include two nonsense mutations, four insertions, and three splice mutations. Nineteen mutations identified in TSC2 were composed of four different nonsense mutations in five patients, one deletion, one insertion, and seven different splicing aberrations due to at least eight different mutations found in 12 patients. Additional predicted truncating mutations according to PTT without possible identification of the causative alteration allowed assignment to TSC1 in one and TSC2 in seven cases. Twelve patients without abnormalities in the PTT are assumed to harbor missense mutations, probably in TSC2. The high proportion of TSC2 splicing aberrations strengthens the importance of intronic disease-causing mutations and the application of RNA-based screening methods to confirm their consequences.

Extracutaneous analogies of Blaschko lines.

In females, early random X-chromosome inactivation in the late blastocyst and subsequent embryonic development cause a random distribution of cells with an active paternal or maternal X-chromosome. Carriers of X-linked disorders are mostly healthy but, when thoroughly examined, may display a characteristic pattern of partial involvement, which for the skin, is known to follow the lines of Blaschko. Comparable patterns of involvement have been seen in various other organs. The evaluation of carriers who are heterozygous for X-linked disorders, therefore, is an efficient method for the study of functional genetic mosaicism in humans. The same patterns can also be seen in case of early embryonic somatic mutations.