Scott syndrome is a rare congenital bleeding disorder that is due to a defect in a platelet mechanism required for blood coagulation.Normally when a vascular injury occurs, platelets are activated and phosphatidylserine (PS) in the inner leaflet of the platelet membrane is transported to the outer leaflet of the platelet membrane, where it provides a binding site for plasma protein complexes that are  involved in the conversion of prothrombin to thrombin, such as factor VIIIa-IXa (tenase) and factor Va-Xa (prothrombinase).In Scott syndrome, the mechanism for translocating PS to the platelet membrane is defective, resulting in impaired thrombin formation. A similar defect in PS translocation has also been demonstrated in Scott syndrome red blood cells and Epstein–Barr virus transformed lymphocytes, suggesting that the defect in Scott syndrome reflects a mutation in a stem cell that affects multiple hematological lineages.The basis for the defect in PS translocation is, at present, unknown. A candidate protein, scramblase, that may be involved in this process appears to be normal in Scott syndrome platelets. Other possible defects in PS translocation, reported in some patients, require further study. The initially reported patient with Scott Syndrome has been found to have a mutation at a splice-acceptor site of the gene encoding anoctamin 6 (ANO6, transmembrane protein 16F, TMEM16F). At present, the only treatment for episodes of bleeding is the transfusion of normal platelets. References
Further reading
Heemskerk JWM, Bevers EM, Lindhout T. Platelet activation and blood coagulation, Thromb Haem 2002; 88:186–194
Martinez MC, Martin S, Toti F, Fressinaud E, Dachary-Prigent J, Meyer D, et al.
Thioridazine (Mellaril or Melleril) is a first generation antipsychotic drug belonging to the phenothiazine drug group and was previously widely used in the treatment of schizophrenia and psychosis. The branded product was withdrawn worldwide in 2005 because it caused severe cardiac arrhythmias. However, generic versions are still available in the US. Indications
Thioridazine was voluntarily discontinued by its manufacturer, Novartis, worldwide because it caused severe cardiac arrhythmias.Its primary use in medicine was the treatment of schizophrenia. It was also tried with some success as a treatment for various psychiatric symptoms seen in people with dementia, but chronic use of thioridazine and other anti-psychotics in people with dementia is not recommended. Side effects
For further information see: Phenothiazine
Thioridazine prolongs the QTc interval in a dose-dependent manner. It produces significantly less extrapyramidal side effects than most first-generation antipsychotics, likely due to its potent anticholinergic effect. Its use, along with the use of other typical antipsychotics, has been associated with degenerative retinopathies(specifically retinitis pigmentosa). It has a higher propensity for causing anticholinergic side effects coupled with a lower propensity for causing extrapyramidal side effects and sedation than chlorpromazine, but also has a higher incidence of hypotension and cardiotoxicity. It is also known to possess a relatively high liability for causing orthostatic hypotension compared to other antipsychotics. Similarly to other first-generation antipsychotics it has a relatively high liability for causing prolactin elevation. It is moderate risk for causing weight gain.