The effect of standardised pathway on the diagnosis and management of platelet-related bleeding disorders.

The study will be conducted in two phases: [1] diagnostic phase. Patients with suspected platelet disorders are currently referred to haematologists from the Sydney Platelet Group (SPG) for further diagnostic evaluation after initial medical assessment by whomever referred them. Referred patients will be approached by the investigators for participation in this study. Consenting participants will be assessed by either a face-to-face consultation or on a virtual platform. Participants will have a routine medical history and have a standardised clinical genetic assessment including bleeding score. Blood testing [25mL] will then be performed with samples processed and separated and sent to various laboratories within the SPG network for further biological testing. Much of the diagnostic testing is routine platelet testing and will be processed (ie. collected, tested, reported) as part of routine diagnostic pathology testing. This testing includes full blood and platelet count, blood film, coagulation studies, platelet function testing by aggregation and flow cytometry and electron microscopy. Blood samples intended for research testing (ie. DNA gene panel testing) will be de-identified at collection using a unique patient code. Approximate time for procedures to occur in diagnostic phase Initial approach to patient to send study information. Approx 30mins. Consenting visit, approx 1 wk later to discuss the study with a consultant and undergo blood tests and complete questionnaires. This visit may take up to 2.5hrs. After these tests have been performed, individual patients will be discussed at a multi-disciplinary treatment planning meeting (MDT) involving haematologists, scientists and other individuals with expertise in the diagnosis and management of platelet disorders. The SPG MDT meet 6-8wkly to discuss the diagnostic blood tests, and the outcome of the diagnostic process including whether a definitive diagnosis can be obtained and formulate a patient-specific management plan. The MDT will determine if a specific diagnosis can be identified in the individual or family using well established American College of Medical Genetics and Genomics (ACMG) criteria. If a specific diagnosis is identified by the MDT, a patient-specific management plan will be formulated and this will be provided to the referring doctor and patient participating in the project. The management plan is sent to the referring physician to be implemented by them. A questionnaire to determine if the individualised management plan has been beneficial with respect to reduced bleeding symptomatology and improving quality of life will be sent to the patient one year, or at study close (whichever is sooner). Length of time_approx 15 mths. On the other hand, if the MDT determine a specific diagnosis cannot be determined then the patient will be invited to participate in the second phase of the study, a diagnostic discovery phase. [2] Discovery Phase Individual participants that have not received a definitive diagnosis of their bleeding disorder after a Multi-disciplinary team [MDT] review will be considered for further testing to identify novel causes of bleeding. At this time participants will be contacted by a SPG investigator and informed that their testing to date has not provided a definitive diagnosis. They will then be invited to participate in the second phase of study and provided with the second patient information and consent form outlining the study processes for the Discovery Phase of testing. This form will outline further testing that may be considered to determine a novel cause for the bleeding symptoms. Patients undergoing whole genome sequencing (WGS) will be required to speak with a study haematologist and a genetics expert. Duration of the study is 5 years.