The accuracy of a patient or parent-administered bleeding assessment tool administered in a paediatric haematology clinic.

Classifying and describing bleeding symptoms is essential in the diagnosis and management of patients with mild bleeding disorders (MBDs). There has been increased interest in the use of bleeding assessment tools (BATs) to more objectively quantify the presence and severity of bleeding symptoms. To date, the administration of BATs has been performed almost exclusively by clinicians; the accuracy of a parent-proxy BAT has not been studied. Our objective was to determine the accuracy of a parent-administered BAT by measuring the level of agreement between parent and clinician responses to the Condensed MCMDM-1VWD Bleeding Questionnaire. Our cross-sectional study included children 0-21 years presenting to a haematology clinic for initial evaluation of a suspected MBD or follow-up evaluation of a previously diagnosed MBD. The parent/caregiver completed a modified version of the BAT; the clinician separately completed the BAT through interview. The mean parent-report bleeding score (BS) was 6.09 (range: -2 to 25); the mean clinician report BS was 4.54 (range: -1 to 17). The mean percentage of agreement across all bleeding symptoms was 78% (mean κ = 0.40; Gwet's AC1 = 0.74). Eighty percent of the population had an abnormal BS (defined as ≥2) when rated by parents and 76% had an abnormal score when rated by clinicians (86% agreement, κ = 0.59, Gwet's AC1 = 0.79). While parents tended to over-report bleeding as compared to clinicians, overall, BSs were similar between groups. These results lend support for further study of a modified proxy-report BAT as a clinical and research tool.

Menstrual bleeding patterns and prevalence of bleeding disorders in a multidisciplinary adolescent haematology clinic.

Heavy menstrual bleeding (HMB) is a frequent complaint in adolescence. Although HMB is often caused by immaturity of the hypothalamic-pituitary-ovarian axis, bleeding disorders are another common yet often unidentified cause. The aim of this study was to examine the bleeding patterns and prevalence of inherited bleeding disorders among females referred for HMB to a multidisciplinary adolescent haematology clinic. We retrospectively reviewed the first 105 patients (ages 8-18 years) referred to this specialty clinic from February 2009 to December 2011. Using menstrual bleeding questionnaires and medical records, data were extracted regarding demographics, bleeding patterns, frequency and types of bleeding disorders identified, and prescribed interventions. Sixty-two per cent of patients were diagnosed with a bleeding disorder, including platelet storage pool deficiency (36%), von Willebrand's disease (9%), other platelet function defect (8%), Ehlers-Danlos syndrome (7%) and combined bleeding disorders (2%). Comparison of the bleeding profiles for females with and without a bleeding disorder revealed only three factors that were significantly different, including the reported regularity of patients' periods (P = 0.02), description of period flow (P = 0.04) and number of days of each period that the bleeding was described as 'heavy' (P = 0.007). Bleeding disorders are prevalent in adolescent females presenting to a specialty clinic. Specifically, a relatively high proportion of adolescents were diagnosed with platelet storage pool deficiency. In our small population, menstrual bleeding profiles, as examined by a standardized questionnaire, could not identify females with an underlying bleeding disorder, demonstrating the important role of haemostasis testing in the evaluation of adolescents with HMB.

The PFA-100 ® does not predict delta-granule platelet storage pool deficiencies.

There are no published reports investigating the ability of the platelet function analyzer (PFA-100(®) ) to detect the presence of delta-granule platelet storage pool deficiencies (δ-PSPD), a common mild bleeding disorder. Prior studies of the PFA-100(®) and congenital platelet disorders have been limited by small numbers of patients with a variety of disorders. We examined PFA-100(®) results in a large paediatric patient population diagnosed specifically with δ-PSPD, and determined the relationship between PFA-100(®) and platelet electron microscopy (the gold standard for diagnosis). This study is a retrospective review of patients <19 years of age diagnosed with δ-PSPD at Nationwide Children's Hospital from 2008 to 2010. To examine the correlation between PFA-100(®) and average number of granules per platelet we used Spearman's Rho as a non-parametric measure of dependence. A total of 105 patients diagnosed with δ-PSPD were included, of which 99 patients underwent PFA-100(®) testing. Of those tested 46% had at least one abnormal closure time, whereas 16% had abnormal results for both cartridges. We found no statistical correlation between C-EPI closure time and average number of granules per platelet (ρ= -0.0095, P-value = 0.9328), nor between C-ADP closure time and the average number of granules (ρ = 0.0315, P-value = 0.7798). The PFA-100(®), a widely used screening test for suspected bleeding disorders, did not correlate with presence or severity of δ-PSPD as determined by platelet electron microscopy. When evaluating patients with suspected bleeding disorders, PFA-100(®) alone cannot be used to rule out the presence of a δ-PSPD.

The power of a standardized bleeding score in diagnosing paediatric type 1 von Willebrand's disease and platelet function defects.

A predictive standardized bleeding questionnaire (Vicenza score), previously validated for identifying individuals with type 1 von Willebrand's disease (VWD), has never been prospectively validated in tertiary care paediatric settings. The aim of this study was to assess the Vicenza score's predictive power in identifying type 1 VWD, low von Willebrand factor (VWF) and platelet function defects (PFD) in a prospective cohort of patients, 0-17 years old, referred to a paediatric haematology clinic for evaluation of a bleeding disorder. Before the initial visit, caregivers consented to answer the questionnaire via telephone. Patients' medical records were reviewed after haematological evaluation. VWF:Ag or VWF:RCo<30 IU dL(-1) were labelled 'definite type 1 VWD' while 30-50 IU dL(-1) were labelled 'Low VWF'. PFA-100 screening followed by abnormal electron microscopy and/or platelet aggregation studies diagnosed a PFD. At least one haemorrhagic symptom was present in 99 of the 104 children who completed the study (mean number of symptoms 2.87, mean Vicenza score 3.24). Eight met criteria for 'definite type 1 VWD', 23 for 'low VWF' and 13 for 'PFD'. The sensitivity, specificity, and positive and negative predictive value (NPV) of the Vicenza score demonstrated poor diagnostic utility with the exception of high specificity in ruling out 'definite type 1 VWD'. The NPV was comparably high with qualitative (>2 bleeding symptoms) and quantitative (Vicenza score ≥ 2) criteria. The Vicenza score has limited predictive value in paediatric tertiary care settings. While the NPV of excluding 'definite type 1 VWD' is high, simpler qualitative criteria is similarly predictive.