The usefulness of the platelet function analyser (PFA-100) in screening for underlying bleeding disorders in women with menorrhagia

Point-of-Care Testing in Patients with Hereditary Disorders of Primary Hemostasis: A Narrative Review

Inherited disorders of primary hemostasis, such as von Willebrand disease and congenital platelet disorders, can cause extensive, typically mucocutaneous bleeding. Assays to diagnose and monitor these disorders, such as von Willebrand factor activity assays and light transmission aggregometry, are performed in specialized hemostasis laboratories but are commonly not available in local hospitals. Due to the complexity and relative scarcity of these conventional assays, point-of-care tests (POCT) might be an attractive alternative in patients with hereditary bleeding disorders. POCTs, such as thromboelastography, are increasingly used to assess hemostasis in patients with acquired hemostatic defects, aiding clinical decision-making in critical situations, such as during surgery or childbirth. In comparison, the use of these assays in patients with hereditary hemostasis defects remains relatively unexplored. This review aims to give an overview of point-of-care hemostasis tests in patients with hereditary disorders of primary hemostasis. A summary of the literature reporting on the performance of currently available and experimental POCTs in these disorders is given, and the potential utility of the assays in various use scenarios is discussed. Altogether, the studies included in this review reveal that several POCTs are capable of identifying and monitoring severe defects in the primary hemostasis, while a POCT that can reliably detect milder defects of primary hemostasis is currently lacking. A better understanding of the strengths and limitations of POCTs in assessing hereditary defects of primary hemostasis is needed, after which these tests may become available for clinical practice, potentially targeting a large group of patients with milder defects of primary hemostasis.

A Case of Chronic Thrombocytopenia in a 17-Year-Old Female

Storage pool deficiency (SPD) is a group of rare platelet disorders that result from deficiencies in α-granules, δ-granules, or both. One type of α-SPD is gray platelet syndrome (GPS), caused by mutations in the neurobeachin-like 2 (NBEAL2) gene that results in a bleeding diathesis, thrombocytopenia, splenomegaly, and progressive myelofibrosis. Due to the lack of α-granules, platelets have a gray and degranulated appearance by light microscopy. However, definitive diagnosis of GPS requires confirmation of α-granule deficiency by electron microscopy. Treatment is nonspecific, with the conservative utilization of platelet transfusions being the most important form of therapy. We present a case of a 17-year-old female with a past medical history of thrombocytopenia, first identified at the age of five. Her clinical symptomatology included chronic fatigue, gingival bleeding, bruising, menorrhagia, and leg pain. This report will discuss both the clinical and the pathophysiologic aspects of this rare platelet disorder.

The frequency of menorrhagia and bleeding disorders in university students

STUDY OBJECTIVE

Menorrhagia is an important health problem in women of reproductive age. The aims of this study were to assess the prevalence of menorrhagia and hemostatic abnormalities associated with menorrhagia in university students.

METHODS

The pictorial blood assessment chart (PBAC) was used to identify students with menorrhagia. Those with a PBAC score > 100 were examined by pelvic ultrasound and laboratory tests including complete blood count, levels of clotting factors, von Willebrand factor antigen, and ristocetin cofactor activity and Platelet Function Analyser-100 (PFA-100). Platelet aggregation was studied in students with prolonged PFA-100 closure time.

RESULTS

Menorrhagia was identified in 82 (21.8%) of 376 students. Six of 82 students who had pelvic pathologies were excluded. Eleven (14.5%) of the remaining 76 students were found to have bleeding disorders, including von Willebrand disease in five (6.5%), platelet function disorder in four (5.2%), and clotting factor deficiencies in two (2.6%).

CONCLUSIONS

Menorrhagia is a common but mostly unrecognized and untreated problem among university students. Underlying bleeding disorders are not rare and require comprehensive hemostatic evaluation for identification.

Utility of platelet function analyzer as a screening tool for the diagnosis of von Willebrand disease in adolescents with menorrhagia

BACKGROUND

Von Willebrand disease (VWD), and in particular, VWD type 1 and low VW factor (defined as Von Willebrand Ristocetin cofactor activity (RCoF) <30 and <50 IU/dl, respectively with normal multimers) are frequently detected in adolescents with menorrhagia and both groups benefit from similar management. Platelet function analyzer (PFA-100®) is often used as a screening test to detect VWD. We analyzed the utility of PFA-100® as a screening tool in the detection of VWD type 1 and low VW factor (VWF) in an exclusive adolescent population with menorrhagia.

METHODS

The study population consisted of adolescents with menorrhagia who had simultaneously drawn blood samples for VWD and PFA-100®. Abnormal PFA-100® was defined as values >183 seconds for collagen/epinephrine and/or >126 seconds for collagen/ADP.

RESULTS

Of a total of 235 patients tested, 23 patients had RCoF <50 IU/dl and normal multimer patterns. Statistical analysis of the utility of PFA-100® in detecting RCoF <50 IU/dl with normal multimers yielded sensitivity, specificity, positive predictive, and negative predictive values of 52%, 89%, 34%, and 95%, respectively.

CONCLUSIONS

Based on our results, PFA-100® was not sufficiently sensitive to detect RCoF values <50 IU/dl with normal multimer patterns in teen-aged women with menorrhagia. We conclude that in the setting of adolescent menorrhagia, PFA-100® does not have utility as an initial screening test for the diagnosis of VWD and in particular, low VWF and that clinicians need to be aware of this limitation of PFA-100® while evaluating adolescents with menorrhagia.