Challenges in the laboratory diagnosis and management of von Willebrand disease in South Africa

Background: South African von Willebrand disease (VWD) care is challenged by the lack of laboratory testing standardisation, lack of national clinical guidelines, limited undergraduate exposure to bleeding disorders and limited pharmacological resources. As the only reference testing facility performing VWD confirmatory testing, our experience in the diagnosis of the majority of VWD cases in South Africa has highlighted many areas where improvements are desperately needed.
Methods: We conductedd a retrospective audit of 250 VWD cases at our laboratory where we calculated the percentage misdiagnoses should only the von Willebrand factor (VWF) levels and the ristocetin cofactor activity assays be used.
Results: We have shown that performing a limited panel of VWD testing (VWF antigen and ristocetin cofactor activity only) could lead to the misdiagnosis of VWD in up to 77% of cases analysed at our laboratory. If the multimeric analysis was to be included in the diagnostic setup, together with the limited panel, still 20% of patients would be misdiagnosed. The underdiagnosis and under-reporting of VWD greatly underestimates the burden of the disease and the impact on the healthcare system.
Conclusions: Future advancements in VWD care in South Africa should be focused on correcting these shortcomings.