Anouk Donners

164 Chapter 9 concentrations in DBS, which is impossible with existing clotting assays. An additional benefit is the LC-MS/MS method’s robustness, lowering the interlaboratory variability present in neonatal screening [41]. Measuring FVIII in DBS can be also used for remote health monitoring (or ‘telemonitoring’) [42]. This usage would benefit PwHA who need to travel long distances for monitoring, such as in large countries with a low density of healthcare facilities or in low-income countries where diagnostic tools are unavailable. Although access to expensive FVIII therapy is limited in low-income countries, an accurate diagnosis could help PwHA to make the necessary lifestyle changes and begin physiotherapy. Telemonitoring might also be convenient for PwHA during a pandemic lockdown, as hospital visits may be reduced [43]. Critical notes A critical note for these future applications of LC-MS/MS analysis is the analysis run time. For instance, an overnight incubation step is required during sample preparation to dissociate FVIII from VWF. Thus, method optimisation is required to shorten the run time when this method is used in clinical practice because clinicians are accustomed to the rapid reporting of clotting assay results, usually within four hours, or within one hour if urgent. The current costs for LC-MS/MS analysis are only somewhat higher than other assays in Dutch hospitals. Since most clinical laboratories have adopted or will soon adopt this technique, the method costs will decrease. The competition of point-of-care devices with cartridges [44] is another aspect to consider. These devices can generate instant results from a single drop of 25 µL capillary blood by using a device the size of a mobile phone [45, 46]. However, these devices are not yet ready for the market, but their potential value is high, and they might take over a substantial part of the market after being launched. Certain critical notes regarding the ethical and timing issues of neonatal screening must also be addressed. For instance, few reports have been published on the ethical standpoints of the haemophilia A community towards screening. Two reports on this attitude in the UK have mentioned that most participants considered haemophilia a ‘liveable’ disability, and that affected families could be offered support by neonatal screening programmes rather than reducing the birth rate of affected children based on prenatal screening [47, 48]. In the rapidly changing treatment landscape of haemophilia A, patient- and clinician organisations should evaluate the need for neonatal screening. Therefore, patient and clinician organisations in the Netherlands could form focus groups and conduct survey research to study this topic. Another issue is the timing of screening. Neonatal screening (i.e., post-delivery) is too late to prevent birth-related bleeds, suggesting a need for prenatal haemophilia A screening. More research is needed to determine whether haemophilia A is better suited for neonatal or prenatal screening. The ethics and timing issues should be clear before developing a DBS screening method