, according to a retrospective analysis.
Marc Trossaert, MD, PhD, of the CHU de Nantes, France, and colleagues conducted a retrospective analysis of 64 consecutive patients diagnosed with acquired hemophilia A over a period of 15 years (2000-2015). Data were obtained from institutional databases at the Toulouse and Nantes university hospitals in France.
Data collected included patient demographics, comorbidities, biological factors, and information related to immunosuppressive therapy. The findings of the study were published in Haemophilia.
To ascertain normal parameters and uses of the FVIII/W ratio, the team assessed FVIII:C and VWF:Ag levels of 40 healthy individuals and normal parameters of the ratio were defined using these levels.
Among the 64 patients with acquired hemophilia A who were enrolled in the study, 55 patients achieved complete remission. Of that group, 44 patients did not relapse. Researchers had follow-up data of at least 1 year for 22 of these patients. They found that the FVIII/W ratio remained within normal parameters for all 22 patients.
Researchers had follow-up data on 5 of the 11 patients who relapsed during the study period. For 4 of the patients, a decrease of FVIII/W ratio was the first indicator of relapse. In the fifth patient, an abnormal activated partial thromboplastin time (aPTT) displayed before the changes were observed in the FVIII/W ratio.
Dr. Trossaert and his colleagues acknowledged that a key limitation of the study was the retrospective design.
“We cannot eliminate the fact that in these patients less frequent testing may have influenced the chance of seeing a low FVIII/W ratio,” they wrote.
The biomarker now needs to be studied in larger cohorts, the researchers suggested.
No funding sources were reported. The authors reported having no conflicts of interest.
SOURCE: Trossaert M et al. Haemophilia. 2019 May 2. doi: 10.1111/hae.13752.