Pseudohemophilia of Erik von Willebrand caused by homozygous one nucleotide deletion in exon 18 of the VW-factor gene

Table 4 Laboratory phenotype and clinical symptoms in 69 patients with true von Willebrand factor deficiency type 1 heterozygous for the von Willebrand factor null allele (parents of type III von Willebrand disease)

Author		Zhang et al[13]		Eikenboom et al[15]
Number of patients		25	17	14		6
Blood Group		A	O	A		O
FVIII: C (%)	Mean	81	74	93		81
	Range	37-121	11-128	69-138	58-93
VWF: Ag	Mean	45	32	61
	Range	13-94	12-70	37-98	40-66	52
VWF: RCo	Mean	-	-	56		53
	Range	-	-	30-92	39-68
Mild bleedings1		13	11	1		1
		52%	65%	7%		17%

¹Mild bleeding was defined by one or two bleeding symptoms mainly epistaxis, bruises and/or prolonged menstruations without abnormal bleeding after both extraction or surgy, hemarthros or muscle bleeding. VWF: von Willebrand factor.