HPA-1a antigen tolerance induction by maternal-fetal antigen exposure

HPA-1a antigen tolerance induction by maternal-fetal antigen exposure - tolerance induction by maternal-fetal antigen exposure

Status

Active, not recruiting

Phases

Unknown

Study type

Observational

Source

NL-OMON

Registry ID

NL-OMON30661

Enrollment

Registered

2007-07-12

Start date

2007-01-01

Completion date

Unknown

Last updated

2024-06-18

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Allo immunisatie tegen een trombocyten antigeen Neonatal AlloImmune thrombocytopenia AND platelet antagonism AND shortage of platelets in newborns

Interventions

None listed

Eligibility

Age

18 Years to 99 Years

Inclusion criteria

Inclusion criteria: Mothers of women with HPA-1a antibodies

Exclusion criteria

Exclusion criteria: no specific exclusioncriteria

Design outcomes

Primary

Measure	Time frame
Primary study parameter is HPA-1a type of the "grandmothers". 2% of the Caucasian population is HPA-1a negative (HPA-1b1b). If HPA-1a antibodies are only produced by HPA-1a negative women with HPA-1a negative mothers (grandmothers) 20 cases will be enough to show statistical significance. Calculation: In the Caucasian population the HPA-1 fenotyping is distributed as follows: HPA-1a1a 72% HPA-1a1b 26% HPA-1b1b 2% HPA-1b1b mothers will have a HPA-1a1b or HPA-1b1b mother (grandmother). The ratio HPA-1a1b:HPA-1b1b for these grandmothers is 93:7. If there is a 100% tolerance induction all grandmothers must be HPA-1b1b and the statistical significance (Chi Square p1:64) and 20 women with a low antibody titer (4 of 20) is expected in the high antibody titer group but not in the low antibody titer group.	—

Measure

Time frame

Primary study parameter is HPA-1a type of the "grandmothers". 2% of the Caucasian population is HPA-1a negative (HPA-1b1b). If HPA-1a antibodies are only produced by HPA-1a negative women with HPA-1a negative mothers (grandmothers) 20 cases will be enough to show statistical significance. Calculation: In the Caucasian population the HPA-1 fenotyping is distributed as follows: HPA-1a1a 72% HPA-1a1b 26% HPA-1b1b 2% HPA-1b1b mothers will have a HPA-1a1b or HPA-1b1b mother (grandmother). The ratio HPA-1a1b:HPA-1b1b for these grandmothers is 93:7. If there is a 100% tolerance induction all grandmothers must be HPA-1b1b and the statistical significance (Chi Square p1:64) and 20 women with a low antibody titer (4 of 20) is expected in the high antibody titer group but not in the low antibody titer group.

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Secondary

Measure	Time frame
no secundary study parameters	—

Countries

Netherlands

Outcome results