Parental consanguinity and the risk of primary immunodeficiency disorders: report from the Kuwait National Primary Immunodeficiency Disorders Registry.

Background: It is proposed that consanguineous marriages increase the risk of primary immunodeficiency disorders (PID). The aim of this study is to review the frequency and pattern of parental consanguinity among PID patients and to determine its effects on the distribution of different PID, the patients' performance status and the risk of death.

Method: The data was obtained from the Kuwait National Primary Immunodeficiency Disorders Registry. The coefficient of inbreeding was determined for each patient and the patients' overall performance status was assessed using the Lansky Play Performance Scale and the Karnofsky Performance Scale.

Results: A total of 128 patients with PID from 99 families are reported. A family history suggestive of PID and parental consanguinity was reported in 44 and 75% of the patients respectively, while the mean coefficient of inbreeding was 0.044067. There were statistically significant associations between both a family history of PID and parental consanguinity and PID category, the risk of death and the patients' overall performance status. Evidence of autosomal recessive transmission of disease was present in 44% of the patients.

Conclusions: Parental consanguinity is a risk factor for the development of PID. There is a need to increase the public awareness of the health consequences of consanguineous marriages.