Wiskott-Aldrich syndrome-2D82.1

Wiskott-Aldrich syndrome-2 (WAS2) is caused by a homozygous mutation in the WIPF1 gene on chromosome 2q31. The cellular abnormalities are thought to be due to impaired F-actin polymerization.

Laboratory tests show decreased numbers of CD8+ T cells, variably elevated Ig levels, especially IgE, low numbers of B cells, aberrant function of T and NK cells, and impaired T cell migration.

Death in early childhood is possible.

Lanzi et al (2012) reported an 11-day-old Moroccan infant with Wiskott-Aldrich syndrome-2. The infant was born to consanguineous parents who had previously lost a daughter at 4 months of age to recurrent infections.

The WAS2 patient had features of Wiskott-Aldrich syndrome, including recurrent infections, eczema, and thrombocytopenia. Immunologic analysis revealed low numbers of B cells and T cells, particularly CD8 -positive T cells. The number and percentage of natural killer (NK) cells were increased, but the functional activity of NK cells was drastically reduced. The patient's T cells showed normal proliferation in response to PHA but no response to anti-CD3. IL2 corrected the partial proliferation defect of T cells in a WAS patient but failed to correct the complete defect of T cell proliferation in the WAS2 patient. Platelet volume was normal.

Cord blood transplantation at 4.5 months of age restored immune function, and the WAS2 patient was healthy 16 months after the procedure.

1. Al-Mousa H et al. (2017) Hematopoietic stem cell transplantation corrects WIP deficiency. (Letter) J Allergy Clin. Immun 139: 1039-1040.
2. Conley ME et al (1992) Atypical Wiskott-Aldrich syndrome in a girl. Blood 80: 1264-1269.
3. Lanzi G et al (2012) A novel primary human immunodeficiency due to deficiency in the WASP-interacting protein WIP. J Exp Med 209: 29-34.