Una strana pancitopenia: dalla gestione in urgenza alla diagnosi genetica

Wiskott-Aldrich syndrome (WAS) is a rare X-linked genetic disorder caused by a mutation in the WAS gene that codes for the WASp protein, which is involved in the functioning of the cytoskeleton of non-erythroid haematopoietic cells. This mutation leads to a congenital immunity disorder characterised by immunodeficiency, microthrombocytopenia and eczema. Its incidence is 1 in 250,000 live-born males. Treatment options to date are haematopoietic stem cell transplantation (HSCT) from an HLA-matched donor or gene therapy. The paper described the case of Tommaso, a 5-month-old first-born child with WAS who represented a diagnostic challenge. At onset, the infant did not present with any pathognomonic elements of classic WAS, but a picture of trilinear cytopenia with severe anaemia. Only one single case is described in literature with the same genotype as Tommaso (WAS c.257G>A p. Arg86His) but characterised by a heterogeneous phenotype and different onset symptoms. The specific and timely diagnosis of WAS allowed Tommaso, at only 5 months of age, to undergo gene therapy, thus achieving a real recovery from the syndrome and significantly reducing the risks related to the toxicity of non-targeted therapies to which he would have been exposed in the future. This case teaches how the clinician must remain critical and inquisitive in the diagnostic process, always aiming to reach a specific diagnosis in order to start a targeted therapeutic programme in the shortest time possible.