Paroxysmal nocturnal hemoglobinuria clones in children with acquired aplastic anemia: a multicentre study | Aplastic Anemia and MDS International Foundation

Paroxysmal nocturnal hemoglobinuria clones in children with acquired aplastic anemia: a multicentre study

Journal Title: 
PLoS One
Author(s): 
Timeus F, Crescenzio N, Longoni D, Doria A, Foglia L, Pagliano S, Vallero S, Decimi V, Svahn J, Palumbo G, Ruggiero A, Martire B, Pillon M, Marra N, Dufour C, Ramenghi U, Saracco P
Primary Author: 
Timeus F
Original Publication Date: 
Wednesday, July 9, 2014

A multicentre study evaluating the presence of glycosil phosphatidyl-inositol (GPI)-negative populations was performed in 85 children with acquired aplastic anemia (AA). A GPI-negative population was observed in 41% of patients at diagnosis, 48% during immune-suppressive therapy (IST), and 45% in patients off-therapy. No association was found between the presence of a GPI-negative population at diagnosis and the response to IST. In addition, the response rate to IST did not differ between the patients who were GPI-positive at diagnosis and later developed GPI-negative populations and the 11 patients who remained GPI-positive. Two patients with a GPI-negative population >10%, and laboratory signs of hemolysis without hemoglobinuria were considered affected by paroxysmal nocturnal hemoglobinuria (PNH) secondary to AA; no thrombotic event was reported. Excluding the 2 patients with a GPI-negative population greater than 10%, we did not observe a significant correlation between LDH levels and GPI-negative population size. In this study monitoring for laboratory signs of hemolysis was sufficient to diagnose PNH in AA patients. The presence of minor GPI-negative populations at diagnosis in our series did not influence the therapeutic response. As occasionally the appearance of a GPI-negative population was observed at cyclosporine (CSA) tapering or AA relapse, a possible role of GPI-negative population monitoring during IST modulation may need further investigation.