FIP1L1-PDGFRA positive chronic eosinophilic leukemia in Tunisian patients.
Hypereosinophilic syndromes (HES) are a heterogenous group of rare disorders characterized by sustained and otherwise unexplained overproduction of eosinophils with organ involvement and consecutive dysfunction. Detection of the FIP1L1-PDGFRA fusion gene or the corresponding cryptic 4q12 deletion in HES supports the diagnosis of chronic eosinophilic leukemia (CEL) and provides a molecular explanation for the pathogenesis of this disorder. We screened seven Tunisian patients fulfilling the WHO criteria of HES for the presence of the FIP1L1-PDGFRA fusion gene using nested reverse transcription polymerase chain reaction on peripheral blood samples. Four of the seven patients were positive for this fusion gene. Sequence analysis revealed a substantial heterogeneity of the fusion transcripts due to the involvement of several FIP1L1 exons. All patients were male. The median age at diagnosis was 24 years (range, 18-50); one patient had a history of hypereosinophilia of more than 10 years. Two patients had clinically important and symptomatic eosinophilic endomyocardial disease with thrombotic events. Splenomegaly was constant in FIP1L1-PDGFRA positive CEL but not in the other HES patients (only 1/3).
Menif
S
S
Laboratoire d'hématologie moléculaire et cellulaire, institut Pasteur de Tunis, Le-Belvedere, Tunis, Tunisie. samia.menif@rns.tn
Omri
H
H
Hafsia
R
R
Ben Romdhane
N
N
Turki
S
S
Meddeb
B
B
Dellagi
K
K
D000293:Adolescent; D000328:Adult; D002874:Chromosome Mapping; D002908:Chronic Disease; D006801:Humans; D017681:Hypereosinophilic Syndrome / Q000453:epidemiology / Q000235:genetics* / Q000473:pathology; D008198:Lymph Nodes / Q000473:pathology; D008875:Middle Aged; D015514:Oncogene Proteins, Fusion / Q000235:genetics*; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014416:Tunisia / Q000453:epidemiology; D039221:mRNA Cleavage and Polyadenylation Factors / Q000235:genetics*
D015514:Oncogene Proteins, Fusion; D039221:mRNA Cleavage and Polyadenylation Factors; C479819:FIP1L1-PDGFRA fusion protein, human; D020796:Receptor, Platelet-Derived Growth Factor alpha