RESUMEN
BACKGROUND: Hypereosinophilic syndromes are characterized by sustained overproduction of eosinophils, leading to eosinophilic infiltration, mediator release and multi-organ damage. CASE REPORT: A 67 year old male was referred to our Department for investigation of a persistent mild-to-moderate eosinophilia, identified 10 years previously and unresponsive to corticosteroid treatment. No other alterations were present in his differential blood count and physical examination was unremarkable. Allergic, rheumatologic and iatrogenic causes of eosinophilia were excluded by clinical history, skin-prick tests and blood and stool analysis. Iliac crest bone marrow aspiration and biopsy were performed, revealing normal cellularity with an increased eosinophil count (6%). RT-PCR of the aspirate revealed the presence of transcripts of ETV6/PDGFR-beta t(5;12) gene fusion. Karyotype analysis was normal and no mutation in PDFGR-alpha was identified. There was no evidence in analytic or imaging studies of cardiac, skin, neurologic, pulmonary or splenic involvement. A skin biopsy showed no evidence of pathologic infiltration. Initially the patient was treated with a 100 mg daily dose of imatinib mesylate, a specific inhibitor of the tyrosine-kinase domain of PDGFR. Subsequently, the daily dosage was increased to 200 mg/day to obtain eosinophil count normalization. Currently, he is under monthly hematologic and hepatic function screening. No drug side effects have been reported. CONCLUSION: This patient was diagnosed with a rare myeloproliferative variant of hypereosinophilic syndrome due to a t(5;12) ETV6/PDGFR-beta translocation. Imatinib mesylate, previously used successfully in syndromes associated with PDFGR-alpha mutations, showed efficacy in the context of this mutation as well.
Asunto(s)
Síndrome Hipereosinofílico/genética , Proteínas Proto-Oncogénicas c-ets/genética , Receptor beta de Factor de Crecimiento Derivado de Plaquetas/genética , Proteínas Represoras/genética , Translocación Genética , Anciano , Humanos , Masculino , Proteína ETS de Variante de Translocación 6RESUMEN
Although the standard of care for cow's milk (CM) allergy is strict food avoidance, oral immunotherapy (OIT) is being widely investigated as an alternative management option in certain cases. Immediate adverse reactions to OIT have been described, but its long-term effects are much less often reported. We present the case of a girl diagnosed with IgE-mediated CM allergy that was proposed for our CM OIT protocol at the age of 3 years. The first sessions (dose escalation up to 5 ml) were well tolerated, however eight hours after her daily morning dose of 5 ml CM the child developed late episodes of vomiting. No other symptoms, particularly immediately after CM ingestion, were reported. These episodes became progressively worse and on the third day she presented mild dehydration and blood eosinophilia. After OIT interruption, a progressive clinical improvement was observed. An esophageal endoscopy was performed, showing signs of eosinophilic esophagitis (EoE) with peak 20 eosinophils/hpf. After treatment with topical swallowed fluticasone (500 mcg bid) and a CM-free diet for 4 months, the child was asymptomatic and endoscopy and biopsy findings were normal.The long-term effects of milk OIT are still in part unknown. We hypothesize that eosinophilic esophagitis may have been a consequence of OIT in this case. The findings seem to indicate that food allergy may play a role in the pathogenesis of esophageal eosinophilia and stress the importance of a well programmed long-term follow-up of patients that have undergone milk OIT.
