Interference of in vitro hemolysis complete blood count.

BACKGROUND: Hemolysis may occur in vivo, under pathological conditions, or in vitro, related to pre-analytical errors. Hemolyzed samples may produce unreliable results, leading to errors in diagnostic and monitoring evaluations. This study aims to evaluate the interference of in vitro hemolysis on the interpretation of the parameters of the blood cell-counting performed by the impedance method. METHODS: Peripheral blood samples were collected in anticoagulant K2-EDTA and subsequently divided into three 1.0 mL aliquots. The first aliquot was not subjected to any intervention, and the second and third aliquots were passed 5 and 10 times through a small-gauge needle to produce scalar amounts of hemolysis. Hematological tests were performed by Hemacounter 60-RT 7600® . RESULTS: Comparison of the samples with different degrees of hemolysis showed a decrease in red blood cells count and hematocrit counts and increase in mean corpuscular hemoglobin concentration and platelet count in samples with a high degree of hemolysis. According to the accepted clinical point of view, the samples with a high degree of hemolysis exceeded the desirable bias, presenting decrease in red blood cells count, hematocrit and mean corpuscular volume, and increase in red cell distribution width, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and platelet counts. However, samples with a mild degree of hemolysis showed only a slight increase in mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, and platelet count. CONCLUSION: This study demonstrated that in vitro hemolysis can decrease the clinical and analytical reliability of the assessment of the blood count.

Isolated trisomy 11 in de novo acute myeloid leukemia / Trissomia 11 isolada em leucemia mielóide aguda de novo

The real mechanism involved in trisomies and leukemogenesis remains unknown and more information about this connection is essential, but unfortunately the clinical outcome and hematological profile of patients with isolated trisomy 11 and AML have not been well characterized. Considering the limited data on the specific disease entity, the current report describes two cases of de novo acute monocytic leukemia (AMoL) and isolated +11, in which this event was further characterized.

O mecanismo envolvido em trissomias e leucemogênese permanece não esclarecido e mais dados sobre esta relação são fundamentais, mas infelizmente os resultados clínicos e o perfil hematológico dos pacientes com trissomia 11 isolada e LMA ainda não foram bem caracterizados. Considerando o limitado número de informações, este relato descreve dois casos de leucemia monocítica de novo e trissomia 11 onde este evento foi caracterizado.

A rare case of Acute Lymphocytic Leukemia (ALL) presenting with double Philadelphia chromosome: relapse or secondary leukemia?

The Philadelphia chromosome is observed in 5 percent of pediatric acute lymphocytic leukemia (ALL) and in 25 percent to 50 percent of adult ALL cases, and is associated with poor prognosis. Double Ph in a hyperdiploid karyotype is common in chronic myeloid leukemia (CML), but rarely found in ALL. We report here the case of a girl diagnosed with ALL at 7 years of age. After treatment with the pediatric protocol BFM 83 for ALL, she stayed in continuous complete remission for nine years. At age 19, she was re-admitted with a white blood cell count of 6.8 x 10(9)/L with 3 percent blasts, and a platelet count of 65 x 109/L. Bone marrow aspirate showed 92.6 percent lymphoid blast cells, and chromosome analysis after G-banding revealed the karyotype 51,XX,+?5,t(9;22)(q34.1;q11.2),+16,+20,+21,+der(22)t(9;22)(q34.1;q11.2) [10]/46,XX[1]. FISH analysis for the BCR/ABL fusion showed 56 percent of interphase cells with two fusion signals, 30 percent with one, and 6 percent with three. Double Ph is rare in relapsed leukemia, and the possibility of secondary leukemia cannot be ruled out