Acute basophilic leukaemia in a three-month-old calf.

A three-month-old female Holstein-Friesian calf was presented with acute tetraparesis. After neurological examination a multifocal lesion in the central nervous system was suspected with the most pronounced lesions between the third thoracic and the third lumbar vertebrae. Haematological examination revealed moderate anaemia as well as severe thrombocytopenia, neutropenia and leucocytosis. A blood smear and bone marrow aspirate exhibited predominantly blasts with basophilic granulation leading to a diagnosis of acute (myeloid) leukaemia with involvement of the basophilic lineage or an acute basophilic leukaemia. Magnetic resonance imaging revealed spinal cord compression; at necropsy, extensive localised haemorrhages extending into the thoracic vertebral canal were found. Histopathology revealed a large population of blast cells in several tissues including the meninges. Due to multifocal detection of neoplastic cells in the vascular system, neoplasia of the haematopoietic system was assumed in agreement with haematological findings. Signs of paresis could be explained by intramedullary spinal cord haemorrhage and myeloid infiltrations of meningeal vessels. In conclusion, despite its rarity, acute myeloid leukaemia with involvement of the basophilic lineage may be considered in diagnosing calves with progressive deteriorating general condition, paresis, leucocytosis with moderate basophilic differentiation or haemorrhagic disorders.

The green tea polyphenol (-)-epigallocatechin-3-gallate inhibits leukocyte activation by bacterial formylpeptide through the receptor FPR.

Although green tea polyphenol catechin is considered as a potential anti-inflammatory agent, its effect on bacterial component-induced inflammation has been poorly investigated. We examined the capacity of epigallocatechin gallate (EGCG) to regulate leukocyte responses to bacterial chemotactic peptide N-formylmethionyl-leucyl-phenylalanine (fMLF), which is recognized by a human G protein-coupled receptor FPR on phagocytic leukocytes. Pretreatment of human monocytic cells or FPR-transfected rat basophilic leukemia cells (ETFR cells) with EGCG significantly inhibited fMLF-induced chemotaxis. Intraperitoneal administration of EGCG in mice suppressed fMLF-induced leukocyte infiltration into the air pouch created in the skin. Mechanistic studies revealed that EGCG dose-dependently suppressed fMLF-induced calcium flux in monocytic cells and ETFR cells. fMLF-induced ETFR cell migration was significantly inhibited by a specific MEK1/2 inhibitor, PD98059, which was associated with reduction in fMLF-induced ERK1/2 phosphorylation. These results suggest that EGCG inhibits FPR-mediated leukocyte activation thus is a promising anti-inflammatory compound.

[A case of de novo acute basophilic leukaemia: diagnostic criteria and review of the literature]. / A propos d'un cas de leucémie à basophiles de novo: critères diagnostiques et revue de la littérature.

We report a case of a de novo acute basophilic leukaemia, revealed by an infectious pneumopathy in a 73 year old man. The full blood count revealed an hyperleucocytosis associated with an unregenerative normocytic normochrom anaemia and a thrombocytopenia. The blood and bone marrow smears showed a mixture of undifferentiated blast cells and basophiloblasts (high nucleo-cytoplasmic ratio, coarse basophilic cytoplasmic granules), along with basophilic precursors and basophilic polymorphonuclears. All the blasts were MPO negative but positive for the toluidine blue metachromatic coloration, which is considered as consistent with basophilic lineage. Immunophenotypic studies showed myeloid blasts, without maturity marker, CD 117 negative and CD203 cytoplasmic positive, the latter known to be highly representative of the basophilic lineage. This very clear-cut phenotype, associated with the morphology of cells, were arguments to ascertain the basophilic lineage of the blasts without the need of electron microscopic study. Cytogenetic and RNA analysis revealed the presence of a Philadelphia chromosome and of a BCR-ABL transcript with the unusual junction e6a2. Thus, imatinib was added to the conventional chimiotherapy and the patient is currently in complete remission. This clinical prompted allows us to review the literature on acute basophilic leukaemia and to state on the different diagnostic criteria of this rare disorder.

Acute basophilic leukemia: case report.

The term "basophilic leukemia" has been in use for 75 years. However, consistent diagnostic criteria are lacking. This is due to the rarity of the disease and to the routine unavailability of special tests that are often required to confirm a diagnosis. We report an unusual case of acute basophilic leukemia in a child who was referred to our Center, arriving with partially treated acute lymphoblastic leukemia. Basophilic differentiation on light microscopy was evident from the coarse basophilic granules in blasts, a progressive maturation of blasts toward basophils, and toluidine positivity on cytochemistry. Blasts showed a myeloid immunophenotype (CD13+, CD33+, CD117+) with a characteristic dual positivity for CD34 and CD25, highly suggestive of basophilic nature of the blasts. Conventional cytogenetic studies revealed translocation t(8;21)(q22;q22). A diagnosis of acute basophilic leukemia with t(8;21) was made. Review of pre-therapy slides showed features consistent with AML-M2 with basophilia. There were no basophilic blasts. With these features, a diagnosis of acute basophilic leukemia secondary to AML-M2 was made. In our patient, basophilic leukemia appears to have evolved from selective clonal proliferation of "basophil-committed blasts" during the course of the disease in a case of AML-M2 with basophilia.

Acute basophilic leukemia lacking basophil-specific antigens: the importance of cytokine receptor expression in differential diagnosis.

De novo acute basophilic leukemia (ABL) is a rare form of myeloid leukemia. The low prevalence of ABL makes it difficult to define its clinical characteristics and to establish an effective therapeutic protocol. We present here a case of de novo ABL in a 64-year-old Japanese man. The diagnosis of ABL depended on the following: (1) metachromasia with toluidine blue stain, (2) intracytoplasmic theta granules identified by electron microscopy, and (3) findings obtained from extensive immunophenotypic analysis. Although blast cells lacked basophil-specific antigens such as CDw17, CD88, and FcepsilonRI, an expression profile of cytokine receptors including CD116 (GM-CSF receptor), CD117 (c-kit), and CD123 (IL-3 receptor alpha) helped to define the cellular lineage in our case. The patient achieved complete remission with intensive chemotherapy composed of idarubicin and cytosine arabinoside and was disease free during the following 30 months. We propose that immunophenotyping, especially focusing on cytokine receptors, is useful in diagnosing ABL.

Acute basophilic leukemia presenting with abnormal liver function tests and the absence of blast cells in the peripheral blood.

Acute basophilic leukemia is an uncommon form of acute leukemia, rarely occurring as a de novo disease. We describe a case of de novo acute basophilic leukemia occurring in a 47-year-old man who presented with abnormal liver function tests in the absence of leukemic infiltration of the liver. We postulate that this presentation occurred as a consequence of pathophysiological features of the malignant basophilic blast cells.

[Acute basophilic leukemia with an intense erythroblastic reaction]. / Leucemia aguda a basófilos con intensa reacción eritroblástica.

A patient is presented who had acute basophilic leukaemia with intense erythroblastic reaction. The patient, a 66 year-old man, complained of general malaise, increased abdominal perimeter and melena. Leucocytosis, as well as severe anaemia and thrombocytopenia, were found in his peripheral blood. Basophils were present in all maturation stages, along with 7% blast-cells showing basophilic stippling, and there were 210 erythroblasts per 100 white cells. Erythropoietic hyperplasia (75%) was found in the bone-marrow aspirate, without dyserythropoietic signs; the PAS-stain reaction was negative. Of the non-erythroid cells, 63% were basophils and 34% blast-cells, some of them showing basophilic stippling plus metachromasia for tholuidin-blue, positivity for omegaexonuclease and negativity for peroxidase stains. The diagnosis of acute basophilic leukaemia was confirmed upon demonstration of basophilic stippling in the ultrastructural study of the blast-cells. The patient developed acute liver failure and renal insufficiency which led him to death. The basis of the diagnosis of acute basophilic leukaemia is discussed, as well as the differential diagnosis with other conditions presenting with basophilia and the probably reactive erythroblastic increase appearing in this case.

[Acute basophilic leukemia: a case report].

A 56-year-old woman was admitted to our hospital in January, 1990 because of fever and petechiae. Leukocyte count of peripheral blood showed 41,000/microliters with 89% immature cells, and bone marrow was normocellular with 96.2% immature cells. They were medium to large in size, positive for peroxidase staining, CD-13 and CD-33. Half of them contained azurophilic granules. They showed metachromasia by toluidine blue, contained basophilic granules in electron microscopic examination and reacted to G-CSF, G-CSF and IL-3. She was diagnosed as acute basophilic leukemia and treated with BHAC-DMP and B triple-V regimen, but remission was not attained. She died of peritonitis due to gastrointestinal tract perforation and pneumonia in March, 1990. This is the fifteenth case of acute basophilic leukemia reported in Japan, and the hematological examinations performed in this patient were demonstrated.