Acute lymphoblastic leukemia with eosinophilia lacking peripheral blood leukemic cell: a rare entity

B-cell acute lymphoblastic leukemia associated with hypereosinophilia: a case report and brief literature review

Few cases of B-cell acute lymphoblastic leukemia (B-ALL)-eosinophilia (ALL-eo) association have been reported. The lack or absence of blasts in the peripheral blood smear (PBS) along with urticarial rash, fever, arthralgia, myalgia, sweating, and dyspnea are common features of this condition. Herein, we report a 16-year-old male patient admitted to the emergency department with urticaria and generalized itching. PBS was examined, and eosinophils (90%) were seen in different fields. However, blast cells were not seen in PBS. In a bone marrow examination, terminal deoxynucleotidyl transferase-positive and CD20-positive lymphoid blasts were reported along with eosinophilia. Eventually, the B-ALL diagnosis was confirmed for the patient, and he was started on the Berlin-Frankfurt-Münster chemotherapy regimen. The association of B-ALL with hypereosinophilia is a rare condition. We hope this case report and literature review can help clinicians to manage this rare condition properly.

Pediatric Acute Lymphoblastic Leukemia With Hypereosinophilia and IDH2 Gene Mutation: A Case Report and Literature Review

Eosinophilia is a rare presentation of acute lymphoblastic leukemia (ALL) within the pediatric population. In this report, we present a patient with pre-B ALL and eosinophilia in the setting of an isocitrate dehydrogenase-2 gene mutation. These mutations have been described in patients with acute myeloid leukemia but in very few patients with ALL.

B-ALL With t(5;14)(q31;q32); IGH-IL3 Rearrangement and Eosinophilia: A Comprehensive Analysis of a Peculiar IGH-Rearranged B-ALL

Background: B-cell acute lymphoblastic leukemia associated with t(5;14)(q31;q32); IGH-IL3 is an exceptional cause of eosinophilia. The IGH enhancer on 14q32 is juxtaposed to the IL3 gene on 5q31, leading to interleukin-3 overproduction and release of mature eosinophils in the blood. Clinical, biological and outcome data are extremely scarce in the literature. Except for eosinophilia, no relevant common feature has been highlighted in these patients. However, it has been classified as a distinct entity in the World Health Organization classification.

Cases Presentation: Eight patients with t(5;14)(q31;q32) treated by French or Austrian protocols were retrospectively enrolled. Array comparative genomic hybridization, multiplex ligation-dependent probe amplification or genomic PCR search for IKZF1 deletion were performed in 7. Sixteen patients found through an exhaustive search in the literature were also analyzed.

For those 24 patients, median age at diagnosis is 14.3 years with a male predominance (male to female ratio = 5). Eosinophilia-related symptoms are common (neurologic in 26%, thromboembolic in 26% or pulmonary in 50%). Median white blood cells count is high (72 × 10⁹/L) and linked to eosinophilia (median: 32 × 10⁹/L). Peripheral blasts are present at a low level or absent (median: 0 × 10⁹/L; range: 0–37 × 10⁹/L). Bone marrow morphology is marked by a low blast infiltration (median: 42%). We found an IKZF1 deletion in 5 out of 7 analyzable patients Outcome data are available for 14 patients (median follow-up: 28 months): 8 died and 6 are alive in complete remission.

Some of these features are concordant with those seen in patients with other IGH-rearranged B-cell acute lymphoblastic leukemias: young age at onset, male sex, low blast count, high incidence of IKZF1 deletion and intermediate prognosis.

Conclusion: Based on shared epidemiological and biological features, B-cell acute lymphoblastic leukemia with t(5;14)(q31;q32) is a peculiar subset of IGH-rearranged B-cell acute lymphoblastic leukemia with an intermediate prognosis and particular clinical features related to eosinophilia.

Grey eosinophils in a Miniature Schnauzer with a poorly differentiated mast cell tumor

A 10-year-old female spayed Miniature Schnauzer was presented for investigation of an intra-nasal mass. The mass was diagnosed by histopathologic examination as an undifferentiated round cell neoplasm with an infiltrate of segmented leukocytes, interpreted as neutrophilic inflammation. The mass was treated with palliative radiation and systemic chemotherapy due to the presence of regional lymph node metastasis. During subsequent monitoring over several months, the peripheral leukocyte concentration was repeatedly within reference intervals to slightly increased with low numbers of toxic neutrophils. Four months after the initial diagnosis, there was a significant leukocytosis of 66 100 cells/μL, and 39 700 cells/μL of the leukocytes had variably mature, lobulated, and hypolobulated nuclei, and grey cytoplasm with clear vacuoles, resembling grey eosinophils. To further characterize these cells, peripheral blood smears from the patient and a canine control with eosinophilia were stained for alkaline phosphatase (AP), peroxidase, and esterase activities, and with Luxol fast blue (LFB). Histopathologic sections of the nasal mass were stained with LFB and immunohistochemically for tryptase. On blood smears, the cytoplasm of the suspected grey eosinophils stained for AP and granules stained with LFB confirmed that there was an eosinophilic lineage. Peroxidase staining was weak, and esterase staining was absent. On histopathologic sections from the nasal mass, the segmented leukocytes contained LFB-staining granules, indicating an eosinophilic infiltrate was present. Neoplastic cells expressed tryptase, which confirms a mast cell lineage. Our findings suggest that grey eosinophils might be under-recognized and interpreted incorrectly as toxic neutrophils. This report expands the canine breeds in which these eosinophils have been identified.

The Spectrum of Hypereosinophilia and Associated Clonal Disorders - A Real-World Data Based on Combined Retrospective and Prospective Analysis from a Tropical Setting

OBJECTIVE

To determine the frequency, etiological spectrum and treatment outcome of hypereosinophilia (HE) and hypereosinophilic syndromes (HES) in a tropical setting.

METHODS

A retrospective analysis of hospital data of five years (January 2009 to December 2013) and a comprehensive prospective evaluation of patients presenting with HE/HES over a period of 33 months (January 2014 to September 2016) was performed.

RESULTS

HE/HES was diagnosed in a total of 125 patients during the study period with an estimated prevalence of 0.5-1 case per 100,000 population in our hospital settings. 41 patients were excluded from the final analysis due to lack of sufficient data. Infections, especially helminths were the commonest cause (34%) followed by primary/clonal HE/HES (24%) and reactive HE/HES secondary to various clonal disorders (14.3%). A lymphocytic variant of HES and FIP1L1-PDGFRA positive HES were diagnosed in 3.6% each. Imatinib-responsive BCR-ABL1 negative HE/HES constitute 7.1% in our patients. None of the clinical or routine laboratory features including the age of patients, duration of HE, presence or absence of organomegaly, hemoglobin levels, eosinophil %, absolute eosinophil count, total leukocyte count, platelet counts, serum IgE levels or presence of myelofibrosis could predict or exclude malignancy in patients with HE/HES. The absence of blasts in peripheral blood or the absence of >5% blasts in bone marrow does not exclude primary/clonal HES.

CONCLUSIONS

An underlying malignancy (Primary HE/HES and neoplasms leading to reactive HES; 35.7%) is diagnosed with nearly equal frequency compared to infections (34.5%) in tropical settings. There are no hematological or serological parameters, which can reliably be used to exclude an underlying malignancy, necessitating a thorough follow-up and comprehensive work-up in patients with HE/HES.