Search

Combined rearrangements of MYC and BCL2 are rare in precursor B-cell acute lymphoblastic leukemia (B-ALL). A 14-year-old boy presented with swelling of the knee and face. Imaging revealed diffuse infiltration of lacrimal glands, parotid glands along with the extensive epidural disease. Morphology and immunophenotype of knee joint aspirate were consistent with precursor B-ALL. Fluorescent in situ hybridization identified rearrangements of MYC and BCL2 genes. The disease was refractory to intensive treatment. The patient died of progressive disease. Precursor B-ALL with combined MYC and BCL2 rearrangements is rare, characterized by an aggressive clinical course, and has an inadequate response to standard therapeutic approaches.

Background and objectives We describe the third documented case of autochthonous human babesiosis in Canada and the second in a Canadian blood donor. Materials and methods Multiple laboratory investigations were carried out on the donor and the immunocompromised recipient of an associated, potentially infectious red blood cell product. Results The donor had not travelled except for outdoor exposure in south-eastern Manitoba, followed by illness and hospital admission. The donor had a notable parasitaemia, positive for Babesia microti using whole blood nucleic acid testing (NAT). The recipient was negative for B. microti by both serology and NAT. Conclusion There was no evidence of transfusion-transmitted babesiosis.

Extramedullary leukemia in pediatric acute myeloid leukemia can manifest as a myeloid sarcoma (MS), also known as granulocytic sarcoma or chloroma, in a variety of sites, or as leukemic blasts in the cerebrospinal fluid. Isolated MS of the central nervous system is rare. We report a case of acute myeloid leukemia with central nervous system-MS presenting as a posterior fossa mass mimicking a primary intracranial tumor.

An isolated epidural mass is a rare presentation of childhood B-acute lymphoblastic leukemia with an estimated incidence of 0.4%. Of the cases reported in the literature, the majority involve adults presenting with spinal cord compression and/or systemic evidence of disease. We describe a young child presenting with pain leading to a refusal to weight-bear secondary to a sacral epidural mass. A biopsy of the sacral lesion confirmed the diagnosis of B-acute lymphoblastic leukemia. Unique to this case is the young age of the child and the lack of spinal cord compression.

INTRODUCTION Isolated Myeloid sarcoma (MS) of the central nervous system (CNS-MS) is a very rare presentation of Acute Myeloid Leukemia (AML). A 10-year-old boy with a two-week history of intermittent headaches was referred to the emergency department (ED) by an optometrist for evaluation of bilateral papilledema. Physical examination in the ED confirmed the presence of papilledema with no other abnormal neurologic findings. Emergent MRI of the brain showed an avidly homogeneously enhancing extra-axial dural based mass in the right posterior fossa measuring 4.8 cm (AP) x 3.2 cm (CC) x 4.6cm (T), with significant mass effect and peri-tumoral vasogenic edema. Neuro-surgery consultation was obtained and complete blood count (CBC) was normal except for the presence of 13% blasts with occasional Auer rods seen on the peripheral blood smear. Bone marrow aspirate demonstrated 56% myeloblasts; A diagnosis of AML with CNS-MS (CNS-3c) was made and the initial lumbar puncture (LP) was deferred due to the risk of CNS herniation. Induction chemotherapy was initiated as per protocol. A CT scan done two weeks later showed complete resolution of the intracranial mass. DISCUSSION The incidental finding of papilledema, with imaging to investigate the intracranial pathology revealed a large posterior fossa mass in our patient. However, the atypical features of the mass (dural based extra-axial location; extensive infiltration into adjacent structures) and the finding of blasts with Auer rods in peripheral blood helped us to diagnose CNS-MS, and avoided an extensive neurosurgical procedure and a delay in definitive therapy. Our patient had a normal CBC and the review of the peripheral blood film by an experienced Hematologist was very crucial in making a clinical diagnosis of MS. CONCLUSION Myeloid sarcomas should be considered in the differential diagnosis of an intracranial mass, particularly when accompanied by abnormal findings in the CBC.

Key PointsBrain involvement, although rare, can occur in HCL. The combination of cladribine and rituximab is a highly effective treatment of HCL with brain involvement.

Background Pentraxin 3 (PTX3) is a multifunctional molecule that plays a nonredundant role at the crossroads between pathogen clearance, innate immune system, matrix deposition, female fertility, and vascular biology. It is produced at sites of infection and inflammation by both structural and inflammatory cells. However, its role in allergen-induced inflammation remains to be tested. Objective We sought to determine the effect of Ptx3 deletion on ovalbumin (OVA)–induced allergic inflammation in a murine model of asthma. Methods Bronchoalveolar lavage fluid was collected from patients with severe asthma and healthy subjects, and the level of PTX3 was determined by using ELISA. Ptx3 +/+ and Ptx3 −/− mice were sensitized and challenged with OVA and bronchoalveolar lavage fluid, and the lungs were collected for assessing inflammation. Lung tissue inflammation and mucus production were assessed by means of flow cytometry and hematoxylin and eosin and periodic acid-Schiff staining, respectively. flexiVent was used to determine airway resistance to methacholine in these mice. Results Here we report that mice with severe asthma and OVA-sensitized/challenged mice had increased PTX3 levels in the lungs compared with healthy control mice. Mice lacking PTX3 have exaggerated neutrophilic/eosinophilic lung inflammation, mucus production, and airway hyperresponsiveness in an experimental model of OVA-induced asthma. Furthermore, OVA-exposed lung Ptx3 −/− CD4 T cells exhibit an increased production of IL-17A, an effect that is accompanied by an increased signal transducer and activator of transcription 3 phosphorylation, reduced IL-2 production, and enhanced activation and survival. Also, we observed an increase in numbers of IL-6– and IL-23–producing dendritic cells in OVA-exposed Ptx3 −/− mice compared with those in wild-type control mice. Conclusion Altogether, PTX3 deficiency results in augmented airway hyperresponsiveness, mucus production, and IL-17A–dominant pulmonary inflammation, suggesting a regulatory role of PTX3 in the development of allergic inflammation.