Acute promyelocytic leukaemia (APL) in a patient with Crohn's disease and exposure to infliximab: a rare clinical presentation and review of the literature

With the introduction of potent immunosuppressive and chemotherapeutic medications for various diseases, there is an increased incidence of therapy-related myeloid neoplasms. They are the result of mutational rearrangement and historically, have a grave prognosis compared with de novo myeloid neoplasms. We did a short review on various types of myeloid leukaemias reported after therapy with antitumour necrosis factor and also report, to the best of our knowledge, one among the very few cases of therapy-related acute promyelocytic leukaemia in a patient on infliximab therapy for refractory Crohn's disease. The patient responded well to the traditional treatment and is in complete remission for more than 5 years.

Glanzmann's thrombasthenia: report of a case and review of the literature

Glanzmann's thrombasthenia is a rare congenital bleeding disorder. Patients usually present with mucocutaneous bleeding and excessive bleeding associated with trauma and/or surgery. Patients have an increased bleeding time and a normal platelet count with abnormal platelet function assays. Genetically, Glanzmann's thrombasthenia is associated with mutations in the genes which encode for glycoproteins, GPIIb or GPIIIa. Defects in these genes lead to a lack of or highly reduced expression of the glycoprotein complex (GPIIb/GPIIIa), resulting in platelet dysfunction. Bleeding is managed by platelet transfusions. Bone marrow transplants have been used successfully in rare cases. With proper supportive care Glanzmann's thrombasthenia has a very good prognosis.

Human type II pneumocyte chemotactic responses to CXCR3 activation are mediated by splice variant A

Chemokine receptors control several fundamental cellular processes in both hematopoietic and structural cells, including directed cell movement, i.e., chemotaxis, cell differentiation, and proliferation. We have previously demonstrated that CXCR3, the chemokine receptor expressed by Th1/Tc1 inflammatory cells present in the lung, is also expressed by human airway epithelial cells. In airway epithelial cells, activation of CXCR3 induces airway epithelial cell movement and proliferation, processes that underlie lung repair. The present study examined the expression and function of CXCR3 in human alveolar type II pneumocytes, whose destruction causes emphysema. CXCR3 was present in human fetal and adult type II pneumocytes as assessed by immunocytochemistry, immunohistochemistry, and Western blotting. CXCR3-A and -B splice variant mRNA was present constitutively in cultured type II cells, but levels of CXCR3-B greatly exceeded CXCR3-A mRNA. In cultured type II cells, I-TAC, IP-10, and Mig induced chemotaxis. Overexpression of CXCR3-A in the A549 pneumocyte cell line produced robust chemotactic responses to I-TAC and IP-10. In contrast, I-TAC did not induce chemotactic responses in CXCR3-B and mock-transfected cells. Finally, I-TAC increased cytosolic Ca2+ and activated the extracellular signal-regulated kinase, p38, and phosphatidylinositol 3-kinase (PI 3-kinase)/protein kinase B kinases only in CXCR3-A-transfected cells. These data indicate that the CXCR3 receptor is expressed by human type II pneumocytes, and the CXCR3-A splice variant mediates chemotactic responses possibly through Ca2+ activation of both mitogen-activated protein kinase and PI 3-kinase signaling pathways. Expression of CXCR3 in alveolar epithelial cells may be important in pneumocyte repair from injury.

Unique pattern of nuclear TdT immunofluorescence distinguishes normal precursor B cells (Hematogones) from lymphoblasts of precursor B-lymphoblastic leukemia

Normal precursor B cells or hematogones share morphologic and immunophenotypic similarities with lymphoblasts of precursor B-lymphoblastic leukemia. The numbers are often increased and difficult to distinguish in many patients following chemotherapy for precursor B-lymphoblastic leukemia. The purpose of this study was to establish a unique method for differentiating hematogones from lymphoblasts by evaluating the immunofluorescence pattern of nuclear terminal deoxynucleotidyl transferase (TdT) staining in 29 cases of TdT+ acute leukemia and 20 cases with increased numbers of hematogones. All 29 cases of TdT+ acute leukemia demonstrated a finely granular pattern of TdT immunofluorescence that was uniformly distributed in the nucleus, whereas all 20 cases with increased hematogones demonstrated a coarsely granular or speckled pattern of TdT immunofluorescence, which often intensely aligns the nuclear membrane. The nuclear pattern of immunofluorescence using antibodies to TdT is an effective method for distinguishing hematogones from leukemic blasts.

Polymorphous hemangioendothelioma in a child with acquired immunodeficiency syndrome (AIDS)

Polymorphous hemangioendotheliomas (PH) are rare and borderline malignant tumors that are among the wide range of vascular tumors. We report here a 13-year-old male presenting with a history of weight loss, opportunistic infections, and lymphadenopathy. He was determined to be HIV positive and to have acquired immunodeficiency syndrome (AIDS). A biopsy of a femoral node was diagnostic of PH. His systemic lymphadenopathy appeared to resolve with anti-retroviral therapy. This tumor should be considered within the differential diagnoses of pediatric and immunocompromised patients.

Hermansky-pudlak syndrome: report of a case and review of the literature

Hermansky-Pudlak syndrome is a rare autosomal recessive disorder characterized by excessive bleeding post surgery. Here we reported such a case and reviewed the clinicopathological features and our current understanding of this rare congenital disorder.

Kimura disease

Kimura disease is a benign rare chronic inflammatory disorder of unknown etiology that involves the lymph nodes and subcutaneous tissue of the head and neck regions. Elevated serum immunoglobulin E levels and peripheral blood eosinophilia are also common. This disease is most common in middle-aged Asian men. Although the etiology is unknown, it most probably represents an aberrant chronic immune response. Treatment for Kimura disease includes surgical resection and regional or systemic steroid therapy. Cytotoxic therapy and radiation have also been utilized. The disease has an excellent prognosis, although it may recur locally.

A novel mutation in exon 5 of the ALAS2 gene results in X-linked sideroblastic anemia

BACKGROUND

Mutations in the erythroid-specific 5-aminolevulinate-synthase gene (ALAS2) have been identified in many cases of X-linked sideroblastic anemia (XLSA).

METHODS

A polymerase chain reaction-mediated restriction fragment length polymorphism (RFLP) assay was used.

RESULTS

A G527T point mutation was identified. This resulted in a substitution of tyrosine for asparagine at residue 159 (D159Y). This mutation was also identified in the mother of the two probands. Mutations in all three individuals were confirmed by DNA sequencing analysis.

CONCLUSIONS

We identified a missense mutation in exon 5 of the ALAS2 gene in two brothers of a consanguineous marriage, who were clinically pyridoxine-responsive.

Extramedullary myeloid cell tumor of the urinary bladder in a patient with myelodysplastic syndrome

We report a case of extramedullary myeloid cell tumor of the urinary bladder in an elderly male with a three year history of myelodysplastic syndrome (refractory anemia with excess blasts), noninvasive papillary transitional cell carcinoma of the urinary bladder, and in situ transitional cell carcinoma of the left ureter. Light microscopy demonstrated a poorly differentiated neoplasm composed of medium to large cells with eosinophilic cytoplasm. The tumor cells showed immunohistochemical expression of myeloperoxidase, lysozyme, CD15, CD68 and CD43. Bone marrow examination following cystectomy demonstrated refractory anemia with excess blasts (6-10%) and a normal karyotype. Cytogenetics, approximately 1 year after cystectomy, demonstrated a deletion of the short arm of chromosome number 12. Four years after presentation, the patient succumbed to pulmonary aspergillosis.