Catherine Ross

Therapeutic effect of angiostatin gene transfer in a murine model of endometriosis.

Endometriosis, the growth of ectopic endometrial tissue, is a chronic recurrent disease affecting 10% of the female population causing dyspareunia, pelvic pain, dysmenorrhea, and infertility. Suppression of ovarian activity is the cornerstone of medical therapy with limited benefit and severe adverse effects. Angiogenesis plays a major role in the development of endometriosis suggesting that anti-angiogenic therapy would offer a new therapeutic approach. We report successful treatment of endometriosis in estrogen-supplemented ovariectomized mice by transient overexpression (6 to 10 days of duration) of the gene for a natural angiogenesis inhibitor angiostatin, delivered to the peritoneum by a replication-deficient adenovirus vector (AdAngiostatin). Established endometriosis was eradicated in 14 of 14 AdAngiostatin-treated animals, whereas 11 of 13 control animals showed full disease development. Administered to normal cycling mice for the same transient period, AdAngiostatin caused impaired ovarian function with suppressed corpus luteum development, decreased production of estradiol and progesterone, decreased ovarian and uterine weight, and increased body weight. AdAngiostatin treatment lowered the levels of sex steroids but did not induce total castration. Gene therapy with angiogenic inhibitors is a highly effective treatment for endometriosis, even in a host with preserved estrogen levels. However, local or targeted delivery of the gene must be considered to avoid prolonged systemic effects and impaired ovarian function.

Telepathology for routine light microscopic and frozen section diagnosis.

Telepathology (TP) uses telecommunication linkages to electronically capture, store, retrieve, and transmit images to distant sites. We assessed the feasibility of a dynamic real-time TP system for light microscopic (LM) diagnosis of anatomic pathology specimens, including frozen sections. Six pathologists, in 2 separate periods, read a set of 160 retrospectively retrieved slides (80 of which were frozen sections) by TP and LM. Reading times were recorded. Diagnoses were compared with the reference diagnosis (established by a group of 5 independent pathologists) and graded on a scale of 0 to 2 (2, correct; 1, incorrect but no clinical impact; 0, incorrect with clinical impact). Overall, LM was more accurate than TP compared with the reference diagnosis (score, 1.68 vs 1.54). There was no difference in accuracy between frozen section and paraffin-embedded tissue. Intraobserver agreement ranged from 82.5% to 88.2%. The average reading time was 6.0 minutes for TP and 1.4 minutes for LM. During the study, reading time decreased for TP but not for LM. These results show that despite marginally lower accuracy and longer reading times, TP isfeasible for routine light microscopic diagnosis, including frozen sections.

Synchronously diagnosed lymph nodal collision tumor of malignant melanoma and chonic lymphocytic leukemia/small lymphocytic lymphoma: case report

Synchronous composite tumors have been described but are uncommon. Moreover, simultaneous occurrence of synchronous tumors in the same tissue or organ is even less common. We report a case of chronic lymphocytic leukemia (CLL)/small lymphocytic lymphoma and malignant melanoma (MM) occurring synchronously in the same lymph node. Several cases of an association between cutaneous malignancies and lymphoproliferative disorders have been reported. Some of which included CLL and MM, occurring in the same patient often CLL after MM. The risk of having CLL after MM has been reported to be increased. Various genetic and environmental etiologies have been postulated, but have as yet not been proven. To our knowledge this is the first time that synchronous occurrence of these two malignant processes in the same tissue is described. In this case it is important that the melanoma was recognized in the excised lymph node, as this finding had much more critical treatment and long term survival consequences.

Congenital inflammatory myopathy: A demonstrative case and proposed diagnostic classification

There have been few reports of congenital inflammatory myopathy in the literature, and most of these have been associated with congenital muscular dystrophy. We review the literature and present a case with electromyographic and muscle biopsy evidence of congenital inflammatory myopathy with onset in the perinatal period and no evidence of a congenital muscular dystrophy. There was evidence of subjective improvement following corticosteroid administration (∼ mg/kg per day) with a concomitant normalization of the serum creatine kinase activity. Of particular interest in the case was the history of maternal infection, suggesting a possible postinfectious molecular mimicry as the etiology of the muscle inflammation. This case suggests that a rare form of congenital inflammatory myopathy does exist that is not associated with a congenital muscular dystrophy. A preliminary classification scheme is proposed to separate true congenital cases from those acquired after birth and those cases associated with congenital dystrophy.

A blinded study of bone marrow examinations in patients with primary immune thrombocytopenia

The role of bone marrow examinations in patients with primary immune thrombocytopenia (ITP) is uncertain. The objectives of this study were to determine the inter‐rater reliability of bone marrow examinations and to identify distinguishing morphological features of ITP bone marrows under controlled conditions.

Lymphoproliferative Lesions in the Setting of HIV Infection: A Five-Year Retrospective Case Series and Review

A wide variety of noninfectious lesions have been identified in association with HIV infection. Many hematolymphoid lesions are possible in this patient group, both reactive and neoplastic. Epidemiologic data suggests that lymphoid malignancies are among the most common neoplasms in patients with HIV. We present a selective case series assembled over a 5-year period from the relatively low HIV-prevalence Hamilton Regional Laboratory Medicine Program (HRLMP), a tertiary care referral centre in Southern Ontario. This series serves to demonstrate the wide variety of lymphoid lesions that may be encountered in patients with HIV. In addition to outlining the pathologic work-up necessary in these cases, we discuss characteristics that distinguish the HIV-associated lesions from the pathobiologically similar non-HIV-associated lymphoid lesions.

Coagulopathy in a patient with nephrotic syndrome

A 55-year-old Caucasian woman presented with a 5week history of increasing lower limb edema associated with a two-pound daily weight gain. She was feeling well otherwise; she denied shortness of breath, chest discomfort, recurrent headaches, myalgia, arthlagia, or constitutional symptoms. She had respiratory infection 4 months before, but the infection has resolved. The patient presented with peripheral edema. The differential diagnosis includes right-sided heart failure, liver cirrhosis, nephrotic syndrome, drug-induced edema, and lymphoedema. Her preceding upper respiratory tract infection suggests postinfectious cardiac or renal pathology. The patient did not have any prior bleeding episode. The medical history was significant for Graves’ disease treated with radioactive iodine ablation. The only medication was daily thyroid supplementation. She was married and had two uncomplicated pregnancies. She was a lifelong nonsmoker. She denied any alcohol intake or illicit drug use. She was a pharmacist without any known exposure to toxic chemicals. On examination her vital signs were normal. She was not in any distress. Examination of her legs revealed bilateral pitting peripheral edema up to the knee level. There was no jaundice, lymphadenopathy, or bleeding sign. Her cardiac examination was normal and her jugular venous pressure (JVP) was not elevated. Respiratory examination was normal with no crackles on auscultation. Abdominal examination revealed no palpable hepatosplenomegaly or ascites. The fact that this patient was not on any medication other than long term thyroid supplement makes druginduced edema unlikely. The finding of normal JVP on clinical examination is against the diagnosis of heart failure. Lymphedema is typically nonpitting. Thus, the most likely differential diagnosis includes nephrotic syndrome and early liver cirrhosis. Patient’s hemoglobin level was 19.0 g/dL (normal 11.5– 16.5 g/L), platelet count 305,000/mm (normal 150,000– 400,000/mm). The blood urea nitrogen was 14.4 mg/dL (normal 7.0–18.0 mg/dL), creatinine 0.93 mg/dL (normal <1.5 mg/dL), albumin 2.0 g/dL (normal 3.5–5.5 g/dL), cholesterol 587 mg/dL (normal <200 mg/dL), and triglyceride 447.1 mg/dL (normal <160 mg/dL). The results of liver function tests were normal. Urinalysis revealed 11 blood, 31 protein, and granular casts. Twenty-four hour urine protein excretion was 15,000 mg/d. The combination of heavy proteinuria, minimal hematuria, hypoalbuminemia, and hypercholesterolemia suggests nephrotic syndrome. Nephrotic syndrome may be associated with primary kidney disease, such as minimal change disease, focal segmental glomerulosclerosis, and membranous nephropathy. Systemic diseases including diabetes mellitus, systemic lupus erythematosus, amyloidosis, or Fabry’s disease also cause nephrotic syndrome. International normalized ratio (INR) was increased to 2.6 and activated partial thromboplastin time (aPTT) was prolonged to 68 s but thrombin clotting time was normal. Clauss fibrinogen level was slightly elevated at 480 mg/dL (normal range 200–400 mg/dL). D-dimer level was not elevated. In general, patients with nephrotic syndrome are in a hypercoagulable state because of urinary loss of antithrombin III and enhanced platelet reactivity, but this patient’s coagulation tests were paradoxically prolonged although there was no bleeding symptom. Simultaneous prolongation of both INR and aPTT suggests common coagulation pathway abnormalities like liver dysfunction, vitamin K deficiency, disseminated intravascular coagulopathy (DIC), primary fibrinolysis or post-thrombolytic therapy. However, the normal thrombin clotting time and borderline high fibrinogen level make abnormalities in the conversion pathway of fibrinogen to fibrin less likely. Normal fibrinogen and D-dimer level are atypical for DIC. A deficiency of multiple coagulation factors in both intrinsic and extrinsic coagulation pathways commonly occurs in vitamin K deficiency or hepatic dysfunction. However, 48 hr after administration of 5 mg oral vitamin K, the coagulation indices remained prolonged with an INR at 2.6 and aPTT at 63 s. To further define the causes of coagulopathy, clotting factor levels were assayed individually. Factor II level was high at 166%, factor VII 179%, but factor VIII:C was low at 7%, factor X 3%, whereas factor XII level was borderline low at 47%. (Normal range of these clotting factors was 50–150%). Although acquired factor XII deficiency has been reported in patients with nephrotic syndrome [1], deficiency of multiple coagulation factors suggests acquired conditions, either due to insufficient production or excessive consumption. Coagulation factors II, V, VII, IX, X, XI, and XII are synthesized in the liver, and in addition factor VIII also

Antibody binding to megakaryocytes in vivo in patients with immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an autoimmune bleeding disorder caused by increased platelet destruction and impaired platelet production. Antibody binding to megakaryocytes may occur in ITP, but in vivo evidence of this phenomenon is lacking.

Megakaryocyte apoptosis in immune thrombocytopenia

Abstract The mechanisms of platelet underproduction in immune thrombocytopenia (ITP) remain unknown. While the number of megakaryocytes is normal or increased in ITP bone marrow, further studies of megakaryocyte integrity are needed. Megakaryocytes are responsible for the production of platelets in the bone marrow, and they are possible targets of immune-mediated injury in ITP. Since the biological process of megakaryocyte apoptosis impacts platelet production, we investigated megakaryocyte DNA fragmentation as a marker of apoptosis from ITP bone marrow biopsies. Archived bone marrow biopsy specimens from ITP patients, bone marrow specimens from controls with normal platelet counts, and bone marrow specimens from thrombocytopenic controls with myelodysplastic syndrome (MDS) were evaluated. Sections were stained with anti-CD61 for megakaryocyte enumeration, and terminal deoxynucleotidyl transferase dUTP nick-end labeling was used as an apoptotic indicator. In ITP patients, megakaryocyte apoptosis was reduced compared to nonthrombocytopenic controls. Megakaryocyte apoptosis was similarly reduced in thrombocytopenic patients with MDS. These results suggest a link between megakaryocyte apoptosis and platelet production.