Paul R. Yenson

A phase‐II sequential case‐series study of all patients presenting to four plasma exchange centres with presumed relapsed/refractory thrombotic thrombocytopenic purpura treated with rituximab

The primary objective of this phase II study was to evaluate the efficacy of rituximab in the management of adult patients with physician‐diagnosed presumed thrombotic thrombocytopenic purpura (TTP); relapsed or refractory. We conducted a multicentre study in four Canadian hospital‐based apheresis units. Forty patients with presumed TTP (20 refractory and 20 relapsing) were sequentially enrolled and all received rituximab in a standardized manner. A complete response was documented in 14 of 19 refractory patients by week 8 and 15/16 were alive and in remission at 52 weeks (one patient was lost to follow‐up, one was a non‐responder, and three died). Among relapsing patients, 16/18 had a complete response at week 8 and 18/18 at week 52 (one patient lost to follow‐up and one withdrew). At 1 year, all relapsing and 85% of refractory patients survived. Of 38/40 patients who had ADMATS13 testing at study entry, 13/19 refractory and 10/19 relapsing patients had ADAMTS13 < 10% (typical TTP); whereas 6/19 refractory and 9/19 relapsing cases had ADAMTS13 > 10% (other thrombotic microangiopathy; TMA). Refractory‐typical TTP in contrast to refractory‐other TMA and all relapsing patients treated with plasma exchange and rituximab, were less likely to be responsive and more likely to die or relapse.

Diagnosis and management of iliofemoral deep vein thrombosis: clinical practice guideline

Venous thromboembolism, presenting as deep vein thrombosis (DVT) or pulmonary embolism, affects over 35 000 Canadians each year.[1][1] It is associated with substantial morbidity, mortality and burden on the Canadian health care system, with one-month mortality rates estimated at 6% for DVT and 12%

A series of 4 cases of distinct keratopathy secondary to dysproteinemia: Immunotactoid keratopathy

OBJECTIVE To describe a series of 4 cases of immunotactoid keratopathy (ITK) secondary to monoclonal gammopathy. DESIGN Multicentre retrospective case series of 4 patients. PARTICIPANTS Eight eyes of 4 patients presenting to a cornea service with ITK. METHODS Retrospective case series of 4 patients referred between 2011 and 2013 for bilateral corneal opacities. Work-up including serum protein electrophoresis was performed, and slit-lamp photographs were obtained. RESULTS After investigation, diagnoses of ITK secondary to monoclonal gammopathy of unknown significance were established in 3 cases. In 1 patient, the diagnosis of monoclonal gammopathy of unknown significance was established prereferral. CONCLUSIONS ITK secondary to plasma cell disorders can clinically resemble a broad category of disease processes and must be considered when evaluating patients with bilateral peripheral stromal opacities. Our series validates previously proposed classification schemes for these opacities.

Microangiopathic haemolytic anaemia and hyposplenism in angiosarcoma

An 83-year-old man presented with an 18-month history of hyposplenic blood film features and progressive microangiopathic haemolytic anaemia for 6 months (top left). He had recently developed dyspnoea. Past history included melanoma and basal cell carcinoma. Bone marrow could not be aspirated. Touch preparations of a core biopsy specimen showed occasional large mononuclear cells (20–30 lm diameter) with variably vacuolated cytoplasm. The bone marrow was fibrotic and extensively infiltrated by spindle-shaped and polyhedral cells, focally forming vascular structures with red blood cells in them (bottom left), expressing CD31 (bottom right) and CD34, and lacking S100 and human herpesvirus 8, thus confirming the diagnosis of angiosarcoma. A computed tomography scan (top right) showed a normal sized spleen infiltrated by a multi-nodular conglomerate mass, haemoperitoneum adjacent to the liver and within the mesentery, and a cardiophrenic lymph node. The patient developed multiorgan failure and died within 2 weeks of his diagnosis. Thrombotic microangiopathy as a presenting feature of angiosarcoma is rarely described. Shearing of blood cells within the neoplastic blood vessels may contribute to this condition. Bone marrow involvement is rarely reported and usually represents disseminated disease.

Solvent-Detergent Plasma for the Treatment of Thrombotic Microangiopathies: A Canadian Tertiary Care Centre Experience

Solvent detergent-treated plasma (SDP) is a pathogen-inactivated blood plasma, which in comparison to frozen plasma is associated with lower rates of allergic reaction, transfusion-associated lung injury, and viral transmission. SDP has been available in Canada since 2012. Data on SDP use in Canada remains limited. We present a review of subjects receiving SDP at a large tertiary care centre primarily for thrombotic thrombocytopenic purpura and atypical hemolytic uremic syndrome, demonstrating the tolerability and safety of SDP.

Safety and feasibility of red cell exchange for sickle cell disease across Canada

We outline a case whereby RBCX was successfully provided over disparate geographical areas and time zones in Canada and overcame the logistical challenges of coordinating care across four different health care systems with the application of modern telecommunication technologies. We present this case as a model for other SCD providers and patients.