G C Del Vecchio

Ischemic stroke in children treated for acute lymphoblastic leukemia: a retrospective study.

The clinical and diagnostic findings and the factors influencing the neurologic and radiologic outcome of symptomatic ischemic stroke were evaluated in a group of 2,318 children with acute lymphoblastic leukemia (ALL) treated according to the AIEOP (Italian Association of Pediatric Hematology and Oncology) study protocols. In this multicentric retrospective study, a questionnaire was sent to each of the 43 AIEOP centers participating in the study. The questionnaire was designed to obtain information on the number, type, and time of occurrence of ischemic strokes, biologic and immunologic features of each case, as well as clinical data of the recruited patients. A prevalence of 0.47% was found. All ischemic strokes were sinovenous thrombosis (SVT). The most common neurologic presentations were diffuse neurologic signs and seizures. MRI with or without venography revealed SVT in 100% of cases; superficial SVT was diagnosed in the majority of cases. Antithrombotic drugs, in particular unfractioned heparin and low-molecular-weight heparin, were administered without bleeding complications. This series shows an excellent long-term neurologic outcome in children with SVT. However, a complete radiologic resolution was found in only 54% of cases; the involvement of deep cerebral venous sinuses was associated with an unfavorable imaging outcome.

HHT in childhood: screening for special patients.

Hereditary hemorrhagic telangiectasia (HHT) or the Rendu-Osler-Weber disease is a systemic fibrovascular autosomal dominant dysplasia, recognised when three of the following four clinical manifestations are present, according to the proposal of Shovlin.: recurrent nosebleeds, lelangiectasias of the skin, visceral lesions, and positive family history. HHT is often difficult to diagnose on the basis of history and physical examination alone, especially in infants and children. The signs and symptoms of HHT are nonspecific and are extremely variable within families. Given the frequent occurrence of clinically silent lesions in lung and brain arteriovenous malformations which can result in morbidity or death, much consideration should be given to screening patients with HHT for asymptomatic fistulae and to their treating once they are discovered. Presymptomatic interventions in such cases may substantially affect the outcome. It may be possible to state that lesions of HHT arise early in life, but do not reach sufficient size to cause symptoms until the second decade. Furthermore, as clinical manifestations often occur later in life, the development and the implementation of a molecular diagnosis will allow the identification of subjects with no evident signs of the disease but carrying the familial mutation. This is fundamental in order to establish reliable screening protocols for the prevention and cure of the disease and, to determine the presence of family members with no disease-associated mutation, who do not require further clinical screening.

SUCCESSFUL TREATMENT OF PURE RED CELL APLASIA IN A CHILD BY HIGH DOSE INTRAVENOUS IMMUNOGLOBULIN. 94

The term pure red cell aplasia (PRCA) indicates a heterogeneous group of congenital or acquired blood disorders characterized by anemia, reticulocytopenia, and paucity of erythroid precursors in an otherwise normally cellular bone marrow. Some forms of PRCA appear to have an immune-mediated pathogenesis; both humoral inhibitors and T-cell mediated inhibition of erythropoiesis have been described. We describe the case of a child with immune-mediated PRCA who was successfully treated by high intravenous doses of gamma-globulin.

APC RESISTANCE IN THALASSEMIC PATIENTS: AN UNDER-LYING CAUSE OF THROMBOSIS. 167

Objectives of the study: Primary, the evaluation of prevalence of resistance to activated protein C (APCR) in thalassemic patients; secondary, the study of prevalence of thrombosis in a group of polytransfused thalassemic patients.

8 NUCLEAR NAGNETIC RESONANCE AND IRON OVERLOAD IN THALASSEMIA MAIOR AFTER BONE MARROW TRANSPLANTATION

Nuclear magnetic resonance (NHR) imaging is a new and noninvasive technique to detect tissue iron. In fact the signal intensity on spin echo images is as low as tissue iron load is high. We used this technique to assess tissue iron load in 10 β-thalassaeaic maior patients (mean age 11 ± 4.8 years) after bone marrow transplantation (BMT); the follow-up ranged between 10 and 54 months (mean 27.3 months) from transplant. In ail patients a significant correlation has been observed between the summation of signals given out from all the organs examined (liver, spleen and pancreas) with iron overload versus serum ferritin levels (r . 0.64; p < 0.05). Signals obtained from each organ were not correlated with serum ferritin levels, but the only exception was the signal obtained from liver (r = 0.69; p < 0.05).We conclude that NMR is of great diagnostic validity for the evaluation of iron load of each organ in patients with β-thalassemia subjected to BUT, while serum ferritin levels are related only with total body iron overload. At last these Findings lead us to speculate about the need in these subjects to continue a chelation therapy or to undergo periodic phlebotomy.