Multicenter prospective study of children with sickle cell disease: radiographic and psychometric correlation.

After obtaining familial informed consent, between January 1996 and July 1997, 173 children (5 to 15 years old) with sickle cell disease were enrolled in a prospective multicenter study using blood screening, transcranial Doppler ultrasonography (n = 143), cerebral magnetic resonance imaging (n = 144), and neuropsychologic performance evaluation (n = 156) (Wechsler Intelligence tests WISC-III, WIPPSI-R), which were also performed in 76 sibling controls (5 to 15 years old). Among the 173 patients with sickle cell disease (155 homozygous for hemoglobin SS, 8 sickle cell beta0 thalassemia, 3 sickle cell beta+ thalassemia, 7 sickle cell hemoglobin C disease SC), 12 (6.9%) had a history of overt stroke, and the incidence of abnormal transcranial Doppler ultrasonography (defined as mean middle cerebral artery velocity > 200 cm/sec or absent) was 8.4% in the overall study population and 9.6% in patients with homozygous sickle cell anemia The silent stroke rate was 15%. Significantly impaired cognitive functioning was observed in sickle cell disease patients with a history of stroke (Performance IQ and Full Scale IQ), but also in patients with silent strokes (Similarities, Vocabulary, and Verbal Comprehension). However, infarcts on magnetic resonance imaging were not the only factors of cognitive deficit: Verbal IQ, Performance IQ, and Full Scale IQ were strongly impaired in patients with severe chronic anemia (hematocrit < or = 20%) and in those with thrombocytosis (platelets > 500 x 10(9)/L). Multivariate logistic regression analysis showed that abnormal magnetic resonance imaging (odds ratio [OR] = 2.76) (P = .047), hematocrit < or =20% (OR = 5.85) (P = .005), and platelets > 500 x 10(9)/L (OR = 3.99) (P = .004) were independent factors of cognitive deficiency (Full Scale IQ < 75) in sickle cell disease patients. The unfavorable effect of low hematocrit has already been suggested, but this is the first report concerning an effect of thrombocytosis and showing that silent stroke alone is not a factor of cognitive deficit when not associated with low hematocrit or thrombocytosis. The effect of hydroxyurea, which is known to increase hematocrit and decrease platelet count, on cognitive functioning of sickle cell patients should be evaluated prospectively.

[Renal stenosis in hypertensive children. Doppler/arteriographic correlation]. / Sténoses rénales chez les enfants hypertendus. Corrélation Doppler/arteriographie.

To evaluate the reliability of Doppler-ultrasonography in identifying children with renal artery stenosis among those with hypertension, we compared Doppler ultrasonography results in 29 hypertensive children (mean age: 8.3 +/- 4.7 years) with angiography. Doppler-ultrasonography and arteriography were performed within a period less than two months. First, we established normal values in 40 normotensive children (mean age: 8.4 +/- 4.5 years). The diagnosis of renal artery stenosis was settled when maximal systolic velocities where > or = to 1.70 m.s-1. Peak systolic velocities values of Doppler-ultrasonography were significantly higher in patients with proven angiographic renal artery stenosis (3.56 +/- 0.70 m.s-1) than in hypertensive patients with normal renal arteries at angiography (1.02 +/- 0.29 m.s-1, p < 0.0001), and than in normotensive healthy children (1.05 +/- 0.33 m.s-1, p < 0.0001). We observed 3 false negative and 2 false positive diagnoses with Doppler-ultrasonography. Of the 3 false negatives, one had a stenosis on a right and posterior segmental artery and the other had bilateral and multiply intra-renal artery stenosis with few hemodynamic significance. The 2 false positives were due to a sinuous main renal artery and to a technical mistake, respectively. In another patient, Doppler-ultrasonography revealed a tight main renal artery stenosis, not detected by arteriography. Renal artery stenosis was subsequently confirmed by a second arteriography. Our results showed a sensitivity of 88%, a specificity of 93%, a positive predictive value of 92% and a negative predictive value of 89%, demonstrating the reliability of Doppler-ultrasonography for the diagnosis of renal artery stenosis in hypertensive children. With the use of a rigorous methodology and the increasing experience of the operators, diagnostic errors of renal artery stenosis are currently avoidable. Nevertheless, it is not excluded that intra-renal artery stenosis with few hemodynamic significance might be missed by Doppler-ultrasonography.

Value of Doppler ultrasound for the diagnosis of renal artery stenosis in children.

To evaluate the reliability of Doppler ultrasonography (US) in identifying children with renal artery stenosis (RAS) among those with hypertension, we compared Doppler US results in 22 hypertensive children (mean age 8.9 +/- 4.3 years), with (13 cases) and without RAS at angiography, and in 33 normotensive children (mean age 8.8 +/- 4.7 years). We observed 2 false-negatives and 2 false-positives with Doppler US. Of the 2 false-negative diagnoses, I had RAS on an accessory renal artery located behind a normal upper polar artery and the other was observed in a patient with bilateral multiple stenosis of the very distal segments of renal arteries. The 2 false-positive diagnoses were due to sinuous left renal artery and to technical reasons, respectively. In another patient, Doppler US showed a tight RAS, while arteriography was normal. RAS was subsequently confirmed by a second arteriography. Peak systolic velocity values of Doppler US were significantly higher in patients with proven angiographic RAS (3.44 +/- 0.66 m/s) than in hypertensive patients with normal renal arteries at angiography (0.99 +/- 0.35 m/s, P < 0.0001) and normotensive healthy children (1.04 +/- 0.23 m/s, P < 0.0001). With the use of multiple views, and the experience acquired with practice, false-negatives or false-positives due to the geometry of the renal artery can be avoided. Nevertheless, very distal stenosis can be missed by Doppler US.

[Fetal echocardiography. The normal heart]. / Echocardiographie foetale. Le coeur normal.

At 20 weeks amenorrhoea, it is currently possible to determine with echocardiography whether a fetal heart, which then weighs approximately 400g with a diameter of 15 mm, is normal or not. The incidence of cardiac malformations has been estimated at 8 per 1000 fetuses. Fetal factors including retarded growth, hydramnios and arrhythmia and maternal factors including rubeola, diabetes, systemic lupus erythematosus, Rhesus incompatibility and drugs increase fetal risk. In certain cardiopathies such as aortic stenosis, coarctation, malformation of the mitral valve or left ventricle hypoplasia, the risk of recurrence in a second fetus is greatly increased. With 2D echocardiography, the apical section of the four heart cavities orients the heart in the thorax, identifies the atria and ventricles and visualizes valve movement. The origin of the aorta and the kinetics of the mitral and aortic valves are studied on the para-sternal section. TM mode reproduces the P-QRS sequence thus allowing a measurement of heart rate, the thicknesses of heart walls and septa and identifies conduction disorders. The transvalvular systolic pressures can be measured with Doppler echocardiography and pulsed Doppler quantifies blood flow through the different heart structures. Precision can be increased with colour coding. A complete echocardiography of the fetal heart should be an integral part of all examinations of fetal morphology. Usually performed between 22 and 32 weeks of amenorrhoea, echocardiography of the fetal heart requires a perfect understanding of two-dimensional Doppler modes and of three-dimensional representation of heart anatomy.

Percutaneous treatment of hydatid cysts (Echinococcus granulosus).

A new method called PAIR (Puncture-Aspiration of cyst contents--Injection of hypertonic saline solution--Reaspiration) was used as a percutaneous treatment of hydatid cysts. In 37 patients, 120 cysts were punctured. All patients had not been considered surgical candidates. The cysts were localized in the liver, peritoneum, spleen, kidneys, muscles, and bones. In 70% of patients, good results were obtained. Recurrence occurred in 5 of 120 cysts, all at the beginning of our experience when a low concentration of sodium chloride solution was injected. Moderate allergic reactions occurred during seven cyst aspirations. No anaphylactic shock, sudden deaths or dissemination of cyst contents were observed.