Antiplatelet drugs in secondary prevention after acute myocardial infarction.

Clopidogrel, a new ADP receptor antagonist, selectively and irreversibly inhibits ADP-induced platelet activation and aggregation thereby preventing atherothrombosis. Clopidogrel 75 mg o.d. and aspirin 325 mg o.d. were compared in the CAPRIE trial, a prospective international multicenter double-blind trial conducted in 19,185 high- risk patients with symptomatic atherosclerotic disease. Qualifying events for inclusion into the trial were ischemic stroke (IS) within the past six months, myocardial infarction (MI) within the past 35 days or peripheral arterial disease. Duration of treatment was one to three years. The primary efficacy end point was a composite cluster of IS, MI of vascular death. Overall, clopidogrel provided an 8.7% relative risk reduction (p = 0.043) in the occurrence of a first event of the cluster over and above aspirin and a favorable trend on each of the components of the primary end point. The greatest relative risk reduction was noted for prevention of MI (19.2%). In terms of number of events prevented per 1,000 patients and per year, clopidogrel is expected to prevent 24 major atherothrombotic events versus 19 with aspirin. Clopidogrel shows a favorable safety profile with fewer cases of gastrointestinal bleeding and better gastric tolerability.

[Bone demineralization and elevation of serum osteocalcin concentrations in young children with hyperthyroidism]. / Déminéralisation osseuse et elévation des concentrations sériques d'ostéocalcine chez les jeunes enfants atteints d'hyperthyroïdie.

Bone mineralization and serum osteocalcin level were evaluated in 15 children with Grave's disease. Two groups were constituted according to the presence (group I: n = 9) or absence (group II: n = 6) of a severe bone demineralization. A spontaneous fracture and a collapsed vertebra were found in one group I patient. Patients in group I were younger than in group II (8.3 +/- 4.9 vs 11.5 +/- 4.3 yrs). One patient in group II and six in group I were prepubertal with advanced bone age and increased growth velocity. Osteocalcin measurement (Oc) was performed in 10 patients (group I: n = 6; group II: n = 4) at the time of biological hyperthyroidism. The six patients with bone demineralization had elevated Oc levels. In group II, two patients had normal Oc levels and two had elevated Oc levels. In treated patients with good control of hyperthyroidism, all group II patients except one, had normal serum Oc levels and bone mineralization remain normal (n = 5) after 0.6 to 4.6 yrs of follow-up. In group I patients, although height velocity was normal, elevated (n = 4) or slightly elevated (n = 1) serum Oc levels and severe bone demineralization (n = 7 cases) persisted after 0.5 to 3 yrs of good control of the hyperthyroidism. Although the method used for measuring bone mineralization is potentially less precise than bone densitometry and not all the patients had serum osteocalcin measurements at the same time of the illness, our results emphasize that skeletal demineralization may be particularly marked in young children with Grave's disease and should be carefully evaluated.

Hypothalamopituitary deficiency and precocious puberty following hyperhydration in diabetic ketoacidosis.

We report on a 5-year-old child who survived an intracerebral crisis, following ketoacidosis-revealing diabetes (DKA), with visual impairment due to a vascular occipital lesion. Two and 4 months after the initial episode, a unique hypothalamopituitary disorder consisting in GH, ACTH, TSH deficiencies and central precocious puberty, was detected. Cranial magnetic resonance images showed no visible lesion in the hypothalamopituitary region. The most likely hypothesis is the ischemia of hypothalamopituitary and occipital regions following possible cerebral edema after hyperhydration. She survived with low visual acuteness and received a combined replacement therapy for the neuroendocrinological deficiencies. This case emphasizes that the rehydration at the initial period of DKA is critical, especially when risk factors for cerebral edema are present (young age, marked hyponatremia). The neuroendocrinological consequences of acute cerebral edema are rare, but physicians must be attentive in survivors of these accidents.