Effects of cyclooxygenases inhibitors on vasoactive prostanoids and thrombin generation at the site of microvascular injury in healthy men.

OBJECTIVE: Balance between vasoactive prostanoids that contribute to homeostasis of the circulatory system can be affected by cyclooxygenases inhibitors. Results of a recent large clinical trial show that myocardial infarction was more frequent among patients with rheumatoid arthritis treated with the selective cyclooxygenase-2 inhibitor rofecoxib compared with those treated with naproxen. Whether this difference was attributable to deleterious cardiovascular effects of rofecoxib or cardioprotective effects of naproxen has not been determined. We tested the hypothesis that naproxen, contrary to rofecoxib, exerts antithrombotic effects. METHODS AND RESULTS: Forty-five healthy men were randomized to receive a 7-day treatment with rofecoxib (50 mg/d), naproxen (1000 mg/d), aspirin (75 mg/d), or diclofenac (150 mg/d). Formation of thromboxane, prostacyclin, and thrombin in the bleeding-time blood at the site of standardized microvascular injury was assessed before and after treatment. Naproxen, like aspirin, caused significant reduction of both thromboxane and prostacyclin, whereas diclofenac depressed prostacyclin synthesis but had no effect on tromboxane formation. Naproxen and aspirin significantly suppressed thrombin generation. Diclofenac showed a similar tendency, which did not reach statistical significance. Rofecoxib had no effect on any variables measured. CONCLUSIONS: In healthy men, naproxen exerts an antithrombotic effect at least as potent as aspirin, whereas rofecoxib does not affect hemostatic balance.

Klüver Bucy syndrome, unusual consequence of excessively rapid correction of severe hyponatremia.

INTRODUCTION: Features of Klüver-Bucy syndrome (KBS) include hypersexuality, hyperorality, placidity, visual agnosia, amnesia, hypermetamorphosis, and emotional and nutritional behavior changes. It is a clinical presentation of bitemporal disorders with limbic system abnormalities. The most common cause of KBS is herpes encephalitis. CASE DESCRIPTION: An otherwise healthy 61-year-old woman presented with mental status changes (MMSE-0) after 6 days of severe vomiting. Extracellular dehydration, hyponatremia (107 mmol/L), low levels of natriuresis, and mild hypokalemia were noted. The initial computed tomography (CT) of the brain was normal. Over 36 hours of hospitalization in a district hospital she developed unusual neuropsychiatric disorders: hypersexuality, hyperorality, absence, visual agnosia, sensory aphasia, amnesia, and depression typical of KBS. She was then transferred to a neurology department. Clear improvement was visible 3 months later: MMSE-22, moderation of hypersexuality and hyperorality, partial correction of amnesia and aphasia, regression of visual agnosia. But the prosopagnosia (face blindness) persisted, and the patient remained unable to differentiate positive and negative facial expressions. DISCUSSION: Intracranial mass, epilepsy, neuromeningeal infection and head trauma were all ruled out. Antiepileptic and antiherpetic agents were tested without success. There was no evidence of adrenal insufficiency or inappropriate vasopressin secretion. Only severe vomiting, corrected by water intake, could explain the hyponatremia. The first MRI showed bitemporal edema; 3 months later it showed large bitemporal lesions, both internal and external, with atrophy of the hippocampus and limbic system. These MRI findings are characteristic of KBS. To our knowledge, this is the only the second case of KBS with bitemporal myelinolysis reported related to excessively rapid correction of hyponatremia (increase of 30 mmol/L over 36 h), which leads more usually to central pontine myelinolysis.