Population pharmacokinetics of amikacin in critically ill patients.

The pharmacokinetic parameters of amikacin were determined in a population of 20 adults and 36 pediatric patients admitted into an intensive care unit. Amikacin was administered by repeated intravenous infusion over 0.5 h (600 to 1,350 mg for adults; 70 to 1,500 mg for children). The number of administrations ranged from 2 to 17, and the number of samples collected from each patient ranged from 2 to 70. The population enrolled in the study had large variabilities in age (0.5 to 85 years), weight (6 to 95 kg), height (72 to 187 cm), creatinine clearance rate (18 to 110 ml/min), blood urea nitrogen concentration (1.5 to 15 mmol/liter), and total protein concentration (30 to 91 g/liter). The mean population parameters and their interindividual variabilities were obtained for an initial group of 44 patients (16 adults and 28 children). A two-compartment model was fitted to the population data by using the computer program P-PHARM. Model selection was guided by evaluation of the minimum objective function and the weighted residuals. The population analysis has been performed with the complete set of the collected data, including the individual serum amikacin concentration together with the individual estimate of the creatinine clearance values. The potential sources of variability in the population parameters were investigated by using patients' age, height, weight, creatinine clearance, blood urea nitrogen concentration, and total protein concentration as covariables. A test group of 12 additional patients (4 adults and 8 children) was used to evaluate the predictive performances of the population parameters. The individual pharmacokinetic parameters were computed by a Bayesian fitting procedure. From the resulting individualized values of the parameters, the concentrations of amikacin in the serum of the patients were calculated. To evaluate the performance of the Bayesian estimation, the experimental concentrations were compared with the predicted ones. The Bayesian approached developed in the study accurately predicts amikacin concentrations in serum and allows for the estimation of amikacin pharmacokinetics parameters, minimizing the risk of bias in the prediction. This was demonstrated in patients with both stable and unstable renal functions.

[A rare complication of multiple exostoses: hemothorax]. / Une complication rare de la maladie exostosante: l'hémothorax.

BACKGROUND: Hemothorax is a rare complication of hereditary multiple exostosis. CASE REPORT: A 12 year-old boy suffered from abrupt thoracic pain, firstly attributed to pleural effusion. He had hereditary multiple exostosis known since the age of 9 years. The patients was given anti-inflammatory drugs and erythromycin but the pleural effusion became more abundant 6 days later requiring thoracentesis which showed hemothorax. All bacteriological and cytologic investigations were negative. X rays, ultra-sonography and CT scan showed several costal exostoses developing into the thoracic cavity. The hemothorax disappeared within 12 days and the patient was well 4 months later, without pleural sequelae. CONCLUSIONS: Hemothorax may be due to internal costal exostosis. It may be cured with thoracentesis; more aggressive therapy should be performed in exceptional cases with severe and/or recurrent bleeding.

[Epstein-Barr virus infection and syndrome of inappropriate macrophage activation]. / Infection à virus Epstein-Barr et syndrome d'activation macrophagique inappropriée.

An 11-year-old girl presented with a typical serologically proven infectious mononucleosis with persistent fever, jaundice and hepatosplenomegaly in spite of steroid therapy. Laboratory tests showed pancytopenia, fibrinopenia and hypertriglyceridemia. The liver biopsy revealed an infiltration with hyperbasophilic cells. One month later, a slight improvement was noted and fever disappeared after 4 days on acyclovir therapy. The authors recall the spectrum of the macrophagic activation syndrome.

[Desmopressin and water intoxication. Apropos of a case treated for enuresis]. / Desmopressine et intoxication par l'eau. A propos d'un cas traité pour énurésie.

A 4-year-old boy was treated with oxybutinine and desmopressine because of bladder instability associated with secondary enuresis. He was admitted with obnubilation, vomiting and experienced two seizure episodes concomitantly with hyponatremia and hypoosmolality. The child healed promptly under water restriction and intravenous administration of sodium chloride. This case report suggests that desmopressine may be responsible for severe side-effects. This drug should not be widely used and its indications should be restricted to patients with proven antidiuretic hormone secretion abnormalities.

[Pyloric stenosis with rare etiology]. / Sténose pylorique d'étiologie rare.

The authors report on a 30 month-old boy who experienced pyloric stenosis related to an hamartoma. This case shows the difficulties in such a clinical and histological diagnosis.

[Duodenopancreatic contusions. Diagnostic difficulties in children]. / Contusions duodéno-pancréatiques. Difficultés diagnostiques chez l'enfant.

The authors describe a case of duodenopancreatic injury in a 6-year-old girl, with the clinical presentation of appendicitis. The findings point to the importance of a precise anamnesis, as in its mild form the traumatism is often poorly recognized, and may be incorrectly diagnosed. It is therefore recommended that a thorough clinical examination be carried out, with abdominal ultrasonography, X-ray barium and tomodensitometry if necessary. Frequently, as is the case with other abdominal, injuries, surgery may be avoided if the patient's condition is carefully followed.

[Torsion of the ovary in children: value of echography and difficulties of anatomical interpretation]. / Torsion de l'ovaire chez l'enfant: intérêt de l'échographie et difficultés d'interprétation anatomique.

Two cases with the clinical presentation of peritonitis and a 9 year-old girl with ovarian torsion are reported: a 2 year-old girl with paroxistic abdominal pain and occlusive syndrome. Ultrasonography was of main interest in that situation. The necrotized ovary was extracted at intervention in both cases; histological data did not allow to distinguish the torsion on an hemangiomatous ovary from the torsion of an healthy ovary, which represents an exceptional feature.

[Spinal intradural arachnoid cyst]. / Kyste arachnoïdien intra-dural rachidien.

The authors report the case of a 13 year-old boy who presented after minor cranial trauma with severe gastrointestinal symptoms (acute hemorrhage) followed by neurologic signs evoking a spinal compression. Gastro-intestinal hemorrhage was related to a duodenal lesion induced by acetylsalicylic acid. Neurologic symptoms were related to an intra dural cervical arachnoid cyst. After surgical resection of this congenital malformation outcome was favorable.