Inherited DNA amplification of the proximal 15q region: cytogenetic and molecular studies

In a 15 year old girl, referred for growth retardation, conventional cytogenetic analysis detected an abnormal 15q+ chromosome with extra material in the proximal region, inherited from her father and grandfather. Using various molecular cytogenetic techniques, including comparative genomic hybridisation, we showed that the extra chromatin resulted from in situ amplification of DNA sequences located between the loci D15Z1 and D15S18. On the basis of the clinical features of our patient and the late replication of the large amplified region, we searched for functional modifications in the adjacent Prader-Willi syndrome region.

Utilization of neural network in the elaboration of an evaluation scale for pain in cerebral palsy

An interesting aspect of neural networks is shown in the elaboration of an evaluation scale for pain in cerebral palsy with severe mental retardation. Because of the diversity of cases, the number of items had to be limited in the final step of statistical validation. Classical analysis on prior data did not allow to decide whether the variability in results is more likely due to the type of disability (i.e., the possibility of pain expression) than to the actual presence of pain. A neural network was used to find implicit relations between the data, with the advantage of having total control on the variables' status by applying variations in the network architecture. This allowed for the rapid identification more significant item combinations as a function of degree of relationship to pain in cerebral palsy.

How well are endoscopes cleaned and disinfected between patients?

A questionnaire was sent to 276 hospitals throughout Australia to obtain details on the methods that are used in these institutions for the cleaning and disinfection of endoscopes. A broad range of hospitals was surveyed and 145 responses were received. Endoscopies were performed in 123 of the responding hospitals. Only 45% (55/123) of these hospitals both cleaned and disinfected their endoscopes satisfactorily. Generally, such hospitals were larger (300-600 beds) than were those which did not do so (100-300 beds) and also they were busier as more endoscopies were performed on a weekly basis (30.2 endoscopies compared with 19.3 endoscopies, respectively). Frequently (38% [47/123] of hospitals), the endoscopes were not disinfected between patients, or were disinfected for an insufficient time or were disinfected with an agent that did not have both antiviral and antibacterial activity. In a substantial proportion (40% [49/123]) of hospitals, endoscopes and their accessories appeared to be cleaned inadequately between patients. We conclude that in the majority of hospitals where endoscopies are performed that responded to our survey, there was considerable room for improvement in the cleaning and disinfection of endoscopes.

Streptococcus faecalis arthritis

Septic arthritis due to Streptococcus faecalis is rare. We describe a case in which synovial biopsy was required for diagnosis and a new longterm antibiotic combination using ciprofloxacin and amoxicillin was successful in treating the infection. Comparison is made with previous reported cases and the usual poor outcome in this condition.

Sepsis associated with central vein catheters in critically ill patients

In 440 critically ill patients, the association between different central vein catheter insertion sites, the duration of catheter insertion and catheter-associated sepsis was examined. Of 780 catheter tips studied, 19% were colonized by microorganisms. The incidence of colonization varied with the different insertion sites. The lowest percentage of colonized catheters occurred with catheters inserted via the subclavian vein (15%) and the highest, at the femoral vein insertion site (34%, p less than 0.01). The percentage of catheters colonized increased as the duration of insertion increased, at all insertion sites studied. Catheter colonization was closely related to the development of bacteraemia and was associated with approximately 10% of colonized catheters. Our results suggest that the subclavian site is associated with the lowest infective complication rate. To minimize catheter associated sepsis, catheters at all insertion sites should be used with parsimony and only kept in place for the minimum amount of time that their continuing use is necessary.

Localised form of spondylo-epiphyseal dysplasia congenita

We report an unusual case of spondylo-epiphyseal dysplasia congenita which affected only the hips and the thoraco-lumbar spine. The epiphysis of the long bones are normal apart from the hips. Our child has a bilateral epiphyseal dysplasia of both proximal femoral epiphysis discovered incidentally at 11 months and confirmed later on at 8 years, associated with abnormalities of the superior margin of the vertebral bodies from T11 to L2. Very few similar cases have been reported anteriorly.

Rapid diagnosis of intravascular catheter-related sepsis

The use of Gram-stained "impression smears" of the external surface of intravascular catheters for rapid detection of catheter-associated infection was studied. Gram's stain results of 322 catheters were correlated with clinical episodes of systemic sepsis and semiquantitative cultures of the catheters. Organisms were seen on Gram's stain of 82 catheters, 37 of which were positive on semiquantitative cultures (greater than or equal to 15 colonies per plate). Catheter-related bacteremia occurred on three occasions. All three catheters showed numerous organisms on Gram's stain, although one was negative on semiquantitative culture. All five catheters, in place during bacteremic episodes that were unrelated to catheter infection, were negative on Gram's stain. If the presence of any organisms on Gram's stain was taken as a positive test result, the sensitivity of Gram's stain in predicting the result of semiquantitative culture was 83%, the specificity was 81%, and the predictive value of a positive and negative culture was 44% and 96%, respectively. Slides took two to five minutes to examine microscopically. Gram-stained impression smears of intravenous catheters can be made by a simple, inexpensive, and rapid technique that is accurate in diagnosing catheter-related infection. However, in this study in which a relatively low prevalence of catheter-related bacteremia occurred, the positive predictive value of the Gram's stain result in the diagnosis of catheter-related bacteremia, in contrast to catheter colonization, was low. Only in a patient group with a high prevalence of catheter-related bacteremia would the test be likely to have a high positive predictive value. Thus, selectivity should be exercised in the application of this method.

Comparative haemodynamic effects of intravenous flecainide in patients with and without heart failure and with and without beta-blocker therapy

The haemodynamic effects of flecainide were compared in three different subsets of patients with documented coronary disease. Ten patients (A) had no heart failure, 5 patients were on beta blockers (B) and 5 patients had overt heart failure (C). Flecainide was associated with negative inotropic effects that were relatively more pronounced in patients with left ventricular dysfunction: pulmonary wedge pressure increased by 27% in A, by 31% in B and by 42% in C; left ventricular stroke volume and stroke work decreased respectively by 10 and 12% in A, 21 and 19% in B, 26 and 28% in C. Ejection fraction decreased by 9% in A, 13% in B and 20% in C, in relation with an increase in end systolic volume (+9% in A, +10% in B and +5% in C). Absolute changes, however, were not significantly different from one group to another except for the increase of systemic vascular resistance which was more pronounced in C as compared with the other groups. The myocardial depression was also confirmed by the fall in dP/dt that was maximal at the end of injection; dP/dt remained depressed 15 min later despite some improvement. Flecainide thus exerts negative inotropic effects that are maximal at the end of infusion and may be of importance in patients with established left ventricular dysfunction.

Prevention by acebutolol of rhythm disorders following coronary bypass surgery

Seventy-one patients submitted routinely to coronary artery bypass surgery were randomized into 2 groups. Group A (32 patients) received 24 hr after initiation of surgery an intravenous perfusion of 100 mg of acebutolol given over 24 hr (22 cases) or 600 mg administered orally (10 cases). On subsequent days, they received 1200 mg of acebutolol/day orally. Group B (39 patients) was used as control. The groups were comparable in terms of age, sex, severity of coronary disease, preoperative therapy, duration of extracorporeal circulation, aortic clamping time, and immediate postoperative haemodynamic findings. No patient received digitalis. During hospital stay (10 days), 1 group A patient (3%) and 13 group B patients (33%; P less than 0.001) developed a sustained episode of atrial arrhythmia (fibrillation, flutter or atrial ectopic tachycardia). The majority of these rhythm disorders developed between days 2 and 4. On Holter monitoring on days 7-10, malignant ventricular extrasystoles (grades IV and V of Lown's classification) were more frequent in group B (65.2%) than in group A (19.3%; P less than 0.001). Haemodynamic measurements taken at rest performed in 27 patients on days 7-10 (16 patients of group A; 11 of group B). No difference was observed between the two groups. Acebutolol is a safe and efficacious drug for the prevention of arrhythmias following coronary surgery.

Haemodynamic effects of class I antiarrhythmic agents

In order to choose the most appropriate antiarrhythmic agent, the basic haemodynamic characteristics of class I antiarrhythmic agents must be known. Class Ia agents, quinidine and procainamide, have minor haemodynamic effects, while disopyramide causes serious left ventricular depression. Class Ib drugs are exceptionally well tolerated, and class Ic agents have the potential for adverse haemodynamic effects in patients with left ventricular dysfunction. In this article, haemodynamic effects of class I antiarrhythmic agents are described, with particular emphasis on their clinical implications.

Hemodynamic effects of intravenous diltiazem with impaired left ventricular function

The acute hemodynamic effects of intravenous diltiazem were studied in 8 patients with coronary artery disease, left ventricular (LV) failure (New York Heart Association functional class III), a rest ejection fraction (EF) less than 40% or a cardiac index less than 2.4 liters/min/m2. Hemodynamic measurements and LV angiograms were performed at rest before and after the administration of diltiazem, 0.5 mg/kg, administered at a speed of 5 mg/min. Diltiazem treatment induced a decrease in heart rate from 68 +/- 12 to 55 +/- 9 beats/min (p less than 0.001). Mean aortic pressure decreased from 94 +/- 14 to 81 +/- 15 mmHg (p less than 0.05). Thus, the pressure-rate product significantly decreased under the influence of the drug, from 8,791 +/- 2,465 to 6,342 +/- 1,808 beats mm Hg/min, (p less than 0.001). Diltiazem induced no significant change of LV end-diastolic pressure, pulmonary wedge pressure, cardiac index and LV stroke work index. Systemic vascular resistance decreased (p less than 0.01), whereas pulmonary vascular resistance showed no change. End-systolic volume diminished (p less than 0.02), which accounts for the increase of stroke volume and ejection fraction (p less than 0.001). Disorders of regional contractility were not aggravated by diltiazem, and even improved in individual cases. Thus, intravenous diltiazem may be used safely in patients with heart failure. However, in view of the marked bradycardic effects seen in some cases, heart rate should be carefully monitored.

Haemodynamic effects of intravenous diltiazem at rest and exercise in patients with coronary artery disease

The acute effects of intravenous diltiazem on exercise performance were studied in 10 patients with coronary artery disease. Haemodynamic measurements were made at rest and during exercise before and after 0.5 mg kg-1 of diltiazem. Diltiazem prolonged the duration of exercise (+2.85 min, P less than 0.001) and delayed the onset of ischaemic ST depression or angina in all patients. The highest tolerated heart rate and pressure rate product were increased in all but one patient after diltiazem. At rest diltiazem decreased mean arterial pressure (-10.8%, P less than 0.005), systemic vascular resistance (SVR) (-11.8%, P less than 0.05) and left ventricular stroke work index (SWI) (-14.1%, P less than 0.005). During exercise under diltiazem therapy, at the level achieved before the drug, the pulmonary capillary wedge pressure (-30%, P less than 0.005) and the SVR (-13.6%, P less than 0.02) were lowered, the SWI (+13%, P less than 0.01) was increased; at the end of exercise only the SVR (-14%, P less than 0.05) was reduced. Two patients experienced angina on lying down and one had orthostatic hypotension after exercise with diltiazem. This study indicates that intravenous diltiazem is a potentially useful agent for the treatment of angina by reducing myocardial oxygen demand at rest and by improving left ventricular performances on exercise.

Hemodynamic effects of a new antiarrhythmic agent, flecainide (R-818), in coronary heart disease

The hemodynamic effects of flecainide acetate, a new class I antiarrhythmic agent, were studied in 10 patients with coronary heart disease. The drug was injected intravenously at a dose of 2 mg/kg over 30 minutes. The mean drug plasma level achieved was 394 ng/ml (range 329 to 470). The heart rate did not change, but a significant increase (p less than 0.001) in P-R (+17%), QRS (+15%), and Q-T (+7%) duration occurred after drug administration. Negative inotropic effects also were observed and consisted of an increase (p less than 0.01) in pulmonary wedge pressure (+27%) and a decrease (p less than 0.01) in stroke index (-10%), left ventricular stroke work index (-12%), and left ventricular ejection rate (-11%). No significant change in mean aortic pressure or systemic and pulmonary vascular resistance occurred. Left ventriculography performed after drug infusion revealed a significant increase (p less than 0.01) in systolic volume (+9%) and a decrease in ejection fraction (-9%) and mean velocity of circumferential fiber shortening (Vcf) (-13%). A progressive and significant decrease of dP/dt was observed during drug infusion, but 15 minutes after the injection, dP/dt had returned to near basal values. Thus, flecainide acetate has slight, but significant negative inotropic effects, particularly conspicuous during drug infusion. The drug should be administered with caution in patients with poorly compensated heart.

Right ventricular myocardial infarction diagnosed by 99 m technetium pyrophosphate scintigraphy: clinical course and follow-up

Out of 178 consecutive patients with acute inferior wall myocardial infarction submitted to technetium-99 m pyrophosphate scintigraphy, 49 (27.5%) were found to have concomitant right ventricular infarction. Gated blood pool scans showed right ventricular abnormalities in 21 out of 26 patients who were submitted to this investigation (right ventricular asynergy: 16 cases; right ventricular dilatation: eight cases; decreased right ventricular ejection fraction: 16 cases). Complications were common in the acute stage. Shock was noted in 19 cases (eight related to bradycardia, three related to relative hypovolaemia and eight instances of true cardiogenic shock). Atrial fibrillation (seven patients), ventricular fibrillation (eight patients) and severe atrioventricular conduction disorders (13 patients) were also frequent. In spite of this, the in-hospital mortality was low: three deaths occurred (6.1%), one from heart failure, two others from posterior septal rupture. All patients were followed up for one year or more. Six additional deaths were noted (three from left cardiac failure, two from recurrent anterior wall infarction and one from massive pulmonary embolism). Clinical assessment, haemodynamic measurements and gated blood pool scans showed significant improvement of right ventricular function with return to normal in those cases with small right ventricular infarcts as judged from technetium-99 m pyrophosphate scintigraphy. In spite of the complications seen in the initial period, patients with a right ventricular infarction have a good overall prognosis and the long-term outcome, primarily determined by the left-sided lesions, is often favourable.