The Natural History of Scoliosis in Females With Rett Syndrome.

STUDY DESIGN: Population-based longitudinal observational study. OBJECTIVE: To describe the prevalence of scoliosis in Rett syndrome, structural characteristics and progression, taking into account the influences of age, genotype, and ambulatory status. SUMMARY OF BACKGROUND DATA: Scoliosis is the most common orthopedic comorbidity in Rett syndrome yet very little is known about its natural history and influencing factors such as age, genotype, and ambulatory status. METHODS: The infrastructure of the Australian Rett Syndrome Database was used to identify all cases with confirmed Rett syndrome in Australia and collect data on genotype and walking status. We identified radiological records and described the Cobb angle of each curve. Time to event analysis was used to estimate the median age of onset of scoliosis and the log-rank test to compare by mutation type. Latent class group analysis was used to identify groups for the trajectory of walking status over time and a multilevel linear model used to assess trajectories of scoliosis development by mutation type and walking status. We used a logistic regression model to estimate the probability of developing a scoliosis with a Cobb angle >60° at 16 years in relation to Cobb angle and walking status at 10 years of age. RESULTS: The median age of scoliosis onset was 11 years with earliest onset in those with a p.Arg255 mutation or large deletion. Scoliosis was progressive for all mutation types except for those with the p.Arg306Cys mutation. Scoliosis progression was reduced when there was capacity to walk independently or with assistance. Cobb angle and walking ability at age 10 can be reliably used to identify those who will develop a very severe scoliosis by age 16. CONCLUSION: These data on prognosis of scoliosis inform clinical decision making about the likelihood of progression to very severe scoliosis and the need for surgical management. LEVEL OF EVIDENCE: 4.

Continuous versus intermittent infusion of furosemide in acute decompensated heart failure.

BACKGROUND: Despite advances in the treatment of chronic ambulatory heart failure, hospitalization rates for acute decompensated heart failure (ADHF) remain high. Although loop diuretics are used in nearly all patients with ADHF to relieve congestive symptoms, optimal dosing strategies remain poorly defined. METHODS AND RESULTS: This was a prospective, randomized, parallel-group study comparing the effectiveness of continuous intravenous (cIV) with intermittent intravenous (iIV) infusion of furosemide in 56 patients with ADHF. The dose and duration of furosemide as well as concomitant medications to treat ADHF were determined by physician preference. The primary end point of the study was net urine output (nUOP)/24 hours. Safety measures including electrolyte loss and hemodynamic instability were also assessed. Twenty-six patients received cIV and 30 patients received iIV dosing. The mean nUOP/24 hours was 2098+/-1132 mL in patients receiving cIV versus 1575+/-1100 mL in the iIV group (P=.086). The cIV group had significantly greater total urine output (tUOP) with 3726+/-1121 mL/24 hours versus 2955+/-1267 mL/24 hours in the iIV group (P=.019) and tUOP/mg furosemide with 38.0+/-31.0 mL/mg versus 22.2+/-12.5 mL/mg (P=.021). Mean weight loss was not significantly different between the groups. The cIV group experienced a shorter length of hospital stay (6.9+/-3.7 versus 10.9+/-8.3 days, P=.006). There were no differences in safety measures between the groups. CONCLUSIONS: The cIV of furosemide was well tolerated and significantly more effective than iIV for tUOP. In addition, continuous infusion appears to provide more efficient diuresis.

Effects of concomitant amiodarone and haloperidol on Q-Tc interval prolongation.

PURPOSE: The effects of concomitant amiodarone and haloperidol on Q-Tc interval prolongation were studied. METHODS: All adult patients admitted to a 618-bed tertiary referral teaching hospital between January 1, 2005, and December 31, 2006, who received amiodarone and haloperidol concomitantly were included in this retrospective descriptive analysis. Data collected to assess patients' risk of developing Q-T interval prolongation included age, sex, past medical history, and number of days of concomitant exposure. Data relevant for the assessment of cardiac effects were collected for the time period between 24 hours before and after the administration of haloperidol and included laboratory test values, use of other Q-T interval-prolonging drugs, heart rate, Q-Tc intervals, and clinical documentation of arrhythmia. To determine change in the Q-Tc interval, Q-T and R-R values were recorded using cardiac rhythm strips or electrocardiogram. Nurses' and physicians' records were reviewed to determine if an arrhythmia occurred. Descriptive statistics were used to analyze baseline patient information and Q-Tc interval data. RESULTS: A total of 49 patients met inclusion criteria, yielding 381 distinct amiodarone-haloperidol exposures. During 138 (36.2%) of 381 haloperidol-amiodarone exposures, patients received at least one additional Q-T interval-prolonging drug. When amiodarone-haloperidol exposures were grouped by the number of concomitant Q-T prolonging drugs, no apparent association was detected between longer Q-Tc intervals and an increased number of concomitant Q-T interval-prolonging drugs. CONCLUSION: A small, potentially significant Q-Tc interval prolongation, but not ventricular arrhythmia, was observed in adult patients who received a concomitant administration of amiodarone and haloperidol at a tertiary referral teaching hospital.