Management of an ABO-Incompatible Lung Transplant

A 24-year-old woman with cystic fibrosis underwent bilateral sequential lung transplantation and unintentionally received an ABO incompatible graft (blood type A(1) graft into a type O recipient). The recipient had a high titer of IgG anti-A antibody (256 by the indirect antiglobulin test). Emergency treatment included antibody removal by plasmapheresis and additional immunosuppression with mycophenolate, rabbit antithymocyte globulin and polyspecific intravenous immunoglobulin. Subsequently, immunoadsorption and the anti-CD20 antibody rituximab were used to remove anti-A antibody and inhibit its resynthesis. Early graft function was good; one episode of rejection at Day 46 responded promptly to treatment with methylprednisolone. Subsequently, graft function continued to improve and anti-A antibody titers remained low. No infectious or other complications were encountered. The treatment regimen that we adopted may prove useful in other cases of unplanned ABO-incompatible organ transplants. The successful outcome suggests that planned ABO-incompatible lung transplants may be possible.     

Can Vco2‐Based Estimates of Resting Energy Expenditure Replace the Need for Indirect Calorimetry in Critically Ill Children?

Background: Optimal energy provision, guided by measured resting energy expenditure (REE), is fundamental in the care of critically ill children. REE should be determined by indirect calorimetry (IC), which has limited availability. Recently, a novel equation was developed for estimating REE derived from carbon dioxide production (Vco ₂). The aim of this study was to validate the accuracy of this equation in a population of critically ill children following cardiopulmonary bypass (CPB). Methods: This is an ancillary study to a larger trial of children undergoing CPB. Respiratory mass spectrometry was used measure oxygen consumption (Vo ₂) and Vco ₂. REE was then calculated according to the established Weir equation (REE_W) and the modified, Vco ₂‐based equation (REE_CO2). The agreement between the 2 measurements was assessed using Bland‐Altman plots and mixed‐model regressions accounting for repeated measures. Results: Data from 104 patients, which included 575 paired measurements, were included. The agreement between REE_W and REE_CO2 was biased during the 72‐hour observation period post CPB, with a mean percentage error between measurements of 11% (±7%). The most important determinant of the bias with the Vco ₂‐based equation was the respiratory quotient (RQ). The percentage error between REE_W and REE_CO2 dropped to 4.4% (±2.4%) in those with an RQ between 0.8 and 1. The within‐subject variability for RQ in this cohort was wide (11%). Conclusions: IC remains the most accurate method to determine the REE of critically ill patients. Widespread availability of Vco ₂ data renders Vco ₂‐based approaches to measurement of REE attractive; however, further research is needed to ensure that REE is estimated accurately.     

Entecavir treatment of children 2–16 years of age with chronic hepatitis B infection

Background and study aimsChildhood acquired chronic hepatitis B is associated with a significant lifetime risk of developing cirrhosis or hepatocellular carcinoma. Our objective in this study was to report retrospectively the response to treatment with Entecavir in 8 children with chronic hepatitis B followed at the King Abdulaziz University Hospital, Jeddah, Saudi Arabia.Patients and methodsThis study is an observational hospital based chart review of children and adolescents with chronic hepatitis B treated with entecavir at the King Abdulaziz University Hospital, Jeddah, Saudi Arabia in the period between June 2007 and July 2011.ResultsHalf of the studied group was males, and the median age at the time of treatment was 4.8 years (range, 2.6–15). All subjects displayed infection with HBV genotype D and all were HBeAg positive. Half of the patients had been previously treated with lamivudine, while the remaining half was treatment naïve patients. The mean ALT ± SD was 84.9 ± 34.7 IU/L (range, 46–133) and the mean HBV DNA was 5.01 × 10⁸ ± 5.7 × 10⁸ IU/mL (range, 5.5 × 10⁷–1.3 × 10⁹). Patients were treated with a daily oral dose of 0.5 mg entecavir, and the mean duration of treatment was 23.8 ± 11.9 months, (range 14.9–44.7 months). HBV DNA suppression of more than 2 log₁₀ was achieved in all patients. HBV DNA was undetected in 37.5%, with ALT normalization in 87.5% and lastly HBeAg seroconversion and loss occurred in 37.5%. No adverse side effects were observed during the treatment with entecavir.ConclusionWe conclude from this limited data that 37.5% of children treated with entecavir achieved HBeAg loss and seroconversion with no side effects observed during treatment period, however long term safety and efficacy in children should be demonstrated through a multicenter study, enrolling large number of patients.     

Self-Reported Asthma in Chaldeans,Arabs, and African Americans: Factors Associated with Asthma

Although the prevalence of asthma is increasing worldwide, there are striking, and largely unexplained differences across various racial and ethnic groups. The current study looks at the prevalence of asthma and risk factors between Chaldeans, Arabs, and African Americans. We used Health Assessment Survey data representing 3,136 respondents. Prevalence across the three ethnic groups were compared using unadjusted and adjusted odds ratios, accounting for multiple risk factors. There were significant socio-demographic differences across all ethnic groups. Asthma prevalence was significantly lower in Arabs (9.4%) and Chaldeans (5.4%) than in Non-Middle Eastern Whites (14.4%). African American prevalence was 14.4%. The significantly lower prevalence of asthma among Chaldean and Arabs, as compared to African Americans, were not explained by traditional risk factors included in our models. We therefore, suggest that future studies should explore the possible role of ethnic-specific differences in gene × environmental interactions in the precipitation and/or exacerbation of asthma.     

Inverted Left Atrial Appendage Masquerading as a Cardiac Mass

An inverted left atrial appendage is a rare phenomenon post cardiac surgery. The lesion presents as an additional mass in the left atrium, which would trigger unnecessary concerns and frequently, a battery of tests. The lesion can be easily diagnosed using echocardiography. We report a case of inverted left atrial appendage in a patient post repair of common arterial trunk. Echocardiographic pictures and features which help to identify this lesion as well as to differentiate it from other possible left atrial mass are described. This article aimed to improve the awareness of sonographers toward this rare but possible post operative lesion.     

Plasma vascular endothelial growth factor in sleep apnea syndrome: effects of nasal continuous positive air pressure treatment

Sleep apnea syndrome is associated with recurrent episodic hypoxia during sleep, which has been implicated in the development of cardiovascular morbidity. Hypoxia is the major stimulus of vascular endothelial growth factor (VEGF), which is a potent angiogenic cytokine. In the present article we describe the results of three experiments in which plasma concentrations of VEGF were measured in patients with sleep apnea. In Experiment 1, apnea-hypopnea index was found to be a significant independent predictor of morning VEGF concentrations in 85 male subjects investigated in the sleep laboratory, of whom 47 had an apnea-hypopnea index greater than 20. In Experiment 2, VEGF concentrations measured hourly during the sleep period were found to be significantly higher in a group of five sleep apnea patients compared with six age-similar snorers and six normal young adults (129.1 +/- 43.4 versus 74.6 +/- 11.5 and 32.5 +/- 12.8 pg/ml, respectively [p < 0.007]). In Experiment 3, VEGF concentrations were compared in patients with sleep apnea before and 1 year after nasal continuous positive airway pressure treatment. A significant decrease in VEGF concentrations was found only in patients in whom nocturnal hypoxia improved after treatment (57.1 +/- 62.5 versus 39.6 +/- 46.9 pg/ml, p < 0.01). There was no comparable improvement in patients who did not accept treatment (53.9 +/- 23.6 versus 54.0 +/- 21.5 pg/ml, ns). These results raise the possibility that VEGF may contribute to the long-term adaptation of sleep apnea syndrome to recurrent nocturnal hypoxia.     

Peginterferon alfa-2b plus ribavirin for the treatment of chronic hepatitis C genotype 4

BACKGROUND: The hepatitis C virus (HCV) genotype is an important predictive parameter for the success of pegylated interferon plus ribavirin therapy. To date, most published therapeutic trials have enrolled patients infected mainly with HCV genotypes 1, 2, and 3. Data regarding the responsiveness of genotype 4, the predominant type of HCV in the Middle East, are very limited. OBJECTIVE: To assess the efficacy of peginterferon alfa-2b in combination with ribavirin for the treatment of chronic hepatitis caused by HCV genotype 4. METHODS: Sixty-six treatment-naive patients infected with HCV genotype 4 were enrolled in this open label, prospective study. Cohort characteristics included the following: 48 M/18 F, mean age 45 +/- 9 years, and mean weight 74 +/- 8 kg. All patients had raised alanine aminotransferase (ALT) and were compensated. The mean pretreatment HCV-RNA level was 4.2 x 10(6) copies/ml (8.4 x 10(5) iu/ml) and median was 2.15 x 10(6) copies/ml. Twenty patients (29%) exhibited cirrhosis or severe fibrosis on pretreatment liver biopsy specimens. Participants were to receive peginterferon alfa-2b, 1.5 mcg/kg/wk plus ribavirin 1,000-1,200 mg/day for 48 wk. Patients were followed up for 24 wk after completing therapy. End of treatment viral response and sustained viral response (SVR) were defined as the absence of HCV-RNA from serum (<100 copies/ml) at 48 wk of treatment and at the end of follow-up, respectively. Data were analyzed on an intention-to-treat basis. RESULTS: End of treatment and sustained virologic response were 77% and 68%, respectively. Among patients with pretreatment HCV-RNA > or =2 x 10(6) SVR was 55% compared with SVR of 86% among patients with HCV-RNA < 2 x 10(6) (p= 0.05). Patients with cirrhosis or severe fibrosis had significantly lower SVR rate compared to those with mild or no fibrosis (29 vs 84%; p < 0.0002). Three patients (4%) discontinued therapy because of severe flu-like symptoms. Four patients developed hypothyroidism. Dose reduction of ribavirin and peginterferon alfa-2b was necessary in 15% and 6% of the patients, respectively. CONCLUSION: Peginterferon alfa-2b in combination with ribavirin is effective in the treatment of HCV genotype 4. The treatment was well tolerated by most of the patients.