Review article: breath analysis in inflammatory bowel diseases

BACKGROUND

There is an urgent need for cheap, reproducible, easy to perform and specific biomarkers for diagnosis, differentiation and stratification of inflammatory bowel disease (IBD) patients. Technical advances allow for the determination of volatile organic compounds in the human breath to differentiate between health and disease.

AIM

Review and discuss medical literature on volatile organic compounds in exhaled human breath in GI disorders, focusing on diagnosis and differentiation of IBD.

METHODS

A systematic search in PubMed, Ovid Medline and Scopus was completed using appropriate keywords. In addition, a bibliography search of each article was performed.

RESULTS

Mean breath pentane, ethane, propane, 1-octene, 3-methylhexane, 1-decene and NO levels were elevated (P < 0.05 to P < 10(-7)) and mean breath 1-nonene, (E)-2-nonene, hydrogen sulphide and methane were decreased in IBD compared to healthy controls (P = 0.003 to P < 0.001). A combined panel of 3 volatile organic compounds (octene, (E)-2-nonene and decene) showed the best discrimination between paediatric IBD and controls (AUC 0.96). Breath condensate cytokines were higher in IBD compared to healthy individuals (P < 0.008). Breath pentane, ethane, propane, isoprene and NO levels correlated with disease activity in IBD patients. Breath condensate interleukin-1β showed an inverse relation with clinical disease activity.

CONCLUSIONS

Breath analysis in IBD is a promising approach that is not yet ready for routine clinical use, but data from other gastrointestinal diseases suggest the feasibility for use of this technology in clinical practice. Well-designed future trials, incorporating the latest breath detection techniques, need to determine the exact breath metabolome pattern linked to diagnosis and phenotype of IBD.

Liver Transplantation for Hepatitis B in Early Adulthood: Analysis of the United Network for Organ Sharing Database

BACKGROUND

Chronic hepatitis B virus (HBV) infection has a mild course in most children that may delay initiation of treatment even when indicated. Unfortunately, a small number of cases can progress rapidly to cirrhosis, which may require liver transplantation (LT) in early adulthood. The aim of this study was to assess the characteristics of HBV-positive young adults who received LT and to evaluate post-transplant outcomes including patient and graft survival and differences between pre- and post-implementation of Model for End-stage Liver Disease (MELD) prioritization.

METHODS

The United Network for Organ Sharing (UNOS) database review was conducted from 1987 to 2012, and a retrospective analysis was performed on all young adult patients (ages 18-35 years) who underwent LT in the United States with a primary diagnosis of HBV or were seropositive for HBV surface antigen at time of LT. Kaplan-Meier analysis was used to assess patient and graft survival in the pre-MELD and post-MELD eras. Factors associated with survival were identified through the use of Cox regression analysis.

RESULTS

A total of 522 HBV-infected subjects were included. Average age at time of transplant was 28.4 ± 5.2 years; 60.9% were male, 48.6% were white, the mean body mass index was 25 ± 5.5 kg/m², diabetes was present in 3.9%, hepatocellular carcinoma (HCC) was present in 4.4%, and 10.4% were on dialysis prior to LT. Median follow-up after first LT was 48.2 months [12.5, 109]. During this time, 174 (33.3%) patients died with a mean age at the time of death of 31.6 ± 7.8 years, including 144 of 522 (28%) after the first LT, 26 of 74 (35%) after the second LT, and 4 of 12 (33%) after the third LT. The most common cause of death was graft failure (27.6%), followed by infection (16.6%). Overall, only 58% of patients were alive with their first LT at last follow-up. Kaplan-Meier analysis revealed worse patient and graft survival after re-transplantation in comparison to initial LT. Three hundred thirty subjects were transplanted in the pre-MELD era and 192 were transplanted in post-MELD era. Obesity, HCC, shorter ventilation use, shorter cold ischemia time, and non-white donor race were significantly more common in the post-MELD era (all with P < .05). Importantly, 5-year patient and graft survival rates were higher in the post-MELD era compared with the pre-MELD era.

CONCLUSIONS

LT in young adults for HBV has poor outcomes and can be associated with premature death. These findings should prompt more aggressive evaluation and treatment for HBV in young patients. Superior outcomes in the post-MELD era compared with the pre-MELD era may be attributed to pre-transplant factors, improved surgical technique, and better treatment options for HBV infection.

Treatment of Recurrent Hepatitis C Genotype-4 Post-Liver Transplantation with Sofosbuvir plus Simeprevir

Hepatitis C virus (HCV) infection remains a leading indication for orthotopic liver transplantation (OLT) worldwide. Recurrence of HCV following OLT is universal. There is scarcity of data on the post-OLT treatment of HCV genotype-4-the predominant genotype in North Africa and the Middle East. Herein, we present three patients who have experienced HCV genotype-4 recurrence post-OLT. All three patients were interferon-naive and were treated with simeprivir (SIM) and sofosbuvir (SOF) combination therapy for 12-24 weeks. The data from this case series show that SIM+SOF are well-tolerated and effective for achieving viral clearance in HCV genotype-4 post-OLT patients. Given the limited nature of a case series, further research must be pursued regarding post-OLT HCV genotype-4 responses to direct-acting anti-viral therapy.

Sofosbuvir and Simeprevir for the Treatment of Recurrent Hepatitis C with Fibrosing Cholestatic Hepatitis after Liver Transplantation

Fibrosing cholestatic hepatitis (FCH) is an aggressive form of hepatitis C virus (HCV) recurrence after orthotopic liver transplantation (OLT), which frequently results in graft failure and death. Treatment of FCH remains challenging, and the optimal antiviral therapy is yet to be determined. Between November 2013 and early 2015, 62 patients with HCV cirrhosis underwent OLT at our transplant center, of whom, 5 patients developed recurrence HCV in the form of severe FCH and were treated with sofosbuvir and simeprevir (SOF-SMV) for 24 weeks. All patients achieved significant improvement of HCV viral load and had undetectable viral PCR at 6-8 week of treatment. The HCV RNA remained undetectable throughout treatment course. The first two patients achieved SVR at week 12 after completion of the treatment. There were significant histologic and biomarkers improvements after initiation of the treatment. One patient developed refractory pruritus and acute pancreatitis. The second, fourth and fifth patients had very benign treatment courses with no side effects recorded. The third patient was starting the treatment with multiple comorbid conditions. His course was complicated with hepatic artery thrombosis, and later developed sepsis and renal failure. Therefore, it seems that the combination of SOF-SMV is an efficacious oral regimen in OLT recipient with recurrent hepatitis C and FCH. However, safety profile needs to be carefully evaluated.