The impact of chronic hepatitis B viral infection on gastrointestinal motility

Current Status and Prospects of Spontaneous Peritonitis in Patients with Cirrhosis

Spontaneous bacterial peritonitis (SBP) is a common cirrhotic ascites complication which exacerbates the patient's condition. SBP is caused by gram-negative bacilli and, to a lesser extent, gram-positive cocci. Hospital-acquired infections show higher levels of drug-resistant bacteria. Geographical location influences pathogenic bacteria distribution; therefore, different hospitals in the same country record different bacteria strains. Intestinal changes and a weak immune system in patients with liver cirrhosis lead to bacterial translocation thus causing SBP. Early diagnosis and timely treatment are important in SBP management. When the treatment effect is not effective, other rare pathogens should be explored.

Small Intestinal Bacterial Overgrowth in Patients With Cirrhosis

Small intestinal bacterial overgrowth (SIBO) is defined by increased density and/or abnormal composition of microbiota in the small bowel. SIBO is often encountered in patients with cirrhosis as a result of impaired intestinal motility and delayed transit time, both of which are exacerbated by more severe liver disease. Additional risk factors for SIBO commonly encountered in cirrhotic patients include coexisting diabetes, autonomic neuropathy, and/or alcoholic use. Diagnosis of SIBO is performed by breath testing or jejunal aspiration, the gold standard. In cirrhotic patients, the presence of SIBO can lead to profound clinical consequences. Increased intestinal permeability in these patients predisposes to bacterial translocation into the systemic circulation. As a result, SIBO is implicated as a significant risk factor in the pathogenesis of both spontaneous bacterial peritonitis and hepatic encephalopathy in cirrhotics. Antibiotics, especially rifaximin, are the best studied and most effective treatment options for SIBO. However, prokinetics, probiotics, nonselective beta-blockers, and treatment of underlying liver-related pathophysiology with transjugular intrahepatic portosystemic shunt placement or liver transplantation are also being investigated. This review will discuss the risk factors, diagnosis, manifestations in cirrhosis, and treatment options of SIBO.

Gastrointestinal Motility Disorders and Their Clinical Implications in Cirrhosis

Gastrointestinal motility is impaired in a substantial proportion of patients with cirrhosis. Cirrhosis-related autonomic neuropathy, increased nitric oxide production, and gut hormonal changes have been implicated. Oesophageal dysmotility has been associated with increased frequency of abnormal gastro-oesophageal reflux. Impaired gastric emptying and accommodation may result in early satiety and may have an impact on the nutritional status of these patients. Small intestinal dysmotility might be implicated in small intestinal bacterial overgrowth and increased bacterial translocation. The latter has been implicated in the pathophysiology of hepatic encephalopathy and spontaneous bacterial peritonitis. Enhanced colonic motility is usually associated with the use of lactulose. Pharmacological interventions aiming to alter gastrointestinal motility in cirrhosis could potentially have a beneficial effect reducing the risk of hepatic decompensation and improving prognosis.

Overlapping self-expandable metallic stent for palliation of a long (>10 cm) malignant gastroduodenal obstruction

Background Self-expandable metallic stent (SEMS) placement is a well-established palliative treatment approach for malignant gastroduodenal obstruction. In patients with a long (>10 cm) stricture, multiple stents placed in an overlapping fashion are often required. Purpose To investigate the outcomes of overlapping SEMS placement for the palliative treatment of malignant gastroduodenal obstruction in patients with a long (>10 cm) stricture. Material and Methods The medical records of 40 patients who underwent fluoroscopic overlapping SEMS placement for malignant gastroduodenal obstruction due to a long (>10 cm) stricture were reviewed. Results The technical and clinical success rates were 100% and 65.0%, respectively. The mean length of the stricture was 17.0 ± 4.7 cm and the mean number of stents placed in each patient was 2.2 ± 0.5. Metastatic cancer (odds ratio [OR], 0.315; P = 0.018), Eastern Cooperative Oncology Group (ECOG) score ≥3 (OR, 0.018; P = 0.006), and carcinomatosis with ascites (OR, 0.025; P = 0.017) were independent predictors of poor clinical success. The rates of minor and major complications were 27.5% and 2.5%, respectively. The median stent patency and survival were 33 days (interquartile range [IQR], 19-60 days) and 35 days (IQR, 19-73 days), respectively. An ECOG score ≥3 was an independent predictor of a poor survival outcome (hazard ratio, 4.681; P < 0.001). Conclusion Overlapping SEMS placement may be safe and effective for the palliative treatment of malignant gastroduodenal obstruction in patients with a long (>10 cm) stricture.

Changes of Intestinal Functions in Liver Cirrhosis

Background

Understanding of the gut-liver axis is important for the up-to-date management of liver cirrhosis, and changes of intestinal functions form the core of this interesting research field.

Summary

Most investigators noted small intestinal dysmotility in their patients with liver cirrhosis. Marked changes in the contraction pattern were observed in early manometric studies. The orocecal transit time, particularly small intestinal transit, has generally been reported to be prolonged, which has been demonstrated in multiple investigations to be related to the severity of the liver disease (e.g., Child-Pugh class), the presence of small intestinal bacterial overgrowth (SIBO) and hepatic encephalopathy (HE) as well as a history of spontaneous bacterial peritonitis. Bacteriologically proven SIBO in proximal jejunal aspiration has been reported to be present in up to 59% of cirrhotic patients and is associated with systemic endotoxemia. Clinical and experimental studies suggest that delayed small bowel transit in liver cirrhosis may lead to SIBO, which could contribute to the symptoms of abdominal pain and diarrhea. In addition to autonomic neuropathy, metabolic derangements and diabetic state, SIBO itself may delay intestinal transit in cirrhotic patients. Several studies, both from the West and the East, have shown that the gut microbiota is altered in cirrhotic patients and particularly those with HE. Further, a quantitative change in Bacteroides/Firmicutes ratio, with a prevalence of potentially pathogenic bacteria (e.g., Enterobacteriaceae) and reduction in specific commensals (e.g., Lachnospiraceae), has been described. Structural and functional changes in the intestinal mucosa that contribute to increases in intestinal permeability for bacteria and their products have been observed in patients with liver cirrhosis, which is considered as an important pathogenetic factor for several complications. The mechanism of intestinal barrier dysfunction in cirrhosis is multifactorial, including alcohol, portal hypertension (vascular congestion and dysregulation), endotoxemia, SIBO, local inflammation and, most likely, immunological factors and medications.

Key Messages

This review summarizes major achievements regarding intestinal dysfunction in cirrhosis for future gastroenterology research. The question of whether this intestinal barrier dysfunction is accompanied and/or at least partly caused by structural and functional changes in the epithelial tight junction proteins is as yet unsolved. Development of new strategies to modulate gut-liver interaction is urgently needed.

Changes of Intestinal Functions in Liver Cirrhosis

BACKGROUND

Understanding of the gut-liver axis is important for the up-to-date management of liver cirrhosis, and changes of intestinal functions form the core of this interesting research field.

SUMMARY

Most investigators noted small intestinal dysmotility in their patients with liver cirrhosis. Marked changes in the contraction pattern were observed in early manometric studies. The orocecal transit time, particularly small intestinal transit, has generally been reported to be prolonged, which has been demonstrated in multiple investigations to be related to the severity of the liver disease (e.g., Child-Pugh class), the presence of small intestinal bacterial overgrowth (SIBO) and hepatic encephalopathy (HE) as well as a history of spontaneous bacterial peritonitis. Bacteriologically proven SIBO in proximal jejunal aspiration has been reported to be present in up to 59% of cirrhotic patients and is associated with systemic endotoxemia. Clinical and experimental studies suggest that delayed small bowel transit in liver cirrhosis may lead to SIBO, which could contribute to the symptoms of abdominal pain and diarrhea. In addition to autonomic neuropathy, metabolic derangements and diabetic state, SIBO itself may delay intestinal transit in cirrhotic patients. Several studies, both from the West and the East, have shown that the gut microbiota is altered in cirrhotic patients and particularly those with HE. Further, a quantitative change in Bacteroides/Firmicutes ratio, with a prevalence of potentially pathogenic bacteria (e.g., Enterobacteriaceae) and reduction in specific commensals (e.g., Lachnospiraceae), has been described. Structural and functional changes in the intestinal mucosa that contribute to increases in intestinal permeability for bacteria and their products have been observed in patients with liver cirrhosis, which is considered as an important pathogenetic factor for several complications. The mechanism of intestinal barrier dysfunction in cirrhosis is multifactorial, including alcohol, portal hypertension (vascular congestion and dysregulation), endotoxemia, SIBO, local inflammation and, most likely, immunological factors and medications.

KEY MESSAGES

This review summarizes major achievements regarding intestinal dysfunction in cirrhosis for future gastroenterology research. The question of whether this intestinal barrier dysfunction is accompanied and/or at least partly caused by structural and functional changes in the epithelial tight junction proteins is as yet unsolved. Development of new strategies to modulate gut-liver interaction is urgently needed.

Changes of Intestinal Functions in Liver Cirrhosis

Background

Understanding of the gut-liver axis is important for the up-to-date management of liver cirrhosis, and changes of intestinal functions form the core of this interesting research field.

Summary

Most investigators noted small intestinal dysmotility in their patients with liver cirrhosis. Marked changes in the contraction pattern were observed in early manometric studies. The orocecal transit time, particularly small intestinal transit, has generally been reported to be prolonged, which has been demonstrated in multiple investigations to be related to the severity of the liver disease (e.g., Child-Pugh class), the presence of small intestinal bacterial overgrowth (SIBO) and hepatic encephalopathy (HE) as well as a history of spontaneous bacterial peritonitis. Bacteriologically proven SIBO in proximal jejunal aspiration has been reported to be present in up to 59% of cirrhotic patients and is associated with systemic endotoxemia. Clinical and experimental studies suggest that delayed small bowel transit in liver cirrhosis may lead to SIBO, which could contribute to the symptoms of abdominal pain and diarrhea. In addition to autonomic neuropathy, metabolic derangements and diabetic state, SIBO itself may delay intestinal transit in cirrhotic patients. Several studies, both from the West and the East, have shown that the gut microbiota is altered in cirrhotic patients and particularly those with HE. Further, a quantitative change in Bacteroides/Firmicutes ratio, with a prevalence of potentially pathogenic bacteria (e.g., Enterobacteriaceae) and reduction in specific commensals (e.g., Lachnospiraceae), has been described. Structural and functional changes in the intestinal mucosa that contribute to increases in intestinal permeability for bacteria and their products have been observed in patients with liver cirrhosis, which is considered as an important pathogenetic factor for several complications. The mechanism of intestinal barrier dysfunction in cirrhosis is multifactorial, including alcohol, portal hypertension (vascular congestion and dysregulation), endotoxemia, SIBO, local inflammation and, most likely, immunological factors and medications.

Key Messages

This review summarizes major achievements regarding intestinal dysfunction in cirrhosis for future gastroenterology research. The question of whether this intestinal barrier dysfunction is accompanied and/or at least partly caused by structural and functional changes in the epithelial tight junction proteins is as yet unsolved. Development of new strategies to modulate gut-liver interaction is urgently needed.

Impact of carcinomatosis and ascites status on long-term outcomes of palliative treatment for patients with gastric outlet obstruction caused by unresectable gastric cancer: stent placement versus palliative gastrojejunostomy

BACKGROUND

Self-expandable metal stent (SEMS) placement and palliative gastrojejunostomy (GJJ) are palliative treatment options for malignant gastric outlet obstruction.

OBJECTIVE

To compare clinical outcomes of palliative treatments for gastric outlet obstruction caused by unresectable gastric cancer.

DESIGN

Retrospective study.

SETTING

University-affiliated tertiary-care hospital in the Republic of Korea.

PATIENTS

Two hundred fifty-six patients with gastric outlet obstruction caused by unresectable gastric cancer.

INTERVENTION

SEMS placement and palliative GJJ.

MAIN OUTCOME MEASUREMENTS

Patency duration and overall survival duration.

RESULTS

In total, 217 and 39 patients underwent SEMS placement and palliative GJJ, respectively, as an initial palliative treatment. Treatment modality affected reobstruction after clinical success (hazard ratio [HR] [95% confidence interval {CI}], 0.5 [0.3-0.8] of palliative GJJ). In addition, carcinomatosis with ascites was an independent associated factor of clinical success and reobstruction (HR [95% CI], 0.3 [0.1-0.7] and 1.4 [1.0-2.0], respectively). In a subgroup of patients with good performance who had neither carcinomatosis nor ascites, patency duration and overall survival duration did not differ between the 2 groups (P = .079 and P = .290, respectively). In patients with good performance who had carcinomatosis without ascites, patency duration was longer in the palliative GJJ group than in the SEMS placement group (P = .016). Overall survival, however, did not differ between the 2 groups (P = .062). In a subgroup of patients with good performance who had carcinomatosis with ascites, both patency duration and overall survival were longer in the palliative GJJ group than in the SEMS placement group (P = .007 and P = .012, respectively).

LIMITATIONS

Nonrandomized, retrospective study.

CONCLUSION

Long-term clinical outcomes of the palliative treatment modality for gastric outlet obstruction caused by unresectable gastric cancer were affected by carcinomatosis and ascites status.

Carcinomatosis matters: clinical outcomes and prognostic factors for clinical success of stent placement in malignant gastric outlet obstruction

BACKGROUND

Although carcinomatosis is not a contraindication to stenting in selected patients with malignant gastric outlet obstruction (GOO), associate factors for clinical success rate of self-expandable metallic stent (SEMS) placement in GOO patients with carcinomatosis have not been fully characterized.

METHODS

We analyzed a total 228 patients who were scheduled for SEMS placement for malignant GOO in tertiary-care academic medical center. All patients were treated with an uncovered or covered SEMS by using the over-the-wire placement procedure. We retrospectively evaluated clinical outcomes of SEMS placement.

RESULTS

Technical success was achieved in all patients. Patients were categorized into two groups according to the presence of carcinomatosis. Clinical success rates of patients without carcinomatosis group and with carcinomatosis group were 93.9 % (92 of 98) and 80.8 % (105 of 130), respectively (P = 0.004). In subgroup analysis of patients with carcinomatosis, the clinical success rate was lower in patients with ascites (64.8 %) than in those without ascites (92.1 %, P < 0.001). Multivariate logistic regression model revealed that carcinomatosis without ascites did not decrease clinical success rate compared with absence of carcinomatosis; meanwhile, carcinomatosis with ascites showed lower clinical success rates compared with absence of carcinomatosis (adjusted odds ratio 0.163, 95 % confidence interval 0.058-0.461). In addition, poor performance status [Eastern Cooperative Oncology Group (ECOG) status ≥ 3, adjusted odds ratio 0.178, 95 % confidence interval 0.078-0.409] was also an independent poor predictive factor for clinical success of SEMS placement.

CONCLUSIONS

In palliation for malignant GOO, the status of carcinomatosis with ascites and poor performance status (ECOG status ≥ 3) are significant predictive factors for poor clinical success of SEMS placement.

Increased oro-cecal transit time in grade I or II hepatic encephalopathy

The pathogenic mechanisms of hepatic encephalopathy remain to be elucidated. It has been suggested that a digestive motor disorder could promote the absorption of toxins produced within the lumen and thus enhance hepatic encephalopathy.

AIM

To evaluate oro-cecal transit time in cirrhotic patients with and without hepatic encephalopathy.

METHODS

Hospitalized patients with alcoholic cirrhosis without encephalopathy and with spontaneous grade I and II encephalopathy were included. Severity of hepatic encephalopathy was assessed clinically and the Child-Pugh score was used to describe cirrhosis severity. Nine healthy volunteers constituted a control group. Oro-cecal transit time was measured with the sulfasalazine test.

RESULTS

Twenty-eight patients (mean age 62.5 +/- 8.5 years) were included. Ten had hepatic encephalopathy of unknown cause and 18 were free of hepatic encephalopathy. Oro-cecal transit time was significantly longer in patients with hepatic encephalopathy (641 +/- 350 min) compared to patients without hepatic encephalopathy (298 +/- 96; P<0.05) and to controls (354 +/- 90; P<0.05). Oro-cecal transit time was comparable for each Child-Pugh score and was not different between the two grades of hepatic encephalopathy.

CONCLUSION

Oro-cecal transit time is longer in alcoholic cirrhosis patients with hepatic encephalopathy. This digestive motor disorder provides a partial explanation of hepatic encephalopathy of unknown etiology.

Delayed gastrointestinal transit in patients with hepatocellular carcinoma

BACKGROUND AND AIM

Disturbed gastrointestinal (GI) motility exists in cirrhotic patients; however, less is known about the character of GI transit in hepatocellular carcinoma (HCC) patients. It is interesting to study the GI transit in HCC patients and to explore the patient factors modulating GI transit.

METHODS

A non-invasive hydrogen breath test, which measured the orocecal transit time (OCTT), was used to study GI transit in 40 HCC patients, 20 cirrhotics and 40 age- and sex-matched healthy volunteers with normal bowel habits. Meanwhile, their clinical manifestations and various blood parameters, such as platelet count, prothrombin time, erythrocyte sedimentation rate etc. were collected. The plasma endothelin-1 and nitrate/nitrite levels were also measured.

RESULTS

The OCTT were delayed in HCC and cirrhotic patients compared with controls (116.3 +/- 7.8 and 104.5 +/- 10.6 vs 75.3 +/- 5.1 min, P < 0.05). Neither the severity of liver damage, presence of ascites, tumor size, portal hypertension, nor various blood parameters, such as nitrate/nitrite, endothelin-1, platelet count etc., had any influence on GI transit. Only serum alpha-fetoprotein levels exhibited a trend toward positive correlation with the OCTT (r = 0.271, P = 0.091).

CONCLUSIONS

Hepatocellular carcinoma patients have delayed GI transit. The confounding factor responsible for the disturbance of GI transit in HCC patients needs further exploration.

Effect of L-NAME on nitric oxide and gastrointestinal motility alterations in cirrhotic rats

AIM: To investigate the effect of L-NAME on nitric oxide and gastrointestinal motility alterations in cirrhotic rats.

METHODS: Rats with cirrhosis induced by carbon tetrachloride were randomly divided into two groups, one (n = 13) receiving

0.5 mg·kg^-1 per day of N G-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, for 10 d, whereas the other group (n = 13) and control (n = 10) rats were administrated the same volume of 9 g•L⁻¹ saline. Half gastric emptying time and 2 h residual rate were measured by SPECT, using ^99mTc-DTPA-labeled barium sulfate as test meal. Gastrointestinal transition time was recorded simultaneously. Serum concentration of nitric oxide (NO) was determined by the kinetic cadmium reduction and colorimetric methods. Immunohistochemical SABC method was used to observe the expression and distribution of three types of nitric oxide synthase (NOS) isoforms in the rat gastrointestinal tract. Western blot was used to detect expression of gastrointestinal NOS isoforms.

RESULTS: Half gastric emptying time and trans-gastrointestinal time were significantly prolonged (124.0 ± 26.4 min; 33.7 ± 8.9 min; 72.1 ± 15.3 min; P < 0.01), (12.4 ± 0.5 h; 9.5 ± 0.3 h; 8.2 ± 0.8 h; P < 0.01), 2 h residual rate was raised in cirrhotic rats than in controls and cirrhotic rats treated with L-NAME (54.9% ± 7.6%, 13.7% ± 3.2%, 34.9% ± 10.3%, P < 0.01). Serum concentration of NO was significantly increased in cirrhotic rats than in the other groups (8.20 ± 2.48) μmol•L⁻¹, (5.94 ± 1.07) μmol•L⁻¹, and control (5.66 ± 1.60) μmol•L⁻¹, P < 0.01. NOS staining intensities which were mainly located in the gastrointestinal tissues were markedly lower in cirrhotic rats than in the controls and cirrhotic rats after treated with L-NAME.

CONCLUSION: Gastrointestinal motility was remarkably inhibited in cirrhotic rats, which could be alleviated by L-NAME.Nitric oxide may play an important role in the inhibition of gastrointestinal motility in cirrhotic rats.