Background
Heavy alcohol consumption causes alcoholic liver disease and may lead to a number of other concomitant diseases. Alcohol may damage the function of body organs and can cause cancer. Liver damage due to excessive alcohol consumption is usually presented as fatty liver (build-up of fats in the liver), steatohepatitis (inflammation of the liver with concurrent fat accumulation in the liver), fibrosis (fibrous degeneration), alcoholic cirrhosis (scarring of the liver), and hepatocellular carcinoma (most common type of liver cancer). When liver fibrosis progresses, alcoholic cirrhosis occurs.
Abstinence from alcohol may help people with alcoholic disease to improve their health at any stage of their disease; however, the more advanced the stage, the higher the risk of complications, co-morbidities (presence of other diseases), and mortality (death), and lesser the effect of abstinence. Abstinence from alcohol one month after diagnosis of early cirrhosis will improve the chance of a seven-year life expectancy by 1.6 times. Liver transplantation (replacement of a diseased liver) is the only radical method that may change the prognosis of a person with alcoholic liver disease; however, besides the difficulties of finding a suitable liver transplant organ, there are many other factors that may influence a person's survival after transplantation.
Ultrasound is an inexpensive method that has been used for years in clinical practice to diagnose alcoholic cirrhosis. Ultrasound parameters for assessing cirrhosis in people with alcoholic liver disease encompass among others liver size, bluntness of the liver edge, coarseness of the liver parenchyma (part of the liver that filters blood to remove toxins), nodularity (unevenness) of the liver surface, size of the lymph nodes (small glands that filter lymph) around the hepatic artery (which supplies oxygenated blood to the liver), irregularity and narrowness of the inferior vena cava (which carries blood from the lower body to the heart), portal vein velocity, and spleen size.
Diagnosis of cirrhosis by ultrasound, especially in people who have no symptoms, may have its advantages for the prognosis, motivation, and treatment of these people to decrease their alcohol consumption or become abstinent.
Timely diagnosis of alcoholic cirrhosis in people with alcoholic liver disease is important for evaluation of prognosis or choosing treatment strategies.
Aim
The primary review aim was to determine the diagnostic accuracy of ultrasound for detecting the presence or absence of cirrhosis in people with alcoholic liver disease compared with liver biopsy (where a small needle is inserted into the liver to collect a sample, which is then examined in a laboratory) as reference standard (i.e., the best available test). The secondary aim of the review was to determine the diagnostic accuracy of any of the ultrasound tests, B-mode (a two-dimensional ultrasound image display composed of bright dots representing the ultrasound echoes) or echo-colour Doppler ultrasound (a colour ultrasound image showing blood flow through the liver), used singly or combined, or plus ultrasound signs, or a combination of these, for detecting hepatic cirrhosis in people with alcoholic liver disease compared with liver biopsy as a reference standard.
Methods
We searched the medical literature to retrieve studies for the review to 8 January 2015.
Results
We identified two studies; one from 1985, performed in France, and the other from 2013, performed in South Korea. We could not analyse the data as the two studies with 205 participants in total were very different and they shared only a few clinical signs and symptoms for assessment of cirrhosis. We considered the studies at high risk of bias (the quality of the evidence was low).
Funding
One of the two studies was sponsored by a grant from the Ministry of Health and Welfare, Republic of Korea.
Conclusions
The review authors cannot recommend the use of ultrasound as a diagnostic tool for liver cirrhosis in people with alcoholic liver disease as the obtained study data were insufficient for analysis. Diagnostic ultrasound prospective studies with a large number of people and similar signs and features on ultrasound imaging are needed to establish how good the test is in detecting cirrhosis in people with alcoholic liver disease.
As the accuracy of ultrasonography in the two included studies was not informative enough, we could not recommend the use of ultrasonography as a diagnostic tool for liver cirrhosis in people with alcoholic liver disease. In order to be able to answer the review questions, we need diagnostic ultrasonography prospective studies of adequate sample size, enrolling only participants with alcoholic liver disease.
The design and report of the studies should follow the Standards for Reporting of Diagnostic Accuracy. The sonographic features, with validated cut-offs, which may help identify clinical signs used for diagnosis of fibrosis in alcoholic liver disease, should be carefully selected to achieve maximum diagnostic accuracy on ultrasonography.
Heavy alcohol consumption causes alcoholic liver disease and is a causal factor of many types of liver injuries and concomitant diseases. It is a true systemic disease that may damage the digestive tract, the nervous system, the heart and vascular system, the bone and skeletal muscle system, and the endocrine and immune system, and can lead to cancer. Liver damage in turn, can present as multiple alcoholic liver diseases, including fatty liver, steatohepatitis, fibrosis, alcoholic cirrhosis, and hepatocellular carcinoma, with presence or absence of hepatitis B or C virus infection. There are three scarring types (fibrosis) that are most commonly found in alcoholic liver disease: centrilobular scarring, pericellular fibrosis, and periportal fibrosis. When liver fibrosis progresses, alcoholic cirrhosis occurs. Hepatocellular carcinoma occurs in 5% to 15% of people with alcoholic cirrhosis, but people in whom hepatocellular carcinoma has developed are often co-infected with hepatitis B or C virus.
Abstinence from alcohol may help people with alcoholic disease in improving their prognosis of survival at any stage of their disease; however, the more advanced the stage, the higher the risk of complications, co-morbidities, and mortality, and lesser the effect of abstinence. Being abstinent one month after diagnosis of early cirrhosis will improve the chance of a seven-year life expectancy by 1.6 times. Liver transplantation is the only radical method that may change the prognosis of a person with alcoholic liver disease; however, besides the difficulties of finding a suitable liver transplant organ, there are many other factors that may influence a person's survival.
Ultrasound is an inexpensive method that has been used for years in clinical practice to diagnose alcoholic cirrhosis. Ultrasound parameters for assessing cirrhosis in people with alcoholic liver disease encompass among others liver size, bluntness of the liver edge, coarseness of the liver parenchyma, nodularity of the liver surface, size of the lymph nodes around the hepatic artery, irregularity and narrowness of the inferior vena cava, portal vein velocity, and spleen size.
Diagnosis of cirrhosis by ultrasound, especially in people who are asymptomatic, may have its advantages for the prognosis, motivation, and treatment of these people to decrease their alcohol consumption or become abstinent.
Timely diagnosis of alcoholic cirrhosis in people with alcoholic liver disease is the cornerstone for evaluation of prognosis or choosing treatment strategies.
To determine the diagnostic accuracy of ultrasonography for detecting the presence or absence of cirrhosis in people with alcoholic liver disease compared with liver biopsy as reference standard.
To determine the diagnostic accuracy of any of the ultrasonography tests, B-mode or echo-colour Doppler ultrasonography, used singly or combined, or plus ultrasonography signs, or a combination of these, for detecting hepatic cirrhosis in people with alcoholic liver disease compared with liver biopsy as a reference standard, irrespective of sequence.
We performed searches in The Cochrane Hepato-Biliary Group Controlled Trials Register, The Cochrane Hepato-Biliary Group Diagnostic Test Accuracy Studies Register, The Cochrane Library (Wiley), MEDLINE (OvidSP), EMBASE (OvidSP), and the Science Citation Index Expanded to 8 January 2015. We applied no language limitations.
We screened study references of the retrieved studies to identify other potentially relevant studies for inclusion in the review and read abstract and poster publications.
Three review authors independently identified studies for possible inclusion in the review. We excluded references not fulfilling the inclusion criteria of the review protocol. We sent e-mails to study authors.
The included studies had to evaluate ultrasound in the diagnosis of hepatic cirrhosis using only liver biopsy as the reference standard.
The maximum time interval of investigation with liver biopsy and ultrasonography should not have exceeded six months. In addition, ultrasonography could have been performed before or after liver biopsy.
We followed the Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy.
The review included two studies that provided numerical data regarding alcoholic cirrhosis in 205 men and women with alcoholic liver disease. Although there were no applicability concerns in terms of participant selection, index text, and reference standard, we judged the two studies at high risk of bias. Participants in both studies had undergone both liver biopsy and ultrasonography investigations. The studies shared only a few comparable clinical signs and symptoms (index tests).
We decided to not perform a meta-analysis due to the high risk of bias and the high degree of heterogeneity of the included studies.