Liver Biopsy

Percutaneous liver biopsy is one of the most widely used procedures in hepatology today. Although there are some limitations to the procedure and histologic analysis, there is still no reliable noninvasive alternative. The primary purpose of a biopsy is to confirm the suspected diagnosis, and to quantify the extent of hepatic damage that has occurred. In addition to these indications, occasionally a systemic disease diagnosis is made through liver biopsy. For example, tuberculosis and sarcoidosis are occasionally first diagnosed through histologic assessment and culture of the liver tissue. Likewise, the diagnosis of amyloidosis is often made by liver biopsy. It is still the only definitive way to diagnosis hemochromatosis and fatty liver disease. Medication-induced hepatotoxicity can only be confirmed through liver biopsy, though it may be suspected based on history and enzyme abnormalities.

There are few true contraindications to liver biopsy. Significant coagulopathy with INR > 1.5, platelet count < 60,000, or prolonged PTT should all be corrected prior to percutaneous biopsy. Relative contraindications include ascites, large hemangiomas, and intra-abdominal infections. Patient compliance is critically important, and those not willing to cooperate cannot undergo biopsy. In these scenarios, alternative methods such as transvenous routes can be used to obtain tissue.

The technique and instrumentation used for biopsy is one that has continued to evolve over time. Most centers now use disposable needles or guns to reduce costs and accommodate the larger numbers of biopsies being performed. The most commonly practiced technique is outpatient percutaneous biopsy, with or without conscious sedation, followed by an observation and monitoring period of 2 to 6 hours before discharging the patient. Prebiopsy ultrasound has been advocated as a reasonable safety measure to prevent inadvertent puncture of the gallbladder or large intrahepatic blood vessels.

Complications of biopsies include pain, perforation of the gallbladder, colon, kidney or lung, intraabdominal bleeding, infection, pneumothorax, and vasovagal responses. Rarely, an intrahepatic arteriovenous fistula or hemobilia can occur. These generally resolve spontaneously with conservative management. Significant postbiopsy bleeding is evident by hemodynamic changes and pain. Subclinical bleeding when evaluated by imaging is not uncommon, but is of no clinical significance. The incidence of significant bleeding varies by patient population, but in a large cohort of over 9,000 patients undergoing a percutaneous liver biopsy procedure over 20 years at the Mayo clinic, only 0.24% had bleeding, with 0.11% having fatal bleeding. In a more recent evaluation of bleeding risk factors, biopsy-related bleeding occurred in 1.6% of 629 patients that had liver biopsies. Biopsy-related mortality was surprisingly high at 0.48%, but this was found to be the case in those with mycobacterial infections, thrombo-cytopenia, recent heparin administration, and advanced cirrhosis. In another recent review of 861 biopsies, the overall incidence of significant complication, including bleeding, pneumothorax, and severe hypotension was 1.4%. The majority of these occurred again in the setting of cirrhosis. A gelfoam plug can be used in settings of mild coagu-lopathy or ascites with apparent reasonable safety, but is not widely practiced. In settings where a percutaneous biopsy is deemed unsafe, a transvenous, typically tran-sjugular biopsy can be performed by an interventional radiologist. This procedure was recently analyzed at a single center. Over an 80-month period, 371 patients had 410 attempted biopsies, with a mean of 3.4 needle passes per procedure. A tissue diagnosis was achieved in 98%, with 6 samples being too small to analyze. There were 10 (2.4%) complications, including 3 intraperitoneal bleeds and 1 death. Overall, it is a safe procedure if performed in a center with a high level of experience and expertise.

The ability to assess histologic aspects of liver disease has been a vital tool in our understanding of the natural history and pathogenesis of many disorders. Although accurate and reproducible, biopsy sampling error does exist, and has been shown to be as high as 30% in terms of minor differences in inflammation and fibrosis. This is also partially determined by the size of the core of tissue obtained and the number of portal tracts seen in the specimen. Still, it is considered the gold standard, and to date, there are no alternative markers of inflammation or fibrosis that have gained widespread use. There are commercially available test kits of fibrosis currently available on the market for use in viral hepatitis, including: (1) FibroSpect (Prometheus Labs, San Diego) and (2) FibroTest (BioPredictive, France; FibroSURE, LabCorp, USA). However, the limitation with both is a lack of optimal sensitivity when little fibrosis is present. Further testing and modification is necessary before these modalities can replace liver biopsies. Their current utility is predominantly in a research setting or in clinical practice where liver biopsies cannot be done.

Constipation Prescription

Constipation Prescription

Did you ever think feeling angry and irritable could be a symptom of constipation? A horrible fullness and pressing sharp pains against the bladders can’t help but affect your mood. Sometimes you just want everyone to leave you alone and sleep to escape the pain. It is virtually impossible to be constipated and keep a sunny disposition. Follow the steps in this guide to alleviate constipation and lead a happier healthy life.

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