
Hepatology
The liver is the largest organ in the body. It weighs nearly 1.5 kg. It is located in the right upper part of the abdomen, under the right ribs and extending to the central and left upper abdomen. The liver has two major lobes the right and the left. The basic functional unit of the liver is known as the lobule. The liver is the metabolic factory of the body and all major metabolic processes needed for life take place in the liver. Carbohydrate, Protein and Fat metabolism takes place here so does the detoxification of unwanted substances as well as the synthesis of a substances needed to sustain life like those needed for immunity.
The prevalence of fatty liver varies between 16- 25% of the general population. Of these nearly 8-10% are going to develop inflammation within the liver (NASH: Non Alcoholic Steato Hepatitis) and 1% are going to develop frank cirrhosis. Alcohol consumption is rising and the major states facing increasing alcohol related diseases are Kerala and Punjab. There are 5 major hepatitis viruses: A, B, C, D and E. Of these A and E are water borne and are spread through contact with contaminated food and water. Whereas B, C and D are blood borne and are spread by needle prick injuries, blood transfusions, dental treatments, dialysis etc. Other relatively rarer causes of liver disease are: Autoimmune Hepatitis (AIH), Primary biliary cirrhosis (PBC) and Primary Sclerosing cholangitis (PSC) diseases of copper (Wilsons disease) and iron (Hemochromatosis) metabolism and liver infections like amebiasis, malaria, Hydatid disease, salmonella etc.
Most Liver diseases, irrespective of the cause pass through the following stages: 1. Acute Hepatitis 2. Chronic Hepatitis 3. Compensated Cirrhosis 4. Decompensated Cirrhosis and 5. Liver Cancer. Acute hepatitis is manifest by deep Jaundice, loss of appetite, lethargy, weakness, nausea and vomiting. The liver tests reveal a high bilirubin and SGOT, SGPT (In thousands). Acute hepatitis can be caused by viruses, drugs and alcohol. It is mostly self-limiting and resolves in a few week, however it may progress to chronic hepatitis if caused by hepatitis B and C. Worsening of Acute hepatitis can lead to acute liver failure. This is a condition which can cause deep jaundice and loss of consciousness and needs to be treated by ICU admission and liver dialysis and may need liver transplantation.
If the liver insult persists for more than 6 months chronic hepatitis sets in. This stage is manifest by persisting lethargy, weakness, nausea, pain in the right upper abdomen and mild jaundice. There is a mild rise in the liver enzymes (reaching hundreds). It is important to treat the patient at this stage because if the liver inflammation persists then cirrhosis is likely to set in, which is irreversible. Both chronic hepatitis B and C can be treated with good results. The primary drugs used for the treatment of chronic hepatitis B are Entecavir and Tenofovir and those for hepatitis C are Sofosbuvir and Velpatsavir.
Cirrhosis is the end stage of all liver diseases whatever may be the cause. It results from repeated episodes of inflammation, scarring and consequent shrinking of the liver. Once the patient develops cirrhosis 24% of patients decompensate in the next 5 years. Decompensation is in the form of Jaundice, Ascites (Fluid in the abdomen), blood vomiting and encephalopathy (changes in consciousness). Decompensated cirrhosis has a poor outcome and has a life expectancy of only 3-5 years. The disease can be cured only with liver transplantation. Patients with decompensated cirrhosis need liver transplantation however conservative management including endoscopic band ligation, and argon plasma coagulation for bleeding, albumin infusions and ascitic tap for taking out abdominal fluid and treatment of renal failure by slow dialysis (SLED), ICU management for the sick patient can all be done to prolong life.
Cirrhosis is a premalignant state. As patients with cirrhosis are now living longer with improved medical management, the incidence of liver cancer in increasing. Cure of liver cancer is dependent on early detection; hence it is necessary to screen all patients with cirrhosis for liver cancer. Liver cancer when detected early can be cured. Surgical treatments include liver resection and liver transplantation. Non-surgical treatments methods are Radiofrequency ablation and acetic acid injection. For larger tumors non curative treatments like transarterial chemoembolization (TACE) and Transarterial radionucide injection (TARE) are available. Chemotherapy has also improved with a number of new agents coming in recent years (Sorefenib, Lenvatinib, Nivolumab etc).
Liver transplantation is the final cure for all patients of decompensated cirrhosis of liver cancer. Transplantation can be cadaveric, DDLT (where the liver is donated by an unrelated donor after brain death) or live related, LDLT (where a part of the liver is donated by a close relative).