Clinical, biochemical and imaging-verified regression of hepatitis B-induced cirrhosis

Prediction of liver cirrhosis, using diagnostic imaging tools

Early diagnosis of liver cirrhosis is important. Ultrasound-guided liver biopsy is the gold standard for diagnosis of liver cirrhosis. However, its invasiveness and sampling bias limit the applicability of the method. Basic imaging for the diagnosis of liver cirrhosis has developed over the last few decades, enabling early detection of morphological changes of the liver by ultrasonography (US), computed tomography, and magnetic resonance imaging (MRI). They are also accurate diagnostic methods for advanced liver cirrhosis, for which early diagnosis is difficult. There are a number of ways to compensate for this difficulty, including texture analysis to more closely identify the homogeneity of hepatic parenchyma, elastography to measure the stiffness and elasticity of the liver, and perfusion studies to determine the blood flow volume, transit time, and velocity. Amongst these methods, elastography using US and MRI was found to be slightly easier, faster, and able to provide an accurate diagnosis. Early diagnosis of liver cirrhosis using MRI or US elastography is therefore a realistic alternative, but further research is still needed.

Reversal of hepatic fibrosis: pathophysiological basis of antifibrotic therapies

Chronic liver injuries of different etiologies eventually lead to fibrosis, a scarring process associated with increased and altered deposition of extracellular matrix in the liver. Progression of fibrosis has a major worldwide clinical impact due to the high number of patients affected by chronic liver disease which can lead to severe complications, expensive treatment, a possible need for liver transplantation, and death. Liver fibrogenesis is characterized by activation of hepatic stellate cells and other extracellular matrix producing cells. Liver fibrosis may regress following specific therapeutic interventions. Other than removing agents causing chronic liver damage, no antifibrotic drug is currently available in clinical practice. The extent of liver fibrosis is variable between individuals, even after controlling for exogenous factors. Thus, host genetic factors are considered to play an important role in the process of liver scarring. Until recently it was believed that this process was irreversible. However, emerging experimental and clinical evidence is starting to show that even cirrhosis in its early stages is potentially reversible.

Reversal of hepatic fibrosis: pathophysiological basis of antifibrotic therapies

Chronic liver injuries of different etiologies eventually lead to fibrosis, a scarring process associated with increased and altered deposition of extracellular matrix in the liver. Progression of fibrosis has a major worldwide clinical impact due to the high number of patients affected by chronic liver disease which can lead to severe complications, expensive treatment, a possible need for liver transplantation, and death. Liver fibrogenesis is characterized by activation of hepatic stellate cells and other extracellular matrix producing cells. Liver fibrosis may regress following specific therapeutic interventions. Other than removing agents causing chronic liver damage, no antifibrotic drug is currently available in clinical practice. The extent of liver fibrosis is variable between individuals, even after controlling for exogenous factors. Thus, host genetic factors are considered to play an important role in the process of liver scarring. Until recently it was believed that this process was irreversible. However, emerging experimental and clinical evidence is starting to show that even cirrhosis in its early stages is potentially reversible.

Fibrosis and cirrhosis reversibility - molecular mechanisms

The concept that liver fibrosis is a dynamic process with potential for regression as well as progression has emerged in parallel with clinical evidence for remodeling of fibrotic extracellular matrix in patients who can be effectively treated for their underlying cause of liver disease. This article reviews recent discoveries relating to the cellular and molecular mechanisms that regulate fibrosis regression, with emphasis on studies that have used experimental in vivo models of liver disease. Apoptosis of hepatic myofibroblasts is discussed. The functions played by transcription factors, receptor-ligand interactions, and cell-matrix interactions as regulators of the lifespan of hepatic myofibroblasts are considered, as are the therapeutic opportunities for modulating these functions. Growth factors, proteolytic enzymes, and their inhibitors are discussed in detail.

Schistosomiasis and hepatic fibrosis regression

Manson schistosomiasis is an important cause of hepatic fibrosis, a consequence of the highly fibrogenic nature of the mature schistosome eggs, the main pathogenetic factor of that disease. Thus, students interested on schistosomiasis are to be also interested on the subject of fibrosis formation and degradation since the very beginning of their studies. A brief review of the studies directly related to such interest is presented here to stress the progress obtained, and to point out to the need of further research.

Palmar erythema

Palmar erythema (PE), an often overlooked physical finding, is due to several physiologic or systemic pathologic states. PE can exist as a primary physiologic finding or as a secondary marker of systemic pathology. Primary or physiologic PE can be due to heredity, occurs in at least 30% of pregnant women as a result of associated alterations in the function of the skin and its microvasculature, or may be a diagnosis of exclusion (i.e. idiopathic PE). Secondary PE from systemic pathology encompasses a wide range of disease states. Twenty-three percent of patients with liver cirrhosis, from varying causes, can manifest PE as a result of abnormal serum estradiol levels. Patients with a rare neonatal liver disease such as Wilson disease and hereditary hemochromatosis may exhibit PE along with the other systemic manifestations of the genodermatoses. PE has been reported to occur in >60% of patients with rheumatoid arthritis and is associated with a favorable prognosis. Up to 18% of patients with thyrotoxicosis and 4.1% of patients with diabetes mellitus can have PE. This cutaneous manifestation of diabetes occurs more often than the more classic diseases such as necrobiosis lipoidica diabeticorum (0.6%). PE can be seen in early gestational syphilis and among patients with human T-lymphotrophic virus-1-associated myelopathy. Drug-induced PE with hepatic damage has been documented with use of amiodarone, gemfibrozil, and cholestyramine, while topiramate and albuterol (salbutamol) have been reported to cause PE in the setting of normal liver function. Fifteen percent of patients with both metastatic and primary brain neoplasms may have PE. Increased levels of angiogenic factors and estrogens from solid tumors have been postulated as the cause of PE in such cases. Erythema ab igne can mimic PE, and patients with atopic diathesis are more likely to have PE than matched control subjects. Smoking and chronic mercury poisoning are environmental causes of PE.No treatment of primary PE is indicated. If medication is the cause of PE, the drug responsible should be discontinued if possible. Identification of PE related to underlying disorders should be followed by treatment of the underlying condition. In light of the numerous etiologies of PE, this article reviews the current literature and provides a framework to help guide the clinician in determining the cause of PE in patients presenting with this finding.

Remodeling of hepatic vascular changes after specific chemotherapy of schistosomal periportal fibrosis

Hepatosplenic schistosomiasis was the first human disease in which the possibility of extensive long standing hepatic fibrosis being degraded and removed has been demonstrated. When such changes occurred, the main signs of portal hypertension (splenomegaly, esophageal varices) progressively disappeared, implying that a profound vascular remodeling was concomitantly occurring. Hepatic vascular alterations associated with advanced schistosomiasis have already been investigated. Obstruction of the intrahepatic portal vein branches, plus marked angiogenesis and compensatory hyperplasia and hypertrophy of the arterial tree are the main changes present. However, there are no data revealing how these vascular changes behave during the process of fibrosis regression. Here the mouse model of pipestem fibrosis was used in an investigation about these vascular alterations during the course of the infection, and also after treatment and cure of the disease. Animals representing the two polar hepatic forms of the infection were included: (1) "isolated granulomas" characterized by isolated periovular granulomas sparsely distributed throughout the hepatica parenchyma; and (2) 'pipestem fibrosis' with periovular granulomas and fibrosis being concentrated within portal spaces, before and after treatment, were studied by means of histological and vascular injection-corrosion techniques. Instances of widespread portal vein obstruction of several types were commonly found in the livers of the untreated animals. These obstructive lesions were soon repaired, and completely disappeared four months following specific treatment of schistosomiasis. Treatment was accomplished by the simultaneous administration of praziquantel and oxamniquine. The most impressive results were revealed by the technique of injection of colored masses into the portal system, followed by corrosion in strong acid. The vascular lesions of non-treated pipestem fibrosis were represented in the plastic casts by considerable diminution of the fine peripheral portal vein radicles, plus dilatation of periportal collaterals. Four months after treatment, this last picture appeared replaced by tufts of newly interwoven vessels formed along the main portal vein branches, disclosing a strong angiomatoid reparative change. Understanding about the cellular elements at play during fibro-vascular repairing changes of hepatic schistosomiasis represents a matter of considerable scientific and conceptual importance. At present time one may only speculate about the participation of some type of natural stem-cell capable of restoring the diseased liver back to normal once the cause of the disorder has been eliminated.

[Regression of hepatic fibrosis]

Extensive and persistent hepatic fibrosis has for a long time been considered irreversible. However, recent studies on the behavior of hepatic fibrosis, especially those related to evolution and involution of advanced schistosomiasis in man, have challenged this concept, and nowadays it is becoming clear that any type of fibrosis is reversible, including that associated with hepatic cirrhosis. The problem consists in identifying and eliminating its cause. Although fibrosis in the liver has little functional significance by itself, its severity derives from associated vascular changes. However, new data on fibrosis regression indicate that disappearance of fibrosis is usually accompanied by remodeling of vascular changes. But, there are peculiarities related to the anatomic type of fibrosis and to its functional significance, which suggest that sometimes fibrosis may indeed be irreversible. These aspects, some of which in need of further studies, are presented and discussed herein.

Morphological signs of cirrhosis regression

Regression of hepatic cirrhosis is a controversial issue. Recently, a list of histopathological features, observed in human material, was suggested as a hallmark of cirrhosis in the process of regression. An investigation for the presence of these morphologic features was performed at monthly intervals in rats with proved carbon tetrachloride (CCl4)-induced cirrhosis over a period of 9 months following discontinuation of treatment, using sequential liver biopsies. Within the first 4 months, features of the "hepatic repair complex" were identified, together with the enlargement of the hepatic nodules and thinning of the fibrous septa. Subsequent to the 4 months, the histological picture, composed of large and inconspicuous nodules and delimited by thin and frequently incomplete fibrous septa "incomplete septal cirrhosis", appeared to be stabilized. These fibrous septa, when injected with India ink from the portal trunk, presented blood vessels that were seen to drain directly into the sinusoids. These findings suggested that when the cause of cirrhosis is removed, the liver may adapt itself to a new and permanent structure, probably compatible with normal or near-normal function, which may render hepatic cirrhosis clinically, although not morphologically, reversible.