East meets West: acute liver failure in the global village

Hepatic Failure

The progression of liver disease can cause several physiologic derangements that may precipitate hepatic failure and require admission to an intensive care unit. The underlying pathology may be acute, acute-on chronic, or chronic in nature. Liver failure may manifest with a variety of clinical signs and symptoms that need prompt attention. The compromised synthetic and metabolic activity of the failing liver affects all organ systems, from neurologic to integumentary. Supportive care and specific therapies should be instituted in order to improve outcome and minimize time of recovery.

In this chapter we will discuss the definition, clinical manifestations, workup, and management of acute and chronic liver failure and the general principles of treatment of these patients. Management of liver failure secondary to certain common etiologies will also be presented. Finally, liver transplantation and alternative therapies will also be discussed.

A 20-year single-center experience with acute liver failure during pregnancy: is the prognosis really worse?

Pregnant patients with acute liver failure (ALF) are believed to have a worse outcome than nonpregnant women and men with ALF. However objective data supporting this supposition are scant. Therefore, the current study compared the outcome, complications, and causes of ALF among pregnant women and girls with age-matched nonpregnant women and girls and men and boys with ALF. One thousand fifteen consecutive ALF patients in the reproductive age group, admitted at the All India Institute of Medical Sciences, New Delhi, from January 1986 to December 2006, were included in the study. A total of 249 (38.5%) women were pregnant. They were compared with 341 nonpregnant women and girls and 425 men and boys, aged 15 to 45 years. The mortality rate of pregnant women and girls (53.8%) was similar to age-matched nonpregnant women and girls (57.2%), and men and boys (57.9%); P = 0.572. The clinical and biochemical features, disease severity, and complications were also similar in the three groups. A significantly higher proportion of ALF was attributable to hepatitis E virus (HEV) among women and girls who were pregnant (59.4%), as compared with both nonpregnant women and girls (30.4%), and men and boys (23.1%); P < 0.001. However, the outcome of HEV-related ALF was independent of the sex and pregnancy status of the patients (P = 0.103). Mortality in HEV-ALF and non-HEV-ALF patients in pregnant women and girls was 51% (74/145) and 54.7% (52/95)(P > 0.1), respectively. The outcome of pregnant ALF patients was also unrelated to the trimester of pregnancy. The mortality of non-HEV-related ALF among the pregnant women and girls (54.7%), age-matched nonpregnant women and girls (61.7%), and men and boys (62.8%) were also similar (P > 0.1).

CONCLUSION

The mortality of pregnant patients with ALF is similar to that of nonpregnant women and girls and men and boys and is independent of the cause or trimester. Pregnancy per se should not be regarded as a poor prognostic factor for a patient with ALF.

Differential diagnosis of acute liver failure in India

BACKGROUND

Acute liver failure (ALF) is a condition with rapid deterioration of liver function resulting in hepatic encephalopathy and/or coagulopathy in patients with previously normal liver. Complicated forms of certain infectious diseases like falciparum malaria, leptospirosis, dengue fever, ricketsial fever, typhoid fever, haemophagocytosis, herpes simplex virus, cytomegalovirus, tuberculosis or amoebic liver abscess can present with altered mentation and/or bleeding manifestations in presence of jaundice and mimic ALF due to acute viral hepatitis (AVH).

METHODS

We describe our experience in last 2 years with 28 patients of ALF due to above mentioned conditions (ALF-ID) and compared them with 28 patients with ALF due to AVH (ALF-AVH).

RESULTS

In ALF-ID, typhoid fever was present in 1, haemophagocytosis in 1, ricketsial infection in 4 (scrub typhus = 2, endemic typhus = 2), amoebic liver abscess in 4, leptospirosis in 5, dengue fever in 5 and falciparum malaria in 8 patients. In ALF-AVH, hepatitis E and B co-infection was responsible in 1, hepatitis A and E co-infection in 1 and hepatitis E, B and C co-infection in 1, hepatitis E in 18, hepatitis A in 2 and hepatitis B in 5 patients. Differentiation of various forms of ALF-ID from ALF-AVH depends on various clinical, haematological and biochemical parameters, in addition to specific diagnostic tests. Patients with ALF-AVH had mortality rate of 50% (14/28) and ALF-ID had mortality rate of 25% (7/28).

CONCLUSIONS

In developing countries, ALF-mimicking infections should be looked for in differential diagnosis of ALF. Early identification and treatment of these infections is important in reducing mortality.

Acute liver failure: a review

Since publication of the first descriptions of acute liver failure (ALF) as a distinct clinical entity in the 1950's, the understanding of the pathophysiologic mechanisms involved and the management options have increased substantially. ALF still represents a major challenge for todays hepatologists, because it can rapidly lead to multiorgan failure and death that may be preventable with appropriate intervention. This article summarizes the basic patho-physiology underlying ALF, compares epidemiologic trends in the United States, the United Kingdom, and the Far East, and reviews prognostic markers and treatment options for ALF.

Fulminant hepatic failure and the potential role of liver dialysis

Fulminant hepatic failure (FHF) carries a high mortality. We aimed to review the prognostic factors and explore the potential role of Liver Dialysis (LD). Fifty-two patients were reviewed. The etiologies were acetaminophen toxicity (33%), viral hepatitis (18%), autoimmune (10%), idiosyncratic drug reactions (8%), others (6%) and undetermined (25%). Patients with acetaminophen had a significantly higher survival compared to the non-acetaminophen group (p=0.04). Patients with grade 3 encephalopathy had a mortality of 68%, among 5 patients with grade IV encephalopathy, 2 survived and both had had treatment with LD. Chi-square with Fisher's exact test was used for statistical analysis. Our study confirmed that the diagnosis of non-acetaminophen induced FHF and reduced initial serum factor V level are associated with fatal outcome. Timely OLT significantly improved the survival. The role of LD in hepatic regeneration or as a bridge to OLT needs to be further studied with prospective control trials.

The role of cytokines in liver failure and regeneration: potential new molecular therapies

The liver is a unique organ, and first in line, the hepatocytes encounter the potential to proliferate during cell mass loss. This phenomenon is tightly controlled and resembles in some way the embryonal co-inhabitant cell lineage of the liver, the embryonic hematopoietic system. Interestingly, both the liver and hematopoietic cell proliferation and growth are controlled by various growth factors and cytokines. IL-6 and its signaling cascade inside the cells through STAT3 are both significantly important for liver regeneration as well as for hematopoietic cell proliferation. The process of liver regeneration is very complex and is dependent on the etiology and extent of liver damage and the genetic background. In this review we will initially describe the clinical relevant condition, portraying a number of available animal models with an emphasis on the relevance of each one to the human condition of fulminant hepatic failure (FHF). The discussion will then be focused on the role of cytokines in liver failure and regeneration, and suggest potential new therapeutic modalities for FHF. The recent findings on the role of IL-6 in liver regeneration and the activity of the designer IL-6/sIL-6R fusion protein, hyper-IL-6, in particular, suggest that this molecule could significantly enhance liver regeneration in humans, and as such could be a useful treatment for FHF in patients.

Extracorporeal liver perfusion as hepatic assist in acute liver failure: a review of world experience

BACKGROUND

There are almost no prospective, controlled and randomized clinical trials comparing different approaches towards hepatic assist. In order to create a basis for comparing the value of the existing different hepatic assist methods this article offers a systematic review of the world experience with allogeneic or xenogeneic extracorporeal liver perfusion (ECLP).

METHODS

An Internet-assisted search was conducted in the international literature published from 1964 to 2000. Only articles with a clear description of methodology and outcome of patients were included. For multivariate analysis of variance the general linear method (GLM) procedure was used. Differences within the groups were analyzed by chi-square test. Data of 198 patients were included into the statistical analysis for systematic review.

RESULTS

The long-term survival rate (SVR) of these patients was 26%, thus not exceeding published data concerning SVR under standard intensive care. Age below 40 years (P<0.029), coma stage lower than III-IV (P<0.003), total perfusion time over 10 hours (P<0.024), hepatitis B as cause for acute liver failure (ALF) (P<0.05) as well as use of baboon and human livers (P<0.02) were identified as independent positive prognostic markers for improved survival. ECLP as bridging therapy to liver transplantation was successful in 12 of 14 patients.

CONCLUSION

ECLP using pig livers did not surpass the success of conventional intensive care treatment. An additional effect of transgenic expression of human regulators of complement regulation in porcine livers has not yet been proven. ECLP with human livers not suitable for liver transplantation might prove effective and practicable for temporary hepatic support. Bridging to liver transplantation by long-term ECLP using porcine and human livers appears to have comparable efficacy as bioartificial support methods.