Correspondence

Management of Hepatic Encephalopathy

N Engl J Med 1997; 337:1921-1922December 25, 1997

Article

To the Editor:

In their review, Riordan and Williams (Aug. 14 issue)1 state that protein restriction is a well-documented therapy for hepatic encephalopathy and imply that a high dietary protein intake is a common cause of hepatic encephalopathy in patients with liver cirrhosis. To our knowledge, scientific proof of the benefit of protein restriction is lacking, and there are no controlled studies of protein restriction. The authors refer to a chapter in a book2 and an experimental study in dogs.3 They recommend minimal daily protein intakes of 0.8 to 1.0 g per kilogram of body weight to maintain nitrogen balance.

The recent guidelines for nutrition in liver disease and transplantation of the European Society of Parenteral and Enteral Nutrition recommend protein in amounts of 1.0 to 1.5 g per kilogram per day in patients with chronic liver disease, since protein requirements are higher in patients with cirrhosis than in the general population.4

Malnutrition is common in patients with cirrhosis, and adequate provision of food may improve liver function, clinical outcome, and even survival.4,5 According to some studies, hepatic encephalopathy may even improve with adequate nutrition, including protein.5 The intake should be at the upper end of the range in patients who are malnourished or have an inadequate intake, especially if this is due to concurrent illness. In malnourished patients with liver cirrhosis and hepatic encephalopathy, one should restrict daily protein intake to 0.5 g per kilogram only very transiently and then increase intake to 1.0 to 1.5 g per kilogram per day. If one must restrict protein, supplementation with branched-chain amino acids is recommended to improve nitrogen balance. There is no evidence that the prophylactic restriction of protein will postpone the first episode of encephalopathy.

We urge that the clinical suspicion of possible intolerance of dietary protein be balanced against the increasing evidence that adequate nutrition, including fair amounts of protein, can improve clinical outcome in patients with hepatic encephalopathy.

Mathias Plauth, M.D.
Humboldt Universität zu Berlin, D-10098 Berlin, Germany

Manuela Merli, M.D.
Università di Roma La Sapienza, I-00185 Rome, Italy

Jens Kondrup, M.D., Ph.D.
Rigshopitalet, DK-2100 Copenhagen, Denmark

5 References

1. 1

   Riordan SM, Williams R. Treatment of hepatic encephalopathy. N Engl J Med 1997;337:473-479
   Full Text | Web of Science | Medline

2. 2

   Uribe M, Conn HO. Dietary management of portal-systemic encephalopathy. In: Conn HO, Bircher J, eds. Hepatic encephalopathy: syndromes and therapies. Bloomington, Ill.: Medi-Ed Press, 1994:331-49.
   

3. 3

   Balo J, Korpassy B. The encephalitis of dogs with Eck fistula fed on meat. Arch Pathol 1932;13:80-87
   Web of Science

4. 4

   Plauth M, Merli M, Kondrup J, Weimann A, Ferenci P, Muller MJ. ESPEN guidelines for nutrition in liver disease and transplantation. Clin Nutr 1997;16:43-55
   CrossRef | Web of Science | Medline

5. 5

   Kondrup J, Muller MJ. Energy and protein requirements of patients with chronic liver disease. J Hepatol 1997;27:239-247
   CrossRef | Web of Science | Medline

Author/Editor Response

The authors reply:

To the Editor: Protein-energy malnutrition, as defined on the basis of anthropometric criteria, is present in 20 to 60 percent of patients with cirrhosis1 and is associated with both an increased prevalence of complications and an increased mortality rate.2 Although such patients require adequate protein intake to improve their nutritional status, increasing quantities of protein precipitate or exacerbate hepatic encephalopathy in 35 percent of patients with a background of this disorder,3 highlighting the nutritional dilemma often confronted by clinicians in this situation. Patients with cirrhosis require daily protein intakes of at least 0.8 to 1.0 g per kilogram to achieve a positive nitrogen balance. In keeping with the recommendations of the European Society for Parenteral and Enteral Nutrition consensus group,4 long-term restriction of daily protein intake to less than 1 g per kilogram should be avoided, even in those with a history of hepatic encephalopathy.5

In practical terms, after temporary restriction of protein intake to 20 g per day at the onset of an acute episode or exacerbation of hepatic encephalopathy, daily intake should be increased by 10 g every three to five days until the individual protein tolerance has been established. Preparations of branched-chain amino acids have a specific role in improving nitrogen balance in malnourished patients with cirrhosis, a history of hepatic encephalopathy, and a daily protein intake of less than 1 g per kilogram who cannot tolerate protein supplementation by other means, including the use of vegetable protein or standard preparations of synthetic amino acids.5 Protein restriction should not be instituted in patients with cirrhosis without a history of hepatic encephalopathy.

Stephen M. Riordan, M.D.
Roger Williams, M.D.
University College London Medical School, London WC1E 6HX, United Kingdom

5 References

1. 1

   Italian Multicentre Cooperative Project on Nutrition in Liver Cirrhosis. Nutritional status in cirrhosis. J Hepatol 1994;21:317-325
   CrossRef | Web of Science | Medline

2. 2

   Lautz HU, Selberg O, Korber J, Burger M, Muller MJ. Protein-calorie malnutrition in liver cirrhosis. Clin Investig 1992;70:478-486
   CrossRef | Medline

3. 3

   Horst D, Grace ND, Conn HO, et al. Comparison of dietary protein with an oral, branched chain-enriched amino acid supplement in chronic portal-systemic encephalopathy: a randomized controlled trial. Hepatology 1984;4:279-287
   CrossRef | Web of Science | Medline

4. 4

   Plauth M, Merli M, Kondrup J, Weimann A, Ferenci P, Muller MJ. ESPEN guidelines for nutrition in liver disease and transplantation. Clin Nutr 1997;16:43-55
   CrossRef | Web of Science | Medline

5. 5

   Riordan SM, Williams R. Treatment of hepatic encephalopathy. N Engl J Med 1997;337:473-479
   Full Text | Web of Science | Medline

Citing Articles (6)

Citing Articles

1. 1

   Manuela Merli, Oliviero Riggio. (2009) Dietary and nutritional indications in hepatic encephalopathy. Metabolic Brain Disease 24:1, 211-221
   CrossRef

2. 2

   Ronnie E. Mathews, Brendan M. McGuire, Carlos A. Estrada. (2006) Outpatient Management of Cirrhosis: A Narrative Review. Southern Medical Journal 99:6, 600-606
   CrossRef

3. 3

   Jens Kondrup. (2006) Nutrition in end stage liver disease. Best Practice & Research Clinical Gastroenterology 20:3, 547-560
   CrossRef

4. 4

   Pratima Sharma, Hugo E. Vargas, Jorge Rakela. 2005. Monitoring and Care of the Patient Before Liver Transplantation. , 473-489.
   CrossRef

5. 5

   M. Durán Tabernes, J. Córdoba Cardona. (2004) Encefalopatía hepática. Medicine - Programa de Formación Médica Continuada Acreditado 9:8, 513-520
   CrossRef

6. 6

   Barry A Mizock. (1999) Nutritional support in hepatic encephalopathy. Nutrition 15:3, 220-228
   CrossRef