Liver transplantation for mitochondrial respiratory chain disorders: to be or not to be?

Acute Liver Failure in Children

“Acute liver failure” (ALF) and “fulminant liver failure” are terms used interchangeably to describe severe and sudden onset of liver cell dysfunction leading on to synthetic and detoxification failure across all age groups. Considerable variations exist between ALF in children and adults, in terms of aetiology and prognosis. Encephalopathy is not essential to make a diagnosis of ALF in children but when present has a bad prognosis. Early recognition of ALF and initiation of supportive management improve the outcome. Liver transplantation remains the only definitive treatment when supportive medical management fails.

Drug management in emergent liver transplantation of mitochondrial disorder carriers: review of the literature

BACKGROUND

Mitochondrial respiratory-chain disorders (MRCD) lead to progressive disabling of neurological and cellular conditions that involve muscles, brain, kidney, and liver dysfunction. Affected individuals may need surgery, including orthotopic liver transplantation (OLT). Surgery poses anesthesia challenges because of the prolonged use of anesthetic drugs and sedatives, which may inhibit oxidative phosphorylation, mimic mitochondrial cytopathic disorders, or unveil them ex novo.

MATERIALS AND METHODS

We conducted a multilingual PubMed search of surgical and non-surgical anesthesia reports between the years 1992 and 2008, where anesthetic drugs were used in MRCD patients, especially for those undergoing urgent OLTs.

RESULTS

There were 51 case reports of 210 anesthesia and critical care interventions in patients with MRCD, a large part of them were children. Data pertaining to the safe usage of anesthesia and perioperative drugs were limited and conflicting. We found no article that addressed the issue of perioperative handling of urgent OLT in MRCD patients. We therefore suggest our own - although limited - experience for such occasions.

CONCLUSION

There are no randomized, controlled, trial-based indications regarding safe anesthetic drugs to be used perioperatively in MRCD carriers. Consultation among geneticists, anesthesiologists, intensivists, and surgeons is essential in patients with known/suspected metabolic syndrome for planning appropriate perioperative care.

Liver Transplantation for Inborn Errors of Metabolism

Liver transplantation (LT) has become an accepted treatment for various hepatic-based metabolic disorders. For diseases with hepatic origin but mainly extrahepatic manifestations, it can be regarded as a means of gene therapy. Depending on the underlying disease, optimal dietary and medicamentous treatment cannot reliably prevent periods of metabolic decompensation resulting in severe organ damage. In severe neonatal forms of urea cycle disorders, liver transplantation should be considered in early infancy. The same applies to propionic acidemia, although severe perioperative complications have been described. In methylmalonic aciduria, there is no consensus whether LT alone is prior to combined liver and kidney transplantation (LKT). Moreover, late neurologic complications can occur in some patients with propionic and methylmalonic acidemias. LT as well as LKT is discussed in primary hyperoxaluria. For patients with cystic fibrosis and biliary cirrhosis, LT has become an established treatment that may even improve pulmonary function. Careful individual decisions must be made in patients with mitochondrial disorders because of possible progressive neuromuscular involvement. In most hepatic-based metabolic disorders, restoration of only about 10% of the original enzyme activity is sufficient to warrant sufficient metabolic control.

Etiology, outcome and prognostic indicators of childhood fulminant hepatic failure in the United kingdom

OBJECTIVE

To study the etiology, outcome and prognostic indicators in children with fulminant hepatic failure in the United Kingdom.

DESIGN

Retrospective review of all patients <17 years with fulminant hepatic failure from 1991 to 2000. Fulminant hepatic failure was defined as presence of coagulopathy (prothrombin time >24 seconds or International Normalized Ratio >2.0) with or without hepatic encephalopathy within 8 weeks of the onset of symptoms.

SETTING

Liver Unit, Birmingham Children's Hospital, United Kingdom.

RESULTS

Ninety-seven children (48 male, 49 female; median age, 27 months; range, 1 day-192.0 months) were identified with fulminant hepatic failure. The etiologies were: 22 metabolic, 53 infectious, 19 drug-induced, and 3 autoimmune hepatitis. The overall survival rate was 61%. 33% (32/97) recovered spontaneously with supportive management. Fifty-five children were assessed for liver transplantation. Four were unstable and were not listed for liver transplantation; 11 died while awaiting liver transplantation. Liver transplantation was contraindicated in 10 children. Of the 40 children who underwent liver transplantation, 27 survived. Children with autoimmune hepatitis, paracetamol overdose or hepatitis A were more likely to survive without liver transplantation. Children who had a delay between the first symptom of liver disease and the onset of hepatic encephalopathy (median, 10.5 days versus 3.5 days), higher plasma bilirubin (299 micromol/L versus 80 micromol/L), higher prothrombin time (62 seconds versus 40 seconds) or lower alanine aminotransferase (1288 IU/L versus 2929 IU/L) levels on admission were more likely to die of fulminant hepatic failure or require liver transplantation (P < 0.05). On multivariate analysis, the significant independent predictors for the eventual failure of conservative therapy were time to onset of hepatic encephalopathy >7 days, prothrombin time >55 seconds and alanine aminotransferase </=2384 IU/L on admission.

CONCLUSIONS

Children with fulminant hepatic failure with severe coagulopathy, lower alanine aminotransferase on admission and prolonged duration of illness before the onset of hepatic encephalopathy are more likely to require liver transplantation. Early referral to a specialized center for consideration of liver transplantation is vital.