Idiosyncratic liver injury: challenges and approaches

Clinical presentations of drug-induced liver injury (DILI) cover essentially the entire spectrum of known liver diseases. However, in the last 8 years the form of liver injury that has most frequently resulted in labeling restrictions is idiosyncratic hepatocellular injury leading to acute liver failure. This rare form of DILI has a characteristic clinical presentation that includes an acute onset after uneventful treatment with drug for weeks to months. Serum alanine aminotransferase rises to very high levels and the appearance of jaundice indicates a high mortality even if the therapy is discontinued. Drugs that can cause this type of injury almost always are associated with frequent (2-15% of all treated patients) and minor serum aminotransferase elevations. These elevations are believed to reflect true liver injury, but often reverse even if drug therapy is continued. The bases for this "adaptation" is not known, as is why some patients do not adapt and develop progressive liver injury. Understanding how drugs cause severe idiosyncratic hepatocellular toxicity has been frustrated by the lack of good preclinical models. Indeed, because these events occur so rarely, the vast majority of humans are not good models. Studies of genomic DNA from affected individuals should provide important insight but not the complete answer because environmental factors almost certainly contribute to individual susceptibility. The most fruitful approach may therefore lie in focused and well-controlled phenotype/genotype studies of the rare patients who have survived this type of injury. The National Institute of Diabetes and Digestive and Kidney Diseases of The National Institutes of Health has recently sponsored a cooperative agreement (UO1) to create a Drug Induced Liver Injury Network (DILIN). DILIN consists of University of Michigan, Indiana University, University of Connecticut, University of California, San Francisco, University of North Carolina, and Duke University. This network should provide heretofore missing resources required to address the problem.

The liver in HIV in Africa

As access to antiretroviral therapy improves across the African continent, liver disease is emerging as an important cause of morbidity and mortality among HIV-infected individuals. Although coinfection with hepatitis B virus (HBV) and hepatitis C virus (HCV), along with highly active antiretroviral therapy (HAART)-induced hepatotoxicity appear to be the major causes of liver disease in this population, other diseases endemic to Africa with hepatic manifestations are influenced by HIV infection as well. In this review we present the available data on liver disease in HIV-infected populations in Africa and discuss relevant data from the rest of the world. In addition, we highlight important areas for further study.

Ramipril-associated hepatotoxicity

CONTEXT

Angiotensin-converting enzyme inhibitors are prescribed for many cardiovascular and renal diseases. Adverse hepatic events, especially cholestasis, have rarely been reported with captopril, enalapril, lisinopril, and fosinopril. To date, hepatic injury associated with ramipril has not been reported.

OBJECTIVE

To describe 3 patients who developed hepatitis, with or without jaundice, after receiving ramipril.

DESIGN

Medical records and liver biopsies of the 3 patients were reviewed. Clinical, laboratory, and histologic findings were compared with findings in other cases of angiotensin-converting enzyme inhibitor-induced liver injury reported in the literature.

RESULTS

The 3 patients were middle-aged men. In 2 patients, jaundice appeared 4 and 8 weeks after starting ramipril. Bilirubin levels peaked at 15.5 and 5 mg/dL, and alkaline phosphatase values peaked at 957 and 507 U/L. Aminotransferase levels were mildly elevated. Endoscopic retrograde cholangiopancreatography and ultrasonography showed no bile duct obstruction. Liver biopsies from the jaundiced patients were similar, with cholestasis, duct necrosis, and extravasation of bile, ductular proliferation, and portal inflammation. Cholestasis improved in 1 patient 6 weeks after stopping ramipril and was prolonged for 14 months in the other, in whom biliary cirrhosis was present on biopsy. The third patient developed hepatitis without jaundice 3 weeks after starting ramipril; symptoms resolved after stopping the drug. Ramipril-associated liver injury is similar to that seen with other angiotensin-converting enzyme inhibitors, but liver biopsy findings of duct necrosis and extravasation of bile have not been reported previously.

CONCLUSION

Prolonged cholestatic hepatitis and biliary cirrhosis may result from the use of ramipril. Monitoring of liver enzymes is advisable for patients starting on ramipril.

Minocycline-induced liver injury

Tetracycline may cause fatty infiltration of the liver; more recently, it has been reported to cause intrahepatic cholestasis with bile duct depletion. However, minocycline, a derivative of tetracycline, is not generally recognized to be hepatotoxic. We report a series of six cases of presumed minocycline-induced liver injury; five of these patients had acute hepatitic illness, whereas one had a more prolonged course with histological evidence of chronic hepatitis. In addition, three patients demonstrated abnormal anti-nuclear antibody levels, and one had positive double-stranded DNA.

Chronic active hepatitis and liver cirrhosis in association with combined tamoxifen/tegafur adjuvant therapy

Two female breast cancer patients who received combined tamoxifen and tegafur as postsurgical adjuvant therapy developed severe hepatotoxicity after being treated for three and eight months, respectively. Shortly after the cessation of the treatment, routine liver tests showed gradual recovery, but liver biopsies revealed chronic active hepatitis in one patient and liver cirrhosis in the other. Four and five years, respectively, after the cessation of the treatment, the results of liver tests were normal and distinct histological improvement was observed in both patients. Because these patients had no viral and immunoserological markers nor any history of alcohol abuse, this study suggested that the tamoxifen and tegafur regimen induced reversible chronic active liver disease.

Severe chronic active hepatitis induced by UFTR containing tegafur and uracil

A 77-year-old female patients developed severe hepatic injury after the administration of UFTR, which contains tegafur and uracil, for postoperative chemotherapy of colon cancer. Liver damage was recognized 10 months after its administration. Serum markers for viral hepatitis and various autoantibodies were negative. The wedged biopsied liver specimen revealed advanced chronic active hepatitis with periportal confluent necrosis, marked intralobular spotty necrosis, and significant proliferation of pseudo-bile ductules. Although the cessation of the drug and conservative therapies improved hepatic function, an accidental readministration of UFTR caused her severe hepatic damage again. These findings suggest that liver injury in the present case was caused by UFTR. Histological findings were unique. Although tegafur is known to worsen hepatic function when given to patients with liver cirrhosis, UFTR may also cause severe hepatic injury in those without preexisting liver disease.

Severe hepatotoxicity related to benzarone: a report of three cases with two fatalities

We report three cases of severe hepatotoxicity related to benzarone, a benzofuran derivative. Our cases include a 35-year-old woman with (sub)fulminant hepatitis, a 67-year-old woman with macronodular cirrhosis, and a 68-year-old man with severe chronic active hepatitis and cirrhosis, with positivity of anti-smooth muscle antibodies. Two patients died. We stress the potential of benzarone to cause hepatotoxicity, which usually resembles severe chronic active hepatitis. Our cases constitute the most severe cases of benzarone hepatotoxicity reported so far, and comprise the first cases of (sub)fulminant hepatitis and cirrhosis related to benzarone.

[Interferon or C virus-induced autoimmune chronic hepatitis? Report of personal observations and review of the literature]

Chronic persistent hepatitis C in a 35 year-old man treated for nine months with interferon, converted into autoimmune chronic hepatitis. Prior to this conversion, the laboratory cell-integrity parameters of C hepatitis had permanently returned to normal, and HCV RNA had become negative. Prior to the initiation of treatment with interferon, no autoimmune antibodies had been present. On the basis of reports in the literature, the possible pathogenesis of this conversion is discussed, with two major mechanisms being considered: 1. induction of the autoimmune process by interferon, and 2. the "unmasking" of a pre-existing autoimmune process in the later course of chronic virus C hepatitis.

Retinoid hepatitis

A 65-year-old woman treated with etretinate for pityriasis rubra pilaris developed chronic active hepatitis. The elevated transaminases were noted 2 months after initiation of therapy and peaked 2 months after discontinuation of etretinate. The spectrum of liver toxicity induced by etretinate is reviewed. We suggest that reported cases of retinoid-induced liver disease can be divided into four distinct categories: nonspecific reactive hepatitis, acute hepatitis, chronic active hepatitis, and severe fibrosis or cirrhosis.

Diclofenac induced hepatitis. 3 cases with features of autoimmune chronic active hepatitis

Diclofenac is a frequently prescribed nonsteroidal antiinflammatory drug (NSAID). Significant hepatotoxicity related to diclofenac may be more common than previously recognized, as three patients with diclofenac-associated hepatitis were seen by one clinician in a single year. All patients were ANA positive during the hepatitis and had histologic features of chronic active hepatitis. Two had been inappropriately treated with corticosteroids. The third patient presented more acutely with jaundice and symptoms of hepatitis. Two of the patients developed the same hepatic reaction when rechallenged with diclofenac. The third patient was changed to tiaprofenic acid, a NSAID of the same family, and redeveloped evidence of hepatotoxicity. All three were subsequently able to take naproxen without liver dysfunction. Diclofenac-induced liver disease may be misdiagnosed. Twenty-six cases of significant hepatic reactions to diclofenac have been previously reported in the literature and are reviewed. Such hepatic reactions to diclofenac and related NSAIDs may be commoner than realized. Introduction of a NSAID of another class appears to be safe.

Phenytoin-induced chronic hepatitis

Phenytoin has been associated with acute hepatotoxicity. Chronic liver enzyme abnormalities associated with phenytoin have been attributed to enzyme induction. There have been no reports of phenytoin-induced chronic hepatitis. We describe an asymptomatic 52-year-old woman who received phenytoin sodium for 11 years and was found to have elevated serum aminotransferases. Assays for hepatitis A, B, and C were negative. Liver biopsy was performed and showed chronic persistent hepatitis. This documentation of phenytoin-induced chronic persistent hepatitis was proven by histology and its etiology confirmed by drug withdrawal and by rechallenge. Although uncommon, this entity is important to recognize in the differential diagnosis of asymptomatic chronic hepatic enzyme dysfunction.

A fatal case of neuroleptic malignant syndrome

A fatal case of Neuroleptic Malignant Syndrome (NMS) affecting a middle-aged woman is presented. Most of the signs and symptoms described for NMS were present and death occurred three hours after the onset of hyperpyrexia. Laboratory and postmortem findings were non-specific. The uses and risks of Haloperidol and Phenelzine on a patient with severe liver impairment are considered. Finally, the medico-legal implications in the context of sudden unexpected death are mentioned.

Combined nitrofurantoin toxicity to liver and lung

Nitrofurantoin is an antibiotic commonly used for prophylaxis and treatment of urinary tract infections. Pulmonary and hepatic toxicity are rare side effects of this agent. The simultaneous occurrence of pulmonary fibrosis and chronic active hepatitis in a patient undergoing long-term nitrofurantoin therapy is reported. The presence of pulmonary toxicity was evidenced by infiltrates on chest radiographs and impaired diffusion capacity during pulmonary function tests. Prolonged elevation of liver enzyme concentrations together with the presence of increased antibody titers (anti-smooth muscle antibody, antinuclear antibody) was suggestive of chronic hepatitis, a diagnosis corroborated by liver biopsy findings. After discontinuation of nitrofurantoin therapy, the patient had a full recovery. The infiltrates initially found on chest radiographs disappeared, and laboratory parameters normalized without the need for corticosteroid therapy.

[Chronic active hepatitis and possible relationship with immunosuppressive therapy]

A 54-year-old man with Chagas cardiomyopathy that was submitted to a heart transplantation and five months later presented a progressive increase in liver enzymes. Diagnosis of chronic active hepatitis was confirmed by histopathologic studies. A transitory interruption of treatment with azathioprine and the posterior re-introduction of small doses, as well as the use of lesser amounts of cyclosporin-A improved the clinical and laboratory pictures. Despite several investigations the pathogenesis of hepatitis remained undetermined, although some type of drug injury was presumed to be involved. The eventual role of viruses as the primary inciting event could not be completely ruled out.

Acute, reversible hepatic failure associated with methotrexate treatment of rheumatoid arthritis

We describe 2 patients who developed reversible decompensated liver disease while taking pulse dosed methotrexate (MTX) for rheumatoid arthritis. One of the patients was available for biopsy and had chronic active hepatitis--a lesion not previously described with MTX. This appears to be a unique and unusual manifestation of MTX hepatotoxicity.

Chronic active hepatitis associated with diclofenac sodium therapy

Diclofenac sodium (Voltarol, Geigy Pharmaceuticals) is a non-steroidal anti-inflammatory derivative of phenylacetic acid. Although generally well-tolerated, asymptomatic abnormalities of liver function have been recorded and, less commonly, severe hepatitis induced by diclofenac. The patient described developed chronic active hepatitis after six months therapy with diclofenac sodium which progressed despite the withdrawal of the drug, a finding not previously reported.