Granulomatous hepatitis in a patient receiving carbamazepine

Hepatotoxicity associated with antiepileptic drugs

BACKGROUND

Drug-induced liver injury associated with antiepileptic drugs (AED) is well recognized. The frequency of the most common AED is rare but the consequences can be very serious leading to death or liver transplantation due to acute liver failure induced by these drugs.

CLINICAL FEATURES

Hypersensitivity features are found in more than 70% of patients with phenytoin-induced liver injury, whereas this is only observed in 30% of carbamazepine-associated hepatotoxicity and very rarely with valproate (VPA)-induced liver injury.

PATHOPHYSIOLOGY

The underlying mechanisms behind hepatotoxicity induced by AED are not clear. Reactive metabolites from AED can, in some cases, lead to direct cytotoxicity and liver cell necrosis, whereas in other cases this may lead to neoantigen formation inducing immunoallergic mechanisms.

TREATMENT

No specific therapy is of proved value in severe hepatotoxicity due to AED. However, N-acetylcystein is an appropriate treatment in patients with clinically significant liver injury due to phenytoin and carbamazepine. In patients with VPA-associated liver injury, carnitine that is an important co-factor in the mitochondrial beta-oxidation of fatty acids is the recommended treatment. Early referral of patients with severe liver reactions and coagulopathy to liver transplant centers before encephalopathy can be the difference between liver transplantation and death.

Carbamazepine-provoked hepatotoxicity and possible aetiopathological role of glutathione in the events. Retrospective review of old data and call for new investigation

The antiepileptic drug (AED) carbamazepine is widely used in the treatment of different kinds of seizures as well as affective and behavioural disorders. This paper presents an epidemiological study of carbamazepine-induced hepatic injuries and death, and describes the possible mechanisms of its toxicity. A retrospective analysis of clinical data revealed that the likelihood of hepatic death was comparatively higher in children, particularly when they were receiving medication with multiple AEDs, whereas reversible hepatic injuries were more likely to be seen in elderly patients. As suggested in this paper, the development of carbamazepine hepatotoxicity is rare, and unpredictable with the present state of knowledge, but it is somehow related to disturbance of glutathione metabolism, although data in this regard are imperfect. There appear to be two types of carbamazepine-initiated idiosyncratic liver injury, hypersensitivity and toxin-induced. It is feasible that both are due to the accumulation of toxic metabolite(s), and arene oxides may probably be considered as damaging derivatives of carbamazepine metabolism. Despite the lack of clear-cut underlying clinical and experimental findings in those patients in whom an inherited weakness of drug eliminating capacity is present, those conditions that may deteriorate glutathione balance, may increase the possibility of the emergence of toxic events during carbamazepine therapy. Finally, some recommendations for carbamazepine therapy are presented.

Carbamazepine, hepatotoxicity, organic solvents, and paints

Hepatotoxicity secondary to carbamazepine is a serious condition which can be fatal. However, other concomitant medications or environmental factors may be the offending agents. In this case report, hepatotoxicity secondary to organic solvents and paints is described.

Carbamazepine-induced hepatitis in a patient with cervical myelopathy

Carbamazepine is a drug commonly used in the treatment of neuropathic pain. It is an iminostilbene derivative that is extensively metabolized by the liver. We describe a 66-year-old man with dysesthetic pain from cervical myelopathy who developed cholestatic hepatitis, skin rash, and eosinophilia after carbamazepine was administered for 5 weeks (total dose of 18.9gm). Withdrawal of carbamazepine led to complete resolution of both clinical and biochemical abnormalities within 3 weeks. Clinicians should be alert to this rare complication because it can be confused clinically with biliary tract sepsis and viral hepatitis.

Epidemiology of adverse reactions to carbamazepine as seen in a spontaneous reporting system

A survey was made of 505 reports on 713 adverse reactions to carbamazepine submitted to the Swedish Adverse Drug Reactions Advisory Committee from 1965-1987. For the period after 1972, the relation between the reports and sales statistics could be investigated. The total incidence of reported adverse reactions to carbamazepine was 4.5 per million defined daily doses (DDD), corresponding to 2.7 per million prescribed daily doses (PDD). Most often reported were skin reactions (48%), but reports on haematological (12%) and hepatic disorders (10%) were also frequent. Virtually all hepatic disorders and severe skin reactions, as well as the majority (60%) of the haematological reactions, occurred within the first 2 months of treatment. In view of the very low incidence of reported serious blood dyscrasias, such as pancytopenia (0.04/million PDD) and agranulocytosis (0.06/million PDD), continuous haematological monitoring seems to be of little value. The elderly appear to be at increased risk of developing blood dyscrasias and liver reactions, and alcohol abusers seem to represent a high-risk group for developing serious skin reactions.

Fatal hepatic necrosis associated with multiple anticonvulsant therapy

We report six fatal cases of hepatic necrosis in children associated with multiple anticonvulsant therapy. There was insufficient evidence to incriminate any single drug or combination of drugs, but it is noteworthy that sodium valproate was involved in only one case. We consider that an idiosyncratic metabolic reaction to the anticonvulsants was most likely. In five of the six cases hepatic failure was immediately preceded by a prolonged fit and we speculate that metabolic change from excessive neuronal activity may unmask the hepatotoxicity of anticonvulsants.

Drug-induced and toxic granulomatous hepatitis

The ability to induce granulomatous hepatitis has been attributed to numerous drugs; some sixty causative drugs have been culled from the literature for this review. Additionally, granulomas or granulomatoid lesions have resulted from occupational exposure to toxic substances (e.g. silica, copper sulphate, beryllium compounds), and particulate material from various therapeutic or diagnostic procedures (e.g. reactions to starch, talc, suture material, polyvinyl pyrrolidone, silicone, barium sulphate, thorium dioxide) or from intravenous drug abuse (e.g. talc). Clinically, patients with drug-induced or toxic granulomatous hepatitis may be asymptomatic. More frequently, the presentation is that of an acute febrile illness, with or without a rash and eosinophilia, followed by jaundice and biochemical evidence of hepatic dysfunction. The diagnosis of drug-induced granulomatous hepatitis is based largely on ruling out other aetiologies. Liver biopsy plays a key role in diagnosis. Recovery is the rule following withdrawal of the drug. Morphologically, drug-induced granulomas may be impossible to distinguish from those due to other causes. Associated lesions suggesting a drug aetiology include significant tissue eosinophilia, unicellular hepatocytic degeneration and necrosis, cholestasis and acute cholangitis or vasculitis. Special stains, polarizing and phase contrast microscopy, transmission and scanning electron microscopy and energy dispersive X-ray microanalysis all play a role in the aetiologic diagnosis of some types of granulomas.

Carbamazepine-induced acute cholangitis

We report the case of a patient with carbamazepine-induced cholestasis in whom histologic examination showed acute cholangitis. This type of lesion broadens the spectrum of carbamazepine-induced liver injury which also includes granuloma and hepatocellular necrosis. Its association with marked hypereosinophilia suggests that carbamazepine may cause acute cholangitis through an immunoallergic mechanism.

Acute hepatotoxicity after excessively high doses of carbamazepine on two occasions

A 2 1/2-year-old child being treated with carbamazepine (CBZ) for a seizure disorder on two separate occasions experienced elevated CBZ serum concentrations (28 and 23.2 mg/L), severe liver damage (SGOT greater than 6000 IU, SGPT greater than 5000 IU), and central nervous system manifestations (coma, lethargy, seizures). During the first episode, the time course of CBZ concentrations exhibited a nonlinear decline and was accompanied by CBZ-10,11-epoxide concentrations that were elevated 4-fold compared to normal values. Cerebrospinal fluid concentrations of CBZ and CBZ-10,11-epoxide were also elevated, although their ratios to serum concentrations did not suggest enhanced permeability of the central nervous system to these substances. The concentrations of CBZ-10,11-epoxide but not CBZ were elevated for the duration of time that the patient was comatose, suggesting that this metabolite may contribute to the neurotoxic side effects observed with CBZ therapy.

Alcohol withdrawal and carbamazepine

The use of pharmacologic intervention in the management of alcohol withdrawal syndrome is briefly presented. The use of carbamazepine, a tricyclic anticonvulsant with clinical efficacy in depressive illness, in alcohol withdrawal treatment is reviewed. A comparative analysis between carbamazepine and major drugs used in alcohol withdrawal syndrome is made. This includes the evaluation of both clinical advantages and disadvantages in addition to identification of drug adverse reaction and interaction with alcohol. The mechanism of action of carbamazepine is also examined. Carbamazepine appears to possess a useful pharmacotherapeutic potential in the management of acute alcohol withdrawal syndrome, and its use in long-term treatment is suggested.

Acute hepatitis in a patient treated with carbamazepine

A case of serious acute hepatic damage probably induced by carbamazepine (CBZ) is described. A 4-year-old patient with generalized tonic-clonic seizures was started on CBZ after various ineffective therapies. On the 10th day of CBZ therapy, he was readmitted to the hospital because of reappearance of fits, and went into hepatic coma. On the hypothesis that he was suffering an acute toxic reaction to CBZ, the drug was withdrawn (the serum level was not toxic) and the patient was subjected to peritoneal dialysis. The patient was discharged after 15 days in general conditions similar to those preceding the comatose state. The type of hepatic damage revealed by the laboratory tests and the early appearance of the clinical symptoms with non-toxic serum CBZ levels support the hypothesis of an idiosyncratic reaction to CBZ.

Side effects of carbamazepine, valproate and clonazepam during long-term treatment of epilepsy

Side effects of carbamazepine (CBZ), valproate (VPA) and clonazepam (CZP) are rare during long-term use but rather common and usually transient during the early phases of treatment. The usual side effects of CBZ are drowsiness, dizziness, and diplopia, which are dose dependent in long-term use, but CBZ does not seem to cause cognitive disturbances, as do phenobarbital and phenytoin. Other reactions to CBZ may include leukopenia, hyponatremia, disturbances of vitamin D metabolism and fortunately rarely, agranulocytosis and hepatitis. Use of VPA can lead to gastrointestinal discomfort, weight gain, hair loss, tremor and sedation, but these side effects are rather uncommon, mild, and transient during VPA monotherapy. Potentially hazardous reactions such as hepatitis and pancreatitis have occurred in a few patients on VPA, generally with multidrug therapy. Some of the side effects are dose related. They infrequently lead to withdrawal of VPA. Side effects limited to initiation of CZP therapy include drowsiness, ataxia, and behavioral changes; they are usually transient but can lead to dose reduction or even withdrawal of the drug. Except for development of tolerance, CZP seems to be practically free of long-term side effects.