Cyanamide hepatotoxicity. Incidence and clinico-pathological features

Adverse hepatic reactions associated with calcium carbimide and disulfiram therapy: Is there still a role for these drugs

Disulfiram and calcium carbimide are two alcohol deterrants widely used in alcoholism treatment, however, there exist great concerns over their safety. Reports on hepatotoxicity, mainly related to disulfiram therapy, have been published. The hepatotoxic potential of calcium carbimide is less well characterized. Here, we describe four cases of liver damage related to this therapeutic group that were submitted to a Registry of hepatotoxicity and point out the limitations that we face when prescribing these compounds. A reassessment of the role of these compounds in the management of alcohol dependence is clearly needed.

Comparison of cyanamide and placebo in the treatment of alcohol dependence of adolescents

AIMS

About 50% of alcoholic patients relapse within 3 months of treatment. Previous studies have suggested that cyanamide may help to prevent such relapse. The aim of our study was to assess the efficacy and safety of long-term cyanamide treatment in alcohol dependence of adolescents.

METHODS

In this, double-blind, placebo-controlled study, we recruited 26 patients, aged 16-19 years, with chronic (frequent and regular) or episodic (frequent, but irregular) alcohol dependence. Patients were randomly allocated treatment with cyanamide (200 mg daily) or a placebo for 90 days. Patients were assessed on the day the treatment was started, and on days 30 and 90, by interview, self-report, questionnaire and laboratory screening. Patients were classified as abstinent, relapsing or non-attending. Time to first treatment failure (relapse or non-attendance) was the primary outcome measure.

RESULTS

The cyanamide (n = 13) and placebo (n = 13) groups were well matched in terms of baseline demographic and alcohol-related variables. Mean cumulative abstinence duration was significantly greater in the cyanamide group than in the placebo group. Apart from occasional diarrhoea, there was no difference in side effects between groups.

CONCLUSIONS

Cyanamide seems to be an effective and well tolerated pharmacological adjunct to psychosocial and behavioural treatment programmes for the treatment of some adolescent alcohol-dependent patients. Because of reported hepatotoxic, haematological and dermatological side effects, patients should be observed continuously by experienced clinicians. Further studies are necessary to prove the efficacy of cyanamide in adolescents.

The role of acetaldehyde in the actions of alcohol (update 2000)

BACKGROUND

Recent advances in the field of acetaldehyde (AcH) research have raised the need for a comprehensive review on the role of AcH in the actions of alcohol. This update is an attempt to summarize the available AcH research.

METHODS

The descriptive part of this article covers not only recent research but also the development of the field. Special emphasis is placed on mechanistic analyses, new hypotheses, and conclusions.

RESULTS

Elevated AcH during alcohol intoxication causes alcohol sensitivity, which involves vasodilation associated with increased skin temperature, subjective feelings of hotness and facial flushing, increased heart and respiration rate, lowered blood pressure, sensation of dry mouth or throat associated with bronchoconstriction and allergy reactions, nausea and headache, and also reinforcing reactions like euphoria. These effects seem to involve catecholamine, opiate peptide, prostaglandin, histamine, and/or kinin mechanisms. The contribution of AcH to the pathological consequences of chronic alcohol intake is well established for different forms of cancer in the digestive tract and the upper airways. AcH seems to play a role in the etiology of liver cirrhosis. AcH may have a role in other pathological developments, which include brain damage, cardiomyopathy, pancreatitis, and fetal alcohol syndrome. AcH creates both unpleasant aversive reactions that protect against excessive alcohol drinking and euphoric sensations that may reinforce alcohol drinking. The protective effect of AcH may be used in future treatments that involve gene therapy with or without liver transplantation.

CONCLUSIONS

AcH plays a role in most of the actions of alcohol. The individual variability in these AcH-mediated actions will depend on the genetic polymorphism, not only for the alcohol and AcH-metabolizing enzymes but also for the target sites for AcH actions. The subtle balance between aversive and reinforcing, protecting and promoting factors will determine the overall behavioral and pathological developments.

Use of a monoclonal antibody against Lafora bodies for the immunocytochemical study of ground-glass inclusions in hepatocytes due to cyanamide

AIMS

Ground-glass inclusions (GGIs) in hepatocytes are known to be associated with cyanamide treatment in patients with alcohol dependency. The purpose of this study was to assess the reactivity of a monoclonal antibody (MAb) raised against polyglucosan and to detect early events in GGI formation.

METHODS AND RESULTS

Formalin-fixed paraffin-embedded liver tissues from four patients treated with cyanamide were used. Sections were stained with haematoxylin and eosin and periodic acid-Schiff with and without diastase digestion, and were immunohistochemically stained with the MAb. For electron microscopic study, routinely processed liver tissue from one patient was examined with conventional and immunoelectron microscopy with use of the MAb. All specimens from the four cyanamide-treated patients contained GGIs in the cytoplasm of hepatocytes, and these GGIs reacted intensely with the MAb. Fully developed GGIs contained various organelles, whereas early ones consisted primarily of glycogen granules and dilated smooth endoplasmic reticulum. In immunoelectron microscopic preparations, gold particles were located within GGIs, and the immunolabelled organelles appeared to be glycogen granules.

CONCLUSIONS

This novel MAb is useful for the detection of GGIs caused by cyanamide. Our results support the idea that GGI formation may result from specific abnormalities in glucose metabolism.

The role of acetaldehyde in the actions of alcohol (update 2000)

BACKGROUND

Recent advances in the field of acetaldehyde (AcH) research have raised the need for a comprehensive review on the role of AcH in the actions of alcohol. This update is an attempt to summarize the available AcH research.

METHODS

The descriptive part of this article covers not only recent research but also the development of the field. Special emphasis is placed on mechanistic analyses, new hypotheses, and conclusions.

RESULTS

Elevated AcH during alcohol intoxication causes alcohol sensitivity, which involves vasodilation associated with increased skin temperature, subjective feelings of hotness and facial flushing, increased heart and respiration rate, lowered blood pressure, sensation of dry mouth or throat associated with bronchoconstriction and allergy reactions, nausea and headache, and also reinforcing reactions like euphoria. These effects seem to involve catecholamine, opiate peptide, prostaglandin, histamine, and/or kinin mechanisms. The contribution of AcH to the pathological consequences of chronic alcohol intake is well established for different forms of cancer in the digestive tract and the upper airways. AcH seems to play a role in the etiology of liver cirrhosis. AcH may have a role in other pathological developments, which include brain damage, cardiomyopathy, pancreatitis, and fetal alcohol syndrome. AcH creates both unpleasant aversive reactions that protect against excessive alcohol drinking and euphoric sensations that may reinforce alcohol drinking. The protective effect of AcH may be used in future treatments that involve gene therapy with or without liver transplantation.

CONCLUSIONS

AcH plays a role in most of the actions of alcohol. The individual variability in these AcH-mediated actions will depend on the genetic polymorphism, not only for the alcohol and AcH-metabolizing enzymes but also for the target sites for AcH actions. The subtle balance between aversive and reinforcing, protecting and promoting factors will determine the overall behavioral and pathological developments.

Cyanamide-associated alcoholic liver disease: a sequential histological evaluation

This is the first study that we are aware of that followed the histopathological progression of the liver disease that was caused by the combination of both chronic alcohol use and cyanamide, an antidipsotropic agent. Two sequential liver biopsy specimens were obtained on 29 alcoholics who relapsed with varying histories of cyanamide treatment. Cyanamide induced ground-glass inclusions (GGIs) in the hepatocytes. Two groups were identified, depending on whether GGIs proliferated or regressed, which was, in turn, found contingent on the duration of cyanamide treatment and the drug-free period. Group 1 included 14 cases in which GGIs either emerged only in the second biopsy specimen or else were increased in the second specimen as compared in the initial specimen. Group 2 composed of 15 cases in which GGIs were either not observed in either specimen or decreased in the second specimen as compared in the initial specimen. Acidophilic bodies were sequentially increased in five cases (36%) of group 1 and in none of group 2. The severity of portal inflammation worsened in 10 cases (71%) of group 1 but in 2 cases (13%) of group 2, although the changes in fibrotic process did not differ between two groups. These differences could not be explained on the basis of the daily ethanol consumption and the length of relapses of the two groups. Thus, when cyanamide-treated alcoholics relapsed, the combined effect of cyanamide and alcohol produced the development of acidophilic bodies and portal inflammation along with the emergence of GGIs.

Disulfiram-induced hepatitis. Report of four cases and review of the literature

Liver test abnormalities following disulfiram therapy are common. However, overt disulfiram-induced hepatitis is rare but has a high mortality rate, specially when the etiologic role of disulfiram is not suspected and treatment is not discontinued. We report four cases of disulfiram-induced acute hepatitis with different degrees of severity and review the cases reported in the literature. The clinical spectrum of disulfiram hepatotoxicity ranges from minor elevation of serum aminotransferases to fulminant hepatitis. Although some patients with disulfiram-induced hepatitis have manifestations of hypersensitivity, recent clinical and experimental data suggest that disulfiram hepatotoxicity is produced by the accumulation of toxic metabolites.

Ground-glass hepatocytes with Lafora body like inclusions--histochemical, immunohistochemical and electronmicroscopic characterization

We report two adult patients whose liver biopsy specimens revealed numerous ground-glass hepatocytes due to inclusions resembling Lafora bodies. The inclusions were large, intracytoplasmic, pale, eosinophilic and kidney-shaped and were periodic acid-Schiff positive and HBsAg negative. Immunoperoxidase studies showed that the inclusions were positive for cytokeratins and alpha 1-antitrypsin. In case 1, the inclusions were not membrane-bound and consisted of secondary lysosomes and degenerate organelles including rough and smooth endoplasmic reticulum. In case 2, electronmicroscopy showed the inclusions were not membrane-bound, but consisted of dense granules, fibrils and vacuoles, with appearances very similar to Lafora bodies. Neither patient had myoclonus or epilepsy. Electronmicroscopy is important in differentiating the type of Lafora body like inclusions found in liver biopsies.