Liver failure due to antithyroid drugs: report of a case and literature review

Clinical Characteristics and Outcomes of Patients With Antithyroid Drug-Related Liver Injury

Context

Antithyroid drugs (ATDs) are the cornerstone of hyperthyroidism management. Hepatotoxicity due to ATDs can range from mild transaminase elevation to liver transplantation requirement and mortality.

Objective

The primary objective of the systematic review was to assess the clinical characteristics and outcomes of patients with drug induced liver injury (DILI) due to ATDs.

Methods

We conducted a systematic review of PUBMED, SCOPUS, and EMBASE on characteristics and outcomes of adults (>18 years) with DILI due to ATDs. We defined DILI as bilirubin ≥2.5 mg/dL or international normalized ratio >1.5 with any rise in alanine aminotransferase (ALT), aminotransferase (AST), or alkaline phosphatase (ALP), or an elevation of ALT or AST >5 times or ALP >2 times the upper limit of normal without jaundice/coagulopathy.

Results

The review included 100 articles describing 271 patients; 148 (70.8%) were female (N = 209). Mean age was 42.9 ± 17.2 years. Graves' disease was the most common indication for ATDs. Carbimazole/methimazole (CBM/MMI) was the most common offending agent (55.7%). DILI pattern was hepatocellular in 41.8%, cholestatic in 41.3%, and mixed in 16.9%. Outcomes included death in 11.8%, liver transplantation in 6.4%, partial improvement in 2.2%, and complete resolution in 79.6% with a median time (IQR) to resolution of 45 (20-90) days. Patients in the propylthiouracil (PTU) group had higher initial bilirubin, initial AST, initial ALT, peak ALT, peak AST, severe and fatal DILI, liver transplantation, and mortality than CBM/MMI. Rechallenge of antithyroid medication was infrequently reported (n = 16) but was successful in 75%.

Conclusion

DILI due to ATDs can present with different patterns and should prompt immediate drug discontinuation. Referral to a hepatologist should be considered if severe as transplantation is sometimes required. PTU-induced DILI may have worse outcomes than CBM/MMI.

Liver injury associated with drug intake during pregnancy

Drug use during pregnancy is not common. Drug-induced liver injury (DILI) is a potential complication that is rare but can adversely affect both the mother and the fetus. Although many drugs can directly cause hepatotoxicity, idiosyncratic liver injury is common in pregnancy. Underreporting of adverse drug reactions, lack of adequate literature regarding drug safety in pregnancy, and the inherent difficulty in diagnosing DILI during pregnancy make the management of this condition challenging. This review attempts to describe the existing literature regarding DILI in pregnancy, which is mainly in the form of case reports; several studies have looked at the safety of antithyroid drugs, antiretroviral drugs, and paracetamol, which have an indication for use in pregnancy; the relevant data from these studies with regard to DILI has been presented. In addition, the review describes the diagnosis of DILI, grading the disease severity, assessment of causality linking the drug to the adverse event, regulatory guidelines for evaluating the potential of drugs to cause liver injury, efforts to ensure better participation of women in clinical trials and studies in pregnant women population in particular, and the challenges involved in generating adequate research evidence. The establishment of DILI registries in various countries is an encouraging development; however, there is a need for promoting active, spontaneous reporting of adverse events during pregnancy to ensure rapid generation of evidence regarding the safety of a drug in pregnant women.

Macular Rash, Thrombocytopenia, and Hyperbilirubinemia in a Preterm Infant

Neonatal hyperthyroidism is usually caused by the passage of maternal thyroid receptor antibodies. This relatively rare condition has various manifestations including cholestasis, prematurity, and cardiomegaly. We present a case of a preterm infant with neonatal Graves' disease who presented with cholestasis, cardiomegaly, and a macularpapular rash that was thought to be suspicious for congenital infection. This case has been reported to illustrate lessons learnt for early identification of a neonate with Graves' disease in order to expedite treatment.

Therapeutic plasma exchange and continuous renal replacement therapy for severe hyperthyroidism and multi-organ failure: A case report

BACKGROUND

Severe hyperthyroidism is a life-threatening exacerbation of thyrotoxicosis, characterized by high fever and multiorgan failure. The most common medical treatments are administration of antithyroid drugs and radioactive iodine, and thyroidectomy. In some patients, antithyroid therapy is limited due to serious adverse effects or failure to control disease progression. In some extreme cases, such as thyroid storm, conventional therapy alone does not yield effective and rapid improvement before the development of multiorgan failure.

CASE SUMMARY

This report describes a Chinese patient with severe hyperthyroidism accompanied by multiorgan failure, who was transferred to the medical intensive care unit of our hospital. The patient presented with palpitations, vomiting, diarrhea, and shortness of breath for a week. Laboratory tests showed elevation of thyroid hormones. Hepatic failure occurred with high aminotransferase levels and jaundice. Given her abnormal liver function and medication history, we could not exclude diagnosis of propylthiouracil-induced hepatic failure. Moreover, she also suffered from heart failure. Therapeutic plasma exchange (commonly known as TPE) and continuous renal replacement therapy (commonly known as CRRT) were used as life-saving therapy, which resulted in notable improvement of clinical symptoms and laboratory tests.

CONCLUSION

Combined TPE and CRRT are safe and effective for patients with hyperthyroidism and multiorgan failure.

Propylthiouracil-induced liver failure and artificial liver support systems: a case report and review of the literature

BACKGROUND

Antithyroid drugs carry a potential risk of hepatotoxicity. Propylthiouracil (PTU) is commonly prescribed for patients with hyperthyroidism. PTU, however, can induce liver injury, ranging from mild asymptomatic elevation of aminotransferases to acute liver failure (ALF).

CASE PRESENTATION

This case reports on a 16-year-old Chinese girl with hyperthyroidism, who was admitted to our hospital for jaundice, nausea, and fatigue associated with severe hyperbilirubinemia and coagulopathy. She had been prescribed PTU 5 months earlier. There was no history of hypersensitivity to drugs, viral liver diseases, blood transfusion, or surgery. On the basis of her symptoms and the clinical data, she was diagnosed with PTU-induced ALF. Due to the limited number of available donor organs for liver transplantation, she was started on treatment with artificial liver support system (ALSS). After four sessions of ALSS, her clinical signs and symptoms were found to be markedly improved, and she was discharged 25 days after admission. Four months later, her liver function normalized.

CONCLUSION

Although PTU-induced liver failure is rare in clinical practice, liver function should be appropriately monitored during treatment with PTU. PTU-induced ALF in this patient was successfully managed with an ALSS, suggesting that the latter may be an alternative to liver transplantation.

Propylthiouracil-related Toxic Hepatitis: Impact of Silent Cases

Liver is the main organ which can metabolize many drugs or chemical agents. Toxic events developed by drugs are one of the most common causes of liver damage. Toxic hepatitis can be encountered in different clinical situations, such as acute hepatitis, fulminant hepatitis chronic hepatitis or cirrhosis. We aimed to report a case of asymptomatic toxic hepatitis in a patient taking propylthiouracil (PTU). A 38 years old female patient admitted to hospital complained of fatigue. She had no special medical history except Graves' disease. She had been taking PTU 300 mg/day for 1 month. She had no history of another medication, eating mushroom, alcohol consumption, traveling, family history of liver disease. Her physical examination was normal. Laboratory analysis revealed that alanine aminotransferase-543 U/L, aspartate aminotransferase-227 U/L, gamma glutamyl transferase-66 U/L and alkaline phosphatase-136 U/L. Serum levels of bilirubin and albumin, INR, complete blood count and thyroid function tests were all normal. She had normal liver function test (LFT) before using PTU. Propylthiouracil was discontinued and she was given methimazole. She was examined for the etiology of abnormal LFT, but no specific etiology could be recorded. She was thought to have toxic hepatitis related to PTU. In her follow-up LFT has turned to normal level (Table 1).

How to cite this article

Eser M, Basyigit S, Eser M, Nazligul Y. Propylthiouracil-related Toxic Hepatitis: Impact of Silent Cases. Euroasian J Hepato-Gastroenterol 2015;5(2):134-135.

Factors predicting abnormal liver function tests induced by Graves' disease alone: a retrospective cohort study

Abnormal liver function tests (LFTs) are often observed in patients with Graves' disease (GD). To date, there are limited data demonstrating the factors or biochemical indexes contributing to LFT abnormalities in this patient population. The aim of this study was to explore factors predicting abnormal LFTs induced by GD alone. This was a retrospective study of 289 consecutive cases of newly diagnosed and untreated patients with GD. All patients were divided into abnormal LFTs (group A) and normal LFTs (group B). In total, 205 (70.9%) cases were found to have at least 1 LFT abnormality. Among them, the frequencies of ALT, AST, ALP, γ-GTP, TBIL and DBIL abnormalities were 52.7%, 32.2%, 45.9%, 38.5%, 23.4%, 2.9%, respectively, and the number of patients with 1 to 6 hepatic variable abnormalities were 89, 64, 30, 16, 6 and 0, respectively. Logistic regression analysis was used to determine predictive factors contributing to abnormal LFTs. A receiver operating characteristic (ROC) curve was also plotted to verify the accuracy of predictors. In the univariate analysis, patients in group A had significantly higher FT3 concentration (37.5 vs 33.4 pmol/L, P = 0.009), FT4 concentration (85.7 vs 77.4 pmol/L, P = 0.002) and TRAb level (22.2 vs 17.4 IU/L, P < 0.001) when compared with those in group B. Binary logistic regression analysis identified higher FT4 concentration (odds ratio [OR]: 1.017, 95% confidence interval [CI]: 1.005-1.030, P = 0.006) and higher TRAb value (OR: 1.038, 95% CI:1.013-1.064, P = 0.003) to be independent risk factors predicting abnormal LFTs. The optimal cutoffs for FT4 and TRAb to predict abnormal LFTs were 75 pmol/L and 15 IU/L, respectively, based on ROC analysis.

Plasmaférese pré-tireoidectomia em paciente com tireotoxicose e hepatotoxicidade por propiltiouracil: relato de caso

A tireotoxicose é uma rara síndrome clínica decorrente da exacerbação do hipertireoidismo, de etiologia e fatores desencadeantes diversos. A abordagem terapêutica pode ser realizada por meio de medicamentos para bloqueio da síntese, secreção e/ou inibição da ação periférica hormonal, além de terapia dirigida aos fatores desencadeantes. Entretanto, em casos refratários, a plasmaférese surge como importante opção de tratamento. Relatamos o caso de um paciente com doença de Graves, internado com quadro de hepatotoxicidade grave por propiltiouracil, que evoluiu com tireotoxicose, sendo indicada plasmaférese para rápida redução dos hormônios tireoidianos, em preparo para a tireoidectomia total.

Acute liver failure associated with propylthiouracil in a pregnant 26-year-old woman

It seems appropriate to use propylthiouracil to treat maternal hyperthyroidism during the first trimester of pregnancy. We present the case of a 26-year-old woman with acute liver failure associated with propylthiouracil during the first trimester of pregnancy. She was successfully treated without liver transplantation. Attention should be paid to the possible occurrence of propylthiouracil-induced hepatotoxicity even during the first trimester of pregnancy.

Cytoprotective Effects of Organosulfur Compounds against Methimazole Induced Toxicity in Isolated Rat Hepatocytes

PURPOSE

Methimazole is a drug widely used in hyperthyroidism. However, life threatening hepatotoxicity has been associated with its clinical use. No protective agent has been found to be effective against methimazole induced hepatotoxicity yet. Hence, the capacity of organosulfur compounds to protect rat hepatocytes against cytotoxic effects of methimazole and its proposed toxic metabolite, N-methylthiourea was evaluated.

METHODS

Hepatocytes were prepared by the method of collagenase enzyme perfusion via portal vein. Cells were treated with different concentrations of methimazole, N methylthiourea, and organosulfur chemicals. Cell death, protein carbonylation, reactive oxygen species formation, lipid peroxidation, and mitochondrial depolarization were assessed as toxicity markers and the role of organosulfurs administration on them was investigated.

RESULTS

Methimazole caused a decrease in cellular glutathione content, mitochondrial membrane potential (ΔΨm) collapse, and protein carbonylation. In addition, an increase in reactive oxygen species (ROS) formation and lipid peroxidation was observed. Treating hepatocytes with N methylthiourea caused a reduction in hepatocytes glutathione reservoirs and an elevation in carbonylated proteins, but no significant ROS formation, lipid peroxidation, or mitochondrial depolarization was observed. N-acetyl cysteine, allylmercaptan, and diallyldisulfide attenuated cell death and prevented ROS formation and lipid peroxidation caused by methimazole. Furthermore, organosulfur compounds diminished methimazole induced mitochondrial damage and reduced the carbonylated proteins. In addition, these chemicals showed protective effects against cell death and protein carbonylation induced by methimazole metabolite.

CONCLUSION

Organosulfur chemicals extend their protective effects against methimazole-induced toxicity by attenuating oxidative stress caused by this drug and preventing the adverse effects of methimazole and/or its metabolite (s) on subcellular components such as mitochondria.

Ameliorative effects of taurine against methimazole-induced cytotoxicity in isolated rat hepatocytes

Methimazole is used as an antithyroid drug to control the symptoms of hyperthyroidism and maintain patients in a euthyroid state. Administration of this drug is associated with agranulocytosis and hepatotoxicity, which are the two most significant adverse effects. The present investigation was conducted to study the protective role of taurine against cytotoxicity induced by methimazole and its proposed reactive intermediary metabolite, N-methylthiourea, in an in vitro model of isolated rat hepatocytes.

At different points in time, markers such as cell viability, reactive oxygen species (ROS) formation, lipid peroxidation, mitochondrial membrane potential, and hepatocyte glutathione content were evaluated.

Treating hepatocytes with methimazole resulted in cytotoxicity characterized by the reduction in cell viability, an increase in ROS formation and lipid peroxidation, mitochondrial membrane potential collapse, and a reduction in cellular glutathione content. Furthermore, a significant amount of oxidized glutathione (GSSG) was formed when rat hepatocytes were treated with methimazole. N-methylthiourea toxicity was accompanied by a reduction in cellular GSH content, but no significant changes in lipid peroxidation, ROS formation, GSSG production, or changes in mitochondrial membrane potential were detected. Administration of taurine (200 μM) effectively reduced the toxic effects of methimazole or its metabolite in isolated rat hepatocytes.

Evolution of pediatric thyroid surgery at a tertiary medical center

BACKGROUND

Thyroidectomy in the pediatric population is often avoided due to perceived risks in children. With growing subspecialization and establishment of high volume endocrine surgery centers, the indications for thyroid surgery and extent of resection continue to change. We examined the evolution of pediatric thyroid surgery at a high volume tertiary medical center.

METHODS

From our prospectively collected database, we reviewed medical records of individuals younger than 19 y who underwent thyroidectomy at our institution from 1994 to 2009. Patients were divided into two groups: (1) before establishment of our endocrine surgery center (1994-2001) and (2) since establishment of the center (2002-2009).

RESULTS

We identified 78 operations performed on 74 patients with a median age of 15 (range 3-18) y. We found that the number of patients doubled in the later time period, with 26 operations in group 1 and 52 in group 2. The age of patients and percentage of females were similar between groups. After establishment of the endocrine surgery center, there was a significant increase in total thyroidectomies for all indications, including significantly more for benign disease. Overall, 9% of the patient population experienced transient complications, with no permanent complications or long-term sequelae.

CONCLUSIONS

Pediatric thyroid surgery is extremely safe, especially when performed at a high volume endocrine surgery center. We more often select surgical treatment for benign disease and choose total thyroidectomy over limited resection. This may reflect increasing confidence in the safety and efficacy of surgery and reliability of thyroid hormone replacement.

Toxicological considerations for antithyroid drugs in children

INTRODUCTION

Propylthiouracil (PTU), methimazole (MMI) and carbimazole are indicated for the treatment of hyperthyroidism in adult and pediatric patients. The aim of this review is to present all the relevant information regarding the use of antithyroid drugs (ATD) in pediatric thyrotoxic cases, the pediatric toxicology of ATD and the warning which has recently been issued for PTU by the FDA.

AREAS COVERED

Epidemiology, diagnosis and treatment of pediatric thyrotoxicosis are all presented in this article. The authors also extensively discuss the details regarding the pharmacology, bioactivation, biodisposition, bioavailability and pharmacokinetic properties of the two main ATD (MMI and PTU).

EXPERT OPINION

The FDA recently reported that use of PTU is associated with a higher risk for clinically serious or fatal liver injury compared to MMI in both adult and pediatric patients. They also found that congenital malformations were reported approximately three times more often with prenatal exposure to MMI compared with PTU and especially with the use of MMI during the first trimester of pregnancy. The authors believe that PTU should not be used in pediatric patients unless the patient is allergic to or intolerant of MMI, and there are no other treatment options available. That being said, PTU may be the treatment of choice during, and just before, the first trimester of pregnancy.