Management of amiodarone-related thyroid problems

In Vivo Evaluation of the Pharmacokinetic Interaction between Levothyroxine and Amiodarone in Rat Plasma: Evaluation of Importance of Therapeutic Drug Monitoring during Co-Therapy

Amiodarone-induced thyrotoxicosis (AIT) is a common condition in patients who are receiving amiodarone for cardiac arrhythmia. This risk is elevated in iodine-deficient regions. Levothyroxine is the standard treatment for patients with hypothyroidism. This investigation is concerned with the evaluation of the possible pharmacokinetic interaction between amiodarone and levothyroxine upon co-therapy in rats and to investigate the cause of thyrotoxicosis. A selective, sensitive and precise RP-HPLC method was developed for the simultaneous determination of levothyroxine and amiodarone in rat plasma. A stationary phase of C18 Xterra RP column and a mobile phase consisting of acetonitrile: acidified water with 0.1% trifluoracetic acid (pH = 4.8) with gradient elution were used. The experiment was conducted at ambient temperature with flow rate of 1.5 mL/min for the chromatographic separation and quantitation of the investigated drugs. Protein precipitation with methanol was applied for the analysis of the two drugs in rat plasma. The method was linear over concentration range of 5-200 μg/mL for both levothyroxine and amiodarone. The European Medicines Agency guideline was applied for the validation of the developed bioanalytical method. The method was successfully applied to in vivo pharmacokinetic study in which levothyroxine and amiodarone were quantified in plasma of rats after receiving an oral dose of levothyroxine and amiodarone. After the calculation of the pharmacokinetic parameters, a statistical analysis was performed to elucidate the existence of significant difference between test and control groups in rats. The combination of levothyroxine and amiodarone significantly decreased levothyroxine bioavailability in rats, making the therapeutic drug monitoring mandatory in patients receiving levothyroxine and amiodarone. In addition, the increased clearance of levothyroxine upon the co-administration with amiodarone may explain the reported hypothyroidism.

The roles of thyroidectomy in patients with amiodarone-induced thyrotoxicosis: A systematic review

The principal management of Amiodarone-induced-thyrotoxicosis (AIT) is balancing cardiac-thyroid conditions. However, the role of thyroidectomy is still contentious. This systematic review aims to provide insights into the roles of thyroidectomy in the management of AIT. This systematic review encompasses 303 AIT patients who underwent thyroidectomy from 14 studies. The indication of thyroidectomy can be due to cardiac factors, thyrotoxicosis conditions, and patient-physician considerations. Thyroidectomy is more effective in improving thyroid hormone status, cardiac function, and mortality compared to optimal medical therapy, especially in those with left ventricular ejection fraction < 40 %. Thyroidectomy is effective in improving cardiac function and mortality due to shorter duration for achieving euthyroid. Thyroidectomy and medical therapy have comparable side effects. However, the identification of high-risk patients may reduce thyroidectomy complications. Thus, thyroidectomy should not be viewed as the last resource and should be performed immediately when indicated.

Monitoring thyroid function during amiodarone use

Amiodarone is an antiarrhythmic drug used to treat cardiac tachyarrhythmias. It has many adverse effects, with thyroid dysfunction one of the most notable. Through various mechanisms, both thyrotoxicosis and hypothyroidism can occur secondary to amiodarone therapy. There are two types of amiodarone-induced thyrotoxicosis: type 1 occurs in those with pre-existing thyroid disease and is treated with thionamide, whereas type 2 occurs in those without and is treated with glucocorticoids. Patients with amiodarone-induced hypothyroidism may be given levothyroxine to replace thyroid hormone, but in some cases, the appropriate management may be cessation of amiodarone.

Development and Validation of a Prediction Model for Incident Hypothyroidism in a National Chronic Kidney Disease Cohort

CONTEXT

Hypothyroidism is a common yet under-recognized condition in patients with chronic kidney disease (CKD), which may lead to end-organ complications if left untreated.

OBJECTIVE

We developed a prediction tool to identify CKD patients at risk for incident hypothyroidism.

METHODS

Among 15 642 patients with stages 4 to 5 CKD without evidence of pre-existing thyroid disease, we developed and validated a risk prediction tool for the development of incident hypothyroidism (defined as thyrotropin [TSH] > 5.0 mIU/L) using the Optum Labs Data Warehouse, which contains de-identified administrative claims, including medical and pharmacy claims and enrollment records for commercial and Medicare Advantage enrollees as well as electronic health record data. Patients were divided into a two-thirds development set and a one-third validation set. Prediction models were developed using Cox models to estimate probability of incident hypothyroidism.

RESULTS

There were 1650 (11%) cases of incident hypothyroidism during a median follow-up of 3.4 years. Characteristics associated with hypothyroidism included older age, White race, higher body mass index, low serum albumin, higher baseline TSH, hypertension, congestive heart failure, exposure to iodinated contrast via angiogram or computed tomography scan, and amiodarone use. Model discrimination was good with similar C-statistics in the development and validation datasets: 0.77 (95% CI 0.75-0.78) and 0.76 (95% CI 0.74-0.78), respectively. Model goodness-of-fit tests showed adequate fit in the overall cohort (P = .47) as well as in a subcohort of patients with stage 5 CKD (P = .33).

CONCLUSION

In a national cohort of CKD patients, we developed a clinical prediction tool identifying those at risk for incident hypothyroidism to inform prioritized screening, monitoring, and treatment in this population.

The role of amiodarone in post-operative hypothyroidism patient with factitious thyrotoxicosis and atrial fibrillation: A case report

INTRODUCTION

Factitious thyrotoxicosis includes all causes of thyrotoxicosis from the short or long-term ingestion of thyroid hormone, of which one of the complications is atrial fibrillation.

CASE PRESENTATION

A woman, 71 years old, complained of chest palpitations. She had a medical history of thyroidectomy, hypertension, and dyslipidemia. In addition, she took Levothyroxine, amlodipine and simvastatin regularly. On physical examination, the general status was weak, with vital signs showing blood pressure (BP) of 170/100 mmHg, heart rate (HR) of 130-150 bpm, irregular rhythm, respiratory rate (RR) of 20×/min, axillary temperature of 36.8 °C, and oxygen saturation (SpO2) 98 % with room air. The abnormal laboratory found were significant increase in total T4, total T3, FT4, and low levels of TSH. The first electrocardiogram (ECG) showed AF and Burch Watorfsky's score was 45. The AF was treated with a loading dose of amiodarone 150 mg in 10 min and decreased gradually. She had received a high-calorie, protein and low-salt diet of 2100 kcal/day, termination Levothyroxine usage, propranolol of 10 mg/8 h, amlodipine of 5 mg/day, and lisinopril of 5 mg/day. Treatment for AF was continued with a maintenance dose of amiodarone IV 300 mg in 6 h, then 600 mg in 18 h, warfarin tablet 2 mg/day (according to treatment from a cardiologist), and atorvastatin 20 mg/day at night. After 6 days of treatment, the patient experienced improvement and continued discharge. The patient improved on an outpatient basis and was monitored periodically.

DISCUSSION

Monitored treatment of thyrotoxicosis and AF management with 3 principles can minimize complication severity.

CONCLUSION

Early, effective and monitored treatment of thyrotoxicosis is vital to manage AF in achieving a better outcome.

High Comorbidity in Premature Infant: Abdominal Aortic Thrombosis, Wolff-Parkinson-White Syndrome, Secondary Hypothyroidism

Background. Neonatal thromboses, both venous and arterial, are a rare pathology, and experience in systemic thrombolysis is very low. Thus, the methods of adult management are currently being adapted to pediatric practice.

Clinical case description. This report describes clinical case of abdominal aortic thrombosis in a premature infant with later diagnosed Wolff-ParkinsonWhite syndrome and acquired hypothyroidism developed due to antiarrhythmic therapy.

Conclusion. The premature boy had high comorbidity that required many specialists’ involvement. Timely systemic thrombolytic therapy and antiarrhythmic drugs selection made it possible to save the child's life and most likely to avoid disability in the future. 

Total thyroidectomy in a patient awaiting heart transplant with amiodarone-induced thyrotoxicosis: A case report

Thyroid function may have a severe impact in cardiac function. Herein, we present the case report of a 53-year-old male patient awaiting heart transplant with amiodarone induced thyrotoxicosis that presented a marked improvement of his cardiac function after total thyroidectomy.

Incidence of hyperthyroidism in patients with bipolar or schizoaffective disorder with or without lithium: 21-year follow-up from the LiSIE retrospective cohort study

BACKGROUND

Lithium-associated hyperthyroidism is much rarer than lithium-associated hypothyroidism. Yet, it may be of substantial clinical significance for affected individuals. For instance, lithium-associated hyperthyroidism could destabilise mood, mimic manic episodes and impact physical health. Only few studies have explored incidence rates of lithium-associated hyperthyroidism. Even fewer studies have compared incidence rates according to lithium exposure history.

OBJECTIVES

To determine the impact of lithium treatment on the incidence rate of hyperthyroidism in patients with bipolar or schizoaffective disorder and assess its aetiology.

DESIGN

This study is part of the LiSIE (Lithium - Study into Effects and Side Effects) retrospective cohort study.

METHODS

Between 1997 and 2017, patients in the Swedish region of Norrbotten with a diagnosis of bipolar or schizoaffective disorder were screened for all episodes of overt hyperthyroidism in form of thyrotoxicosis or thyroiditis. Incidence rates of episodes of hyperthyroidism per 1000 person-years (PY) were compared in relation to lithium exposure; concurrent, previous, or no exposure ever (lithium-naïve patients).

RESULTS

In 1562 patients, we identified 16 episodes of hyperthyroidism corresponding to an incidence rate of 0.88 episodes per 1000 PY. Ninety-four percent of episodes had occurred in women. Patients who had concurrently been exposed to lithium, had an incidence rate of 1.35 episodes per 1000 PY. Patients who had previously been exposed to lithium had an incidence rate of 0.79 per 1000 PY. Patients who had never been exposed to lithium had an incidence rate of 0.47 per 1000 PY. There were no significant differences in the risk ratios for patients with concurrent or previous exposure compared with lithium-naïve patients, neither for hyperthyroidism overall, thyrotoxicosis, or thyroiditis.

CONCLUSION

Lithium-associated hyperthyroidism seems uncommon. The risk of hyperthyroidism does not seem significantly higher in patients with current or previous lithium exposure than in lithium-naïve patients.

Antiviral activity of amiodarone in SARS-CoV-2 disease

Amiodarone seems to exhibit some antiviral activity in the disease caused by SARS-CoV-2. Here we have examined the SARS-CoV-2 disease course in the entire population of the Czech Republic and compared it with the course of the disease in patients treated with amiodarone in two major Prague’s hospitals. In the whole population of the Czech Republic SARS-CoV-2 infected 1665070 persons (15.6 %) out of 10694000 (100 %) between 1 April 2020 and 30 June 2021. In the same time period only 35 patients (3.4 %) treated with amiodarone were infected with SARS-CoV-2 virus out of 1032 patients (100 %) who received amiodarone. It appears that amiodarone can prevent SARS-CoV-2 virus infection by multiple mechanisms. In in-vitro experiments it exhibits SARS-CoV-2 virus replication inhibitions. Due to its anti-inflammatory and antioxidant properties, it may have beneficial effect on the complications caused by SARS-CoV-2 as well. Additionally, inorganic iodine released from amiodarone can be converted to hypoiodite (IO-), which has antiviral and antibacterial activity, and thus can affect the life cycle of the virus.

Antiviral activity of amiodarone in SARS-CoV-2 disease

Amiodarone seems to exhibit some antiviral activity in the disease caused by SARS-CoV-2. Here we have examined the SARS-CoV-2 disease course in the entire population of the Czech Republic and compared it with the course of the disease in patients treated with amiodarone in two major Prague's hospitals. In the whole population of the Czech Republic SARS-CoV-2 infected 1665070 persons (15.6 %) out of 10694000 (100 %) between 1 April 2020 and 30 June 2021. In the same time period only 35 patients (3.4 %) treated with amiodarone were infected with SARS-CoV-2 virus out of 1032 patients (100 %) who received amiodarone. It appears that amiodarone can prevent SARS-CoV-2 virus infection by multiple mechanisms. In in-vitro experiments it exhibits SARS-CoV-2 virus replication inhibitions. Due to its anti-inflammatory and antioxidant properties, it may have beneficial effect on the complications caused by SARS-CoV-2 as well. Additionally, inorganic iodine released from amiodarone can be converted to hypoiodite (IO-), which has antiviral and antibacterial activity, and thus can affect the life cycle of the virus.

AMIODARONE AND THYROID DYSFUNCTION

Thyroid gland has a key role in maintaining the body homeostasis. Thyroxine is the main hormone secreted from the thyroid gland, its effect being predominantly achieved after the intracellular conversion of thyroxine to triiodothyronine, which exhibits a higher affinity for the receptor complex, thus modifying gene expression of the target cells. Amiodarone is one of the most commonly used antiarrhythmics in the treatment of a broad spectrum of arrhythmias, usually tachyarrhythmias. Amiodarone contains a large proportion of iodine, which is, in addition to the intrinsic effect of the medication, the basis of the impact on thyroid function. It is believed that 15%-20% of patients treated with amiodarone develop some form of thyroid dysfunction. Amiodarone may cause amiodarone-induced hypothyroidism (AIH) or amiodarone-induced thyrotoxicosis (AIT). AIT is usually developed in the areas with too low uptake of iodine, while AIH is developed in the areas where there is a sufficient iodine uptake. Type 1 AIT is more common among patients with an underlying thyroid pathology, such as nodular goiter or Graves' (Basedow's) disease, while type 2 mostly develops in a previously healthy thyroid. AIH is more common in patients with previously diagnosed Hashimoto's thyroiditis. Combined types of the diseases have also been described. Patients treated with amiodarone should be monitored regularly, including laboratory testing and clinical examinations, to early detect any deviations in the functioning of the thyroid gland. Supplementary levothyroxine therapy is the basis of AIH treatment. In such cases, amiodarone therapy quite often need not be discontinued. Type 1 AIT is treated with thyrostatic agents, like any other type of thyrotoxicosis. If possible, the underlying amiodarone therapy should be discontinued. In contrast to type 1 AIT, the basic pathophysiological substrate of which is the increased synthesis and release of thyroid hormones, the basis of type 2 AIT is destructive thyroiditis caused by amiodarone, desethylamiodarone as its main metabolite, and an increased iodine uptake. Glucocorticoid therapy is the basis of treatment for this type of disease.

Evaluating pharmacists' knowledge, attitude, and practices toward amiodarone cross-reactivity with iodine: a cross-sectional pilot study

Introduction

Iodine is a vital mineral of the human body that acts by maintaining the health of the thyroid gland. Research has shown that iodine-rich food allergy (i.e., seafood allergy) is not caused by iodine itself; instead, it is caused by other proteins including tropomyosin and parvalbumin in shellfish and fish, respectively. Amiodarone is a commonly used antiarrhythmic agent containing a significant amount of iodine.

Objective

This study's objective was to assess pharmacists' knowledge, attitude, and practices toward the misconception of iodine allergy and the cross-reactivity with amiodarone.

Methods

In February 2020, a cross-sectional study was conducted by sending out an online survey to three pharmaceutical organizations (Saudi Pharmaceutical Society, Kuwait Pharmaceutical Association, and Oman Pharmaceutical Society). Additionally, an electronic questionnaire was administered to pharmacists attending the Dubai International Pharmaceuticals and Technologies Conference and Exhibition 2020 (DUPHAT). Chi-square or Fisher's exact test, when appropriate, were used to compare categorical variables. The statistical analyses were carried out using SPSS software.

Results

Data were collected from 66 respondents. However, only 61 (92.4%) were included in the final analysis following the exclusion of incomplete responses. The mean age of participants was 35 ± 8.48 years. The majority of participants did not have the Board of Pharmacy Specialties Certification (54.1%). Moreover, (41%) of participants licensed as pharmacists with more than 10 years of initial pharmacy licensure. Forty-three (70.5%) of participants had the misconception that iodine allergy should be considered before amiodarone administration, 20/32 (62.5%) of whom considered iodine allergy alone thought that premedication with corticosteroids and/or antihistamines is necessary. Concerning iodine allergy and amiodarone use, there was no significant difference in knowledge between the pharmacists who have board certification and those who did not.

Conclusion

Pharmacists' misconception concerning iodine allergy and cross-reactivity with amiodarone was evident. Implementation of educational programs targeting pharmacists is necessary to correct these misconceptions.

Thyroid Dysfunction under Amiodarone in Patients with and without Congenital Heart Disease: Results of a Nationwide Analysis

Background: Amiodarone has a profound adverse toxicity profile. Large population-based analyses quantifying the risk of thyroid dysfunction (TD) in adults with and without congenital heart disease (ACHD) are lacking. Methods: All adults registered with a major German health insurer (≈9.2 million members) with amiodarone prescriptions were analyzed. Occurrence of amiodarone-associated TD was assessed. Results: Overall, 48,891 non-ACHD (37% female; median 73 years) and 886 ACHD (34% female; median 66 years) received amiodarone. Over 184,787 patient-years, 10,875 cases of TD occurred. The 10-year risk for TD was 38% in non-ACHD (35% ACHD). Within ACHD, compared to amiodarone-naïve patients, the hazard ratio (HR) for TD was 3.9 at 4 years after any amiodarone exposure. TD was associated with female gender (HR 1.42, p < 0.001) and younger age (HR 0.97 per 10 years, p = 0.009). Patients with congenital heart disease were not at increased risk (HR 0.98, p = 0.80). Diagnosis of complex congenital heart disease, however, was a predictor for TD (HR 1.56, p = 0.02). Amiodarone was continued in 47% of non-ACHD (38% ACHD), and 2.3% of non-ACHD (3.5% ACHD) underwent thyroid surgery/radiotherapy. Conclusions: Amiodarone-associated TD is common and comparable in non-ACHD and ACHD. While female gender and younger age are predictors for TD, congenital heart disease is not necessarily associated with an elevated risk.

Detailed Molecular Mechanisms Involved in Drug-Induced Non-Alcoholic Fatty Liver Disease and Non-Alcoholic Steatohepatitis: An Update

Non-alcoholic fatty liver disease (NAFLD) and non-alcoholic steatohepatitis (NASH) are some of the biggest public health challenges due to their spread and increasing incidence around the world. NAFLD is characterized by intrahepatic lipid deposition, accompanied by dyslipidemia, hypertension, and insulin resistance, leading to more serious complications. Among the various causes, drug administration for the treatment of numerous kinds of diseases, such as antiarrhythmic and antihypertensive drugs, promotes the onset and progression of steatosis, causing drug-induced hepatic steatosis (DIHS). Here, we reviewed in detail the major classes of drugs that cause DIHS and the specific molecular mechanisms involved in these processes. Eight classes of drugs, among the most used for the treatment of common pathologies, were considered. The most diffused mechanism whereby drugs can induce NAFLD/NASH is interfering with mitochondrial activity, inhibiting fatty acid oxidation, but other pathways involved in lipid homeostasis are also affected. PubMed research was performed to obtain significant papers published up to November 2021. The key words included the class of drugs, or the specific compound, combined with steatosis, nonalcoholic steatohepatitis, fibrosis, fatty liver and hepatic lipid deposition. Additional information was found in the citations listed in other papers, when they were not displayed in the original search.

Prevalence and factors associated with chronic use of levothyroxine: A cohort study

Importance

Levothyroxine prescriptions are rising worldwide. However, there are few data on factors associated with chronic use.

Objective

To assess the prevalence of chronic levothyroxine use, its rank among other chronic drugs and factors associated with chronic use. To assess the proportion of users outside the therapeutic range of thyroid-stimulating hormone (TSH).

Design

Cohort study (CoLaus|PsyCoLaus) with recruitment from 2003 to 2006. Follow-ups occurred 5 and 10 years after baseline.

Participants

A random sample of Lausanne (Switzerland) inhabitants aged 35–75 years.

Main outcomes

We evaluated the prevalence of chronic levothyroxine use and we then ranked it among the other most used chronic drugs. The ranking was compared to data from health insurance across the country. We assessed the association between each factor and chronic levothyroxine use in multivariable logistic regression models. The proportion of chronic levothyroxine users outside the usual TSH therapeutic range was assessed.

Results

4,334 participants were included in the analysis (mean±SD age 62.8±10.4 years, 54.9% women). 166 (3.8%) participants were chronic levothyroxine users. Levothyroxine was the second most prescribed chronic drug after aspirin in the cohort (8.2%) and the third most prescribed when using Swiss-wide insurance data. In multivariable analysis, chronic levothyroxine use was associated with increasing age [odds ratio 1.03, 95% confidence interval 1.01–1.05 per 1-year increase]; female sex [11.87 (5.24–26.89)]; BMI [1.06 (1.02–1.09) per 1-kg/m2 increase]; number of concomitant drugs [1.22 (1.16–1.29) per 1-drug increase]; and family history of thyroid pathologies [2.18 (1.37–3.48)]. Among chronic levothyroxine users with thyroid hormones assessment (n = 157), 42 (27%) were outside the TSH therapeutic range (17% overtreated and 10% undertreated).

Conclusions

In this population-based study, levothyroxine ranked second among chronic drugs. Age, female sex, BMI, number of drugs and family history of thyroid pathologies were associated with chronic levothyroxine use. More than one in four chronic users were over- or undertreated.

Patterns of Thyroid Hormone Prescription in Patients with Bipolar or Schizoaffective Disorder: Findings from the LiSIE Retrospective Cohort Study

The prescription of thyroid hormone replacement therapy (THRT) has increased in the general population; the thyroid stimulating hormone (TSH) threshold to initiate THRT has decreased. It remains unclear whether a similar trend has occurred in patients with bipolar disorder (BD). In this work we explore patterns and trends of prescribing THRT in patients with BD or schizoaffective disorder (SZD) with an observational study and time-trend analysis in the framework of the LiSIE (Lithium-Study into Effects and Side Effects) retrospective cohort study. In most patients, THRT was initiated for subclinical hypothyroidism. The median TSH at which THRT was started was 6.0 (IQR 4.0) mIU/L and the median free serum thyroxine (fT4) at which THRT was started was 11.8 (IQR 3.9) pmol/L. The median TSH concentration at the start of THRT decreased annually with 0.10 mIU/L (p = 0.047) and was higher in patients treated with lithium than in patients treated with other mood stabilisers (p = 0.02). In conclusion, THRT was typically initiated in the context of mild or absent alterations of thyroid function tests with a decreasing TSH threshold. As THRT is rarely reversed once initiated, clinicians need to weigh up potential benefits and risks when prescribing THRT for subclinical hypothyroidism in patients with BD or SZD.

Delayed diagnosis of dilated thyrotoxic cardiomyopathy with coexistent multifocal atrial tachycardia: a case report

Background

Thyroid storm (TS) is a rare but potentially life-threatening sequelae of untreated or undertreated hyperthyroidism. While TS frequently causes high-output heart failure, low-output heart failure related to dilated cardiomyopathy (DCM) is extremely rare. Tachycardia is a common clinical presentation of TS, and β1-selective blockers are the first-line agents for treating TS-associated tachycardia. However, given that β-blockers have negative chronotropic and negative inotropic effects, amiodarone may be safe and effective for the treatment of TS-induced tachyarrhythmia in patients with moderate to severe heart failure. While long-term amiodarone administration causes hypothyroidism, or less frequently, hyperthyroidism, little is known about the effects of short-term amiodarone administration on thyroid function.

Case presentation

A 31-year-old healthy woman presented with worsening dyspnoea. She was tachycardic with multifocal atrial tachycardia (MAT) of 184 beats/min, confirmed by electrocardiogram. Echocardiographic findings were consistent with DCM, with an ejection fraction of 20%. Thus, she was initially diagnosed with acute heart failure due to DCM with coexistent MAT. Tachycardia persisted despite cardioversion attempts and treatment with multiple anti-arrhythmic drugs. Consequently, she rapidly progressed to cardiogenic shock and respiratory decompensation, which required intubation and an intra-aortic balloon pump support. Moreover, the undiagnosed Graves' disease, lack of suspicion, and postponed analysis of thyroid function tests led to a delayed diagnosis of TS. Amiodarone, which was initiated for MAT, unexpectedly ameliorated thyrotoxicosis, resulting in a euthyroid state and the patient’s significantly improved condition and cardiac function. She was discharged on day 40. Finally, she underwent total thyroidectomy; thyroid pathology was consisting with Graves' disease. Her postoperative course was uneventful.

Conclusions

Herein, we describe a case of delayed diagnosis of dilated thyrotoxic cardiomyopathy with coexistent MAT. The patient required intensive care due to the catastrophic sequelae and was successfully treated with amiodarone. This is the first case report of TS-associated MAT and highlights the clinical importance of high suspicion of TS in de novo heart failure with any tachyarrhythmia or DCM of unknown etiology and the potential effects of short-term amiodarone administration in the treatment of TS.

Amiodarone-induced type 2 thyrotoxicosis

The authors present a case of a 55-year-old gentleman with a medical history of atrial fibrillation on amiodarone who presented with weight loss, palpitations and exertional dyspnoea. Thyroid function tests revealed thyrotoxicosis with a free thyroxine (T4) of 117 pmol/L and a thyroid-stimulating hormone (TSH) of <0.008 mIU/L. Interleukin-6 level was low. The negative TSH-receptor antibody status, the presence of a small thyroid gland with heterogeneous echotexture and decreased internal vascularity on ultrasound together with the relatively quick drop in free T4 and free tri-iodothyronine (T3) levels once prednisolone therapy was added to carbimazole suggested that this was typical of amiodarone-induced thyrotoxicosis (AIT) type 2. Subsequently, carbimazole was discontinued and treatment with prednisolone was continued. This case highlights that AIT management may be challenging and it is of paramount importance to establish the type of AIT present as this will guide management and is key to improving prognosis.

A review of species differences in the control of, and response to, chemical-induced thyroid hormone perturbations leading to thyroid cancer

This review summarises the current state of knowledge regarding the physiology and control of production of thyroid hormones, the effects of chemicals in perturbing their synthesis and release that result in thyroid cancer. It does not consider the potential neurodevelopmental consequences of low thyroid hormones. There are a number of known molecular initiating events (MIEs) that affect thyroid hormone synthesis in mammals and many chemicals are able to activate multiple MIEs simultaneously. AOP analysis of chemical-induced thyroid cancer in rodents has defined the key events that predispose to the development of rodent cancer and many of these will operate in humans under appropriate conditions, if they were exposed to high enough concentrations of the affecting chemicals. There are conditions however that, at the very least, would indicate significant quantitative differences in the sensitivity of humans to these effects, with rodents being considerably more sensitive to thyroid effects by virtue of differences in the biology, transport and control of thyroid hormones in these species as opposed to humans where turnover is appreciably lower and where serum transport of T4/T3 is different to that operating in rodents. There is heated debate around claimed qualitative differences between the rodent and human thyroid physiology, and significant reservations, both scientific and regulatory, still exist in terms of the potential neurodevelopmental consequences of low thyroid hormone levels at critical windows of time. In contrast, the situation for the chemical induction of thyroid cancer, through effects on thyroid hormone production and release, is less ambiguous with both theoretical, and actual data, showing clear dose-related thresholds for the key events predisposing to chemically induced thyroid cancer in rodents. In addition, qualitative differences in transport, and quantitative differences in half life, catabolism and turnover of thyroid hormones, exist that would not operate under normal situations in humans.

Challenges in the Management of Atrial Fibrillation With Subclinical Hyperthyroidism

Subclinical thyroid disorders have a high prevalence among older individuals and women. Subclinical hypothyroidism is diagnosed by elevated serum levels of thyroid-stimulating hormone (TSH) with thyroxine levels within the reference range, and subclinical hyperthyroidism is diagnosed by low TSH in conjunction with thyroxine and triiodothyronine levels within reference ranges. Atrial fibrillation is the most commonly diagnosed cardiac arrhythmia and has been associated with an increased risk of mortality, heart failure, stroke, and depression. Mechanistic data from animal and human physiology studies as well as observational data in humans support an association of subclinical hyperthyroidism with atrial fibrillation. Guidelines recommend the measurement of TSH in the evaluation of new-onset atrial fibrillation. All patients with overt hyperthyroidism should be treated, and treatment of subclinical hyperthyroidism should be considered in patients older than 65 years with TSH < 0.4 mlU/L, or in younger patients with TSH < 0.1 mlU/L. Guidelines also recommend screening for AF in patients with known hyperthyroidism. Wearable devices that measure the heart electrical activity continuously may be a novel strategy to detect atrial fibrillation in patients at risk. In this review, we explore the interplay between thyroid hormones and atrial fibrillation, management controversies in subclinical hyperthyroidism, and potential strategies to improve the management of atrial fibrillation in patients with subclinical hyperthyroidism.

Evaluation and Treatment of Amiodarone-Induced Thyroid Disorders

Amiodarone is a class III antiarrhythmic drug containing 37% iodine by weight, with a structure similar to that of thyroid hormones. Deiodination of amiodarone releases large amounts of iodine that can impair thyroid function, causing either hypothyroidism or thyrotoxicosis in susceptible individuals reflecting ~20% of patients administered the drug. Not only the excess iodine, but also the amiodarone (or its metabolite, desethylamiodarone) itself may cause thyroid dysfunction by direct cytotoxicity on thyroid cells. We present an overview of the epidemiology and pathophysiology of amiodarone-induced thyroid disorders, with a focus on the various forms of clinical presentation and recommendations for personalized management of each form.

Amiodarone Induced Thyrotoxicosis and Treatment Complications in a Man With Cyanotic Congenital Heart Disease: A Case Report

Background and Case: Amiodarone induced thyrotoxicosis (AIT) is a potentially life-threatening condition that exists in two main subtypes – AIT Type 1 (AIT1) and AIT Type 2 (AIT2). AIT1 is a form of iodine-induced hyperthyroidism with increased thyroid hormone synthesis, while AIT2 is a form of destructive thyroiditis with increased release of pre-formed thyroid hormone. This case report describes a patient with cyanotic congenital heart disease, who developed AIT with severe biochemical thyrotoxicosis. Due to complications to corticosteroids and thionamides, second-line treatment with cholestyramine and lithium was given which eventually restored euthyroidism, averting the need for thyroidectomy and its associated risks. Due to the presence of both typical and unusual features, the final diagnosis of AIT2 could only be retrospectively elucidated after a prolonged clinical course.

Conclusion: Corticosteroids are well-recognized to be the first-line treatment for AIT2. This case illustrates a rare phenomenon: successful treatment of AIT2 with lithium and cholestyramine. In patients who develop complications from first-line therapy, prompt treatment with alternative agents may successfully avert thyroidectomy and its associated risks.

Inhibitory Effects of Dronedarone on Small Conductance Calcium Activated Potassium Channels in Patients with Chronic Atrial Fibrillation: Comparison to Amiodarone

BACKGROUND Dysfunction of small conductance calcium activated potassium (SK) channels plays a vital role in atrial arrhythmogenesis. Amiodarone and dronedarone are the most effective class III antiarrhythmic drugs. It is unclear whether the antiarrhythmic effect of amiodarone and dronedarone is related to SK channel inhibition. MATERIAL AND METHODS Tissue samples were obtained from the right atria of 46 patients with normal sinus rhythm and 39 patients with chronic atrial fibrillation. Isolated atrial myocytes were obtained by enzymatic dissociation. KCNN2 (SK2) channels were transiently expressed in human embryonic kidney (HEK)-293 cells. SK currents were recorded using whole-cell conventional patch clamp techniques. RESULTS Amiodarone and dronedarone showed a concentration-dependent inhibitory effect on SK currents (IKAS) in atrial myocytes from normal sinus rhythm patients and chronic atrial fibrillation patients. The suppressed efficacy of dronedarone and amiodarone on IKAS was greater in atrial myocytes from chronic atrial fibrillation patients than that from normal sinus rhythm patients. Furthermore, in patients with chronic atrial fibrillation, the IC₅₀ value was 2.42 µM with dronedarone and 8.03 µM with amiodarone. In HEK-293 cells with transiently transfected SK2 channels, both dronedarone and amiodarone had a dose-dependent inhibitory effect on IKAS. The IC₅₀ value was 1.7 µM with dronedarone and 7.2 µM with amiodarone in cells from patients with chronic atrial fibrillation. Compared to amiodarone, dronedarone is more efficacy to inhibit IKAS and could be a potential intervention for patients with chronic atrial fibrillation. CONCLUSIONS Dronedarone provides a great degree of IKAS inhibition in atrial myocytes from chronic atrial fibrillation than amiodarone. IKAS might be a potential target of amiodarone and dronedarone for the management of chronic atrial fibrillation.

Lithium-associated hypothyroidism and potential for reversibility after lithium discontinuation: Findings from the LiSIE retrospective cohort study

BACKGROUND

The association between lithium and thyroid dysfunction has long been known. However, it remains unknown if lithium-associated hypothyroidism is reversible once lithium treatment has been stopped.

AIMS

To determine whether lithium-associated hypothyroidism was reversible in patients who subsequently discontinued lithium.

METHODS

A retrospective cohort study in the Swedish region of Norrbotten into the effects and side- effects of lithium treatment and other drugs for relapse prevention (Lithium - Study into Effects and Side Effects). For this particular study, we reviewed medical records between 1997 and 2015 of patients with lithium-associated hypothyroidism who had discontinued lithium.

RESULTS

Of 1340 patients screened, 90 were included. Of these, 27% had overt hypothyroidism at the start of thyroid replacement therapy. The mean delay from starting lithium to starting thyroid replacement therapy was 2.3 years (SD 4.7). In total, 50% of patients received thyroid replacement therapy within 10 months of starting lithium. Of 85 patients available for follow-up, 41% stopped thyroid replacement therapy after lithium discontinuation. Only six patients reinstated thyroid replacement therapy subsequently. Of these, only one had overt hypothyroidism.

CONCLUSIONS

Lithium-associated hypothyroidism seems reversible in most patients once lithium has been discontinued. In such cases, thyroid replacement therapy discontinuation could be attempted much more often than currently done. Based on the limited evidence of our study, we can expect hypothyroidism to recur early after thyroid replacement therapy discontinuation, if at all.

Comorbidities in chronic heart failure: An update from Italian Society of Cardiology (SIC) Working Group on Heart Failure

The increasing number of patients with heart failure HF and comorbidities is due to aging population and increase of life expectancy of patients with cardiovascular disease. Encouraging results derived by recent trials may suggest some comorbidities as new targets for new drugs, highlighting the need for a better understanding of the comorbidities' effects in HF patients and the need of a multidisciplinary approach for the management of chronic HF with comorbidities. We report a brief review about main cardiovascular and non-cardiovascular comorbidities in HF patients in order to update physicians and researchers engaged in the HF research or in "fight against heart failure."

The Effects of Amiodarone on Thyroid Function in Pediatric and Young Adult Patients

CONTEXT

Amiodarone is used in patients with arrhythmias, but thyroid dysfunction [amiodarone-induced thyrotoxicosis (AIT) or amiodarone-induced hypothyroidism (AIH)] is a common adverse effect. As the onset of AIT and AIH has not been studied in children, the timing of dysfunction and long-term monitoring are not known in this population.

OBJECTIVE

To describe the incidence and timing of amiodarone-induced thyroid dysfunction in children and adolescents, with a secondary aim to identify risk factors for amiodarone-induced thyroid dysfunction, and to identify variance in thyroid hormone surveillance and treatment.

DESIGN

Retrospective review of thyroid dysfunction in children and young adults treated with amiodarone between 2007 and 2018.

SETTING

Children's Hospital of Philadelphia.

PATIENTS

Children and young adults treated with amiodarone.

MAIN OUTCOME MEASURES

Prevalence of amiodarone-induced thyroid dysfunction.

RESULTS

Of 484 patients, 190 had thyroid-function testing; 17.3% were found to have subclinical hypothyroidism, and 13.7% testing developed hypothyroidism. Hyperthyroidism occurred in 2.1%. In patients with subclinical hypothyroidism, 63% returned to normal thyroid function without thyroid hormone replacement. Only 26% of patients with hypothyroidism had spontaneous normalization of thyroid function. Twenty-five percent of AIT patients had spontaneous normalization of thyroid function.

CONCLUSIONS

This study looks at a pediatric and young-adult population in an effort to describe the natural history of amiodarone-induced thyroid dysfunction. Based on our data, we recommend that a complete thyroid-function panel be obtained within the first week and then at weekly intervals for the first 5 weeks after initiation. The majority of thyroid dysfunction was noted within the first 35 days of treatment.

Amiodarone-induced thyrotoxicosis in a pediatric patient: A rare and demanding clinical case

Thyroid dysfunction is one of the most common adverse effects of amiodarone therapy, ranging from subclinical changes to overt clinical thyrotoxicosis (AIT) and/or hypothyroidism. Due to its heterogeneity, AIT lasts as a defiant entity, leading to a thorny treatment course, particularly in pediatrics. AIT can be classified as either type 1, type 2 or mixed form based on its pathophysiology. Differentiating between the main AIT subtypes is quite relevant, since there is specific treatment for both, however, this distinction may be difficult in clinical practice. We describe a rare case of AIT in a pediatric patient, with an uncommon congenital cardiac malformation, that started amiodarone therapy due to paroxysmal supraventricular tachycardia. AIT was reported 26 months after drug onset, with a sudden and explosive emerging. This case highlights the current AIT management challenges on the highdemanding pediatric field pursuing, ultimately, an enhanced patient´s care.

Effectiveness of amiodarone in treatment of cutaneous leishmaniasis caused by Leishmania major

Development of new chemotherapeutic agents is an essential issue in the treatment and control of a disease. This study aimed to evaluate the anti-leishmanial activity of amiodarone, an antiarrhythmic class III drug, against Leishmania major, the most prevalent etiological agent of cutaneous leishmaniasis in the old world. The proliferation of promastigotes and intracellular amastigotes in the absence or presence of amiodarone was estimated, in an in vitro study. For in vivo study, five weeks after infection of BALB/c mice with L. major, when the lesions appeared at the injection site, the mice were divided into four groups (n = 6 each); treatment was conducted for 28 consecutive days with vehicle, amiodarone at 40 mg/kg orally and glucantime at 60 mg/kg intraperitoneally. Therapy with amiodarone reduced the size of lesions compared to the untreated group after 12 days. Amiodarone decreased the parasite load and inflammatory responses, particularly the macrophages containing amastigotes, and enhanced granulation tissue formation in the dermis and subcutaneous area. The Tumor necrosis factor-α and Interleukin-6 levels were significantly lower in the cell culture supernatants of the inguinal lymph node in the amiodarone treated group compared to the vehicle and untreated groups. Amiodarone significantly increased the activity of glutathione peroxidase in comparison to the vehicle and untreated groups but did not affect the plasma levels of superoxide dismutase, malondialdehyde, adiponectin, and ferric reducing ability of plasma. Therefore, the anti- L. major activity and immunomodulatory effects of amiodarone reduced the parasitic load and enhanced wound healing in cutaneous leishmaniasis in BALB/c mice. Amiodarone reduced the lesion surface area, but it did not cure it completely.

Thyrotoxicosis with concomitant thyroid cancer

Thyrotoxicosis with concomitant thyroid cancer is rare and poorly recognized, which may result in delayed diagnosis, inappropriate treatment and even poor prognosis. To provide a comprehensive guidance for clinicians, the etiology, pathogenesis, diagnosis and treatment of this challenging setting were systematically reviewed. According to literatures available, the etiologies of thyrotoxicosis with concomitant thyroid cancer were categorized into Graves' disease with concurrent differentiated thyroid cancer (DTC) or medullary thyroid cancer, Marine-Lenhart Syndrome with coexisting DTC, Plummer's disease with concomitant DTC, amiodarone-induced thyrotoxicosis with concomitant DTC, central hyperthyroidism with coexisting DTC, hyperfunctioning metastases of DTC and others. The underlying causal mechanisms linking thyrotoxicosis and thyroid cancer were elucidated. Medical history, biochemical assessments, radioiodine uptake, anatomic and metabolic imaging and ultrasonography-guided fine-needle aspiration combined with pathological examinations were found to be critical for precise diagnosis. Surgery remains a mainstay in both tumor elimination and control of thyrotoxicosis, while anti-thyroid drugs, beta-blockers, 131I, glucocorticoids, plasmapheresis, somatostatin analogs, dopamine agonists, radiation therapy, chemotherapy and tyrosine kinase inhibitors should also be appropriately utilized as needed.

Frequent ventricular extrasystoles after heart transplantation: a late presentation of amiodarone-induced thyrotoxicosis: a case report

Background

There is a lack of information about a mixed type of amiodarone-induced thyrotoxicosis (AIT) after heart transplantation (HTx) with no amiodarone treatment in almost 1 year. Frequent ventricular extrasystoles (VES) associated with a mixed type of AIT can often be treated using thiamazole and prednisolone, without the need for specific antiarrhythmic treatment.

Case summary

We present a clinical case of a 65-year-old heart transplanted male patient with frequent VES associated with mixed type of AIT. Recipient had managed with amiodarone prior to HTx but there were no indications for it after the surgery. One year after antiarrhythmic treatment was discontinued, monomorphic VES (total amount: 27 472/day) were diagnosed. In addition, our investigation revealed that thyrotoxicosis developed. Prednisolone and thiamazole were added to the treatment with positive outcomes. The antithyroid treatment had been discontinued after 9 months and results of the 24-h Holter electrocardiogram monitoring showed only two VES/24 h.

Discussion

The case highlights the association of amiodarone, thyroid disorders, and VES. In mixed type AIT or if diagnosis is uncertain, it is reasonable to use mixed therapy. Next is to decide whether you need special treatment for VES. There was no evidence of ventricular tachycardia. Thyroid function tests remained normal off antithyroid medications and the total amount of VES significantly decreased. There were no indications for any antiarrhythmic treatment or ablation.

Syndrome of thyrotoxicosis. Differential diagnosis and treatment

Since the middle of the twentieth century, there has been a significant change in methods of the diagnosis and treatment of thyroid diseases with thyrotoxicosis syndrome. Previously doctors did not have trouble just with diagnosing diseases that occur with a typical clinical presentation (the Merzeburg triad, a multinodal goiter with fibrillation) because of no possible to determine thyroid hormones. Then in the early 70s years the appearance of immunological methods for estimating hormones in the blood has led to significant changes in our understanding of the variants of thyroid pathology with thyrotoxicosis (TT). Today, the diagnosis of the fact of thyrotoxicosis as a whole is not difficult (except for the confusion of preanalytical errors), but differential diagnosis within the declared syndrome remains extremely relevant to this day. Unfortunately, in the minds of many doctors, these diseases are sometimes perceived as a whole, and in the conditions of the "century of speeds", a modern doctor, extremely limited in time, often unjustifiably prescribes thyreostatic therapy, treatment with radioactive iodine or even surgical intervention after detecting thyrotoxicosis. The old truth "remember that a patient with thyrotoxicosis is a person with a sick heart..." has not lost relevance today. It is very important for the practicing physician be able to navigate in the spectrum of pathologies manifested by the thyrotoxicosis pattern because of the influence of excess thyroid hormones on the cardiovascular system and the hemostasis system. Hereinafter we tried to show diagnostic aspects focusing on differences in pathologies with TT syndrome in a lot of thyroid diseases and even nonthyroid diseases.

Amiodarone and thyroid physiology, pathophysiology, diagnosis and management

Although amiodarone is considered the most effective antiarrhythmic agent, its use is limited by a wide variety of potential toxicities. The purpose of this review is to provide a comprehensive "bench to bedside" overview of the ways amiodarone influences thyroid function. We performed a systematic search of MEDLINE to identify peer-reviewed clinical trials, randomized controlled trials, meta-analyses, and other clinically relevant studies. The search was limited to English-language reports published between 1950 and 2017. Amiodarone was searched using the terms adverse effects, hypothyroidism, myxedema, hyperthyroidism, thyroid storm, atrial fibrillation, ventricular arrhythmia, and electrical storm. Google and Google scholar as well as bibliographies of identified articles were reviewed for additional references. We included 163 germane references in this review. Because amiodarone is one of the most frequently prescribed antiarrhythmic drugs in the United States, the mechanistic, diagnostic and therapeutic information provided is relevant for practicing clinicians in a wide range of medical specialties.

Emerging role of amiodarone and dronedarone, as antiarrhythmic drugs, in treatment of leishmaniasis

Leishmaniasis is a group of human and animal diseases causing 20,000-40,000 annual deaths and its etiological agents belong to the Leishmania genus. The most current treatment against leishmaniasis is chemotherapy. Pentavalent antimonials such as glucantime and pentostam have been administrated as the first-line drugs in treatment of various forms of leishmaniasis. The second-line drugs such as amphotericin B, liposomal amphotericin B, miltefosine, pentamidine, azole drugs and paromomycin are used in resistant cases to pentavalent antimonials. Because of drawbacks of the first-line and second-line drugs including adverse side effects on different organs, increasing resistance, high cost, need to hospitalization and long-term treatment, it is necessary to find an alternative drug for leishmaniasis treatment. Several investigations have reported the effectiveness of amiodarone, the most commonly used antiarrhythmic drug, against fungi, Trypanosomes and Leishmania spp. in vitro, in vivo and clinical conditions. Moreover, the beneficial effects of dronedarone, amiodarone analogues, against Trypanosoma cruzi and Leishmania mexicana have recently been demonstrated and such treatment regimens resulted in lower side effects. The anti- leishmanial and anti- trypanosomal effectiveness of amiodarone and dronedarone has been attributed to destabilization of intracellular Ca²⁺ homeostasis, inhibition of sterol biosynthesis and collapse of mitochondrial membrane potential. Because of relative low cost, excellent pharmacokinetic properties, easy accessibility and beneficial effects of amiodarone and dronedarone on leishmaniasis, they are proper candidates to replace the current drugs used in leishmaniasis treatment.

The role of mast cells and macrophages in amiodarone induced pulmonary fibrosis and the possible attenuating role of atorvastatin

Amiodarone (AM) is an effective anti-arrhythmic drug. We investigated the role of mast cells and macrophages on AM induced pulmonary fibrosis and the action of atorvastatin on this fibrosis. Rats were allocated into four groups; negative control (1), positive control (2), 30 mg/kg body weight/day AM (3) and AM + 10 mg/kg/day atorvastatin (4). Lungs were harvested and prepared for histology and immunohistochemistry. Hematoxylin and eosin stained sections of group 3 exhibited disorganized lung architecture. We found cellular debris in the lumen of both intrapulmonary bronchi and bronchioles with partial disruption of the thickened epithelial lining and mononuclear cellular infiltration into the lamina propria. We also observed thickening of the epithelial lining and the smooth muscle layer. Congested, dilated and thickened blood capillaries and thickened inter-alveolar septa were observed with mononuclear cellular infiltrates in the lung of group 3. Most alveoli were collapsed, but some dilated ones were detected. In some alveoli, type ІІ pneumocytes were increased, while type I cells were decreased. We observed significant increases in the amount of collagen in the thickened inter-alveolar septa, around bronchioles and around blood capillaries in sections from group 3. We found a significant increase in mast cells and alveolar macrophages in group 3 compared to group 1. Mast cells and macrophages appear to play important roles in AM induced pulmonary fibrosis. Atorvastatin appears to attenuate this condition.

Amiodarone-related thyroid dysfunction

Nowadays, amiodarone is the most commonly used antidysrhythmic drug in clinical practice. It is highly effective in the management of recurrent ventricular dysrhythmias, paroxysmal supraventricular dysrhythmias, including atrial fibrillation and flutter, and in the maintenance of sinus rhythm after electrical cardioversion of atrial fibrillation. Moreover, it has the added benefit of being well tolerated in patients with both normal and impaired left ventricular systolic function. Despite amiodarone's potent antidysrhythmic actions, its use is hampered by numerous adverse effects on various organs, including the thyroid. Adverse effects are becoming more prevalent given the increasing incidence of dysrhythmias and wider amiodarone use. Thus, physicians and patients should both be aware of the potential thyroid-specific sequelae. However, amiodarone is likely to remain a significant problem for endocrinologists as concerns exist over the use of the new alternative antiarrhythmic agent, dronedarone, especially in patients with heart failure and left ventricular dysfunction because of the risk of hepatic injury and increased mortality. The final diagnostic and therapeutic approaches must be discussed among the patient, the general practitioner, the cardiologist, and the endocrinologist.

Relation between Endogenous Stem Cells and Green Tea Extract in Overconsumption and Amiodarone Induced Thyroid Damage in Rat

BACKGROUND AND OBJECTIVES

Amiodarone (AM), one of the most commonly prescribed antiarrhythmics, is frequently associated with thyroid dysfunction. Green tea extract (GTE) supplementation would attenuate oxidative stress and activate progenitor cells. However, the potential toxicity of GTE on various organs when administered at high doses has not been completely investigated. The present study aimed at investigating the possible relation between endogenous stem cells and GTE in overconsumption and AM induced thyroid damage in albino rat.

METHODS AND RESULTS

Twenty four male albino rats were divided into control group, GTE group (rats given 50 mg/kg), Overconsumption group (rats given 1,000 mg/kg GTE), AM group (rats given 30 mg/kg) and combined AM, GTE therapy group. AM and GTE were administered orally 5 days/week for 8 weeks. Serological tests were performed. Thyroid sections were exposed to histological, immunohistochemical and morphometric studies. In overconsumption group, multiple distorted follicles with cellular debris in the lumen and multiple follicles devoid of colloid were found. In AM group, multiple follicles exhibiting crescent of colloid and few follicles devoid of colloid were detected. In combined therapy group, multiple follicles were filled with colloid. Significant decrease in area of colloid and significant increase in the area% of collagen were recorded in overconsumption and AM groups. Area% of CD 105 +ve cells denoted significant increase in combined therapy group. Serological tests were confirmative.

CONCLUSIONS

Endogenous SCs activation was proved in AM and GTE combined therapy group with regression of AM induced morphological, morphometric and serological changes. However, overconsumption of GTE recruited endogenous SCs suppression.