Thyroid function and thyroid regulation in euthyroid men with chronic liver disease: evidence of multiple abnormalities

Endocrine Diseases and the Liver: An Update

The endocrine system is a complex interconnected system of organs that control corporeal processes and function. Primary endocrine organs are involved in hormonal production and secretion but rely on a bevy of signals from the hypothalamic-pituitary axis and secondary endocrine organs, such as the liver. In turn, proper hepatic function is maintained through hormonal signaling. Thus, the endocrine system and liver are codependent, and diseases affecting either organs can lead to alterations in function within their counterparts. This article explores the hepato-endocrine relationship, including the effects on endocrine diseases on the liver.

Evaluation of blood metabolites reflects presence or absence of liver abscesses in beef cattle

Liver abscesses constitute a prominent concern regarding animal health and profitability of the beef industry. Our objective was to evaluate potential biliary and blood indicators of liver abscesses. Twenty-nine beef bulls (initially averaging 356±70.5 kg and 253±30 days of age) were fed a high-concentrate diet during a performance test of 112 days, during which blood was collected at nine time points spaced 0.5-13 days apart within 56 days before slaughter. At the abattoir, blood and bile were collected and livers were inspected for liver abscesses. Results indicated that liver abscesses are associated with elevated levels of plasma cortisol and aspartate aminotransferase, and decreased levels of albumin, cholesterol and testosterone over the period before slaughter. Based on the blood samples collected during exsanguination, the presence of liver abscesses was associated with lower concentrations of thyroxine, albumin, cholesterol and alkaline phosphatase, and is suggested to be associated with lower blood carbon dioxide (P=0.08) and lower biliary cortisol metabolites (P=0.07). Albumin and cholesterol are established indicators of hepatic function and are consistently related to the presence of liver abscesses. Identifying blood parameters that predict liver abscesses has practical implications for cattle husbandry and for ensuring food safety.

Relationship between vitamin A deficiency and the thyroid axis in clinically stable patients with liver cirrhosis related to hepatitis C virus

Vitamin A deficiency (VAD) and altered thyroid function are commonly encountered in patients with liver cirrhosis. The link between vitamin A metabolism and thyroid function has been previously identified. The aim of this study was to explore the association between VAD and the thyroid axis in clinically stable patients with cirrhosis related to hepatitis C virus (HCV). One hundred and twelve patients with clinically stable HCV-related cirrhosis and 56 healthy controls matched for age, sex, and socioeconomic status were recruited for this study. Vitamin A status, liver function, thyroid-stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), reverse triiodothyronine (rT3), anti-thyroid peroxidase antibodies (anti-TPO), and thyroid volume were evaluated. The prevalence of VAD among patients with HCV-related cirrhosis was 62.5% compared with 5.4% among controls (P < 0.001). Patients with HCV-related cirrhosis had significantly higher FT4, FT3, TSH, and thyroid volume than did healthy controls. Of the 112 patients initially recruited, 18 were excluded (patients with subclinical hypothyroidism and/or anti-TPO positive), so a total of 94 patients with HCV-related cirrhosis were divided into 2 groups according to vitamin A status: VAD and normal vitamin A. Patients with VAD had significantly lower vitamin A intake and serum albumin and higher serum bilirubin, FT4, FT3, and TSH than patients with normal vitamin A status. Multiple logistic regression analysis revealed that VAD was associated with Child-Pugh score (β = 0.11, P = 0.05) and TSH (β = -1.63, P = 0.02) independently of confounding variables. We conclude that VAD may be linked to central hyperthyroidism in patients with clinically stable HCV-related liver cirrhosis.

The influence of end-stage liver disease and liver transplantation on thyroid hormones

BACKGROUND

Thyroid dysfunction has been reported in most chronic illnesses including severe liver disease. These defects in thyroid hormone metabolism result in the sick euthyroid syndrome, also known as low T3 syndrome.

OBJECTIVES

Our objective was to evaluate the thyroid function in patients with end stage liver disease prior and after deceased donor liver transplantation and to correlate thyroid hormonal changes with the MELD score (Model for End stage Liver Disease).

METHODS

In a prospective study, serum levels of thyrotropin (thyroid stimulating hormone TSH), total thyroxine (tT4), free thyroxine (fT4) and triiodothyronine (T3) from 30 male adult patients with end stage liver disease were measured two to four hours before and 6 months after liver transplantation (LT). MELD was determined on the day of transplant. For this analysis, extra points were not added for patients with hepatocellular carcinoma.

RESULTS

The patients had normal TSH and fT4 levels before LT and there was no change after the procedure. Total thyroxine and triiodothyronine were within the normal range before LT, except for four patients (13.3%) whose values were lower. Both hormones increased to normal values in all four patients after LT (P=0.02 and P<0.001, respectively). When the patients were divided into two groups (MELD <18 and MELD >18), it was observed that there was no change in the TSH, freeT4, and total T4 levels in both groups after LT. Although there was no significant variation in the level of T3 in MELD <18 group (P=0.055), there was an increase in the MELD >18 group after LT (P=0.003).

CONCLUSION

Patients with end stage liver disease subjected to liver transplantation had normal TSH and fT4 levels before and after LT. In a few patients with lower tT4 and T3 levels before LT, the level of these hormones increased to normal after LT.

Liver injury correlates with biomarkers of autoimmunity and disease activity and represents an organ system involvement in patients with systemic lupus erythematosus

Liver disease (LD), defined as ≥ 2-fold elevation of aspartate aminotransferase (AST) or alanine aminotransferase (ALT), was examined in a longitudinal study of systemic lupus erythematosus (SLE) patients. Among 435 patients, 90 (20.7%) had LD with a greater prevalence in males (15/39; 38.5%) than females (75/396; 18.9%; p = 0.01). SLE disease activity index (SLEDAI) was greater in LD patients (7.8 ± 0.7) relative to those without (5.8 ± 0.3; p = 0.0025). Anti-smooth muscle antibodies, anti-DNA antibodies, hypocomplementemia, proteinuria, leucopenia, thrombocytopenia, and anti-phospholipid syndrome were increased in LD. An absence of LD was noted in patients receiving rapamycin relative to azathioprine, cyclosporine A, or cyclophosphamide. An absence of LD was also noted in patients treated with N-acetylcysteine. LFTs were normalized and SLEDAI was diminished with increased prednisone use in 76/90 LD patients over 12.1 ± 2.6 months. Thus, LD is attributed to autoimmunity and disease activity, it responds to prednisone, and it is potentially preventable by rapamycin or N-acetylcysteine treatment.

Thyroid hormone levels in children with liver cirrhosis awaiting a liver transplant

OBJECTIVES

Evidence exists that decreased in triiodothyronine (T3) and thyroxine (T4) levels are associated with the severity of liver disease, and these hormones could be used as disease prognostic factors, but there are paradoxes in this regard in the literature. This study aimed at evaluating the correlation between thyroid hormone levels and severity of liver disease.

MATERIALS AND METHODS

We measured thyroid hormone levels in 83 children with liver cirrhosis using radioimmunoassay techniques.

RESULTS

Four patients (4.8%) showed a decrease in the amount of T3 and 9 patients (10.8%) revealed increased levels of T3. Also, decreases were seen in the T4 levels of 7 patients (8.4%), and 4 patients (4.8%) showed increases in levels of T4. The serum albumin levels were lower and international normalized ratio was higher in patients with low T3 and low T4. This study reveals that the Model for End-Stage Liver Disease and Pediatric End-Stage Liver Disease scores are statistically related to the decreased amounts of T4 (P = .036). The Model for End-Stage Liver Disease and Pediatric End-Stage Liver Disease scores and the Child scores were higher in low T3 patients, but this was not significant (P > .05).

CONCLUSIONS

Decreased levels of thyroid hormones are correlated with the severity of disease and can be seen in more advanced cirrhosis. Patients with decreased T4 levels need a liver transplant more immediately than those patients that do not have decreased T4 levels.

Inverse association between serum free thyroxine levels and hepatic steatosis: results from the Study of Health in Pomerania

BACKGROUND

Associations between thyroid function and hepatic steatosis defined by enzymatic and sonographic criteria are largely unknown in the general population. Thus, the aim of the present study was to investigate the association between thyroid function tests and sonographic as well as enzymatic criteria of liver status in a large population-based study, the Study of Health in Germany (SHIP).

METHODS

Data from 3661 SHIP participants without a self-reported history of thyroid or liver disease were analyzed. Hepatic steatosis was defined as the presence of a hyperechogenic ultrasound pattern of the liver and increased serum alanine transferase concentrations. Serum thyroid-stimulating hormone (TSH), free triiodothyronine (FT3), and free thyroxine (FT4) concentrations were associated with hepatic steatosis using multinomial regression models adjusted for sex, age, physical activity, alcohol consumption, waist circumference, and food intake pattern.

RESULTS

We detected no consistent association of serum TSH and FT3 concentrations with hepatic steatosis. In contrast, serum FT4 concentrations were inversely associated with hepatic steatosis in men (odds ratio (OR)=0.04 [95% confidence interval (CI)=0.01; 0.17]) and women (OR=0.06 [95% CI=0.01; 0.42]).

CONCLUSIONS

Results from the present cross-sectional study suggest that low FT4 concentrations are associated with hepatic steatosis. Longitudinal and intervention studies are warranted to investigate whether hypothyroidism increases the risk of hepatic steatosis or vice versa.

Oxidative stress and thyroid hormones in patients with liver diseases

BACKGROUND

The liver metabolizes the thyroid hormones and regulates their systemic endocrine effects so liver disease could affect thyroid hormone metabolism. Oxidative stress could play a role in the pathogenesis and progression of liver diseases. The objective of this study was to investigate serum levels of oxidative stress and antioxidant in liver diseases as prognostic markers and know the importance of these antioxidants level in relation to thyroid hormones.

METHODS

Serum nitric oxide (NO), malondialdehyde (MDA) and triiodothyronine (T(3)), thyroxine (T(4)), thyroid stimulating hormone (TSH), apolipoprotein-1 (APOA1) levels and erythrocyte reduced glutathione (GSH) level and glutathione peroxidase (GSHPx) and glutathione reductase (GR) activities were determined in 20 control subjects, 13 patients with non-alcoholic steatohepatitis (NASH), 18 patients with chronic HCV, 17 patients with compensated cirrhotic HCV and 42 patients with decompensated cirrhotic HCV.

RESULTS

Cirrhotic patients with HCV had higher NO and MDA levels while lower T(3) and erythrocyte GSH levels, and GSHPx activity than the chronic. Serum T(3) showed negative correlation with serum NO and MDA whereas positive correlation with APOA1, GSH, and GSHPx in cirrhotic patients with HCV.

CONCLUSION

The measurement of the total T(3), NO, MDA, GSH reduced and GSHPx as biomarkers for liver diseases might be a beneficial tool, helping in monitoring the state of liver disease patients.

Assessment of thyroid function in chronic alcoholics

The clinical manifestations in chronic alcoholics may sometimes mimic those of hyperthyroidism. However, diagnostic aids are somewhat contradictory in many cases. Ten chronic alcoholics with symptoms from the sympathoadrenal system were investigated. A significant increase (p less than 0.01) of T3 at 120 min after TRH stimulation was found despite a blunted TSH response (increment less than 3 mU/l) in some cases. This increase in T3 indicates a preserved thyroid function in chronic alcoholics despite generally low basal T3 levels. It is concluded that T3 determinations at 120 min in connection with TRH test may be an essential parameter in evaluating euthyroid function in chronic alcoholics.

[Thyroid function tests in viral chronic hepatitis]

BACKGROUND

One hundred and twenty five patients with virus B or C chronic active hepatitis and postnecrotic cirrhosis and different degrees of liver dysfunction were studied.

AIM

1) To determine a thyroid hormonal profile; 2) to evaluate the prognostic value of these tests in relation to the progression of the disease and mortality; 3) compare these findings with Child-Pugh classification.

PATIENTS AND METHODS

The patients were divided in four groups: a) 31 with chronic active hepatitis; b) 41 with postnecrotic cirrhosis Child A; c) 35 with postnecrotic cirrhosis Child B and d) 18 with postnecrotic cirrhosis Child C. The protocol comprised serum measurements of albumin and bilirrubin, estimates of prothrombin time and clinical evaluation of ascites and encephalopathy, measurement of total serum triiodothyronine, thyroxine, thyroid-stimulating hormone, free thyroxine, reverse triiosothyronine, calculated rT3/T3 index (IrT3) and thyrotropin-releasing hormone test.

RESULTS

Total serum triiodothyromnine showed the most significant difference among the groups, gradually lower as the disease became more advanced (CAH: 149.2 +/- 42.3 ng/dL; PNC-A: 137.4 +/- 37.2 ng/dL; PNC-B: 88.0 +/- 28.4 ng/dL and PNC-C: 41.8 +/- 21.9 ng/dL). Low levels of T4 (4.5 +/- 2.0 micrograms/dL) and FT4 (0.7 +/- 0.4 ng/dL) and elevated levels of thyroid-stimulating hormone (7.2 +/- 11.5 microIU/mL), reverse triiosothyronine (60.8 +/- 52.1 ng/dL) and calculated rT3/T3 index (2.2 +/- 2.6) were more frequent in patients with postnecrotic cirrhosis Child C. Thyrotropin-releasing hormone test was normal in the majority of the patients.

CONCLUSION

The present study shows a positive relationship between the low serum levels of T3 and elevated serum levels of rT3 and IrT3/T3 with the degree of hepatic dysfunction according to the Child-Pugh classification.

Nutritional and prognostic significance of serum hypothyroxinemia in hospitalized patients with liver cirrhosis

BACKGROUND/AIMS

A variety of severe illnesses can induce changes in thyroid hormone metabolism, leading to findings referred to as "sick euthyroid syndrome". In several groups of patients the reduction of serum thyroxine concentration (T4), characteristic of the low-T4 variant of sick euthyroid syndrome, has been found to be a good predictor of survival. Although the pathophysiology of hormonal alterations has not yet been defined, nutritional deficits have been suggested to play a role. The study aimed to define the prognostic and nutritional significance of serum thyroxine in liver cirrhosis.

METHODS

Thyroid hormones and nutritional status were evaluated in a group of 75 consecutive hospitalized patients with cirrhosis, followed-up clinically for 12 months.

RESULTS

A low-T4 variant of sick euthyroid syndrome was found in 23 of the 75 enrolled patients with cirrhosis (30.6%). Serum T4, but not serum T3, correlated with mid-arm muscle circumference (p < 0.01), an indicator of muscle protein compartment. While both serum T3 and T4 correlated directly with serum proteins and inversely with Child-Pugh score, only T4 was predictive of outcome. Patients with the low-T4 variant of sick euthyroid syndrome showed significantly lower short- and long-term survival rates compared to those with normal serum T4 concentrations (p < 0.008 at 3 months, p < 0.001 at 6 months and 1 year). A multivariate analysis using the proportional hazards Cox's regression procedure showed that serum T4, but not serum T3 or nutritional parameters, improves the prognostic capacity of Child-Pugh score (p < 0.01).

CONCLUSIONS

These data indicate that the low T4-variant of sick euthyroid syndrome distinguishes a subgroup of patients with cirrhosis at risk for decreased survival. The inclusion of T4 in the Child-Pugh score, by improving its prognostic power, may optimize the selection of patients with advanced cirrhosis to receive specific therapy such as transplantation.

Clinical associations between thyroid and liver diseases

The liver has an important role in thyroid hormone metabolism and the level of thyroid hormones is also important to normal hepatic function and bilirubin metabolism. Besides the associations between thyroid and liver diseases of an autoimmune nature, such as that between primary biliary cirrhosis and hypothyroidism, thyroid diseases are frequently associated with liver injuries or biochemical test abnormalities. For example, thyroid diseases may be associated with elevation of alanine aminotransferase and alkaline phosphatase, which is mainly of bone origin, in hyperthyroidism and aspartate aminotransferase in hypothyroidism. Liver diseases are also frequently associated with thyroid test abnormalities or dysfunctions, particularly elevation of thyroxine-binding globulin and thyroxine. Hepatitis C virus infection has been connected with thyroid abnormalities. In addition, antithyroid drug therapy may result in hepatitis, cholestasis or transient subclinical hepatotoxicity, whereas interferon (IFN) therapy in liver diseases may also induce thyroid dysfunctions. These thyroid-liver associations may cause diagnostic confusions. Neglect of these facts may result in over of under diagnosis of associated liver or thyroid diseases and thereby cause errors in patient care. It is suggested to measure free thyroxine (FT4) and thyroid-stimulating hormone (TSH) which are usually normal in euthyroid patients with liver disease, to rule out or rule in coexistent thyroid dysfunctions, and consider the possibility of thyroid dysfunctions in any patients with unexplained liver biochemical test abnormalities. It is also advisable to monitor patients with autoimmune liver disease or those receiving IFN therapy for the development of thyroid dysfunctions, and patients receiving antithyroid therapy for the development of hepatic injuries.

Thyroid function and serum IGF-1 in children before and after liver transplantation

We report results of serum thyroid hormone and IGF-1 concentrations in 20 children, 1.2 to 13.6 years old, with various degrees of chronic liver dysfunction (CLD), before and after successful orthotopic liver transplantation (OLT). Ten children presented with moderate chronic liver disease (CLD-M) with prothrombin time (PT) > 50% and serum albumin concentration > 3 g/dl; 7 children had severe chronic liver disease (CLD-S) with PT < 50% and serum albumin concentration < 3 g/dl; and 7 children who had received an OLT, who had normal liver function at the time of the study. Four of the latter group were also studied before OLT. Patients with CLD-M had normal mean +/- SD serum levels of total T3 (2.0 +/- 0.7 nmol/l), total T4 (125 +/- 25.9 nmol/l) and fT4 concentrations (16 +/- 2.8 pmol/l). In contrast, children with CLD-S showed a significant decrease in thyroid hormones together with normal basal TSH values (T3 0.8 +/- 0.0 nmol/l; T4 45.6 +/- 19.5 nmol/l; fT4 7.4 +/- 1.1 pmol/l; TSH 3.8 +/- 0.9 mU/l). Patients who received a successful OLT showed mean peripheral thyroid hormone concentrations significantly higher than CLD-S patients (T3 1.7 +/- 0.7 nmol/l, p < 0.005; T4 92.8 +/- 18.2 nmol/l, p < 0.001; fT4 14.5 +/- 3.1 pmol/l, p < 0.001). A significant correlation was found between thyroid hormone levels and PT or serum albumin. In the nine patients with CLD-M and CLD-S in whom serum IGF-1 concentration was measured, values found (mean +/- SD 0.08 +/- 0.05 U/ml) were below the 95% confidence limit of matched controls.

Hypothalamic-pituitary-thyroid (HPT) axis in chronic alcoholism. I. HPT axis in chronic alcoholics during withdrawal and after 3 weeks of abstinence

Thyroxine (T4), free T4 (fT4), triiodothyronine (T3), free T3 (fT3), reverse T3 (rT3), thyrotropin (TSH), thyroxine binding globulin (TBG), and T3 uptake were measured in 14 chronic alcoholics during withdrawal and after 21 days of abstinence. Results were compared with those of 16 healthy volunteers. During withdrawal, the fT4 and fT3 concentrations were subnormal, whereas the respective protein-bound fractions were normal. T4, T3, and TBG increased during the abstinence period, T3 and TBG being significantly higher than in normals at the second measuring time. T3 uptake values fell, but remained well within the normal range at both measuring times. During abstinence, the fT3 levels remained significantly lower than in healthy subjects. rT3 concentrations decreased, but not significantly. The TSH values were normal throughout. These results showed numerous abnormalities in the hypothalamic-pituitary-thyroid axis in alcoholics, the reasons for which are as yet unclear. The following possible interpretations are suggested: 1. The abnormally low serum fT3 and fT4 levels during withdrawal might reflect an increase in tissue uptake. 2. The increases in T4--and partly those in T3--during abstinence seem to reflect increased binding by TBG, the level of which rose markedly for reasons as yet unknown. 3. If increases in TBG during abstinence are taken into account, the decreases in rT3 concentrations may reach the level of statistical significance. These falls in rT3 concentrations may reflect an increase in rT3 metabolization (deiodination) in various tissues, including the CNS, leading to a reduction in serum rT3 bioavailability. 4. Factors such as liver disease, protein caloric malnutrition, and "psychological stress" do not fully explain all these abnormalities. A direct effect of ethanol on intracellular thyroid hormone metabolism and/or function seems conceivable.

Severity of alcoholic liver disease and markers of thyroid and steroid status

Alcoholic liver disease is associated with abnormalities in circulating levels of thyroid, adrenal and gonadal steroid hormones. The relative importance of ethanol consumption and severity of liver disease in the aetiology of these changes and their relationship to clinical abnormalities are unclear. We studied 31 subjects with alcohol-induced liver disease divided into three groups according to the severity of histological features: fatty change, hepatitis and cirrhosis. Circulating concentrations of thyroid, adrenal and gonadal steroid hormones, together with their major binding proteins, were measured in all subjects, and changes related to histology and tests of liver function, as well as clinical endocrine status. A reduction in circulating free tri-iodothyronine (fT3) was seen in subjects with alcoholic hepatitis and cirrhosis, in association with normal or reduced levels of thyrotrophin (TSH). The absence of abnormalities in subjects with fatty change despite similar ethanol intake to the other groups, and correlations between fT3 and liver function tests, suggest that changes in fT3 reflect the severity of underlying liver disease. Similarly, marked increases in circulating cortisol in the hepatitis and cirrhosis groups, and correlations between cortisol and liver function, suggest that changes largely reflect hepatic disease. The absence of clinical features of hypothyroidism or Cushing's syndrome in these groups, despite abnormalities of fT3 and cortisol, suggest an altered tissue sensitivity to hormone effects. In contrast, increases in circulating oestradiol and reductions in testosterone were found in all three groups in males. These findings suggest that both direct effects of ethanol and hepatic dysfunction determine changes in gonadal steroids in males.

Serum thyrotropin responses to thyrotropin-releasing hormone in alcohol-dependent patients with and without depression

Forty-one patients with DSM-III alcohol dependence syndrome were studied, as were 30 patients with major depression and 20 healthy controls. Nineteen of the alcohol-dependent patients had depressive symptoms. All subjects underwent a TRH/TSH stimulation test. Fifty percent of the alcohol-dependent patients without depression had a blunted response, while 52% of patients with depression were similarly blunted. The overall rate of blunting in the non-alcoholic major depressives was 26%. Blunting in the alcoholics was not associated with a personal or family history of affective disorder. Furthermore the blunted response in recently detoxified alcoholics was of no prognostic significance.

Serum prolactin increase induced by ethanol--a dose-dependent effect not related to stress

The effect of moderate ethanol doses (0.5 and 1 g/kg body weight) on serum prolactin (PRL), cortisol, epinephrine and norepinephrine concentrations was measured in a double-blind, placebo-controlled study. Eight healthy male volunteers participated. Blood was with drawn twice before, and 30 min, 60 min, 90 min and 120 min after oral ethanol intake. The higher ethanol dose, but not the lower dose, significantly increased PRL concentrations. Concentrations of cortisol, epinephrine and norepinephrine were not changed by either dose. Thus, the effect of ethanol on PRL appears to be dose-dependent and not stress-related.

Hypothalamic-pituitary and thyroid function in chronic alcoholics with neurological complications

Endocrinological tests were performed in 14 chronic alcoholic men with signs of intellectual impairment and/or peripheral neuropathy. All had been abstinent from alcohol for at least 1 month. Basal serum growth hormone (GH) was consistently increased in only one patient whereas the GH responses to insulin hypoglycemia stimulation was normal in all patients. Thyroid function values (T4, T3, rT3, TSH) were normal in all patients whereas baseline serum prolactin values were significantly increased in alcoholics as compared with a control group. In a combined TRH- and GnRH-stimulation tests, GH-responses were also normal whereas TSH and prolactin responses were blunted or absent in about half of the patients, the responses correlating significantly (p less than 0.01). It is concluded that disturbances in the hypothalamic-pituitary axis may occur in chronic alcoholics with nervous impairment independently of the physical deterioration, which often is associated with chronic alcoholism.

Thyrotropin and prolactin response to thyrotropin-releasing hormone in depressed and nondepressed alcoholic men

Thyrotropin-releasing hormone (TRH) stimulation tests were performed on 81 alcoholic men after at least 3 weeks of abstinence. Subjects were given 500 micrograms of TRH intravenously, and thyroid-stimulating hormone (TSH) and prolactin (PRL) were measured at baseline, and then 15 and 30 min later. Comparisons were made among alcoholics with (n = 27) and without (n = 54) a lifetime history of depression as determined by the Diagnostic Interview Schedule. Nine nondepressed, nonalcoholic subjects served as controls. Alcoholics with or without a depression history did not differ from each other or from control in TSH or PRL response area under the curve. Blunted TSH responses were present in 10 (12%) of the alcoholics and none of the controls when blunting was defined as a delta max TSH less than 5 microU/ml. When blunting was defined as a delta max TSH less than 7 microU/ml, 18 (22%) of the alcoholics and 1 (1%) of the controls were blunted. Conversely, 2 (2.5%) of the alcoholics had a delta max TSH greater than 32 microU/ml. All subjects were clinically euthyroid. Contrary to expectation, depressed subjects were slightly less likely to show blunted responses than nondepressed subjects. No relationship was found between neuroendocrine measurements and several measurements of alcoholism or depression. Some alcoholic subjects show a blunted TSH response to TRH injection, which may be a function primarily of the alcoholism itself. The precise mechanism remains unknown.

Hyperthyroxinaemia in hepatocellular carcinoma: relation to thyroid binding globulin in the clinical and preclinical stages of the disease

Serum thyroxine was significantly higher in 59 patients with hepatocellular carcinoma than in normal subjects, patients with uncomplicated cirrhosis (48), or other primary tumours with or without hepatic metastases (50). Elevated thyroxine levels appeared attributable to high levels of thyroxine binding globulin which showed a positive linear correlation with serum thyroxine in all groups studied. Despite this hyperthyroxinaemia all patients appeared clinically euthyroid and, consistent with this, T3 was elevated in only one patient and the free thyroxine index was normal in all. Amongst a group of 25 cirrhotic patients who were followed-up for between 12 and 72 months, there was a striking dissociation between the TBG values of those destined to develop HCC and those who did not. In the former group TBG rose steadily with time whereas in the latter group levels remained stable, or, more often, fell. The rises in TBG occurred prior to any clinical signs of tumour development and may be one of the earliest serological changes to occur during carcinogenesis in the cirrhotic liver.

Multiple sclerosis and Hashimoto's thyroiditis

A case of multiple sclerosis and Hashimoto's thyroiditis confirmed by cytology is reported. The association of multiple sclerosis with other autoimmune diseases is infrequent but supports the immune hypothesis of the pathogenesis of multiple sclerosis. The authors suggest the inclusion of immunological tests in the screening of all patients diagnosed as having multiple sclerosis.

Thyroid and pituitary hormone responses to TRH in advanced nonalcoholic liver disease

Basal T4, T3, TSH, prolactin and growth hormone levels were determined in several groups: patients with postnecrotic cirrhosis with hepatocellular carcinoma (n = 14); patients with postnecrotic cirrhosis but without hepatocellular carcinoma (n = 26); cholangiolar carcinoma (n = 9); and normal controls age-matched to within 5 yr of the liver disease subjects studied. In addition, TRH stimulation (400 micrograms TRH) was performed; TSH, prolactin and growth hormone responses over a 180-min time interval were evaluated for each subject. The responses observed varied between liver disease groups. The presence or absence of hepatocellular carcinoma was found to determine, at least in part, the type of response observed. Similarly, the presence or absence of hepatic encephalopathy determined, and/or reflected, at least in part, the type of response observed. Finally, for purposes of continuity, basal and TRH-stimulated levels of TSH, prolactin, growth hormone, T4 and T3 are compared in 3 settings of cirrhosis: alcoholic, nonalcoholic postnecrotic cirrhosis, and postnecrotic cirrhosis with hepatocellular carcinoma.

[Thyroid hormones in women with liver cirrhosis]

Basal thyroid hormone levels were measured in 68 women with liver cirrhosis (LC) of different etiology (alcoholic n = 34, posthepatitic B n = 9, PBC n = 5, cryptogenetic n = 18, M. Wilson n = 2). In addition the rise of TSH after 400 micrograms TRH was measured in 23 women with LC and compared with the data obtained from 17 women of a control group. There was no difference of the median T4-concentrations (LC 8.0 micrograms/dl versus 7.2 micrograms/dl) but a significant correlation of T4 to the grade of decompensation of LC. In contrast of T4 there was a marked decrease of T3 in LC-patients (109 ng/dl versus 143 ng/dl) and a rise of reverse T3 (0.21 ng/ml versus 0.13 ng/ml). The decrease of T3 and rise of reverse T3 equally correlated to the severeness of LC. TBG concentrations fell according to the grade of decompensation of LC and T4/TBG-quotient exhibited no difference to the control data (0.51 both). Though basal thyroid hormones and TSH show euthyroidism the significant augmented TSH release after TRH (delta-TSH 7.0 versus 3.2 microU/ml) indicate a status of latent hypothyroidism. In alcoholic cirrhosis the degree of TSH release was much higher than in non alcoholic cirrhosis. Estradiol and estrone levels correlated significantly negatively to T4, T3, estrone negatively to TBG and positively to reverse T3 but not to TSH and TSH release. Otherwise TSH release correlated positively to estradiol. The thyroid status in women with liver cirrhosis does not differ from the thyroid hormone profile found in men with cirrhosis.

The prognostic value of thyroid function tests in predominantly non-alcoholic cirrhotic patients: a prospective investigation

The prognostic value of thyroid function parameters (T3, T4, rT3 and the rT3:T3 ratio) and common liver tests (serum bilirubin, albumin and prothrombin activity) was investigated on hospital admission in 100 consecutive patients with predominantly non-alcoholic liver cirrhosis. Twenty-nine out of 100 patients had a well compensated cirrhosis and their mean values of thyroid tests were similar to those of 40 healthy controls. A low T3 syndrome was found in the remaining 71 decompensated patients. In these thyroid function parameters were correlated with serum bilirubin and prothrombin activity. Moreover mean values of all thyroid and liver tests, except serum albumin, were significantly different between survivors and nonsurvivors at 3 months. To evaluate the best cut-off value which allowed to predict the outcome of patients, the Receiver Operating Characteristics (ROC) curves were generated for each test by plotting the values obtained in survivors at 3 months (true positives) vs nonsurvivors (false positives). By holding the false positive errors within 10%, the highest percentage of true positive results (i.e. patients dead at 3 months) was observed for the rT3:T3 ratio, rT3 and serum bilirubin at a cut-off point of 0.841, 55 ng/dl and 3.5 mg/dl, respectively. According to the above cut-offs the rT3:T3 ratio had the best positive predictive value (74%; 95% confidence limits 60-90%) in comparison to rT3 and bilirubin.

Neuroendocrine alterations in systemic disease

Systemic disorders clearly may exert a significant influence on neuroendocrine function. Disorders that cause significant stress to the body, either physical or psychological, may cause a resetting upward of the HPA axis to provide sufficient cortisol to counteract the stress and to help sustain energy substrate levels. GH levels also increase in many of these situations, again promoting sufficient energy substrate levels. In some circumstances the concomitantly low somatomedin activity may be speculated to be adaptative to prevent the insulin-like agonist activity of these substances as well as to prevent energy expenditure in body growth. However, in other situations such as chronic renal failure and cirrhosis, the decreased somatomedin activity may be primary, causing decreased feedback at the hypothalamic-pituitary level and increased GH levels. The stress-induced rise in PRL may also play a minor role in preserving energy substrate since high levels may promote insulin resistance. In most illnesses the 'euthyroid sick syndrome' develops. Whether such patients are 'euthyroid' or mildly hypothyroid is a matter of controversy. The fact that protein losses are increased during fasting when the lowered T3 levels are returned to normal with exogenous T3 supplementation suggests that these patients are indeed hypothyroid and this hypothyroidism serves to conserve energy substrate by decreasing the metabolic rate. The reproductive axis is often impaired with systemic illness. Again, teleologically this may be viewed as an inactivation of non-essential functions in times of stress. It would appear that the changes that occur with systemic illness, in general, are favourable to the organism in that they promote survival. The detailed neurotransmitter and hypophyseotrophic hormone changes resulting in the alteration in pituitary function remain to be elucidated for the most part.

Hepatic thyroid hormone levels following chronic alcohol consumption: direct experimental evidence in rats against the existence of a hyperthyroid hepatic state

To study the effect of chronic alcohol consumption on hepatic levels of thyroid hormones, female Sprague-Dawley rats (n = 24) were pair-fed nutritionally adequate liquid diets containing either ethanol (36% of total calories) or isocaloric carbohydrates for 21 days. Compared to controls, chronic alcohol consumption failed to result in a significant change of hepatic thyroid hormone levels (thyroxine: 14.7 +/- 1.81 ng per gm of liver wet weight vs. 15.0 +/- 1.59; triiodothyronine: 2.60 +/- 0.16 ng per gm of liver wet weight vs. 2.66 +/- 0.18). Similar results were obtained when the hepatic levels of thyroid hormones were expressed per total liver, per gram of liver protein or per 100 gm of body weight. Moreover, prolonged alcohol ingestion led to a significant reduction of serum total thyroxine by 31.6% (p less than 0.001), free thyroxine by 38.9% (p less than 0.02), total triiodothyronine by 40.2% (p less than 0.001) and free triiodothyronine by 56.1% (p less than 0.001) when compared to their pair-fed controls, whereas thyroid-stimulating hormone levels remained virtually unchanged. These data, therefore, clearly show that chronic alcohol consumption is incapable of creating a hyperthyroid hepatic state in rats, and limit the rationale for antithyroid treatment in patients with alcoholic liver disease.

Thyroid function tests in chronic liver disease: evidence for multiple abnormalities despite clinical euthyroidism

To further evaluate thyroid function in patients with liver disease, we have measured total and free T3 and T4, thyroxine binding globulin, basal and thyrotropin releasing hormone-stimulated thyrotropin and thyroglobulin antibodies in 33 patients with liver cirrhosis, in 22 with chronic hepatitis and in 30 healthy controls. All the patients but one were clinically euthyroid. T3, FT3, T3/thyroxine binding globulin and T4/thyroxine binding globulin ratios and thyrotropin after thyrotropin releasing hormone were significantly reduced, while FT4, thyroxine binding globulin and thyrotropin were significantly increased in liver cirrhosis. In chronic hepatitis group, FT3 and T3/thyroxine binding globulin ratio were significantly lower and thyroxine binding globulin and FT4 were higher than in healthy controls. The between patients comparison revealed a significantly lower T3, FT3, T3/thyroxine binding globulin and T4/thyroxine binding globulin ratios and delta thyrotropin in cirrhotics. Thyroglobulin antibodies were present at high titre only in two patients one of whom having evidence of Hashimoto's thyroiditis with subclinical hypothyroidism. The correlation coefficient between T4/thyroxine binding globulin ratio and FT4 were lower in patients than in controls. Furthermore an abnormal thyrotropin response to thyrotropin releasing hormone was shown in 10 cirrhotics and in four patients with chronic hepatitis. Serum T3 significantly correlated with serum bilirubin, albumin, and prothrombin time in both groups of patients. The present data confirm the existence of several abnormalities of thyroid function tests in patients with chronic liver disease, although showing that euthyroidism is almost always maintained, probably as a result of low-normal FT3 and high-normal FT4. Furthermore, T3 serum levels appear to parallel the severity of liver dysfunction.

Frequency of euthyroid sick syndrome as assessed by free thyroxine index and a direct free thyroxine assay. A limitation of FT4 assays

The frequency of the euthyroid sick syndrome (ESS) was assessed in 3444 hospital patients. For the first 6 months the free thyroxine index (FTI) was used: 3.6% of 1674 patients had ESS compared with 17.3% of 1770 in the second 6 months diagnosed by a direct free thyroxine (FT4) assay ("Amerlex'). The relative frequencies of each type of ESS (low triiodothyronine [T3] only, low T3 plus low FT4 or FTI, and high FT4 or FTI with normal or low T3) and the frequencies of hypothyroidism (high TSH) and hyperthyroidism (high FTI/FT4 and T3) were similar in both periods. In the FT4 period requests for T3 assays increased by 300%. Measurements of both FT4 and FTI in 46 patients with ESS confirmed that ESS is diagnosed more frequently with the FT4 assay: the distribution of normal and abnormal T3 and reverse T3 levels were similar in FT4 ESS and FTIESS. FT4 is labile in illness and thus direct FT4 measurements also fluctuate, not necessarily reflecting thyroid status.

Changes in pituitary secretion after administration of branched-chain amino acids to patients with hepatic cirrhosis

Infusion of a mixture of branched-chain 1-amino acids (BCAA; isoleucine, leucine, and valine) in six male patients suffering from hepatic cirrhosis led to an increase in serum GH, while serum PRL was not affected. In the same patients arginine infusion stimulated GH and PRL release. These findings demonstrate that hypothalamo-pituitary responsiveness to amino acid stimulation is preserved in cirrhosis and that administration of these amino acids has some endocrine effect.

Free thyroxine by solid phase radioimmunoassay: improvement in the laboratory diagnosis of thyroid status in severely ill patients

During severe systemic illness total thyroid hormone levels are often low, and measurement of total hormones often does not differentiate between euthyroid and hypothyroid patients. Therefore, we examined serum free thyroxine levels by radioimmunoassay (antibody-coated tubes, Clinical Assays) as an alternative diagnostic test in three groups of severely ill patients with subnormal triiodothyronine. Free thyroxine estimates agreed with the clinical impression and TSH in 91% of cases in group 1 (47 patients with no history or clinical evidence of thyroid disorder), in 96% of cases in group 2 (24 euthyroid patients with a previous history of thyroid disease, including some on thyroid replacement) and 90% of cases in group 3 (10 hypothyroid patients). By contrast, the free thyroxine index did so in only 53% (group 1), 46% (group 2) or 100% (group 3). Sequential studies showed little change in free thyroxine and TSH levels in euthyroid patients during illness and recovery, and a good negative correlation between free thyroxine and TSH in hypothyroid patients. Free thyroxine measurements (and TSH) discriminate between euthyroid and hypothyroid sick patients better than other thyroid function tests including the free thyroxine index, and can be employed routinely: a distinct advantage over free thyroxine measured by equilibrium dialysis.

Prevalence of abnormal thyroid function test results in patients with acute medical illnesses

We measured serum total and free thyroxine (T4) and triiodothyronine (T3) concentrations, free T4 and T3 indexes, thyroid-stimulating hormone (TSH), thyroxine-binding globulin (TBG) and thyroxine-binding prealbumin (TBPA) concentrations in 98 patients hospitalized for acute medical illnesses. The free thyroxine index (FT4I) or TSH level was abnormal in 16 percent, but only 3 percent had thyroid disease. Serum fre T4 measurements by equilibrium dialysis were abnormal in 25 percent, but no additional patients who initially had abnormal concentrations of serum free T4 were subsequently proved to have thyroid disease. Patients with supranormal serum free T4 concentrations (21 percent) ahd higher serum T4, lower serum T3, and higher serum reverse T3 (rT3) concentrations than other patients, but the measured changes in serum T4, TBG and TBPA levels could only partly account for the magnitude of the free T4 elevation. In these acutely ill patients, an accurate diagnosis of thyroid disease could be achieved by determination of FT4I and TSH level and a history of medication usage. We conclude that other tests are rarely necessary for this purpose in a patient population such as this.

Alterations in circulating thyroid hormones and thyroxine binding globulin in chronic alcoholism

The present study concerns eighteen chronic alcoholics with minimal liver damage. A significant reduction in total serum T4 with an accompanying drop in circulating TBG was observed in these otherwise euthyroid patients. During alcohol withdrawal, we observed a rapid increase in T4 and TBG into the normal range. We suggest that the fall in the level of circulating thyroxine-binding globulin is related to a defect in its synthesis or secretion by the liver due to ethanol consumption. Caution is recommended in the interpretation of thyroid function tests in chronic alcoholics.

Relations between serum levels of TSH, TBG, T4, T3, rT3 and various histologically classified chronic liver diseases

Serum levels of TSH, thyroxine-binding globulin (TBG), T4, T3 and reverse T3 (rT3) were measured in 36 patients with fatty liver disease, 11 patients wih chronic persistent hepatitis, 17 patients with chronic active hepatitis, and 29 patients with liver cirrhosis. TBG was significantly above normal levels in both groups of chronic hepatitis, the slight concomitant T4 and T3 increase was significant only for T4 in chronic persistent hepatitis. A significant decrease in T4 and T3 concentration was found in fatty liver disease and in hepatic cirrhosis. A shift in T4 conversion to rT3 could exclusively be demonstrated for the group of hepatic cirrhosis, reflected by a significant increase in rT3. As our findings indicate normal TSH levels and a lack of clinical signs of hypothyroidism in chronic liver disease, the possibility of diverse regulating changes must be considered.

Abnormal thyroid function tests in devere non-thyroidal illness: diagnostic and pathophysiologic aspects

In vitro thyroid function tests were studied in twenty-three patients with serious non-thyroidal illness. All had reduced protein binding of serum thyroxine (T4) and serum triiodothyronine (T3) as reflected in increased T4 and T3 uptake tests. The mean T4-binding prealbumin (TBPA) capacity and concentration were about one third the normal levels, whereas the decrease in R4-binding globulin (TBG) was much smaller. Increased serum free fatty acids and reverse T3 were frequently observed, but in vitro displacement of thyroid hormones from their binding sites was achieved only with much high concentrations of these compounds. Other still unrecognized substances significantly inhibiting binding of thyroid hormones might, however, occur in sera of severely ill patients. Evidence in favour of this possibility was the disproportionately high serum T4 by TBG-binding assay relative to T4 by radioimmunoassay. In most of the patients the dual-stage free T4 was elevated, whereas the single-stage free T4 index (CT4I) was within the reference interval. However, neither of these indices reflected the moderately increased dialysable free T4 concentration very accurately. The free T3 index was depressed in most of the patients, whereas the dialysable free T3 concentration was not affected. For practical purposes the combination of normal serum T4 and CT4I in a severely ill patient indicates absence of an associated thyrometabolic disorders.