Primary Thyroid Disease Research Articles

Vasovagal reflex emergency caused by Riedel's thyroiditis: A case report and review of the literature

Riedel's thyroiditis is a rare type of chronic thyroiditis, associated with fibroinflammatory process and invasion into surrounding tissues, leading to compressive symptoms. A 45-year-old man had a left thyroid mass, presenting with hypotension and bradycardia many times. He was diagnosed with vasovagal reflex caused by cervical vessel compression due to a thyroid lesion. We performed the emergency operation, and most of the left thyroid was removed to relieve the compression on cervical vessels. The result of pathology proved to be Riedel's thyroiditis. The vasovagal reflex did not occur any more during the 28-month follow up, except on the 3(rd) day after the surgery. Six months after the thyroidectomy, the patient was found to have retroperitoneal fibrosis, diagnosed by biopsy during a laparotomy for biliary disease. Riedel's thyroiditis can lead to a vasovagal episode and might not be a primary thyroid disease but rather a manifestation of the systemic disorder, multifocal fibrosclerosis.

Differentiating Nonrestorative Sleep from Nocturnal Insomnia Symptoms: Demographic, Clinical, Inflammatory, and Functional Correlates

Recent studies have suggested that nonrestorative sleep (NRS) symptoms may be distinct from nocturnal insomnia symptoms (NIS). However, there is limited information on the demographic, medical, and biologic correlates of NRS independent from NIS in the general population. This report presents the sociodemographic correlates, patterns of comorbidity with other sleep and physical disorders, C-reactive protein (CRP) levels, and general productivity associated with NIS and NRS in a nationally representative sample of US adults. National Health and Nutrition Examination Survey (NHANES). The 2005-2008 surveys of the general population in the United States. There were 10,908 individuals (20 years or older). N/A. Respondents were classified by the presence or absence of NIS and NRS. Compared with those without insomnia symptoms, respondents with NIS were older and had lower family income and educational levels than those with NRS. In addition, there was a significant association between NIS and cardiovascular disease, whereas NRS was associated with other primary sleep disorders (including habitual snoring, sleep apnea, and restless legs syndrome), respiratory diseases (emphysema and chronic bronchitis), thyroid disease, and cancer as well as increased CRP levels. In addition, the study participants with NRS only reported poorer scores on the Functional Outcomes of Sleep Questionnaire (FOSQ) than those without insomnia symptoms or those with NIS only. These findings suggest that there are substantial differences between NIS and NRS in terms of sociodemographic factors, comorbidity with other sleep and physical disorders, increased CRP level, and functional impairment. An inflammatory response might play a unique role in the pathogenesis of NRS.

The thyroid gland: an unusual location for burkitt’s lymphoma

Primary thyroid gland lymphomas are extremely uncommon, forming about 5% of all thyroid neoplasms and the lymphomas constituting primary thyroid lymphomas are usually marginal zone B-cell lymphoma and diffuse large B-cell lymphoma. Burkitt's lymphoma affecting the thyroid gland has been rarely described. In this report, we document a rare instance of a thyroid Burkitt's lymphoma affecting a 46-year-old Filipino lady. She presented with a right thyroid nodule of 4 month's duration for which she sought medical attention. Fine needle aspiration (FNA) of the nodule revealed an atypical proliferation of lymphoid cells suspicious of a lymphoma, and subsequent excision of the thyroid gland disclosed typical features of Burkitt's lymphoma, the tumour being composed of medium sized CD20+ CD10+ bcl-2 lymphoid cells with a Ki-67 proliferation index of 100%. Flourescent <i>in situ</i> hybridisation for c-myc amplification, IgH-myc fusion, IgH-bcl-2 fusion and bcl-6 re-arrangement confirmed a diagnosis of Burkitt's lymphoma. As the patient did not have any clinical evidence of disease elsewhere, a primary thyroid disease was presumed. The pathology including cytological features of thyroid Burkitt's lymphoma is presented. The dilemmas associated with the diagnosis of Burkitt's lymphoma are discussed.

Increased primary autoimmune thyroid diseases and thyroid antibodies in sarcoidosis: evidence for an under-recognised extrathoracic involvement in sarcoidosis?

Sarcoidosis has been associated with thyroid diseases. However, until today no definite conclusions have been drawn. We aimed to assess the frequency of thyroid disorders and the levels of thyroid hormones and thyroid antibodies in 68 sarcoidosis patients and 75 controls. Additionally, we performed ultrasonography and fine-needle aspiration. In this prospective case control study conducted in the University Hospital of Larissa, Greece, overt thyroid disease was present in 29.4% of patients and 16.1% of patients presented clinical autoimmune thyroid disease. Sarcoidosis patients had a significantly higher frequency of serological autoimmunity. Female patients had significantly increased frequency of positive TSH receptor antibodies (TRAbs) and antithyroid peroxidase antibodies (TPOAbs) when compared to gender-matched controls (40% vs 0%, p<0.001, and 28.8% vs 11.86%, p=0.029, respectively). The hypoechoic pattern of the thyroid was more frequent in female patients vs controls (p<0.001). Male patients had a higher frequency of TRAbs and hypoechoic pattern of the thyroid gland (43.4% vs 0%, p=0.002, and 39.1% vs 6.25%, p=0.021, respectively). Indices of thyroid autoimmune disease were significantly more frequent in sarcoidosis patients vs gender-matched controls. Increased TPOAbs were significantly associated with clinical autoimmune disease in sarcoidosis. Overall, the findings derived from this study suggest that thyroid disorders are frequent in sarcoidosis. This association may potentially be the result of increased thyroid antibodies.

The Evaluation of Thyroid Diseases in Patients with Pemphigus Vulgaris

Background. Thyroid disorders may affect all of the organ systems of the body and they are also highly associated with a wide variety of skin disorders. The aim of this study was to investigate the prevalence of thyroid function abnormalities and thyroid autoimmunity in patients with pemphigus vulgaris (PV) and to determine the association between thyroid disorders and clinical involvement and systemic corticosteroid treatment in patients with PV. Methods. The study consisted of eighty patients with PV and eighty healthy individuals. Thyroid functions (fT3, fT4, and TSH) and thyroid autoimmunity (anti-thyroid peroxidase (anti-TPO), and anti-thyroglobulin (anti-Tg) antibodies) were investigated in both groups. Primary thyroid disease (PTD) was diagnosed with one or more of the following diagnostic criteria: (i) positive antithyroid antibodies, (ii) primary thyroid function abnormalities. Results. Significant changes in the serum thyroid profile were found in 16% (13/80) of the PV group and 5% (4/80) of the control group. Positive titers of antithyroid antibodies (anti-TPO and anti-Tg) were observed in 7 patients (9%) with PV and one in the control group (1,2%). Hashimoto thyroiditis was diagnosed in 9% of PV patients and it was found to be more prevalent in the mucosal form of PV. PTD was found in 13 of (%16) PV patients which was significantly high compared to controls. PTD was not found to be associated with systemic corticosteroid use. Free T3 levels were significantly lower in PV group compared to the control group and free T4 levels were significantly higher in PV group compared to the controls. Conclusions. PV may exist together with autoimmune thyroid diseases especially Hashimoto thyroiditis and primer thyroid diseases. Laboratory work-up for thyroid function tests and thyroid autoantibodies should be performed to determine underlying thyroid diseases in patients with PV.

Diagnosis and treatment of hypothyroidism in TSH deficiency compared to primary thyroid disease: pituitary patients are at risk of under-replacement with levothyroxine

Achieving optimal thyroid hormone replacement is more difficult in TSH deficiency compared to primary hypothyroidism because of the inability to be guided by serum TSH levels. A combination of clinical symptoms and free thyroxine levels (fT4) are typically used to make a diagnosis and monitor replacement. We investigated the diagnosis of TSH deficiency in patients with pituitary disease and the adequacy of levothyroxine replacement compared with primary thyroid disease. Using our department's clinical information system, we identified all patients with a diagnosis of any type of pituitary tumour who had been seen in clinic over a 2-year period. We divided the patients into those at high risk and low risk of TSH deficiency based on the presence of macroadenoma and/or intervention by surgery or radiotherapy. We compared fT4 values in these patients with values in patients with primary thyroid disease in our thyrotoxicosis shared-care scheme (TSC) and hypothyroid register within the same timescale, assessing only those samples considered euthyroid in which TSH was in the normal range. A database query identified 525 patients with a pituitary tumour of whom 344 were considered at high risk of TSH deficiency. A free T4 (fT4) value was found for 514 patients (97·9%). TSC and thyroid register databases revealed fT4 values for comparison with simultaneous normal TSH in patients on no treatment (n = 3777 samples) or on levothyroxine alone (n = 11,805). fT4 levels overall were lower in pituitary patients than in equivalent controls. Of the high risk group not taking levothyroxine 17% had a free T4 ≤ 11 pmol/l compared to only 8·4% of untreated controls. Furthermore, 38·9% of patients on levothyroxine had a free T4 ≤ 13 pmol/l compared to 9·5% of controls on levothyroxine with previous thyrotoxicosis and 13·4% of controls with primary hypothyroidism. Median fT4 in controls on levothyroxine was 16 pmol/l and 20-80th centile range was 14-19 pmol/l. Levothyroxine doses were generally under-replaced in pituitary patients compared to primary thyroid disease and the data imply that some untreated patients were actually TSH deficient. The distribution of fT4 in patients with primary thyroid disease on levothyroxine may guide optimum replacement levels in pituitary disease.

Stereotactic radiosurgery in the management of brain metastases from primary thyroid cancers

Patients with metastatic well-differentiated thyroid cancer have a generally favorable long-term outcome although multi-organ involvement is a known marker of poor prognosis. Brain metastases are rare, occurring in less than 1% of patients with thyroid cancer. Few patients have been managed with stereotactic radiosurgery (SRS). A retrospective database of 5,067 patients treated for brain metastases between 1985 and 2007 was generated from 11 institutions. Thyroid cancer patients were identified in this database and, when possible, additional information was obtained from further chart review. Patients were excluded if they had incomplete treatment or follow-up information. Two validated prognostic indices, Graded prognostic Assessment (GPA) and Recursive Partitioning Analysis (RPA), were calculated for each patient. The overall survival times were calculated by the Kaplan-Meier method. Twenty-three thyroid cancer patients were identified (51% male, 48% female). Median age was 63 years (range 20-81). Pathology of the primary thyroid disease was available for twelve patients; the majority were diagnosed with differentiated thyroid cancer (n = 9 papillary, n = 2 Hürthle cell; 92%) and one had medullary subtype (8%). Median time from diagnosis of primary disease to brain metastasis was 41.8 months (range 0-516). Fifteen (65%) patients underwent SRS as part of their initial treatment with a median number of lesions treated of 1.5 (range 1-9). The median follow-up time for living patients was 35.2 months. Overall median survival time was 20.8 months (40% alive at last follow-up) and 37.4 months for SRS-treated patients (P = NS). A poor Karnofsky performance status was predictive of worse outcome (P = 0.001). GPA and RPA did not provide additional prognostic information. In conclusion, patients treated with SRS for brain metastases from primary thyroid cancer have a favorable prognosis with an expected median survival greater than 3 years. It is unclear as to whether current prognostic indices are relevant to this patient population.

Conversion disorder in women with the FMR1 premutation

Women with fragile X mental retardation (FMR1) gene premutations (55-200 CGG repeats) were until recently believed to be unaffected. It is now known that up to 8% of older female FMR1 premutation carriers develop fragile X-associated tremor/ataxia syndrome (FXTAS). Female carriers may also develop primary ovarian insufficiency, thyroid disease, hypertension, seizures, peripheral neuropathy, and fibromyalgia. We present a 60-year-old woman with FMR1 premutation who had depression, anxiety, and conversion disorder with seizures. The FMR1 premutation with its associated mRNA toxicity is postulated as an underlying neurobiological mechanism of conversion symptoms, through functional and structural neural dysconnectivity.

Thyroid Hormone and Coronary Artery Disease: From Clinical Correlations to Prognostic Implications

Overt thyroid dysfunction, hypothyroidism in particular, may lead to coronary artery disease (CAD). Whether more subtle anomalies of thyroid hormone metabolism influence the progression of CAD remains a matter of speculation. The occurrence of CAD and long-term prognosis in patients without a history of either primary thyroid disease, myocardial infarction, or chronic heart failure is related to serum levels of biologically active free triiodothyronine (fT3). The cohort consisted of 1047 clinically and biochemically euthyroid patients (median age 65.6 y and 69% male) who underwent coronary angiography in our institute for suspected CAD. Lower fT3 levels were predictive of both single-vessel (p = 0.012) and multivessel (p = 0.009) CAD. Through a multivariate logistic regression analysis, fT3 was still linked to the presence of CAD (hazard ratio [HR]: 0.48, 95% confidence interval [CI]: 0.34-0.68, p < 0.001). After a mean follow-up of 31 months, the survival rate was 95% and total mortality (log-rank 6.75, p = 0.009), as well as cardiac mortality (log-rank 8.26, p = 0.004), was greater among patients with low T3 (fT3 < 2.10 pg/mL) syndrome. At subsequent multivariate Cox regression analysis, the association between low T3 syndrome and survival was maintained (total mortality HR: 1.80, 95% CI: 1.05-3.10, p = 0.034; cardiac mortality HR: 2.58, 95% CI: 1.13-5.93, p = 0.025). In this selected population, fT3 levels were inversely correlated to the presence of CAD and low T3 syndrome conferred an adverse prognosis, even after adjusting for traditional coronary risk factors.

The Thyroid‐Brain Interaction in Thyroid Disorders and Mood Disorders

Thyroid hormones play a critical role in the metabolic activity of the adult brain, and neuropsychiatric manifestations of thyroid disease have long been recognised. However, it is only recently that methodology such as functional neuroimaging has been available to facilitate investigation of thyroid hormone metabolism. Although the role of thyroid hormones in the adult brain is not yet specified, it is clear that without optimal thyroid function, mood disturbance, cognitive impairment and other psychiatric symptoms can emerge. Additionally, laboratory measurements of peripheral thyroid function may not adequately characterise central thyroid metabolism. Here, we review the relationship between thyroid hormone and neuropsychiatric symptoms in patients with primary thyroid disease and primary mood disorders.

Risk of Vocal Palsy After Thyroidectomy with Identification of the Recurrent Laryngeal Nerve

The purpose of this study was to assess the risk of vocal palsy after thyroidectomy with identification of recurrent laryngeal nerve (RLN) during surgery. In all, 521 patients treated by the same surgeon were enrolled in this study. Temporary and permanent vocal palsy rates were analyzed for patient groups classified according to surgery for primary benign thyroid disease, thyroid cancer, Graves' disease, and reoperation. Measurement of the vocal palsy rate was based on the number of nerves at risk. Twenty-six intentionally sacrificed RLNs were excluded from analysis. Forty patients developed postoperative unilateral vocal palsy. Complete recovery of vocal palsy was documented for 35 of the 37 patients (94.6%) whose RLN integrity had been ensured intraoperatively. Recovery from temporary vocal palsy ranged from 3 days to 4 months (mean, 30.7 days). The overall incidences of temporary and permanent vocal palsy were 5.1% and 0.9%, respectively. The rates of temporary/permanent vocal palsy in groups classified according to underlying disease were 4.0%/0.2% for benign thyroid disease, 2.0%/0.7% for thyroid cancer, 12.0%/1.1% for Graves' disease, and 10.8%/8.1% for reoperation. Surgery for thyroid cancer, Graves' disease, and recurrent goiter were associated with significantly higher vocal palsy rates. Most patients without documented nerve damage during the operation recovered from postoperative vocal palsy. Total lobectomy with routine RLN identification is recommended as a basic procedure in thyroid surgery.

Thyroid, brain and mood modulation in affective disorder: insights from molecular research and functional brain imaging.

The efficacy resulting from adjunctive use of supraphysiological doses of levothyroxine has emerged as a promising approach to therapy and prophylaxis for refractory mood disorders. Most patients with mood disorders who receive treatment with supraphysiological doses of levothyroxine have normal peripheral thyroid hormone levels, and also respond differently to the hormone and tolerate it better than healthy individuals and patients with primary thyroid diseases. Progress in molecular and functional brain imaging techniques has provided a new understanding of these phenomena, illuminating the relationship between thyroid function, mood modulation and behavior. Thyroid hormones are widely distributed in the brain and have a multitude of effects on the central nervous system. Notably many of the limbic system structures where thyroid hormone receptors are prevalent have been implicated in the pathogenesis of mood disorders. The influence of the thyroid system on neurotransmitters (particularly serotonin and norepinephrine), which putatively play a major role in the regulation of mood and behavior, may contribute to the mechanisms of mood modulation. Recent functional brain imaging studies using positron emission tomography (PET) with [ (18)F]-fluorodeoxyglucose demonstrated that thyroid hormone treatment with levothyroxine affects regional brain metabolism in patients with hypothyroidism and bipolar disorder. Theses studies confirm that thyroid hormones are active in modulating metabolic function in the mature adult brain, and provide intriging neuroanatomic clues that may guide future research.

Primary thyroid disorders in endogenous Cushing's syndrome.

To study the prevalence of primary thyroid disorders in patients who underwent endogenous hypercortisolism. Retrospective evaluation of 59 patients with Cushing's syndrome (CS) who had, at least, a record of thyroid palpation by expert endocrinologists and basal measurements of TSH by second generation assays. When available, tri-iodothyronine and thyroxine serum levels, TRH-TSH tests and anti-thyroid antibodies were also analyzed. There were two age- and gender-matched control groups. The 'goiter control group' comprised 118 healthy subjects who underwent thyroid palpation. The 'antibody control group' was composed of 40 individuals who attended the blood bank of our hospital. Antibodies against thyroperoxidase and measurements of TSH were analyzed in their blood samples. Available files of 83 CS patients admitted to our endocrine unit from 1985 to 1998 were examined. Fifty-nine patients (52 women and 7 men) with a mean age of 36.2 years (range 14-61 years) met the above requirements. Diagnosis of hypercortisolism had been established by a standard 1-mg overnight dexamethasone suppression test and urinary free cortisol (UFC). Etiological diagnosis involved dynamic testing, measurements of ACTH levels and imaging techniques. After treatment, all but one of the patients were cured or controlled of their hypercortisolism. This was established by the finding of subnormal serum cortisol concentrations and/or subnormal 24-h UFC levels. Primary thyroid disorders were defined by the presence of one or more of the following diagnostic criteria: (i) goiter, (ii) positive anti-thyroid antibodies and/or (iii) primary thyroid function abnormalities. Eighteen (30.5%) patients had goiter (diffuse in 78% and nodular in 22%), 14 (23.7%) had primary subclinical hypothyroidism and 5 (8.4%) had hyperthyroidism. In 41 patients evaluated for antithyroid antibodies, it was found that 23 (56.1%) had positive titers. In a group of patients in which thyroid autoantibodies were measured both before and after resolution of hypercortisolism, prevalences of positive titers were 26.7% and 86.7% respectively (P=0.001). The overall frequency of primary thyroid abnormalities in our patients with Cushing's syndrome was 55.9%. Patients with endogenous Cushing's syndrome exhibit a remarkably high prevalence of primary thyroid disease. Resolution of hypercortisolism seems to trigger the development of autoimmune thyroid disorders in presumably predisposed subjects.

Thyroid and sympathetic influences on plasma leptin in hypothyroidism and hyperthyroidism

To determine the dependence of plasma leptin concentrations upon circulating noradrenaline (NA) and thyroid hormones (TH) in humans. Cross-sectional study in 40 newly diagnosed untreated patients with primary thyroid disease, and 69 lean and obese euthyroid control subjects. Plasma leptin, NA, free T3 (fT3) and TSH in the fasting state. Anthropometry and % body fat (electrical bioimpedance). Leptin levels were highest in 37 obese euthyroid and 22 hypothyroid (median [interquartiles]31.5 [19.0- 48.0], 19.2 [11.5-31.5] ng ml(-1)), and lowest in 32 lean euthyroid and 18 hyperthyroid subjects (6.6 [3.9-14.4], 8.9 [5.5-11.1]; ANOVA, P< 0.0001). Plasma NA was similar in all groups (P= n.s.). In obese controls, TSH correlated with % body fat and leptin (r= 0.67, r= 0.61; P< 0.001). Treatment of hypothyroidism (n= 10) with T4 reduced leptin from 20.8 [11.8-31.6] to 12.9[4.6-21.2] (P= 0.005) with no change in BMI. Thyroid status modifies leptin secretion independently of adiposity and NA. The data suggest leptin-thyroid interactions at hypothalamic and adipocyte level.

Coexistence of primary hyperparathyroidism and thyroid disease.

Primary hyperparathyroidism (HPT) and thyroid disease are both relatively common diseases, which can coexist in the same patient. However, mere coincidence does not seem to be a satisfactory explanation for this association. Some factors like prior exposure to radiation may play a role in the association. The aim of this study was to determine the frequency of thyroid disease associated with HPT in 54 consecutive patients who underwent parathyroidectomy in our center from January 1990 to December 1997. Twenty-eight (52%) patients had thyroid disease associated to HPT. The patients had a mean age of 61+/-13 yr; they were predominantly postmenopausal women. Thyroid disease was detected preoperatively in 20 (71%) patients and during the surgical procedure in 8 (29%). Two patients had previous radiation exposure; one of them with papillary carcinoma of the thyroid. Two patients had hypothyroidism. UItrasonography was performed in the majority of patients in their preoperative evaluation. A multinodular goiter was seen to be the most frequent finding (76%). In addition to parathyroidectomy, 23 (82%) patients were also thyroidectomized. In conclusion, patients with HPT showed a high prevalence of thyroid disease, especially in postmenopausal women. Unsuspected thyroid lesions were found with sufficient frequency to warrant careful preoperative and intraoperative evaluation of both glands, in order to obviate reoperation. In experienced hands, combined surgery can be safely performed. Cervical ultrasonography is useful in the preoperative detection of nodular thyroid disease in these patients.

Depression and Endocrine Disorders: Focus on the Thyroid and Adrenal System

Of the various hypothalamic-pituitary-end organ axes, the thyroid and adrenal systems have been implicated most often in affective disorders. Patients with primary thyroid disease have high rates of depression, and patients with Addison's disease or Cushing's syndrome have relatively high rates of affective and anxiety symptoms. However, the major support for these endocrine axes in the pathophysiology of mood disorders comes from studies in which alterations in components of the hypothalamic-pituitary-thyroid (HPT) and the hypothalamic-pituitary-adrenal (HPA) axes have been documented in patients with primary depression. Concerning the HPT axis, depressed patients have been reported to have: (a) alterations in thyroid-stimulating hormone response to thyrotropin-releasing hormone (TRH); (b) an abnormally high rate of antithyroid antibodies; and (c) elevated cerebrospinal fluid (CSF) TRH concentrations. Moreover, tri-iodothyronine has been shown conclusively to augment the efficacy of various antidepressants. Concerning the HPA axis, depressed patients have been reported to exhibit: (a) adrenocorticoid hypersecretion; (b) enlarged pituitary and adrenal gland size; and (c) elevated CSF corticotropin-releasing factor concentrations. All of the HPA axis alterations in depression studied thus far are state-dependent, whereas the HPT axis alterations may be partially trait and partially state markers.

AN IMMUNOCHEMILUMINOMETRIC ASSAY FOR SERUM FREE THYROXINE

An immunochemiluminometric assay has been developed for the measurement of free T4 concentrations in serum. The assay uses chemiluminescent acridinium ester labelled monoclonal antibodies which react with free T4 in the sample. A T4-rabbit immunoglobulin G conjugate competes for antibody binding sites, immune-complexes containing this being isolated using an anti-immunoglobulin G antibody coupled to paramagnetic particles. Associated chemiluminescence intensity is thus dependent on the free T4 concentration. The assay distinguishes patients with primary thyroid disease from euthyroid subjects and is unaffected by abnormal binding proteins which compromise the diagnostic accuracy of radiolabelled analogue immunoassays. the test yields results which accurately reflect the clinical thyroid status of euthyroid patients with a variety of acute and chronic non-thyroid illnesses. This is again in marked contrast to the aberrant results seen using certain radiolabelled analogue procedures.

Familial dysalbuminemic hyperthyroxinemia associated with primary thyroid disease

This study describes a family with intrinsic thyroid disease in addition to familial dysalbuminemic hyperthyroxinemia, a syndrome associated with euthyroidism and increased binding of thyroxine to serum albumin. The simultaneous occurrence of thyroid disease and elevated serum thyroxine concentrations due to familial dysalbuminemic hyperthyroxinemia may confound the diagnosis of the two concurrent disorders and the subsequent therapy of the thyroid disease.

Carcinoma Metastatic to the Thyroid: Prevalence and Diagnosis by Fine-Needle Aspiration Cytology

Although metastatic involvement of the thyroid is not commonly considered in the differential diagnosis of a patient with a thyroid mass, such involvement may be more frequent than has been previously appreciated. To evaluate the prevalence of this disorder, all patients with thyroid nodules referred in a 12-month period underwent fine-needle aspiration, regardless of history or scan results. Seventy patients were studied, six of whom had a previous history of malignant disease. Two of the latter had coincidental thyroid disease, but four (5.7% of the total series) had carcinoma metastatic to the thyroid gland. Two of these patients had had no evidence of malignancy for years prior to the appearance of the thyroid metastases. In one case, the metastasis was a functioning nodule. Fine-needle aspiration cytology provided prompt and accurate diagnosis in all patients. We conclude that (1) metastatic carcinoma to the thyroid is not rare, (2) its presentation may be confused with primary thyroid disease, and (3) fine-needle aspiration cytology is the procedure of choice in such cases, and should be done early in the evaluation of all patients with thyroid nodules, regardless of the presumed etiology or function by scan.

Patients with severe nonthyroidal illness and serum thyrotropin concentrations in the hypothyroid range

This report compares three patients with severe nonthyroidal illness and serum thyrotropin concentrations in the range normally associated with hypothyroidism (greater than 20 μU/ml) and a severely ill patient with primary hypothyroidism. No evidence for primary thyroid disease was found among the severely ill patients. Serial studies showed that, in general, the elevated thyrotropin level was associated with an increase in serum thyroxine concentration. Serum free thyroxine concentration, triiodothyronine-to-thyroxine ratio, and thyrotropin response to thyrotropin-releasing hormone were in the range reported in severe nonthyroidal illness and clearly different from that in the severely ill patient with primary hypothyroidism. Serum thyrotropin concentration in severe nonthyroidal illness may be elevated in the range previously thought to be diagnostic of primary hypothyroidism.