Cardiovascular risk factors in primary hyperparathyroidism

BACKGROUND AND AIMS

Severe primary hyperparathyroidism (PHP) has been associated with increased cardiovascular morbidity. Such an association in mild PHP is not known. We conducted a cross-sectional study to assess the correlation between mild and traditional PHP and emergent cardiovascular risk factors.

SUBJECTS AND METHODS

A total of 139 patients with PHP (72 with severe PHP and indications for parathyroidectomy, 67 with mild PHP and no indications for surgery) and 111 control subjects, of similar age and body weight, were enrolled in this study. Participants had measurement of fasting blood levels of calcium, PTH, insulin, glucose, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglycerides, interleukin-6, and C-reactive protein. Body mass index (BMI), waist and hip circumferences, blood pressure, homeostasis model assessment 2-insulin resistance index (IR) and the presence of metabolic syndrome (MS) were evaluated.

RESULTS

Severe PHP patients had significantly higher rates of MS (37.5%), IR (38.9 %) vs mild PHP (34.3 and 23.9%, respectively) and controls (14.4 and 14.4%, respectively). Multivariate logistic-regression model, adjusted for age and BMI, and for age and waist size, revealed that severe PHP had significantly higher likelihood of cardiovascular risks [odds ratio (OR) 3.5, 95% confidence interval (CI) 1.5-8.125, p=0.004 for MS, and OR 3.7, 95% CI 1.64-8.29, p=0.002 for IR]. Serum calcium significantly predicted the presence of MS (OR 1.875, 95% CI 1.259-2.793, p=0.002) and IR (OR 2.043, 95% CI 1.365-3.057, p=0.002).

CONCLUSIONS

Greater probability of MS and insulin resistance was observed in patients with severe PHP. Serum calcium is a predictor of these cardiovascular risk factors.

Concurrent nonfunctioning parathyroid carcinoma and parathyroid adenoma

Parathyroid carcinoma is a rare etiology of primary hyperparathyroidism characterized by severe clinical symptoms of hypercalcemia and markedly elevated serum parathormone levels. Nonfunctioning parathyroid carcinoma is an inactive form of the disease. There are less than 30 reports of nonfunctioning parathyroid carcinoma in the English literature and the association with parathyroid adenoma has not been described. This report describes a patient with concurrent nonfunctioning parathyroid carcinoma and a functioning parathyroid adenoma.

Prevalence and risk factors for asymptomatic bacteriuria in women with Type 2 diabetes mellitus

AIMS

Asymptomatic bacteriuria (ASB) has been considered as a complication in diabetic women. The reported data on the prevalence and various risk factors for ASB appear to be conflicting. Consequently, we investigated the prevalence and major risk factors of ASB in women with Type 2 diabetes mellitus.

METHODS

A total of 411 non-pregnant women (aged 59.6 +/- 10.8 years) with Type 2 diabetes, and 160 women without diabetes (aged 53.3 +/- 15.1 years) assigned as controls, attending an outpatient endocrine clinic in a university-affiliated teaching hospital, were included. All participating women were interviewed and screened for the presence of ASB. In all participants, fasting blood glucose, HbA(1c) and renal function were measured. Complications of diabetes were also assessed.

RESULTS

Of the 411 diabetic women, 25 (6.1%) had ASB, compared with four of 160 (2.5%) in control women (P = 0.07). Independent risk factors for the presence of ASB were albuminuria > 150 mg/24 h [odds ratio (OR) 4.96 (95% CI 1.64-15.0, P = 0.005)] and serum creatinine [OR 3.5 (95% CI 1.4-8.8, P = 0.008)]. No significant association was evident with age, BMI, duration of disease, glycaemic control assessed by HbA(1c) or chronic complications of diabetes, namely macrovascular disease, neuropathy and retinopathy.

CONCLUSIONS

Women with Type 2 diabetes are not at higher risk of developing ASB than non-diabetic women. Independent and significant risk factors for ASB are macroalbuminuria and serum creatinine. The low prevalence of ASB found in this study may be as a result of the ethnic origin of these women and the circumcised state of their partners.

Urinary 6-sulfatoxymelatonin excretion in hyperandrogenic women: the effect of cyproterone acetate-ethinyl estradiol treatment

Evidence for a relationship between melatonin and the reproductive hormones in humans is based on observations of abnormal melatonin secretion in clinical disorders of the pituitary-gonadal axis. The aim of this study was to investigate melatonin production in hyperandrogenic women before and during treatment with cyproterone acetate and ethinyl estradiol (Diane 35). Twelve women with polycystic ovary syndrome (PCOS), 10 women with idiopathic hirsutism (IH), and 10 women with late onset adrenal hyperplasia due to 21-hydroxylase deficiency (LOCAH) were studied. Patients were treated with Diane 35 for four months. Fasting blood samples for the determination of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone and dihydroepiandrosterone sulfate (DHEAS) and 24-hour urine collections for the determination of 6-sulfatoxymelatonin (aMT6s) excretion were obtained from all patients at baseline and after 4 months of treatment. Results were compared with those obtained in 15 control women. At baseline, women with PCOS and LOCAH had significantly higher testosterone and aMT6s values than women with IH and controls. Diane 35 treatment significantly decreased testosterone, LH, FSH and aMT6s values in PCOS and LOCAH patients compared with pretreatment values. These results indicate that hyperandrogenic women with PCOS and LOCAH have increased melatonin production. The decrease in aMT6s excretion together with reduced serum LH, FSH, DHEAS and testosterone values during treatment with cyproterone acetate-ethinyl estradiol, suggest that sex steroids either directly or through the suppression of gonadotropins, modulate melatonin secretion in these patients.

Urinary 6-sulfatoxymelatonin excretion in hyperandrogenic women with polycystic ovary syndrome: the effect of ethinyl estradiol-cyproterone acetate treatment

The role of melatonin in human reproduction is still unknown. Data obtained in patients with hypogonadism and precocious puberty suggest that melatonin and the reproductive hormones are interrelated. The aim of this study was to determine melatonin production in hyperandrogenic women. We studied 12 women with polycystic ovary syndrome (PCOS) and 10 women with idiopathic hirsutism (IH). Patients were treated with cyproterone acetate-ethinyl estradiol (Diane 35) for 4 months. Fasting blood samples for the determination of luteinizing hormone (LH), follicle-stimulating hormone (FSH), testosterone and dehydroepiandrosterone sulfate (DHEAS) and 24-h urine collections for the determination of 6-sulfatoxymelatonin (alpha MT6s) excretion were obtained from all patients at baseline and after 4 months of treatment. The results were compared with those obtained in 15 control women. At baseline, women with PCOS had significantly higher LH and testosterone levels than those with IH and controls. Their alpha MT6s values (52.6 +/- 20.3 micrograms/24 h) were significantly higher than the values in women with IH (34.3 +/- 7.1) and controls (30.5 +/- 6.5) (p < 0.001). Diane 35 treatment significantly decreased LH, FSH, testosterone and alpha MT6a values in PCOS (28.0 +/- 13.9 micrograms/24 h) (p < 0.0001). These results indicate that women with PCOS have increased melatonin production. The normalization of alpha MT6s and testosterone values during Diane 35 treatment suggests that sex steroids modulate melatonin secretion in these patients either directly or through the suppression of gonadotropin.

Seminal plasma androgen/oestrogen balance in infertile men

The hypothesis that the balance between oestrogen and androgen in seminal plasma is important for normal fertility was investigated. We determined the concentrations of oestradiol and testosterone in blood and seminal plasma from 62 infertile men and 32 normozoospermic men. Infertile men were classified according to semen analysis (concentration, motility and morphology): asthenozoospermia, oligozoospermia and oligoteratoasthenozoospermia. Serum luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were determined in all participants. For all subjects, mean testosterone levels were lower and mean oestradiol were higher in seminal plasma than in blood. Seminal plasma testosterone levels were lower in the infertile groups vs. control men ( p < 0.0002). Oligpzoospermic and oligoteratoasthenozoospermic men had significantly higher seminal plasma oestradiol levels compared with controls ( p < 0.03). The three infertile groups had significantly lower seminal plasma testosterone/oestradiol ratio than control men ( p < 0.001). Sperm analysis data (concentration, motility and morphology) significantly correlated with seminal plasma testosterone/oestradiol ratio. The findings of elevated seminal plasma oestradiol, decreased testosterone and testosterone/oestradiol ratio in infertile men, and the significant correlation between hormone levels and sperm analysis data suggest that the local balance between androgen and oestrogen is important for spermatogenesis.

Seminal plasma melatonin and gonadal steroids concentrations in normal men

The authors determined semen quality and the concentrations of estradiol, testosterone, and melatonin in blood and seminal plasma of 8 normal men. To investigate the reproducibility of these parameters, semen analysis and hormone concentrations were determined on 3 occasions, 6 weeks apart. All 8 men had normal semen analysis. Blood melatonin (9.7-45.4 pg/mL) and testosterone (3.5-12.3 ng/mL) levels were significantly higher than the comparable seminal plasma levels (0.6-5.0 pg/mL, p <.02; 0.1-0.9 ng/mL, p <.0001, respectively). Seminal plasma estradiol levels (46.9-91.3 pg/mL) were significantly higher than the blood levels (13.3-44.7 pg/mL) (p <.0001). The intraindividual variations in seminal plasma estradiol levels ranged between 8.7 and 13.8%. There was no correlation between sperm concentration, motility or morphology and blood or seminal plasma hormone levels. Also, blood and seminal plasma hormone levels were not correlated. These results indicate that in normospermic men seminal plasma estradiol levels are higher than blood hormone levels, suggesting local production of estradiol. This may imply that estrogen and/or the balance andorgen/estrogen is important in normal human spermatogenesis.

Increased urinary 6-sulfatoxymelatonin excretion in women with non-classical steroid 21-hydroxylase deficiency

OBJECTIVES

To determine melatonin production in hyperandrogenic women.

MATERIAL AND METHODS

Seventeen women with late onset adrenal hyperplasia due to 21-hydroxylase deficiency (LOCAH) and 15 control women were studied in early follicular phase of the menstrual cycle. Fasting serum levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), estradiol (E(2)), testosterone, dihydroepiandrosterone sulfate (DHEA-S), 17-hydroxyprogesterone (17-OHP) as well as the peak 17-OHP response to ACTH (250 microg IV) and 24h urinary 6-sulfatoxymelatonin (aMT6s) were determined in all participants.

RESULTS

All 17 hyperandrogenic women were carrying mutations of the CYP21 gene. Women with LOCAH had significantly higher serum testosterone, DHEA-S, 17-OHP and ACTH stimulated 17-OHP values compared with controls. Their aMT6s values (44.6+/-20.3 microg/24h) were significantly higher than the values in control women (31.5+/-20.3) (p<0.03). The urinary aMT6s values were positively correlated with testosterone (p<0.04), DHEA-S (p<0.02) and peak 17-OHP (p<0.04).

CONCLUSIONS

Women with LOCAH have increased melatonin production. There is a relationship between adrenal androgens and melatonin in these women.

Increased 6-sulfatoxymelatonin excretion in women with polycystic ovary syndrome

OBJECTIVE

To determine melatonin production in hyperandrogenic women.

DESIGN

Controlled prospective study.

SETTING

Outpatients in an academic medical center.

PATIENT(S)

Twenty-two women with polycystic ovary syndrome (PCOS), 20 women with idiopathic hirsutism, and 15 age-matched individuals who had similar body mass indexes as controls.

INTERVENTION(S)

Fasting blood samples and 24-hour urinary samples were obtained from all participants.

MAIN OUTCOME MEASURE(S)

All participants provided serum samples for the measurement of LH, FSH, testosterone, E(2), DHEAS, 17 alpha-hydroxyprogesterone (17-OHP), and insulin levels, as well as urinary 6-sulfatoxymelatonin (aMT6s).

RESULT(S)

Women with PCOS had higher aMT6s, testosterone, LH/FSH ratio, and insulin values than either women with idiopathic hirsutism or control women. Testosterone inversely correlated with aMT6s in PCOS. Regression analysis revealed that only testosterone was an important determinant of aMT6s in PCOS.

CONCLUSION(S)

Women with PCOS have increased melatonin production.

Actigraphic sleep-wake patterns and urinary 6-sulfatoxymelatonin excretion in patients with Alzheimer's disease

Recent studies suggest melatonin, due to its antioxidant and free-radical-scavenging actions, may play a role in the neuroprotection against amyloid, which is implicated in the pathogenesis of Alzheimer's disease (AD). In this study, we determined urinary 6-sulfatoxymelatonin (aMT6s) excretion together with actigraphic sleep-wake patterns of untreated male patients with AD who lived at home. Results were compared with those obtained from normal age-matched elderly and normal young male subjects. Similar measurements were also performed in another group of patients with AD who were treated with a cholinesterase inhibitor (Donepezil, Aricept). Total 24h aMT6s values were significantly reduced in elderly controls (19.9h +/- 5.2 microg/ 24h), in those with untreated AD (12.7 +/- 4.4 microg/24h), and in patients treated for AD (12.4 +/- 4.4 microg/24h) compared with normal young men (32.8 +/- 3.1 microg/24h). A day-night difference in aMT6s was evident in all young controls, in 50% of elderly controls, in only 20% of patients with untreated AD, and in 67% of those with AD receiving Aricept. Sleep quality (expressed as sleep efficiency, wake time, and long undisturbed sleep duration) was better in young and elderly controls compared with the two groups of patients with AD. There was no significant correlation between aMT6s values or sleep patterns and the severity of cognitive impairment in patients with AD. Taken together, these data suggest that disrupted sleep, decreased melatonin production, and partial lack of day-night difference in melatonin secretion were observed equally in normal elderly and in patients with AD. Our results do not permit drawing any conclusion as to whether changes in urinary aMT6s excretion is correlated with disturbed sleep in patients with AD.

Disruption of the nocturnal testosterone rhythm by sleep fragmentation in normal men

Recently, we have demonstrated that in normal men the nocturnal testosterone rise antedated the first rapid eye movement (REM) sleep episode by about 90 min and was correlated with REM latency. To further elucidate whether the diurnal testosterone rhythm is a sleep-related phenomenon or controlled by the circadian clock, we determined serum testosterone levels in 10 men during the ultrashort 7/13 sleep-wake cycle paradigm. Using this schedule, subjects experienced partial sleep deprivation and fragmented sleep for a 24-h period. Serum testosterone levels were determined every 20 min between 1900-0700 h with simultaneous sleep recordings during the 7-min sleep attempts. The results were compared with those obtained in men during continuous sleep. Although mean levels and area under the curve of testosterone were similar in both groups, fragmented sleep resulted in a significant delay in testosterone rise (03:24 h +/- 1:13 vs. 22:35 h +/- 0:22). During fragmented sleep, nocturnal testosterone rise was observed only in subjects who showed REM episodes (4/10). Our findings indicate that the sleep-related rise in serum testosterone levels is linked with the appearance of first REM sleep. Fragmented sleep disrupted the testosterone rhythm with a considerable attenuation of the nocturnal rise only in subjects who did not show REM sleep.

Decreased melatonin secretion in a phenotypically male 46,XX patient with classic 21-hydroxylase deficiency

The possible role of gonadal steroids and gonadotropins in regulating melatonin secretion has been suggested in clinical syndromes of the hypothalamic-pituitary-gonadal axis. We describe the results of melatonin secretion in a 37-year old male patient who presented with azoospermia. The patient was an XX male, had classic simple virilizing form of 21-hydroxylase deficiency, which led to a masculine phenotype. He was ovariectomized at the age of three years and reared as a male. Melatonin production (aMT6s) was determined at baseline and during 12 months of replacement therapy. Results were compared with those obtained in age-matched male controls. Pretreatment aMT6s values were decreased (14.3 microg/24 h vs. 29.0+/-5.5 in controls). Dexamethasone replacement was associated with an increase in aMT6s values (19.3-20.9 microg/24 h). The addition of testosterone to dexamethasone replacement resulted in normalization of aMT6s (27.6-33.1 microg/24 h) and serum 17OH progesterone, testosterone and estradiol levels. The present data indicate that androgen excess due to 21 hydroxylase deficiency is associated with decreased melatonin secretion. These results support the hypothesis that sex steroids modulate melatonin secretion.

Melatonin hypersecretion in male patients with adult-onset idiopathic hypogonadotropic hypogonadism

Increased melatonin secretion observed in male patients with congenital isolated hypogonadotropic hypogonadism and its normalization during testosterone treatment had suggested that melatonin and the reproductive hormones are inter-related. Since these patients have a congenital form of hypogonadism, it is likely that hypermelatoninemia is the consequence of hypogonadism. To further study the relations between the pineal and the reproductive axis in humans, we evaluated melatonin secretion in two men (aged 35 and 50 yrs.) with acquired adult-onset hypogonadotropic hypogonadism. The diagnosis was based on the findings of normal testicular volume, azoospermia, low serum testosterone, normal LH and FSH levels, but apulsatile LH secretion, and intact anterior pituitary hormones secretion, normal findings on skull radiographic imaging, prior sexual maturation and paternity. Melatonin secretion was assessed as urinary 24 h 6-sulphatoxymelatonin excretion (aMT6s) prior to and during the administration of 250 mg testosterone enanthate per month for 4 months. Pretreatment melatonin production was markedly increased in both patients: 427-915 ng/kg/24 h vs. 204+/-81 [mean+/-SD] in 16 age-matched male controls. During testosterone treatment, aMT6s levels were normalized in one patient (range: 81-287 ng/kg/24 h) and remained elevated in the other patient (range: 830-1280 ng/kg/24 h). These data indicate that male patients with acquired GnRH deficiency have increased melatonin secretion. Melatonin hypersecretion in these patients may reflect a functional association.

Management of benign thyroid nodules based on the findings of fine-needle aspiration

Fine-needle aspiration (FNA) biopsy is a safe, simple, and inexpensive procedure that is particularly applicable for lesions of the head and neck. In our department, it is widely used for the evaluation of thyroid nodules. A total of 189 patients participated in a prospective study of benign thyroid nodules. Our aim was to verify the modality of treatment used in our department and the reliability of benign cytologic results of colloid goiter. All patients had cold nodules on thyroid scanning. The patients were divided into two groups, the first comprising 93 patients who did not undergo thyroid surgery and were followed up for 5 to 11 years. One case of malignancy was found in this group during the follow-up. The second group was comprised of 96 patients who were operated on despite FNA results of colloid goiter. Among them, five cases of malignancy were found. Four of these five cases could not be regarded as FNA failure. Our study confirms that the combination of clinical findings with those of the FNA is a reliable approach to the management of benign thyroid nodules. Nevertheless, long-term follow-up is mandatory and repetitive aspirations should be considered.

Endocrine activity during sleep

Almost all functions of humans are subject to cyclic changes and are governed by the nervous system. Most rhythms are driven by an internal biological clock located in the hypothalamic suprachiasmatic nucleus (SCN) and can be synchronized by external signals such as light-dark cycles. Homeostatic activities such as body temperature, blood volume, water balance and sleep, are rhythmic. Likewise, most hormones are secreted in a rhythmic fashion. Both sleep and circadian effects interact to produce the overall rhythmic pattern of the pituitary and pituitary-dependent hormones. Some of the 24-h hormonal rhythms depend on the circadian clock (ACTH, cortisol and melatonin), or are sleep related (prolactin and TSH). GH secretion is influenced by the first slow wave sleep (SWS) episode at the beginning of the night. Pulses of prolactin and GH are positively linked to increases in delta wave activity, i.e. deepest phases of sleep, occurring primarily during the first third of the night. Pulses of TSH and cortisol are related to superficial phases of sleep. As a result of the consolidation of the sleep period in humans, the wake-sleep transition is associated with physiological changes with the endocrine system being part of the adaptive mechanism to reduce physical activity during sleep.

Long-term melatonin administration does not alter pituitary-gonadal hormone secretion in normal men

The role of melatonin in the regulation of reproduction in humans is still controversial. In the present study the effects of melatonin were examined, 6 mg given orally every day at 1700 h for 1 month in a double-blind, placebo controlled fashion, on the nocturnal secretory profiles of luteinizing hormone (LH), follicle stimulating hormone (FSH), testosterone and inhibin beta in six healthy adult men. Serum concentrations of LH, FSH, testosterone and inhibin beta were determined before and after treatment every 15 min from 1900 to 0700 h over 3 nights in a controlled dark-light environment with simultaneous polysomnographic sleep recordings. The following sleep parameters were determined: total recording time, sleep latency, actual sleep time, sleep efficiency, rapid eye movement (REM) sleep latency and percentages of sleep stages 2, 3/4 and REM. There were no statistically significant differences in all sleep parameters between baseline and placebo or between baseline and melatonin except for longer REM latency and lower percentage REM at baseline than under melatonin treatment. These are explained as reflecting first-night effect at baseline. The mean nocturnal LH, FSH, testosterone and inhibin beta integrated nocturnal secretion values did not change during the treatment period. Likewise, their pulsatile characteristics during melatonin treatment were not different from baseline values. Taken together, these data suggest that long-term melatonin administration does not alter the secretory patterns of reproductive hormones in normal men.

Prevalence of hypothyroidism and diabetes mellitus in elderly kibbutz members

The aim of this study was to determine the prevalence of hypothyroidism and diabetes mellitus (DM) in elderly (aged 65-92 years) kibbutz members in Northern Israel.

METHOD

The medical records of 1096 elderly (642 females and 454 males) residing in 11 kibbutzim were reviewed for data regarding thyroid function tests (TSH and FT4) and fasting blood glucose. Fasting blood glucose levels above 7.8 mmol/l was considered diagnostic for diabetes mellitus.

RESULTS

The prevalence of hypothyroidism was 14% (9.7% in males and 18.2% in females) and that of DM was 11.5% (12.1% in males and 11.1% in females). In 74% of the diabetics the diagnosis was made after the age of 60 years. Distribution of treatment modalities in diabetics was as follows: diet only 42%. oral hypoglycemic agents 52% and Insulin 6%. Subclinical hypothyroidism (serum TSH levels above 4.5 mU/L with normal FT4 levels) was detected in 38% of all the hypothyroid subjects.

CONCLUSION

The data suggest that diabetes mellitus and primary hypothyroidism are common disorders in elderly subjects. DM in the elderly can usually be handled with diet and oral hypoglycemic drugs. Since the clinical features of hypothyroidism in the elderly are often atypical, we suggest that elderly subjects should be screened for hypothyroidism.

The association between melatonin and sleep stages in normal adults and hypogonadal men

The role of melatonin in normal sleep-wake regulation has been inferred from the temporal relationships between its cycle and the 24 h cycle in sleep propensity. Pharmacological doses of melatonin were reported to have sleep-inducing effects in insomniacs. The current study investigated the relationship between melatonin and sleep stages in groups of hypogonadal men with abnormal melatonin levels. We were also interested in examining what would happen to these relationships during testosterone replacement therapy. Male patients with hypogonadotropic hypogonadism (IGD, n = 6), constitutional delayed puberty (DP, n = 6), and Klinefelter's syndrome (KS, n = 5) before and during testosterone replacement therapy were studied. Six patients with KS and normal testosterone levels were also studied. Results were compared with those obtained in normal controls (n = 6). Serum samples were obtained at 15 min intervals from 1900-0700h in a controlled light-dark environment with simultaneous polysomnographic sleep recordings. Serum melatonin levels were the highest in IGD and DP and lowest in KS patients. A lower percentage of sleep stage 2 and higher percentage of stage 3/4 were observed in IGD and DP groups while KS patients had higher percentage of stage 2 and lower percentage of stage 3/4 as compared to controls. Slow wave sleep was the highest in IGD and the lowest in KS groups. Serum melatonin levels were lowest in KS groups. Serum melatonin levels were lowest in sleep stage 3/4, higher in stage 2 and highest in REM sleep when all groups were combined and averaged together. However, in the IGD group, melatonin levels were actually lowest in REM sleep. Also in the KS group, melatonin levels were lower in REM than during sleep stage 2. Serum melatonin levels were lowest in sleep stage 3/4 in all groups, higher in stage 2, and highest in REM sleep. During waking periods, melatonin levels were the highest in untreated IGD, DP and KS patients. Testosterone treatment given to these patients, although normalized, their melatonin levels did not statistically significantly change these correlations. These data demonstrate that relative melatonin concentrations are associated with sleep stages in hypogonadal and normal men. The results also indicate that the association between melatonin and the reproductive hormones are independent of the synchronizing effects of melatonin on sleep homeostasis.

Relationship between rapid eye movement sleep and testosterone secretion in normal men

The relation between the pituitary-gonadal hormones' rhythm and sleep physiology in men is not fully elucidated. To examine whether the reproductive hormones are correlated with sleep architecture, we determined the nocturnal serum levels of testosterone, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) in six healthy young men. Serum hormone levels were obtained every 15 minutes from 1900 to 0700 hours with simultaneous polysomnographic sleep recordings. Hourly testosterone levels were lowest when subjects were awake (1900-2200 hours) than during sleep (2300-0700 hours). Testosterone nocturnal rise antedated the first REM by about 90 minutes. The rise in testosterone levels was slower when REM latency was longer. Mean nocturnal testosterone levels did not correlate with the number of rapid eye movement (REM) episodes. Also, pre-non-REM (NREM) testosterone levels were higher as compared with the pre-REM periods and lower during the first NREM period as compared with other nocturnal NREM periods. Serum LH levels disclosed a nocturnal rise that preceeded a similar rise in testosterone by about an hour. We conclude that in young adult men, testosterone levels begin to rise on falling asleep, peak at about the time of first REM, and remain at the same levels until awakening.

Auditory brain-stem evoked potentials in patients with thyroid and parathyroid dysfunction: adaptation to chronic hormonal dysequilibrium

Auditory Brainstem Evoked Potentials (ABEPs) and pure tone audiograms were obtained from 24 patients with parathyroid dysfunction (17 hypercalcemia and 7 hypocalcemia) and 12 patients with thyroid dysfunction (6 hyperthyroid and 6 hypothyroid) and from 10 control subjects. ABEPs were characterized by I-V interpeak latency difference at 10/sec click rate and by the effect of increasing stimulus rate to 55/sec. None of the ABEP measures were significantly affected by levels of serum calcium, thyroid hormones or their interactions. Moreover no correlation was found between biochemical and electrophysiological measures. This stability of ABEP measures contrasts with earlier reports on acute effects of calcium and thyroid hormonal levels on auditory brainstem evoked potentials. We propose that chronic calcium or thyroid hormonal homeostatic changes are associated with adaptive mechanisms resulting in normal function of the auditory brainstem.

Melatonin and sex hormone interrelationships--a review

Melatonin, the main hormone secreted by the pineal gland at night, plays a major role in regulating reproductive physiology in seasonal breeders and influences the age of sexual maturation in laboratory rodents. In humans these relationships are less clear. Evidence supporting a melatonin-reproductive hormone relationship relies on findings of abnormal melatonin secretion in disorders of the reproductive system and on pathologies of the pineal gland which are associated with clinical abnormalities of the reproductive hormones. Normal melatonin rhythms are closely related to those of the reproductive hormones during infancy and reciprocally correlated during puberty. The demonstration of melatonin receptors in the brain and in reproductive organs, together with the localization of sex hormone receptors in the pineal gland, further strengthen these relationships. However, it is not yet clear that these correlations are functionally related, as data on the antigonadal effects of exogenous melatonin on the reproductive hormones are not conclusively established.

Melatonin administered in the afternoon decreases next-day luteinizing hormone levels in men: lack of antagonism by flumazenil

The role of melatonin in the regulation of human reproduction remains unclear. In the present study, we examined the influence of exogenous melatonin on pulsatile luteinizing hormone (LH), diurnal rhythm of testosterone, and endogenous melatonin profile in six healthy young adult males. To test the hypothesis that the effect of melatonin on LH or testosterone secretory patterns may be mediated through the benzodiazepine-(BNZ) gamma-amino-butyric acid (GABA) receptor complex, a benzodiazepine receptor antagonist (Flumazenil) was administered. The study design comprised four 10-h (4:00 PM-2:00 AM) testing periods. During each experimental period, subjects were given an oral dose of placebo, or 3 mg melatonin or 10 mg flumazenil, at 5:00 PM, in a randomized, double-blind, partially repeated Latin square design in the following combinations: placebo-placebo, placebo-melatonin, flumazenil-placebo, and flumazenil-melatonin. The following day, serum samples were obtained every 20 min between 4:00 PM and 2:00 AM in a controlled light-dark environment for the determination of LH and melatonin levels. Serum testosterone concentrations were determined every 20 min between 7:00 and 8:00 AM and 7:00 and 8:00 PM. A significant decrease in mean serum LH levels (p < 0.02) was observed in the melatonin-treated groups as compared with placebo-flumazenil groups. There was no change in LH pulse frequency, testosterone levels, or in melatonin onset time and amplitude. No additional effect of flumazenil on LH or testosterone levels was observed. These data indicate that an evening melatonin administration decreases the next-day LH secretion in normal adult males without altering testosterone levels or the endogenous nocturnal melatonin secretory pattern. This effect of melatonin is not mediated through the benzodiazepine-GABA receptor complex.

[Diagnosis of hyperprolactinemia: determination of prolactin level at rest]

We present 3 women who were referred for evaluation of stress-related mild-to-moderate hyperprolactinemia. This frequent finding may mistakenly be considered a clinical problem, and lead to inappropriate investigation and therapy. We emphasize the importance of serial blood sampling for prolactin determination. We collected blood samples repeatedly under resting conditions from an indwelling venous brachial catheter, every 30 minutes for a total of 6 samples. All 3 patients had normal prolactin levels 30-60 minutes after starting the test. Neither further investigation nor medical therapy were needed and these anxious patients were reassured that their hyperprolactinemia was factitious.

Daily and seasonal variations in the concentration of melatonin in the human pineal gland

To elucidate whether pineal melatonin secretion is affected by changes in day length, we determined the concentration of melatonin in human pineal glands obtained at autopsy from 66 male subjects, aged 16-84 years over a period of 12 consecutive months. Based on the time of death, a day-night difference in pineal melatonin levels was evident only in the long photoperiod (April-September) with significantly higher melatonin concentrations occurring at night (2200-1000 h). Nighttime values in the long photoperiod were significantly higher than the nighttime values during the short photoperiod (October-March). During the short photoperiod, the data suggested a possible phase-delay in melatonin secretion. Day-night difference was evident in young subjects (30-60 years), but not in elderly subjects (61-84 years). Elderly subjects had lower total melatonin levels (day and night values) although statistically not significant. Therefore, melatonin levels did not decline with age and when the data were analyzed by age there was no significant day-night difference in melatonin levels. These data indicate that the concentration of melatonin in the human pineal is augmented only during the long photoperiod. The results suggest a partial effect of photoperiod on melatonin secretion in humans. This may result from living in an artificial light environment or due to other nonphotic signals involved in generating melatonin rhythm.

Basement membrane material (hyaline globules) in synovial sarcoma. A case report with description of a potential diagnostic pitfall

BACKGROUND

Synovial sarcoma (SS), a malignant mesenchymal tumor, has a biphasic growth pattern characteristically. Histologically and cytologically the tumor can pose diagnostic difficulty when the epithelial component is predominant.

CASE REPORT

A 22-year-old female presented with a rapidly enlarging mass on the lower left side of the neck. Fine needle aspiration of the tumor yielded abundant, discohesive round-oval cells mingled with amorphous hyaline material, raising a suspicion of medullary carcinoma of the thyroid. In addition, air-dried, Giemsa-stained smears demonstrated rosettelike structures with central magenta globular material, mimicking adenoid cystic carcinoma. However, histologic examination of the excised tumor, including immunohistochemical and ultrastructural studies, proved it to be a typical SS with copious basement membrane accumulations.

CONCLUSION

The cytologic appearance of SS can be confusing. However, a false diagnosis may be avoided if adequate needle sampling is ensured and clinical correlation considered.

Transient cold nodule of the thyroid due to localized postpartum thyroiditis

A 27-year-old woman with no previous personal or family history of thyroid disease was referred to us for the evaluation of thyroid nodule, five months postpartum. Thyroid scintigraphy demonstrated a left cold nodule. Fine needle aspiration cytology of the nodule showed a mixture of colloid, follicular cells and lymphocytes, suggesting lymphocytic thyroiditis. Thyroid function tests were normal and thyroid autoantibodies were negative. After two months the thyroid nodule was not palpated and thyroid scintigraphy returned to normal. Thyroid function tests remained normal twelve months after delivery. These findings suggest that postpartum thyroiditis may present as a localized transient form and should be considered in the differential diagnosis of painless solitary nodule that appears postpartum.

Seasonal variation of gonadotropins and gonadal steroids receptors in the human pineal gland

Recently abnormal melatonin secretion was demonstrated in hypogonadal male patients which was normalized during testosterone administration. These results suggested that both gonadal steroids and gonadotropins may modulate melatonin secretion, probably by activating specific receptors in the pineal gland. We used immunohistochemistry to localize luteinizing hormone, follicle stimulating hormone, estrogen and androgen receptors in human pineal glands. Tissues were obtained at autopsy from 53 adult males (aged 19-94 years) over a period of 1 year. Positive staining for the four types of receptors was evident in all 53 specimens examined. The percent of positively stained cells revealed a significant seasonal variation of gonadotropin receptors with higher values in the winter than in the summer. Day-night difference was evident only for follicle stimulating hormone-receptors during the summer and winter, with higher values at night. Androgen receptors and estrogen receptors were present in all specimens but did not reveal day-night or seasonal variations. These data demonstrate the presence of gonadotropin and gonadal steroid receptors in the human pineal gland. Gonadotropin receptors exhibited seasonal variation with higher values in the winter.

Pheochromocytoma due to unilateral adrenal medullary hyperplasia

We describe two male patients, aged 17 and 47 years, with clinical and biochemical features of pheochromocytoma. Both patients had normal-sized adrenal glands on abdominal CT scan and abnormal unilateral uptake of I-123 metaiodobenzylguanidine (MIBG) on scintigraphy. The surgical adrenalectomy revealed normal macroscopic glands in both patients. Histological examination showed adrenal medullary hyperplasia with adrenal cortico-medullary ratios of 2:1 and 4:1. Unilateral adrenalectomy resulted in amelioration of symptoms and normalization of catecholamines excretion. DNA examination for RET protooncogene revealed no mutations in exons 10, 11, 13, 14 and 16. Our results suggest that diffuse adrenal medullary hyperplasia may be the initial pathological change in the adrenal gland leading, subsequently, to the development of nodular hyperplasia and adrenal medullary tumor. These results indicate that the syndrome of pheochromocytoma may occur as an unilateral adrenal medullary hyperplasia in patients without evidence for multiple endocrine neoplasia.

Abnormal melatonin secretion in hypogonadal men: the effect of testosterone treatment

OBJECTIVE

We have recently demonstrated that GnRH deficient male patients have increased nocturnal melatonin secretion, whereas hypergonadotrophic hypogonadal males have decreased melatonin levels. We were interested in determining whether testosterone (T) treatment (when T levels were well matched with pubertal control values) has an effect on melatonin secretory profiles in these patients.

DESIGN

Prospective, controlled.

SUBJECTS

Six male patients with idiopathic hypogonadotrophic hypogonadism (IGD), six males with hypergonadotrophic hypogonadism due to Klinefelter's syndrome (KS) and seven controls. Patients were examined before and during the administration of 250 mg testosterone enanthate/month for four months.

MEASUREMENTS

Serum samples for melatonin levels were obtained every 15 minutes from 1990 to 0700 h in a controlled light-dark environment. The results of FSH, LH, T and oestradiol (E2) (determined at hourly intervals) and melatonin profiles, were compared with the pre-treatment values in each group, and with values obtained in the control group.

RESULTS

All 12 patients had low pre-treatment T levels (1.4 +/- 0.7 in IGD and 2.0 +/- 0.4 in KS vs. 19.8 +/- 2.3 nmol/l in controls) and attained normal levels after four months of T treatment (19.5 +/- 7 in IGD and 22.7 +/- 3.8 nmol/l in KS). Serum LH, FSH and E2 levels (11 +/- 4 IU/l, 24 +/- 10 IU/l and 113 +/- 12 pmol/l, respectively) were still elevated in KS during T treatment as compared with values in controls (2 +/- 1 IU/l, 2 +/- 1 IU/l and 67 +/- 4 pmol/l, respectively). In IGD, serum LH (0.12 +/- 0.1 IU/l) and FSH (0.16 +/- 0.2 IU/l) levels during T treatment were suppressed. Pretreatment melatonin levels in IGD were greater than those in age-matched pubertal controls while in KS, melatonin levels were lower than values in controls. Melatonin levels were equal in all 12 hypogonadal patients and controls when T levels were well matched. Mean (+/- SD) dark-time melatonin levels decreased from 286 +/- 18 to 157 +/- 26 pmol/l in IGD and increased from 92 +/- 19 to 183 +/- 48 pmol/l in KS (vs 178 +/- 59 pmol/l in controls). The integrated melatonin values decreased in IGD (from 184 +/- 14 to 102 +/- 21 pmol/min. 1 x 10(3)) and increased in KS (from 64 +/- 13 to 123 +/- 40, vs. 116 +/- 39 pmol/min. 1 x 10(3) in controls). No correlations were found between melatonin and LH, FSH or E2 levels.

CONCLUSIONS

These data indicate that male patients with GnRH deficiency have increased nocturnal melatonin secretion while in hypergonadotrophic hypogonadal males melatonin secretion is decreased. Testosterone treatment normalized melatonin concentrations in these patients. Taken together, the results suggest that GnRH, gonadotrophins and gonadal steroids modulate pineal melatonin in humans.

Nocturnal melatonin onset is phase locked to the primary sleep gate

In this study, we used the "ultrashort sleep-wake paradigm" (7/13), which measures sleep propensity three times an hour for 29 h, from 0700 to 1200 the next day, on 6 healthy male subjects concomitantly with melatonin plasma level. Melatonin was measured once an hour during the morning and early afternoon of the first day and three times an hour from 1600 to 1000 the following morning. Rectal temperature was measured continuously for four subjects. Subjects underwent the 7/13 paradigm three times, and in all three sessions consistent phase relationships were found between the nocturnal onset of melatonin secretion and opening of the nocturnal sleep gate; also, there was an inverse relationship between melatonin and core body temperature and an almost perfect out-of-phase relationship between sleep propensity and temperature, with the temperature peak falling precisely in the middle of the "forbidden zone" for sleep, i.e., the early evening nadir in sleepiness. On the basis of these phase relationships and previous findings from our laboratory on the effects of exogenous melatonin on the sleep propensity function, we conclude that melatonin participates in sleep-wake regulation in humans.

Immunohistochemical localization of gonadotropin and gonadal steroid receptors in human pineal glands

Recently, we demonstrated that melatonin secretion was increased in male patients with GnRH deficiency and decreased to normal levels during testosterone treatment. These data suggested that gonadal steroids modulate melatonin secretion, probably by activating specific receptors in the pineal gland. We used immunohistochemistry to localize gonadotropin (LH and FSH) and gonadal steroid (androgens and estrogens) receptors in human pineal glands. Tissues were obtained at autopsy from 25 males, aged 19-87 yr, and five prepubertal children, aged 0.2-10 yr. Positive staining for all four types of receptors (LH, FSH, androgen, and estrogen) in the pineal parenchymal cells, pinealocytes, was evident in all 30 glands examined. Double staining revealed that nuclear receptors (androgen or estrogen) co-existed with cytoplasmatic receptors (LH or FSH) in the same cells. The results demonstrate the presence of gonadotropin and gonadal steroid receptors in human pinealocytes from infancy to old age.

Pulsatile patterns of melatonin secretion in patients with gonadotropin-releasing hormone deficiency: effects of testosterone treatment

Recently, we have demonstrated that male patients with gonadotropin-releasing hormone (GnRH) deficiency had increased nocturnal melatonin secretion that decreased to normal levels during testosterone treatment. The purpose of the current study was to examine if the abnormally increased melatonin levels in these patients were associated with pulsatile secretory patterns, and, if these were modified during testosterone administration. Characteristics of nocturnal melatonin and luteinizing hormone (LH) secretion were compared in six normal young males, six males with idiopathic hypogonadotropic hypogonadism (IGD), and in six males with constitutional delayed puberty (DP). Patients were examined in the untreated state and following the administration of 250 mg testosterone enanthate/month for 4 months. Serum samples for melatonin and LH levels were obtained every 15 min from 19.00 hr to 07.00 hr in a controlled light-dark environment. Pulse detection and pulse characteristics were determined by the program ULTRA. In comparison with normal controls, untreated IGD patients showed significantly higher pulse frequency, lower relative increments and shorter half-life times for melatonin. Similar findings were observed in DP patients, although statistically of borderline significance. Treatment with testosterone normalized melatonin pulse characteristics in both IGD and DP patients. The secretory pattern of LH release in these patients was characterized by significantly higher relative and absolute increments and shorter half-life time without any significant change in the number of LH pulses. Taken together, these data suggest that melatonin is secreted in a pulsatile pattern in normal adult males and in male patients with GnRH deficiency. The abnormally increased nocturnal melatonin secretion observed in these patients may indicate that the pineal pulse generator is expressing an altered activity pattern within its normal capabilities. Testosterone administration normalized melatonin secretory patterns in IGD and DP patients. The lack of relationship between the pulsatile LH and melatonin secretory patterns suggest an independent signal for the nocturnal pulsatile melatonin and LH secretions.

Recovery from metabolic bone disease in a girl with vitamin D deficiency rickets associated with primary hyperparathyroidism

We describe a 13 year-old Ethiopian girl with vitamin D deficiency rickets. Hypercalcemia, increased serum alkaline phosphatase and PTH levels, together with low serum levels of 25-hydroxyvitamin D and 24,25-dihydroxyvitamin D suggested the co-existence of primary hyperparathyroidism. The surgical removal of a parathyroid adenoma led to bone healing and normalization of blood chemistry. We conclude that vitamin D deficiency masked the hyperparathyroidism and hypercalcemia, while excess PTH secretion delayed the cure of rickets until successful parathyroidectomy had been carried out.

Decreased nocturnal melatonin secretion in patients with Klinefelter's syndrome

OBJECTIVE

We have recently demonstrated that GnRH deficient male patients have increased nocturnal melatonin secretion which decreases to normal levels during testosterone treatment. The results suggested that sex steroids, rather than LH, modulate pineal melatonin in an inverse fashion. The purpose of this study was to characterize circulating melatonin levels in untreated males with hypergonadotrophic hypogonadism due to Klinefelter's syndrome (KS).

DESIGNS

Prospective, controlled.

SUBJECTS

Eleven patients with Klinefelter's syndrome and seven controls. Patients were subdivided into two groups: (1) with low testosterone, and (2) with normal testosterone levels.

MEASUREMENTS

Serum samples for melatonin concentrations were obtained every 15 minutes from 1900 to 0700 h in a controlled light-dark environment.

RESULTS

All patients had elevated FSH, LH and oestradiol (E2) levels. Mean (+/-SD) dark time nocturnal melatonin levels were significantly lower in low testosterone KS (92 +/- 19 pmol/l) compared with 146 +/- 42 pmol/l in normal testosterone KS and 179 +/- 59 pmol/l in controls (P < 0.02). A similar pattern was observed for the mean (+/-SD) peak melatonin levels (165 +/- 41, 236 +/- 59 and 293 +/- 89 pmol/l) in low testosterone KS, normal testosterone KS and controls, respectively (P < 0.01). Integrated nocturnal melatonin secretion values (AUC) were also lower in low testosterone KS (64 +/- 13) compared with 96 +/- 26 in normal testosterone KS and 116 +/- 39 pmol/min 1 x 10(3) in controls (P < 0.02). The time of melatonin peak and the time of the nocturnal melatonin rise as well as the light-time mean (+/-SD) serum melatonin levels were similar in all three groups. No correlations were found between melatonin and LH, FSH, or E2 levels.

CONCLUSIONS

Melatonin secretion is decreased in male patients with low testosterone hypergonadotrophic hypogonadism whereas in normal testosterone Klinefelter's syndrome patients, melatonin secretory profiles are normal. The results suggest that the suppression of melatonin secretion in these patients is mediated by GnRH (either directly or indirectly) and/or oestradiol.

Nocturnal secretory patterns of melatonin, luteinizing hormone, prolactin and cortisol in male patients with gonadotropin-releasing hormone deficiency

To clarify whether disorders of gonadotropin releasing hormone (GnRH) deficiency are associated with altered melatonin and pituitary hormones secretory patterns, we studied male patients with hypogonadotropic hypogonadism (IGD; n = 6), delayed puberty (DP; n = 7) and age-matched pubertal controls (n = 7). Serum samples for the determination of melatonin, luteinizing hormone (LH), prolactin and cortisol levels were obtained at 15 min intervals from 1900 to 0700 in a controlled light-dark environment, complete bed-rest and fasting with simultaneous sleep recordings. Mean (+/- SD) dark-time melatonin levels were significantly higher in IGD (286 +/- 26 pmol/L) and DP (205 +/- 44 pmol/L) compared with 178 +/- 64 pmol/L in controls (P < 0.003). So were the mean (+/- SD) peak melatonin levels (453 +/- 63, 346 +/- 106 and 292 +/- 96 pmol/L) in IGD, DP and controls, respectively (P < 0.03). Integrated nocturnal melatonin (AUC) values were also higher in IGD and DP (184 +/- 15 and 134 +/- 28 pmol/min/L x 10(3)) compared with 116 +/- 42 pmol/min/L x 10(3) in controls (P < 0.003). The time of onset of the nocturnal melatonin rise was observed earlier in IGD and DP patients as compared to controls. No correlations were found between melatonin and LH levels, between melatonin and prolactin levels, or between melatonin and cortisol levels. These data indicate that melatonin secretion is enhanced in male patients with GnRH deficiency. The lack of correlation between melatonin and LH suggest that circulating gonadal steroids, rather than LH, modulate melatonin secretion in a reverse fashion.

[Hypokalemic periodic paralysis: a rare presentation of thyrotoxicosis]

Hypokalemic periodic paralysis is an uncommon complication of thyrotoxicosis, and very rare as a presenting symptom. It is most frequent in east Asian and Japanese males, but extremely rare in others. Only 1 case has previously been reported from Israel. We present a 29-year-old Arab man who presented with sudden paralysis of both legs. Physical examination revealed signs of thyrotoxicosis, and laboratory tests showed profound hypokalemia. Oral potassium resulted in rapid disappearance of symptoms, and after restoration of the euthyroid state, there were no further attacks. This case shows that thyrotoxic hypokalemic periodic paralysis is not confined to males of east Asian and Japanese origin, and that adequate treatment with oral potassium and antithyroid drugs is successful, and should be given as soon as possible.

Abnormal melatonin secretion in male patients with hypogonadism

Recently we have demonstrated that melatonin secretion is increased in untreated male patients with GnRH deficiency. Testosterone administration to these patients decreased melatonin secretion to normal levels. These data, however, did not exclude a gonadotropic effect on melatonin secretion. To further elucidate whether gonadal steroids and/or gonadotropins modulate melatonin secretion in humans we compared untreated young males with hypogonadotropic hypogonadism (IGD, n = 6), and hypergonadotropic hypogonadism caused by KlinEfelter's syndrome (KS, n = 11) to normal pubertal male controls (n = 7). KS patients were subdivided into two groups: KS-1, with low testosterone; and KS-2, with normal testosterone levels. Serum samples for melatonin concentrations were obtained every 15 min from 7 PM to 7 AM in a controlled light-dark environment with simultaneous sleep recordings. All KS patients had elevated gonadotropin levels and decreased melatonin levels. Mean (+/- SD) dark-time nocturnal melatonin levels in KS-1 were 92 +/- 21 pmol/L and were 146 +/- 46 pmol/L in KS-2 compared with 178 +/- 64 pmol/L in controls. Integrated nocturnal melatonin secretion values (AUC) were 64 +/- 14 pmol/min x L x 10(3) in KS-1 and 96 +/- 29 pmol/min x L x 10(3) in KS-2 compared with 116 +/- 42 pmol/min x L x 10(3) in controls. All IGD patients had low gonadotropin and testosterone levels. Their dark-time melatonin levels (286 +/- 26 pmol/L) and the AUC values (184 +/- 15 pmol/min/L x 10(3)) were increased. These data indicate that melatonin secretion is increased in male patients with GnRH deficiency and decreased in low testosterone hypergonadotropic hypogonadal patients. Taken together, our results suggest that both gonadotropins and gonadal steroids modulate melatonin secretion in humans.

Nocturnal melatonin and luteinizing hormone rhythms in women with hyperprolactinemic amenorrhea

To examine the role of melatonin in pathological hyperprolactinemia we compared untreated young females (N = 5) with hyperprolactinemic amenorrhea owing to pituitary microadenoma to healthy female controls (N = 6). Serum samples for melatonin, prolactin, and luteinizing hormone (LH) concentrations were obtained every 15 min from 1900 hr to 0700 hr in a controlled light-dark environment with simultaneous sleep recordings. The mean (+/- SD) light-time period, dark-time period, and the integrated nocturnal melatonin secretion values (area under the curve, or AUC) in patients (51 +/- 11 pmol/L, 157 +/- 33 pmol/L, and 102 +/- 19 pmol/min.L x 10(3), respectively) were similar to the values obtained in controls (79 +/- 39, 165 +/- 44, 111 +/- 31, respectively). The onset of the nocturnal melatonin rise, peak level, and peak time were similar in the two groups. A significant nocturnal prolactin rise was observed in patients (112 +/- 9 vs. 65 +/- 11 micrograms/L, P < 0.006) and controls (19 +/- 2 vs. 10 +/- 3 micrograms/L, P < 0.006). The time of prolactin peak was similar in patients and controls (0424 +/- 3:36 vs. 0350 +/- 2:21) and paralleled that of melatonin (0354 +/- 1:46 vs. 0337 +/- 1:30). The mean +/- SD light-time period, dark-time period, and the AUC values of LH were similar in patients and controls. The number of LH pulses in patients (7.2 +/- 1.9 per 12 hr) were not different from those in controls (7.7 +/- 2.1). The LH pulse interval was 100 +/- 22 min in patients compared with 94 +/- 23 min in controls. The mean (+/- SD) nocturnal estradiol (E2) levels were significantly lower in patients (84 +/- 15 pmol/L) than in controls (224 +/- 77) (P < 0.005). Analysis of LH and melatonin secretory profiles revealed significant pulses for both hormones. No significant relationship was observed between the LH and melatonin pulses. However, a negative correlation between LH pulse amplitude and the number of melatonin pulses (P < 0.04) and a positive correlation between LH amplitude and duration of melatonin pulses (P < 0.04) were observed. Taken together, these data suggest that the suppression of normal ovarian cycles in women with hyperprolactinemic amenorrhea owing to pituitary microadenoma may be mediated by blocking of gonadotropin action by prolactin at the ovarian level; yet it remains possible that chronically elevated prolactin might prevent the LH surge and thus lead to amenorrhea. Pulsatile melatonin secretion is unaltered in these patients, and frequent occurrence of amenorrhea in this population is not mediated by melatonin.

Testosterone treatment alters melatonin concentrations in male patients with gonadotropin-releasing hormone deficiency

Recently, we demonstrated that melatonin secretion is increased in untreated male patients with GnRH deficiency. As testosterone (T) can be aromatized to estradiol (E2), and both T and E2 increase during T enanthate treatment, we were interested in determining whether T treatment (when T and E2 levels were well matched with pubertal control values) has an effect on melatonin levels in these patients. We measured nocturnal serum melatonin levels during the administration of 250 mg testosterone enantale/month for 4 months in 12 male patients with idiopathic hypogonadotropic hypogonadism (IGD; n = 6) and delayed puberty (DP; n = 6). Serum samples for melatonin and LH determinations were obtained every 15 min from 1900-0700 h in a controlled light-dark environment. The results of melatonin profiles were compared with the pretreatment values in each group and with values obtained in six normal pubertal male controls. After 4 months of testosterone treatment, all patients attained normal serum testosterone (19.5 +/- 3.7 in IGD vs. 20.8 +/- 4.1 nmol/L in DP) and E2 levels (83 +/- 12 in IGD vs. 84 +/- 9 pmol/L in DP). Serum LH levels were suppressed in all patients during T treatment (0.12 +/- 0.1 in IGD vs. 0.12 +/- 0.2 IU/L in DP). Before T treatment, patient melatonin levels were greater than those in age-matched pubertal controls. Melatonin levels were equal in patients and controls when T and E2 levels were well matched. Mean (+/- SD) dark-time melatonin levels decreased from 286 +/- 23 to 157 +/- 36 pmol/L in IGD and from 217 +/- 32 to 133 +/- 47 pmol/L in DP (vs. 183 +/- 64 pmol/L in controls). The integrated melatonin values decreased to normal (from 184 +/- 16 to 102 +/- 21 in IGD and from 142 +/- 19 to 90 +/- 26 pmol/min.L x 10(3) in DP vs. 119 +/- 61 pmol/min.L x 10(3) in controls). The intraindividual variations in melatonin levels ranged from 7.2-14.5%. These data indicate that male patients with GnRH deficiency have increased nocturnal melatonin secretion. T treatment decreased melatonin secretion to normal levels. The results suggest that in GnRH-deficient male patients, sex steroids, rather than LH, modulate pineal melatonin in a reverse fashion.

Melatonin replacement corrects sleep disturbances in a child with pineal tumor

A child with a germ cell tumor involving the pineal region had marked suppression of melatonin secretion associated with severe insomnia. Exogenous melatonin (3 mg in the evening) for 2 weeks restored sleep continuity, as demonstrated by objective monitoring of rest-activity cycles. This case report provides direct evidence of the essential role of melatonin in normal sleep.

Prevalence of cognitive dysfunction and hypothyroidism in an elderly community population

Cognitive function was assessed in 801 elderly subjects (aged 65-92 years) using the Mini Mental State Examination (MMSE). The mean (+/- SD) MMSE score in the age group 65-70 years was 27.8 +/- 5.6, and the score declined to 22.3 +/- 7.8 at the age 85-90 (P = 0.001). Abnormal MMSE scores (less than 24) were found in 5.2% of the subjects aged 65-70 and gradually increased with age to 35.5% in the age group of 85-90. Serum thyroid-stimulating hormone (TSH) levels were determined in 751 subjects. Elevated TSH (> 4.5 mIU/l) were detected in 112 people (14%). The prevalence of hypothyroidism was higher in females (18.2%) than in males (9.7%). MMSE scores in 39 patients (14 males and 25 females) with untreated hypothyroidism were compared to the scores of 570 euthyroid elderly controls (235 males and 335 females). The mean +/- SD MMSE scores were 27.0 +/- 2.1 in hypothyroid males vs. 26.0 +/- 4.7 in male controls and 25.0 +/- 7.7 in hypothyroid females vs. 25.0 +/- 6.6 in female controls. The scores in the hypothyroid patients were not significantly different from the controls. Our data suggest that: a) the average cognitive performance declines with age; b) the percentage of subjects with abnormal MMSE scores increases with age, and is higher in females than in males; c) the prevalence of hypothyroidism in the elderly population is 14% and is higher in females (18%) than in males (10%); and d) mild untreated hypothyroidism is not associated with cognitive impairment.

Pseudo-precocious puberty in a male patient and the melatonin-testosterone relationship

We describe a 14 year-old boy with a pineal germ cell tumor which secreted beta HCG. Serum testosterone levels were markedly elevated with concomitant decreased LH secretion. 24-h serum melatonin levels were suppressed and lacked the normal nocturnal rise. Pineal radiation therapy was followed by tumor regression and the diminution of beta HCG stimulated testosterone, which in turn inhibited melatonin and LH. When beta HCG and testosterone were normalized after tumor radiation, a recovery of normal melatonin and LH secretory pattern occurred. These results indicate that circulating testosterone down-regulates pineal melatonin.

Increased nocturnal melatonin secretion in male patients with hypogonadotropic hypogonadism and delayed puberty

Hypogonadotropic hypogonadism (IGD) and constitutional delayed puberty (DP) share a common pathophysiologic process, i.e. GnRH deficiency. Both conditions are heterogenous and exhibit different grades of GnRH deficiency. To discern whether these disorders of GnRH deficiency are associated with altered melatonin secretion profiles, we compared untreated young males IGD (n = 7) and DP (n = 7) to normal pubertal male controls (n = 6). Serum samples for melatonin, LH, and prolactin concentrations were obtained every 15 min from 1900 h to 0700 h in a controlled light-dark environment with simultaneous sleep recordings. Mean (+/- SD) darktime nocturnal melatonin levels were significantly higher in IGD (259 +/- 73 pmol/L) and DP (217 +/- 29 pmol/L) compared with 182 +/- 69 pmol/L in controls (P < 0.02). So were the mean (+/- SD) peak melatonin levels (410 +/- 117, 327 +/- 97 and 298 +/- 95 pmol/L in IGD, DP, and controls, respectively (P < 0.05). Integrated nocturnal melatonin secretion values (AUC) were also higher in IGD and DP (168 +/- 45 and 134 +/- 28) compared with 119 +/- 45 pmol/min.1 x 10(3) in controls (P < 0.02). The time of melatonin peak and the time of onset of the nocturnal melatonin rise were observed earlier in IGD and DP. Light-time mean (+/- SD) serum melatonin levels were similar in all three groups. No correlations were found between melatonin and LH levels, nor between melatonin and prolactin levels. These data indicate that melatonin secretion is increased in male patients with GnRH deficiency. The lack of correlations between melatonin and LH suggest that circulating sex steroids, rather than LH, modulate melatonin secretion in a reverse fashion.

Syncytial variant of nodular sclerosing Hodgkin's disease presenting as a thyroid nodule. A case report

The fine needle aspiration cytology of a thyroid nodule in a 19-year-old female showed Reed-Sternberg (RS) cell variants in clusters, thereby suggesting the possibility of syncytial variant of nodular sclerosing Hodgkin's disease (NSHD). A similar picture was observed on imprint smears of an excised cervical lymph node, the histology of which confirmed the original diagnosis. Following chemotherapy, the nodule disappeared. The patient was spared major thyroid surgery. It is important to recognize the rare morphologic variants and unusual clinical presentations of common diseases in order to perform appropriate studies that will ensure that the patient receives the best clinical management. Morphologic clues that should arouse the cytopathologist's awareness of this rare variant of NSHD are presented.

[Prevalence of diabetes mellitus and glucose intolerance in adult Ethiopian immigrants]

339 adult immigrants from Ethiopia were surveyed 1 year after arrival. They were screened for diabetes mellitus and impaired glucose tolerance by measurement of serum HgbA1C levels. The levels were higher than normal in 35 subjects (10.3%), and were significantly higher in immigrants consuming the Israeli diet, which is richer in proteins and carbohydrates, than in those on the Ethiopian diet. Oral glucose load was abnormal in 7 subjects. 3 had overt diabetes mellitus with absent serum insulin response to glucose load. 4 had glucose intolerance with normal insulin secretion. However, clinical appearance of diabetes was incidental and diabetes ketoacidosis was not detected. The overall prevalence of diabetes mellitus and glucose intolerance in this ethnic group (2.1%) is similar to that in the general population of Israel. Longitudinal studies would indicate the exact prevalence and type of diabetes mellitus among the Ethiopian immigrants.

Goiter prevalence in children immigrating from an endemic goiter area in Ethiopia to Israel

A survey study was performed to assess the prevalence of goiter and thyroid dysfunction in a population of 534 Ethiopian children, one year after arrival in Israel. The overall prevalence of goiter was 43.6%. Children in the age group 1-2 years had the lowest prevalence of goiter (6.7%). A progressive increase in goiter prevalence and size with age was observed, with peak occurrence around puberty for both boys (56.7%) and girls (72.2%). Serum FT4 levels were elevated in 4 children; elevated serum TSH levels (above 4.5 mIU/l) were found in 11 children, all of them had normal FT4 levels. Thus the prevalence of hypothyroidism and hyperthyroidism was 2% and 0.8%, respectively, with an even distribution across the various age groups. All the children were clinically normal. The high prevalence of goiter in this group of Ethiopian children with the low frequency of hypothyroidism may be attributed to the combined effects of food goitrogens and iodine deficiency prevailing in Ethiopia. The standard Israeli diet seems to be adequate in respect to iodine requirements, and no iodine enrichment is needed for children immigrating from Ethiopia.

High prevalence of vitamin D deficiency among Ethiopian women immigrants to Israel: exacerbation during pregnancy and lactation

A population of 125 adult Ethiopian women immigrants to Israel was screened for serum levels of calcium, phosphorus, and alkaline phosphatase. Five women (prevalence of 4%) had hypocalcemia and in one of them osteomalacia was found. In the other 120 subjects normal values were recorded. All five patients had low serum levels of 25 hydroxy (OH) vitamin D3 and high parathyroid hormone (PTH) levels. In four of the five patients, clinical and biochemical manifestations of vitamin D deficiency were detected during pregnancy or lactation. Treatment with vitamin D2 for 4-13 months resulted in clinical improvement and partially corrected the biochemical abnormalities, but low serum vitamin D levels and elevated PTH levels persisted. We conclude that vitamin D deficiency among female Ethiopian immigrants to Israel can be ascribed either to dark skin or low calcium and vitamin D intake, or both. As far as we known this is the first report of vitamin D deficiency among such immigrants. Our study suggests the need to be alert to the possibility of vitamin D deficiency in Ethiopian women who have immigrated to Israel, in particular those who are pregnant or are breast-feeding.

[Calcitonin nasal spray for Paget's disease of the bone]

3 patients with prolonged, diffuse, bone pain due to Paget's disease were treated with intranasal salmon calcitonin, 200-400 U/d for 12 months. Within the first 3 months, in all 3 bone turnover decreased 31-35% (as assessed by serum alkaline phosphatase activity and urinary hydroxyproline/creatinine ratio). After 1 year of nasal calcitonin the reduction in serum alkaline phosphatase was 24%, and in urinary hydroxyproline 10%. In addition, pain and functional impairment markedly improved during the year. It is concluded that daily nasal calcitonin spray is well tolerated and effective initial treatment for Paget's disease of the bone.