Association of serum testosterone levels and testicular volume in adult patients.

A retrospective observational study was undertaken to gain new insight into the relationship between total testicular volume and levels of serum testosterone, luteinising hormone, follicle-stimulating hormone, prolactin and clinical variables. A total of 312 men with sexual dysfunction or infertility were divided into groups A and B (156 each) on the basis of basal plasma testosterone ≤5 nmol/L of ≥12 nmol/L respectively. Group A was subclassified in A1 (primary hypogonadism) and A2 (secondary hypogonadism). There were significant differences in total testicular volume between group A (15.33 ± 11.94 ml) and group B (36.74 ± 6.9; p < .001) and also between subgroup A1 (11.07 ± 8.49 ml) and subgroup A2 (23.62 ± 13.04 ml; p < .001). Only 13.5% of patients in group B had a total testicular volume <30 ml. Differences in all studied parameters were found between group A and group B. There were no variations when comparing age, body mass index and testosterone in groups A1 and A2 . The use of total testicular volume and body mass index together for predicting testosterone levels yields a sensitivity and specificity of 85.3% and 86.5% respectively. Logistic regression analysis, univariate and multivariate models, using the measurement of total testicular volume resulted in a high capacity to predict testosterone levels.

Metabolic syndrome in Mediterranean women with polycystic ovary syndrome: when and how to predict its onset.

Polycystic ovary syndrome (PCOS) is associated with the metabolic syndrome (MetS). The metabolic disorders are not universal and may vary with race, age and phenotype. Our purpose was to determine the clinical and biochemical characteristics of Mediterranean PCOS women with MetS, compare them with non-MetS PCOS patients, and assess the ability of clinical data and biochemical tests to predict these abnormalities within our population. A total of 218 subjects, 196 PCOS women and 22 controls, undergo a physical examination and laboratory evaluation for a diagnosis of MetS. MetS was categorized according to NCEP ATP III guidelines. PCOS patients were analyzed separately and compared in three subgroups: three or more MetS criteria, two criteria, one or no criteria. The overall prevalence of MetS was 21.4%. Women with MetS had higher glucose (G) levels than PCOS women with two criteria (5.7 ± 1.5 vs 5 ± 0.4, p < 0.05). Both groups were comparable for all the other parameters. Waist circumference (WC), body mass index (BMI), systolic (SBP) and diastolic blood pressure (DBP), bioavailable testosterone (uT), triglycerides (TG) and insulin (I) levels were significantly higher and sex hormone-binding globulin (SHBG) levels, high-density lipoprotein (HDL), HOMA and QUICKI indexes significantly lower in both groups, MetS and patients with two criteria, compared with women with one or no criteria and the control group. WC, HDL and TG were the best predictors of PCOS patients at risk for MetS. In conclusion, we recommend considering PCOS patients with two criteria of MetS as having the same risk as patients with the full syndrome. Waist circumference with HDL and triglycerides is an efficient combined test to identify PCOS women at risk for metabolic and cardiovascular diseases.

Asociación de la rigidez peneana nocturna con testosterona, síndrome metabólico y otras variables: un estudio piloto prospectivo transversal / Association of Nocturnal Penile Rigidity with Testosterone, Metabolic Syndrome, and Other Variables: a Prospective Cross-Sectional Pilot Study

Introducción: El objetivo fue estudiar la relación entre la rigidez peneana nocturna (RPN) con el síndrome metabólico (SM) y la testosterona en varones que consultan por trastornos de erección (DE). Material y método: Se incluyeron 234 varones en un estudio piloto prospectivo y transversal. Se midieron los niveles séricos de testosterona total y biodisponible y otros parámetros bioquímicos relacionados con el SM y con las RPN. Los pacientes se agruparon según la rigidez de las erecciones: normales (alta rigidez, componente predominante psicológico de la disfunción) o anormales (baja rigidez, posible componente orgánico o físico de la DE) y por la presencia o ausencia de SM. Resultados: El modelo de regresión logística para la rigidez del pene como variable dependiente demostró que el riesgo de rigidez anormal es menor en individuos con mayor testosterona total (OR=0,96; 95% CI=0,92-0,99) o biodisponible (OR=0,91; 95% CI=0,84-0,99). Pacientes con niveles de testosterona entre 8 y 12 mmol/L presentaron un riesgo cuatro veces mayor de tener rigidez anormal comparados con aquellos con niveles superiores a 12 mmol/L (OR=3,96; 95% CI=1,89, 8,31). Si se consideraban únicamente aquellos varones sin SM, solo la edad y el índice de masa corporal (IMC) aparecían como factores de riesgo asociados a la rigidez anormal. La edad aumentó el riesgo de rigidez anormal en un 8% (OR=1,08; 95% CI=1,03-1,13) y el IMC lo aumentó en un 18% (OR=1,18; 95% CI=1,01-1,38). Conclusión: La asociación de niveles de testosterona con la rigidez del pene fue baja y desaparece si se asocia con SM (AU)

Introduction: The aim was to study whether nocturnal penile rigidity (NPTR) correlates with metabolic syndrome (MetS) and testosterone in men consulting for erectile dysfunction (ED). Material and methods: 234 men were included in a prospective, cross-sectional pilot study. Serum total and bioavailable testosterone and other biochemical constituents were measured and compared with NPTR. Patients were classified by normal or low/abnormal penile rigidity (abnormal meaning predominant organic component of ED) and presence or absence of MetS to test the hypothesized correlations. Results: Application of the logistic regression model to rigidity as the dependent variable showed the risk of low penile rigidity to be significantly lower for patients with higher total (OR=0.96, 95% CI=0.92-0.99) or bioavailable testosterone (OR=0.91, 95% CI=0.84-0.99). Patients with testosterone levels between 8 and 12 mmol/L had a quadrupled risk of low penile rigidity compared with patients with higher levels (>12 mmol/L) (OR=3.96, 95% CI=1.89-8.31). Considering men without MetS, age and body mass index were associated as significant factors for low penile rigidity: age increased risk by 8% (OR=1.08, 95% CI=1.03-1.13) and BMI increased it by 18% (OR=1.18, 95% CI=1.01-1.38). Conclusion: Testosterone levels are weakly associated with penile rigidity and disappear when associated with MetS (AU)

[Association of nocturnal penile rigidity with testosterone, metabolic syndrome, and other variables: a prospective cross-sectional pilot study]. / Asociación de la rigidez peneana nocturna con testosterona, síndrome metabólico y otras variables: un estudio piloto prospectivo transversal.

INTRODUCTION: The aim was to study whether nocturnal penile rigidity (NPTR) correlates with metabolic syndrome (MetS) and testosterone in men consulting for erectile dysfunction (ED). MATERIAL AND METHODS: 234 men were included in a prospective, cross-sectional pilot study. Serum total and bioavailable testosterone and other biochemical constituents were measured and compared with NPTR. Patients were classified by normal or low/abnormal penile rigidity (abnormal meaning predominant organic component of ED) and presence or absence of MetS to test the hypothesized correlations. RESULTS: Application of the logistic regression model to rigidity as the dependent variable showed the risk of low penile rigidity to be significantly lower for patients with higher total (OR=0.96, 95% CI=0.92-0.99) or bioavailable testosterone (OR=0.91, 95% CI=0.84-0.99). Patients with testosterone levels between 8 and 12 mmol/L had a quadrupled risk of low penile rigidity compared with patients with higher levels (>12 mmol/L) (OR=3.96, 95% CI=1.89-8.31). Considering men without MetS, age and body mass index were associated as significant factors for low penile rigidity: age increased risk by 8% (OR=1.08, 95% CI=1.03-1.13) and BMI increased it by 18% (OR=1.18, 95% CI=1.01-1.38). CONCLUSION: Testosterone levels are weakly associated with penile rigidity and disappear when associated with MetS.

Prevalence of metabolic syndrome among human immunodeficiency virus-infected subjects is widely influenced by the diagnostic criteria.

BACKGROUND: The aim of this study was to compare the prevalence of metabolic syndrome in human immunodeficiency virus (HIV)-infected patients treated with highly active antiretroviral therapy (HAART), using the National Cholesterol Education Program Adult Treatment Panel III (NCEP ATP III), European Group for the Study of Insulin Resistance (EGIR), and International Diabetes Federation (IDF) definitions. METHODS: A cross-sectional study was carried out with 159 consecutive adult HIV-infected subjects (120 males and 39 females) under HAART. Anthropometric and laboratory parameters were measured by standard methods. Hyperinsulinemia was defined by a fasting concentration >75th percentile of values obtained in healthy individuals (107.5 pmol/L). RESULTS: The prevalence of ATP III-defined metabolic syndrome was 10.1%; it was 28.3% according to EGIR criteria and 15.1% using the IDF definition. The concordance between the definitions was low (kappa coefficient ranging between 0.134 and 0.296). All subjects with EGIR-defined metabolic syndrome had hyperinsulinemia, but only 50% of those with ATP III-defined metabolic syndrome and 62.5% in the IDF metabolic syndrome population had hyperinsulinemia. CONCLUSIONS: The inclusion of hyperinsulinemia as a criterion in the EGIR metabolic syndrome definition made it more discriminative than the ATP III definition, both in men and women, and than the IDF definition in men to identify metabolic syndrome in HIV-infected subjects under HAART.

Macroprolactinemia en un paciente con un tumor germinal. Una entidad que tener en cuenta en pacientes con hiperprolactinemia / Macroprolactinemia in a male patient with germ cell tumor. A condition to be considered in patients with hyperprolactinemia

La hiperprolactinemia puede deberse a causas fisiológicas, patológicas y farmacológicas. A pesar de exámenes clínicos, hormonales y radiológicos exhaustivos, algunos pacientes pueden presentar una concentración de prolactina (PRL) elevada sin una etiología clara. Muchos de los casos de hiperprolactinemia idiopática se deben a la presencia en suero de una PRL no funcionante de elevada masa molecular. Se describe esta entidad, conocida como macroprolactinemia, a partir de un caso clínico de un paciente afecto de un tumor germinal. A pesar de tener hiperprolactinemia, muchos pacientes se encuentran asintomáticos y no requieren tratamiento. La macroprolactinemia debe sospecharse para evitar exploraciones y tratamientos innecesarios (AU)

Hyperprolactinemia may be due to physiological, pathological and pharmacological causes. Despite exhaustive clinical, hormonal and radiological examinations, some patients may have a high concentration of prolactin with no clear etiology. Many cases of idiopathic hyperprolactinemia are due to the presence of a non-functioning serum prolactin of high molecular weight. We describe this condition, known as macroprolactinemia, using a case of a patient with a germinal tumor. Because most patients with macroprolactinemia are symptom- free despite hyperprolactinemia and drug therapy would not be indicated, macroprolactinemia should be suspected to avoid unnecessary examinations and treatments (AU)

Long-lasting subclinical Addison's disease.

OBJECTIVE: To report a patient with autoimmune adrenal disease and increased ACTH with longstanding hyperpigmentation as an isolated symptom. METHODS: A 49-year-old woman requested a diagnostic work-up for hyperpigmentation initiated 9 years before, associated with increased ACTH. She was receiving replacement therapy for autoimmune hypothyroidism. Basal and dynamic tests of glucocorticoid axis, basal investigation of mineralocorticoid axis and measurement of organ specific autoantibodies were performed. RESULTS: Plasma ACTH (143 pmol/l; normal <13.2 pmol/l) and antibodies against 21-hydroxylase (115 UI/ml; normal <1) were remarkably high, thyroid peroxidase and parietal cell antibodies were positive at low titer and all additional tests were normal. CONCLUSION: Autoimmune adrenal disease can have a very long preclinical period even with high concomitant ACTH and specific antibody titers.

Disfunción tiroidea en mujeres con sospecha de fibromialgia / Thyroid dysfunction in women with suspected fibromyalgia

Fundamento y objetivo: La fibromialgia (FM), por su prevalencia, morbilidad y tasa de frecuentación, representa un problema de salud y genera un elevado consumo de recursos sanitarios. La medida de tirotropina (TSH) en el suero se recomienda como prueba complementaria de primera línea para descartar hipotiroidismo como anomalía simuladora de la enfermedad. El objetivo fue analizar, en mujeres con sospecha de FM, la prevalencia de disfunción tiroidea (DT), la frecuencia de solicitud analítica de tirotropina, el efecto del tratamiento con levotiroxina y si se justifica o no el escrutinio de DT. Pacientes y métodos: Estudio descriptivo transversal. Desde enero de 2001 a octubre de 2004 se estudió a 400 mujeres consecutivas con sospecha de FM y a 384 controles. La medida de tirotropina se usó como primera prueba para detectar DT. Resultados: La prevalencia de DT en la sospecha de FM (40/400; 10%, intervalo de confianza [IC] del 95%, 7-13%) no difirió de la de controles (46/384; 12%, IC del 95%, 9-15%); tampoco al comparar distintos tipos y grados de DT. En la sospecha de FM, la DT fue más prevalente (p = 0,001) en portadoras (12%) que en no portadoras (5%) de enfermedad del tejido conectivo. La DT más frecuente fue el hipotiroidismo subclínico (5,5% en FM y 6,7% en controles), y en el 93% de casos nuevos la concentración de TSH fue < 10 mUI/l. La FM persistió en todas las pacientes hipotiroideas al lograrse el eutiroidismo. En 360 pacientes eutiroideas con sospecha de FM se realizaron 870 determinaciones de TSH. Conclusiones: En mujeres con sospecha de FM, la prevalencia de DT no difiere de la descrita en la población general, no parece justificarse el escrutinio de DT en no portadoras de enfermedad de riesgo y la demanda analítica es en muchos casos excesiva; el tratamiento del hipotiroidismo no influye en la FM(AU)

Background and objective: Due to its prevalence, morbidity, and frequency rate, fibromyalgia (FM) represents a health problem and produces high healthcare resource utilization. Serum thyrotropin (TSH) measurement is recommended as a first-line laboratory test to exclude hypothyroidism as a cause of FM syndrome. The aim of this study was to analyze the prevalence of thyroid dysfunction (TD), the frequency of TSH measurement, the effect of levothyroxine treatment, and whether screening for TD is justified in women with suspected FM. Patients and methods: A cross-sectional descriptive study was performed in 400 consecutive female outpatients with suspected FM and in 384 controls from January 2001 to October 2004. TSH measurement was used as the first line test to detect TD. Results: The prevalence of TD in patients with suspected FM (40/400; 10%; 95% CI: 7-13%) and controls was similar (46/384; 12%; 95% CI: 9-15%). No differences were found in the types and grades of TD. The prevalence of TD was higher in patients with suspected FM and connective tissue diseases (12%) than in those without these diseases (5%). The most frequent TD was subclinical hypothyroidism (5.5% in suspected FM and 6.7% in controls), and in 93% of these cases TSH concentrations were <10 mIU/L. FM persisted in all women with hypothyroidism even after euthyroidism was achieved with levothyroxine. A total of 870 TSH determinations were performed in 360 euthyroid patients with suspected FM. Conclusions: The prevalence of TD in women with suspected FM does not differ from that in the general population. Screening for TD does not appear to be justified in women without diseases that increase their risk. In many cases the request for thyroid function tests is excessive. Treatment for hypothyroidism does notaffect FM(AU)

[Thyroid dysfunction in women with suspected fibromyalgia]. / Disfunción tiroidea en mujeres con sospecha de fibromialgia.

BACKGROUND AND OBJECTIVE: Due to its prevalence, morbidity, and frequency rate, fibromyalgia (FM) represents a health problem and produces high healthcare resource utilization. Serum thyrotropin (TSH) measurement is recommended as a first-line laboratory test to exclude hypothyroidism as a cause of FM syndrome. The aim of this study was to analyze the prevalence of thyroid dysfunction (TD), the frequency of TSH measurement, the effect of levothyroxine treatment, and whether screening for TD is justified in women with suspected FM. PATIENTS AND METHODS: A cross-sectional descriptive study was performed in 400 consecutive female outpatients with suspected FM and in 384 controls from January 2001 to October 2004. TSH measurement was used as the first line test to detect TD. RESULTS: The prevalence of TD in patients with suspected FM (40/400; 10%; 95% CI: 7-13%) and controls was similar (46/384; 12%; 95% CI: 9-15%). No differences were found in the types and grades of TD. The prevalence of TD was higher in patients with suspected FM and connective tissue diseases (12%) than in those without these diseases (5%). The most frequent TD was subclinical hypothyroidism (5.5% in suspected FM and 6.7% in controls), and in 93% of these cases TSH concentrations were <10 mIU/L. FM persisted in all women with hypothyroidism even after euthyroidism was achieved with levothyroxine. A total of 870 TSH determinations were performed in 360 euthyroid patients with suspected FM. CONCLUSIONS: The prevalence of TD in women with suspected FM does not differ from that in the general population. Screening for TD does not appear to be justified in women without diseases that increase their risk. In many cases the request for thyroid function tests is excessive. Treatment for hypothyroidism does not affect FM.

Influence of exogenous insulin on C-peptide levels in subjects with type 2 diabetes.

AIM: The aim of this study was to determine whether the influence of insulin therapy on fasting and stimulated C-peptide levels in type 2 diabetic subjects is due to plasma glucose reduction or a direct effect of exogenous insulin. METHODS: Plasma glucose and serum C-peptide levels were determined before and after IV injection of 1mg glucagon on three separate days in 21 type 2 diabetic subjects. Day 1: without pharmacological treatment and fasting plasma glucose > 11.1 mmol/L; day 2: fasting plasma glucose 4.4-7.8 mmol/L, 1h after withdrawing intravenous regular insulin infusion; day 3: fasting plasma glucose 4.4-7.8 mmol/L with bed-time NPH insulin. RESULTS: Fasting and glucagon stimulated C-peptide levels were higher on day 1 than days 2 and 3. Fasting, but not stimulated C-peptide levels, were lower on day 3 than day 2. These differences were not appeared when the percentage of C-peptide increment or the C-peptide/glucose ratio were compared in the three days. CONCLUSIONS: Blood glucose reduction instead of exogenous insulin is responsible for the C-peptide decrease during insulin therapy in type 2 diabetic subjects.

Emerging cardiovascular risk factors in subclinical hypothyroidism: lack of change after restoration of euthyroidism.

Subclinical hypothyroidism (SH) is a frequent condition that may be associated with increased cardiovascular risk. There is current interest in determining the effect, if any, of substitutive therapy with l-thyroxine (L-T4) on cardiovascular risk factors in SH and, particularly, on those associated with emerging cardiovacular risk, such as apolipoprotein (apo) B, lipoprotein (Lp) (a), total homocysteine (t-Hcy), and C-reactive protein (CRP). Thus, the aim of this study was to assess the impact of euthyroidism restoration on these emerging risk factors in SH. Forty-two patients diagnosed with SH were consecutively recruited before treatment. These patients were treated with L-T4 for 3 to 6 months with the dose necessary to restore euthyroidism. Lp(a), fasting and postmethionine (n = 28) t-Hcy, and CRP did not change with substitutive therapy, regardless of the respective baseline values, and the decrease in apo B paralleled that of low-density lipoprotein (LDL) cholesterol. Similarly, no treatment effect was observed on homocysteine or CRP in patients with thyrotropin-stimulating hormone (TSH) >10 mIU/L. Monitoring of emerging risk factors did not offer additional arguments for treating patients with SH and, thus, is not justified in their clinical management.

Problemas de la determinación de tiroglobulina / The challenge of thyroglobulin resistance

La medida de la concentración de tiroglobulina en el suero es útil en el diagnóstico y seguimiento de diversas anomalías tiroideas, sobre todo como marcador tumoral en el cáncer diferenciado de tiroides. Sin embargo, a pesar del espectacular desarrollo experimentado por el inmunoanálisis de dicha magnitud en los últimos 30 años, todavía existen serios problemas, tanto dependientes como independientes del método, que hacen de esta determinación uno de los mayores desafíos para el laboratorio clínico, principalmente cuando se trata de usarla para identificar pacientes con residuo o recidiva tumoral. En esta revisión se destacan y analizan los principales factores que dificultan la medida de dicha magnitud y se describen los procedimientos y medios disponibles para soslayarlos o, al menos, minimizarlos (AU)

El uso de marcadores de recambio óseo en la práctica clínica: entre la realidad y el deseo / the use of bone turnover markers in clinical practice: between reality and desire

No disponible

Thyroglobulin autoantibody levels below the cut-off for positivity can interfere with thyroglobulin measurement.

Antithyroglobulin antibodies can interfere with the measurement of thyroglobulin yielding spuriously high or low levels depending on the method used. Interference is unrelated to the antibody concentration and can occur at very low concentrations. We report a patient in whom antithyroglobulin antibodies below the cut-off for positivity nearly led to an incorrect diagnosis of thyrotoxicosis factitia.

Effect of cholecystokinin-A receptor blockade on postprandial insulinaemia and gastric emptying in humans.

Our aim was determine the relationship between cholecystokinin (CCK)-A receptor blockade, glucose levels, insulin secretion and gastric emptying in humans, and to assess the effect of CCK-A blockade on pancreatic polypeptide secretion. After a 12-h fast, six healthy volunteers were given [99mTc]iminodiacetic acid monosodium salt (IDA) intravenously (5 mCi). One hour later they were offered a 577 kcal liquid meal containing [99mTc]diethylenetriaminepentaacetic acid (DTPA) (2 mCi) and glucose (105 g). Scintigraphic gastric and gallbladder activity, and plasma glucose, insulin and pancreatic polypeptide responses were monitored. In a second experiment, a continuous intravenous infusion of loxiglumide (7.5 mg kg h(-1)) was started 60 min before and continued until 120 min after test meal ingestion to block the CCK-A receptors. Gallbladder emptying was blocked by loxiglumide. Loxiglumide accelerated gastric emptying, increased insulin secretion without alteration of glucose profiles, and abolished all phases of the postprandial pancreatic polypeptide response. Blockade of peripheral CCK-A receptors accelerates gastric emptying of liquids with an increase in postprandial insulin levels. The lack of changes in glycaemia suggests that alternative homeostatic mechanisms also control postprandial glucose levels. Inhibition of pancreatic polypeptide release may reflect an independent effect of loxiglumide on vagal control involved in pancreatic polypeptide release.

Hiperprolactinemia por macroprolactina y disfunción eréctil / Hyperprolactinemia due to macroprolactin and erectile dysfunction

Se describe el caso de un varón de 61 años asistido por disfunción eréctil asociada a hiperprolactinemia. Las imágenes hipofisarias obtenidas por RMN y TAC fueron normales, y los tratamientos llevados a cabo con agonistas dopaminérgicos no mejoraron la función eréctil, aunque normalizaron las concentraciones de prolactina. A pesar de la persistencia de hiperprolactinemia, el paciente recuperó espontáneamente su función eréctil al resolverse de manera favorable sus problemas de relación con su pareja sexual. La causa de la hiperprolactinemia se encontró posteriormente al demostrar, mediante cromatografía de filtración en gel, que la forma mayoritaria de prolactina en el suero del enfermo (62-66 por ciento) correspondía a macroprolactina, especie molecular desprovista de actividad biológica in vivo. Este hallazgo condujo al diagnóstico final de disfunción eréctil psicógena. La macroprolactinemia confundió y retrasó el diagnóstico correcto, promovió la realización de exploraciones costosas e indujo tratamientos innecesarios. Casos como éste apoyan la utilidad del escrutinio de macroprolactinemia entre los pacientes con hiperprolactinemia, sobre todo en aquellos cuyos datos bioquímicos no se corresponden claramente con los clínicos (AU)

Decreased insulin requirements after LAR-octreotide but not after lanreotide in an acromegalic patient.

A diabetic acromegalic man, not cured after surgery and radiosurgery, received lanreotide i.m. with great clinical and biochemical improvement. He required NPH insulin (76 to 84 units/day) to control his diabetes mellitus. Thirty-six hours after changing to LAR-octreotide (20 mg i.m/month) he presented symptomatic hypoglycemia, repeated at 48 and 72 h (50 mg/dL), despite reducing insulin to 26 Units/day. Thereafter, he reduced insulin by 30 to 50% for the first week after each LAR-octreotide injection, and gradually increased it again over the next 3 weeks. This situation persists after every injection 3 years later; this consistent behavior supports a specific effect of LAR-octreotide, and not a by chance phenomenon. No marked changes in circulating GH, IGF-1, immunoreative insulin, C-peptide, testosterone and glucose were observed prior to, and 3, 7, 14, 21, and 28 days after LAR-octreotide; however, there was 28% fall in plasma glucagon after 7 days, which rose thereafter. C-peptide (< 1.8 ng/mL) was indicative of decreased beta-cell function. To our knowledge, this is the first report of such a distinct differential behaviour of blood glucose and insulin requirements with different somatostatin analogs, and is worth recalling when starting an insulin-treated diabetic patient on this treatment. It may be related to a preferential binding of LAR-octreotide to subtype 2 somatostatin receptors in the pancreas, while lanreotide preferentially binds to subtype 5, not expressed in this tissue; this would explain the fall in glucagon, in parallel to the decrease in insulin requirements after LAR-octreotide; however, a contribution of differences in the effect of both somatostatin analogues on postreceptor signalling systems and/or intestinal carbohydrate absorption cannot be entirely ruled out.

Transient pituitary hypothyroidism in a patient with ectopic adrenocorticotrophic hormone secretion.

We report the case of a 55-year-old woman who presented with hypercortisolism secondary to ectopic adrenocorticotrophic hormone secretion and severe non-thyroidal illness syndrome (NTIS) due to metastatic small cell lung carcinoma associated with severe infections. The patient initially showed hormonal profiles of pituitary hypothyroidism and gonadal hypofunction. After decrease in cortisol production following treatment with chemotherapy and metyrapone, serum thyroid hormones and thyroid-stimulating hormone (TSH) concentrations normalized. Study of the relative contributions of cortisol and pro-inflammatory cytokines (interleukin-6 and tumour necrosis factor alpha) to the overall variability in thyroid function tests disclosed a significant and independent effect of serum cortisol on serum TSH concentrations; the variability in free thyroid hormone concentration was explained only by changes in TSH concentration. These observations indicate that cortisol could be the major determinant of changes in serum TSH concentrations in clinical conditions accompanied by hypercortisolism, as occurs in NTIS.