Angela Termine

The corticotrophin-releasing hormone test is the most reliable noninvasive method to differentiate pituitary from ectopic ACTH secretion in Cushing's syndrome.

objective It has been reported previously that the paired interpretation of the corticotrophin‐releasing hormone (CRH) test and the 8‐mg dexamethasone suppression test (HDDST) could have higher diagnostic power than any single test in the differential diagnosis of ACTH‐dependent Cushings syndrome. This finding has not been confirmed thereafter in large series. The aim of the present study has been to assess the operating characteristics of either the CRH test or the overnight HDDST and also to evaluate the potential utility of combining the interpretation of both tests in the differential diagnosis of ACTH‐dependent Cushings syndrome.

Prospective evaluation of mitotane toxicity in adrenocortical cancer patients treated adjuvantly

Toxicity of adjuvant mitotane treatment is poorly known; thus, our aim was to assess prospectively the unwanted effects of adjuvant mitotane treatment and correlate the findings with mitotane concentrations. Seventeen consecutive patients who were treated with mitotane after radical resection of adrenocortical cancer (ACC) from 1999 to 2005 underwent physical examination, routine laboratory evaluation, monitoring of mitotane concentrations, and a hormonal work-up at baseline and every 3 months till ACC relapse or study end (December 2007). Mitotane toxicity was graded using NCI CTCAE criteria. All biochemical measurements were performed at our center and plasma mitotane was measured by an in-house HPLC assay. All the patients reached mitotane concentrations >14 mg/l and none of them discontinued definitively mitotane for toxicity; 14 patients maintained consistently elevated mitotane concentrations despite tapering of the drug. Side effects occurred in all patients but were manageable with palliative treatment and adjustment of hormone replacement therapy. Mitotane affected adrenal steroidogenesis with a more remarkable inhibition of cortisol and DHEAS than aldosterone. Mitotane induced either perturbation of thyroid function mimicking central hypothyroidism or, in male patients, inhibition of testosterone secretion. The discrepancy between salivary and serum cortisol, as well as between total and free testosterone, is due to the mitotane-induced increase in hormone-binding proteins which complicates interpretation of hormone measurements. A low-dose monitored regimen of mitotane is tolerable and able to maintain elevated drug concentrations in the long term. Mitotane exerts a complex effect on the endocrine system that may require multiple hormone replacement therapy.

Differential responses of serum and salivary interleukin-6 to acute strenuous exercise

Physical exercise is associated with elevation of serum levels of interleukin-6 (IL-6) because of its production in the muscles. The use of IL-6 measurements in saliva has been proposed in the field of immunopathology, mainly involving salivary gland disease. We evaluated the responses of serum and salivary IL-6 in two different groups of athletes submitted to different types of controlled strenuous exercise (spinning activity and maximal isokinetic test). Serum and salivary samples for IL-6 measurements, and serum samples for lactate and myoglobin determination before and after exercise, were obtained. Salivary IL-6 was measured by ELISA after dilution experiments and compared with results obtained by immunoradiometric assay. Spinning activity elicited significant increases in all the variables, and no correlation was found among the respective variations. A significant response to the isokinetic exercise was observed for serum IL-6, lactate and myoglobin only; no correlation was found between serum and salivary IL-6. Our study demonstrated that serum and salivary IL-6 responses to exercise are dissociated, possibly in relation to the lack of relationships between the systemic/muscular and the salivary routes of IL-6 production. Analytical issues that concern IL-6 measurement in saliva deserve attention, notably regarding the collection method used to absorb saliva. Concomitant monitoring of serum markers of inflammation, muscle metabolism and damage can provide information about muscle function properties and adaptations to physical effort in different types of athletes.

Sport-related hyperhomocysteinaemia: a putative marker of muscular demand to be noted for cardiovascular risk

Objective: Regular physical activity is associated with a reduction of cardiovascular morbidity and mortality; however, evidence of unfortunate cardiovascular events accompanying elite sport involvement continues to accumulate. To date, no information is available on possible peculiarities of the cardiovascular risk profile in athletes. Design: The aim of this study was to evaluate plasma homocysteine levels in a group of athletes and to search for relationship with vitamin status and other metabolic variables in order to confirm the existence of a “sport-related hyperhomocysteinaemia” and to explain its clinical significance. The study population was composed of 82 athletes (59 male and 23 female) practising different sports and 70 healthy age-matched subjects (40 male and 30 female) as a control group. Besides the general clinical and analytical determinations, the assessed variables included homocysteine, folate, vitamin B12, total and high-density lipoprotein (HDL) cholesterol, lactate dehydrogenase (LDH), creatine kinase (CPK) and interleukin-6 (IL-6). Results: The prevalence of hyperhomocysteinaemia (>15 μmol/l) in athletes and controls was 47% and 15%, respectively. No correlation was found between homocysteine and any of the other investigated variables, in particular plasma folate, blood pressure, LDH, CPK, total and HDL cholesterol and IL-6. Conclusion: The results of this study confirm the existence of a sport-related hyperhomocysteinaemia which appears linked neither to the same variables found in the general population, nor to specific training-related variables. We suggest that it would represent an adaptation to training but the possibility of a secondary vascular damage cannot be excluded.

The combined low-dose dexamethasone suppression corticotropin releasing-hormone test as a tool to rule out Cushing's syndrome

OBJECTIVE It remains to be evaluated whether the combined low-dose dexamethasone suppression corticotropin-releasing hormone test (LDDST-CRH test) may add to the diagnostic approach of patients suspected to have Cushings syndrome (CS). The aim of the present study was to evaluate whether the LDDST-CRH test may have a place in the diagnostic strategy of CS. DESIGN Prospective evaluation of a consecutive series of patients with suspected CS from 2004 to 2006. METHODS All the subjects underwent the same screening protocol including 1 mg dexamethasone suppression test, 24-h urinary free cortisol (UFC), and midnight serum cortisol, followed by the LDDST-CRH test whose results were not used to establish a definitive diagnosis. Plasma dexamethasone concentration was measured 2 h after the last dose of dexamethasone. Patients qualified for CS when at least two screening tests were positive. RESULTS Sixteen patients had CS while in the remaining 15 subjects CS was excluded. Even if not statistically significant, the sensitivity and the negative predictive value of the cortisol 15 min after CRH were better than the other tests; on the other hand, the test specificity was lower. All of the patients classified as indeterminate were correctly diagnosed by the LDDST-CRH test. Nevertheless, the repeated assessment of the screening tests and the active follow-up gave the same correct results. In all of the patients misclassified by the LDDST-CRH test, the plasma dexamethasone concentrations were in the normal range. CONCLUSIONS Based on our findings, we suggest that the LDDST-CRH test may still find a place as a rule-out procedure in patients who present with indeterminate results after screening and may be unavailable to repeat testing during follow-up.

Cortisol secretion, bone health, and bone loss: a cross-sectional and prospective study in normal nonosteoporotic women in the early postmenopausal period

OBJECTIVE The aim of the study was to evaluate the relationship between cortisol secretion, bone health, and bone loss in a cohort of normal women in the early postmenopausal period. METHODS We measured lumbar and hip bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) and heel ultrasound parameters in 82 healthy, nonosteoporotic (lumbar T-score ≥-2.0) women (median age 52.5 years, range 42-61). These women were examined in two sessions, 1 year apart, in the early postmenopausal period (onset of menopause between 6 and 60 months). Parameters of the hypothalamic-pituitary-adrenal (HPA) axis function were morning serum cortisol, morning and midnight salivary cortisol, 24-h urinary free cortisol (UFC), serum cortisol after 0.5 and 1 mg overnight dexamethasone, and DHEA-S. RESULTS In multiple regression analyses, the following significant inverse correlations were found: i) lumbar BMD and either 24-h UFC (P<0.005) or morning serum cortisol (P<0.05), ii) total femur and femoral neck BMD with morning serum cortisol (P=0.05 and P<0.05), and iii) heel ultrasound stiffness index and midnight salivary cortisol (P<0.005). The annual rate of change in lumbar and femoral BMD did not correlate with any of the above-mentioned hormonal variables. No difference was found in the parameters of HPA axis function in slow (loss of BMD <1%) vs fast (loss of BMD ≥3%) bone losers. CONCLUSIONS HPA axis may contribute to postmenopausal bone health, but differences in cortisol secretion do not influence the differential rate of bone loss between slow and fast bone losers in the early postmenopausal period, at least in healthy women.

Surgical remission of Cushing's syndrome reduces cardiovascular risk

OBJECTIVE Recent studies have questioned the reversibility of complications of Cushings syndrome (CS) after successful surgical treatment. The aim of this study was to assess the outcome of patients with CS who achieved disease remission compared with those patients with persistent hypercortisolism and matched controls. DESIGN A retrospective study of 75 patients with CS followed at an academic center. METHODS Cardiovascular risk profile was evaluated in 51 patients with CS in remission (group 1) and 24 patients with persistent disease (group 2) and compared with 60 controls. Mortality of patients with CS was compared with the background population. RESULTS In group 1, the frequency of cardiovascular risk factors dropped after disease remission even if it remained higher at the last follow-up than in the control group. In group 2, the frequency of cardiovascular risk factors remained unchanged during follow-up. The rate of cardiovascular and thromboembolic events was higher in group 2 than in group 1, as was the mortality rate (two deaths in group 1 and nine in group 2; ratio of two SMRs, 0.11; 95% CI, 0.011-0.512). Survival was significantly longer in group 1 than in group 2 (87 months, 80-98 vs 48 months, 38-62; P<0.0001). CONCLUSIONS Successful surgical treatment of hypercortisolism significantly improves cardiovascular risk and may reduce the mortality rate. Patients with persistent disease have increased morbidity and mortality when compared with patients in remission.