ACTA ENDOCRINOLOGICA (BUC)

Background: Simultaneously determined plasma chromogranin A (CgA) and free metanephrines can substantially enrich laboratory diagnosis of pheochromocytoma (PHEO). CgA-like\r\nimmunoreactivity was discovered in saliva. Salivary CgA (CgA-LIS) could precise PHEO diagnosis in a non-aggressive\r\nmanner for the patient using saliva instead of plasma samples.\r\nSubjects and methods: A group of 10 PHEO patients: 7 women (22 to 72 years ) and 3 men (42 to 59 years) and a control\r\ngroup of 10 subjects were included in this retrospective study. Plasma free metanephrines and CgA were assayed by\r\nElisa kits. Salivary CgA was assayed by an EIA kit. Both analytical and diagnosis performance of the CgA-LIS vs. CgA were compared using Passing& Bablok regression and Receiver Operating Curves (ROC analysis).\r\nResults: In tumor group, mean values for all 4 assayed parameters were significantly increased in comparison with\r\nthe same parameters in normal group as expected: free plasma normetanephrines (NMNp) was: 2773 ? 704.57pg/mL versus 48.51 ? 9.87 pg/mL in controls; free plasma metanephrines (MNp) was: 864.4 ? 330.75 pg/mL versus 19.18 ? 3.69 pg/mL in normals; CgA was: 695.10?235.22 ng/mL versus 74.4?5.37 ng/mL in controls; CgALIS was: 17.62?6.79 pmol/L versus 0.94 ?\r\n0.20 pmol/L in normals. Passing & Bablok regression equation for CgA-LIS versus CgA was: Y=0.0181 + 0.0146X. Cusum test\r\nfor linearity revealed no significant deviation from linearity (P>0.10). A significant correlation between NMNp and CgA-LIS was established in all 20 subjects: r=0.82, P<0.0001. Pairwise comparison of ROC curves for both markers showed no significant difference between areas. Salivary CgA could be successfully used instead of plasma CgA in biochemical diagnosis of pheochromocytoma.\r\nConclusions: We can conclude that salivary CgA could be used as a nonstressfull marker for diagnosis purpose in pheochromocytoma.

Introduction: The impaired transport of leptin into the brain through a decreased permeability of the blood-brain barrier (BBB) for leptin in obesity represents one of the important mechanisms involved in leptin resistance which is characteristic in human obesity. Some pituitary tumors can increase the blood-cerebrospinal fluid barrier (BCB) permeability for peptides. BCB is a part of BBB.\r\nObjectives: The aim of our study was to search if the by-pass of BCB for pituitary hormones produced by adenomas does influence the transport of leptin into the central nervous system in obese patients.\r\nMaterials and methods: We investigated 20 males with pituitary adenomas: group A (11 patients) had cerebrospinal fluid (CSF) to serum ratio more than one for prolactin (PRL) and in some patients for growth hormone (GH) and follicle stimulating hormone (FSH), suggesting an increased permeability of BCB and a control group C (9 patients), which had CSF/serum ratio less than one for GH, PRL or FSH, suggesting an intact BCB. Both A and C groups contain subgroups of patients with obesity (body mass index, BMI>30 kg/m2) and normal body weight (BMI<25 kg/m2). In these patients we measured the CSF to serum leptin ratio in order to clinically evaluate the leptin transport into the brain. Rapid fluoroimmunoassay method with europium was used. Leptin was assayed by ELISA method.\r\nResults: The patients of group A with pituitary adenomas show a higher level of pituitary peptides, PRL and in some cases GH, FSH in CSF as compared to serum (ratio CSF/serum over 1), both in obese and non-obese. By contrast, in the same patients, there is\r\na low level of CSF leptin as compared to serum leptin (ratio CSF/serum less than 1). In the subgroup of obese patients from group A we found even less ratio of CSF to serum leptin, than in non-obese. There is a well known higher leptin concentration in the plasma of obese patients with pituitary adenomas as compared to non-obese ones (26.4?3.8ng/ml vs 12.4?3.4ng/ml, p<0.05). In the control group C, both pituitary peptides (PRL, or GH, FSH) and leptin showed a ratio CSF/serum less than 1, in all patients.\r\nConclusions: These data show a decrease in hemato-encephalic barrier permeability for leptin in obese patients through a specific mechanism, not influenced by other peptides passing through injuries of BBB produced by pituitary adenomas. It is tempting to suggest that there is a specific by-pass of BCB for pituitary peptides, in some pituitary adenomas.

Leptin seems to play a significant role in the regulation of pituitary GH secretion. In GH deficient children serum leptin level is higher than in GH sufficient ones. Administration of rhGH resulted in a significant decrease in serum leptin in GH deficient but also in children displaying idiopathic growth delay, small for gestational age at birth, Prader-Willi syndrome and other obese. LBA is in fact the soluble form of leptin receptor. It was previously shown that GH deficient children are mostly hyperleptinemic and that GH induces a reduction in leptin level within 3 weeks of therapy. Such a reduction could serve as a valuable marker of the long term growth response. Twenty short children whose GH status was previously assessed through GH provocative tests and auxological evaluation were explored as concerns IGF I, leptin and LBA. According to these criteria they were classified as GH-deficient and GH-sufficient. Blood samples for the assay of serum leptin and LBA and IGF I were drawn at 8 a.m. A daily dose of 0.35 mg of rhGH was given subcutaneously at 8 pm in 12 of them and the same sampling was done 12 hours after the last injection. A therapy with GH with the same preparation and in comparable weekly dosage was started in all children and the height gain was evaluated after six months. Total serum leptin was assayed by a commercially available sandwich ELISA kit. LBA was assayed by a sandwich ELISA kit using a human IgG-Fc fragment of leptin receptor. IGF I determination was performed by the OCTEIA kit in a two-site immunoenzymometric assay (IEMA). The means and SEM before and after 10 days of GH administration in the whole group were of 3.4 ? 0.71 ng/ml and 1.7 ? 0.16 (p< 0.02) for leptin 0.27.1 ? 0.92 U/ml and 23.6 ?1.66 (ns) for LBA, 48.9 ? 10.65 ng/ml and 84.3 ? 17.61 for IGF I (p> 0.05, ns). Comparison between GH deficient (def) and GH sufficient (suf) subgroups resulted in significant differences as regards initial values for IGF I (20.2 ? 4.21 in def vs 77.6 ? 16.7 in suf, p< 0.02) but not in leptin, LBA, height and weight z scores. After ten days of therapy no significant differences were noted in subgroups for leptin, LBA and IGF I (absolute values), but a striking difference was noted in percentual rise of IGF I in def children. There was a significant positive correlation between leptin basal level and the growth rate in the subsequent 6 months of GH therapy. No similar correlation was noted for IGF I and LBA. It was concluded that hyperleptinemic GH deficient children seem to be particularly sensitive to the growth promoting effect of rhGH at least in the first six months of therapy.

Context. Despite CT being generally used in thymic pathology, in the case of regions with the same tissue density, only functional radioisotopic imaging can hint towards malignity. Objectives. To assess the usefulness of 99mTc MIBI scintigraphy for diagnosis and treatment planning in thymoma, in relation with the radiotracer uptake mechanism. Patients and methods. 99mTc MIBI thymic scans for 19 patients diagnosed with thymic disorders were assessed using tumor uptake ratio (UR). Specimens of thymectomies were examined and cytological assessments were correlated with the UR. Results. The UR of all surgical patients was higher than 1.2, with a 1.5 cutoff between lymphoid hyperplasia and thymoma. The UR values were correlated with the histopathologic diagnosis (Pearson correlation 0.91, significant at p<0.01). The highest UR was 3.24, found in the case of an AB thymoma where the rate lymphocytes/ epithelial cells (L/E) was 1.6. In B1 thymoma UR was 1.14 and L/E was 2.46. Conclusion. Phenotype differences between thymoma types correlate with 99mTc MIBI cellular uptake: lower rate L/E corresponds to higher UR, higher malignity potential and invasiveness. A thymic 99mTc MIBI UR higher than 1.5, corresponding to a CT tumoral image, is suggestive for a thymoma, requiring surgical treatment first.

Serotonergic 5HT2A receptors constitute the sole subtype identifiable in platelets, their sole location outside CNS. They may intervene in intra-CNS pathways involved in GHRH and GH release, mainly during sleep. To gain information about such a subtype receptor in GH deficiency and, indirectly, on its role in GH release, studies on the platelets membrane binding sites of labelled LSD were undertaken in dwarf, GH-deficient children, assuming that the platelets sites number is parallel to their number in the brain. Five dwarf (Dw) children (3 boys) aged 7-13, having no signs of puberty, with a peak GH level under 5 ng/ml during ITT, no tumor in the hypothalamic and pituitary area and no previous rhGH therapy were compared with ten normally statured, non-obese children serving as controls (C). Fifty mL of platelet membrane preparation of pooled samples were incubated at 25?C with radioiodinated lysergic acid diethylamide ([125I] LSD) in concentrations of 0.35-3.5 nM/L. The reaction kinetics was followed up within 60 min weekly for 4 weeks. Bmax and Kd were calculated as means of 4 repetitions. Competitive inhibition curves were also drawn by using ketanserin (KET), mianserin (MIA) and cyproheptadin (CYP) in concentrations of 10-4 mM- 1nM/L and the inhibition constant (Ki) was calculated. The results showed that Bmax was (mean ? SEM) 33.0 ? 3.06 fmol/mg protein in C group versus 64.06 ? 13.82 fmol/mg protein in Dw group (F test in covar p<.05). Kd was 0.76? 0.166 nM in C and 2.0? 0.48 nM in Dw (t test p<0.01). The earliest time of 100% binding (Tmin) was 20 min in C and 5 min in Dw groups. Ki in C was 0.1 nM for KET, 18 nM for MIA and <0.1 nM/L for CYP. In Dw children Ki was 1.85 nM for KET, 18 nM for MIA and <0.1 nM for CYP. The results indicated that the number of 5HT2A receptors in platelets was significantly greater in GH-deficient children than in controls, as well as Kd. Tmin indicated an earlier steady state in Dw patients. Ki values pleaded to some extent in favour of the presence of excess 5HT2A receptors. In conclusion, excessive binding of labelled LSD and its inhibition by specific antagonists proves excess of 5HT2A receptors in platelets preparations collected from dwarf children.

Background. Advances in imaging techniques have led to increasing discovery of\r\nadrenal and pituitary &#8220;incidentalomas&#8221;, tumors with normal endocrine function and no\r\ncompression mass effects. We evaluated the age at diagnosis (AD) in patients with benign\r\nnon-functioning adrenal incidentalomas, as compared to pituitary non-functioning tumors,\r\nin a series of patients from a national center of endocrinology. Methods. From 2,123\r\nconsecutive patients with adrenal and pituitary tumors hospitalized between 1977 - 2009,\r\n2,069 patients were analysed. The study groups included: group A - 137 patients with\r\nadrenal incidentalomas (AI), group B - 534 patients with pituitary incidentalomas (PI).\r\nControl groups included 1,398 patients: group C1 147 patients with adrenal carcinomas or\r\nbenign hormone-secreting adrenal tumors, and group C2, 1,251 patients with pituitary\r\nsecreting adenomas or large non-functioning pituitary macroadenomas (NFA). Imaging was\r\ndone by computed tomography and/or magnetic resonance after 1981 and by skull X-ray or\r\npneumoencephalography before 1981. Results. Mean age AD is more advanced in patients\r\nwith AI (53 ? 11.9 years, range 21 - 78 yr) than in patients with PI (36.8 ? 13.1 years, range\r\n10 - 81 yr), p < 0.01. AD was higher in AI than in patients with secreting adrenal tumors,\r\nbut similar in patients with adrenal malignancy. There is an age-related increase in the\r\nproportion of AI among patients with adrenal tumors, and of NFA, but not of PI, among\r\npatients with pituitary tumors. In patients aged over 65 years, 74% of patients with adrenal\r\ntumors have AI, while only 18% of patients with pituitary tumors have PI and 42% have\r\nNFA. AD in NFA (49.3 ? 13.1 yr, range 12 - 79 yr) was more advanced than in PI (p < 0.01).\r\nAD does not correlate with tumor size. Tumor growth occurred in 24% of AI (follow-up 3.0\r\n? 2.8 yr) and only in 0.7% of PI, p<0.01 (follow-up 3.1 ? 2.5 yr).\r\nConclusions. Adrenal non-functioning benign tumors show a clear association with ageing,\r\nin contrast with pituitary incidentalomas. It seems unlikely that most pituitary incidentalomas in\r\nyoung patients become large NFA, whose development seems to be also age-related. It is tempting\r\nto suggest that pituitary tumorigenesis starts earlier than adrenal tumorigenesis.

A 62 years old woman was diagnosed with multinodular toxic goiter and primary hyperparathyroidism/ left parathyroid adenoma by hormonal assessment, ultrasound and nuclear thyroid/parathyroid scans. Cervical ultrasound illustrated a multinodular aspect of the thyroid with solid nodules and cystic-component nodules; the larger one represented a multinodular complex with necrosis areas in the left thyroid lobe, ACR TI-RADS score 4 (moderately suspicious). Functional nuclear imaging was performed for accurate differential diagnosis between thyroid vs. parathyroid localization, between cold vs. hot nodules, and eventually, for guiding the choice of a subsequent Fine- Needle Aspiration Biopsy (FNAB). Scans described an early intense 99mTc-sestaMIBI uptake with no 99mTc-pertechnetate uptake in the left thyroid lobe larger nodule. Due to the suspicion of malignancy for this nodule, we performed an additional scan (1 hour before the classical 2 hours parathyroid delayed scan). The intense uptake persists in both delayed scans suggesting no malignant phenotype and which was confirmed after surgery by benign histology. In conclusion, using a 99mTc-sestaMIBI personalized protocol, related to the radiotracer cellular uptake mechanisms: 1 hour scan (supplementary image, corresponding to the maximum uptake pattern of 99mTc-sestaMIBI for cancer cells) and 2 hours scan (for parathyroid washout evaluation) may avoid unnecessary extensive thyroid surgery.

Background: Salivary monitoring of hormone levels has many advantages over the more conventional serum/plasma analysis. Salivary free metanephrines (MN) and normetanephrines (NMN) could precise biochemical diagnosis of pheochromocytoma (PHEO) as an alternative to plasma metabolites.\r\nSubjects and methods: The prospective case-control study included a group of 30 patients confirmed with PHEO an age-matched control group of 70 normotensive subjects. The PHEO diagnosis was suspected on clinical ground and confirmed by imaging studies and classical neuroendocrine markers. Free plasma and salivary NMN and MN were assayed using enzyme immunoassay for both metabolites.\r\nResults: In tumor cases all metabolites were increased. As expected, values for all 4 parameters (mean?SEM) differed significantly in tumor group vs. normal group: free plasma\r\nnormetanephrines (NMNp): 1514.16 ? 282.97 pg/mL vs 47.82?2.52 pg/mL; free salivary normetanephrines (NMNs):\r\n663.63?168.47 pg/mL vs 44.98? 2.47 pg/mL; free plasma metanephrines (MNp): 445.20 ? 99.92 pg/mL vs 18.87?1.03\r\npg/mL; free salivary metanephrines (MNs):206.60?91.48 pg/mL vs 14.47?0.72 pg/mL with significant correlations in all\r\n100 subjects. Passing & Bablok regression showed no significant deviation from linearity in Elisa assay of NMNs vs NMNp; a significant deviation from linearity existed\r\nin Elisa assay of MNs vs MNp. Cut-off values, sensitivity and specificity for all 4 parameters were calculated by ROC\r\nanalysis. Plasma and salivary normetanephrines proved similar sensitivity (100%) and specificity (100%). Pairwise\r\ncomparison of ROC curves areas showed no significant differences between NMNp vs NMNs and MNp vs MNs. Ten cases were investigated post-surgery. All 4 parameters\r\nshowed no significant differences vs. control group.\r\nConclusions: Salivary free normetanephrines could be used as a nonstressful marker for diagnosis purpose in pheochromocytoma proving similar sensitivity and specificity as plasma free normetanephrines.

-