Chromogranin A (CgA)--the influence of various factors in vivo and in vitro, and existing disorders on it's concentration in blood.

Chromogranin A (CgA) is regarded as a major, nonspecific neuroendocrine tumour (NET) marker. The results of CgA blood concentration, however, may actually be influenced by various factors or coexisting pathological conditions. Among the factors causing a substantial increase of the blood CgA concentration are: treatment with proton-pump inhibitors or H2-receptor blockers, chronic atrophic gastritis (type A), impaired renal function, prostate cancer and BPH, and rheumatoid arthritis with high level of RF IgM. In addition, the sort of investigated biological material (whether it is serum or plasma) is of importance. There are also many conditions which may have a moderate or little influence on the concentration of CgA, among them are: inflammatory bowel disease (ulcerative colitis and Crohn's disease), deteriorating liver function, untreated essential hypertension, heart failure, hypercortisolism, pregnancy, and, in some subjects, ingestion of a meal. Proper assessment of the CgA results requires detailed knowledge about various factors, drugs, and pathological conditions influencing its concentration in blood.

The differences in chromogranin A (CgA) concentrations measured in serum and in plasma by IRMA and ELISA methods.

INTRODUCTION: Chromogranin A (CgA) is regarded as a major, nonspecific marker of neuroendocrine tumors (NET). Its estimation appears helpful for diagnostic purposes and is particularly useful for monitoring the treatment of NET. It must be kept in mind, however, that various factors, drugs, or coexisting diseases may influence the outcome of CgA measurement in blood. One such analytical factor is the sort of studied biological material, whether it is plasma or serum. The aim of our study was to compare directly the results of CgA concentrations measured in serum and in plasma by IRMA and ELISA. MATERIAL AND METHODS: We analysed 122 samples of EDTA-plasma and 122 samples of serum by IRMA method, 20 samples of EDTAplasma and 20 samples of serum by IRMA and ELISA, 25 heparinised-plasma samples and 25 samples of EDTA-plasma by IRMA and ELISA methods, and 8 EDTA-plasma, heparinised-plasma, and serum samples by IRMA and ELISA. The material for comparative study was obtained during the same blood collection from the same subjects (volunteers and patients with NET). CgA was measured with the use of kits manufactured by CIS bio International (France). RESULTS: CgA concentrations were markedly higher in plasma than in serum. Using the IRMA method, the difference in the CgA range between 10-100 ng/mL approached 20-70% (median 61 v. 42), in the range 101-300 ng/mL--12-60% (median 147 v. 101), and in the CgA range 301-1076 ng/mL--14-40% (median 486 v. 356). The differences between results in serum and plasma using ELISA were similar but slightly smaller. There was no significant difference between CgA levels in EDTA and heparinised-plasma samples, and the results of measurements performed by IRMA and ELISA in most cases were similar. CONCLUSIONS: Referring each individual CgA result to the proposed reference range (or cut-off value) we must take into account whether the measurement is performed in plasma or in serum.

The role of combined low-dose dexamethasone suppression test and desmopressin stimulation test in the diagnosis of persistent Cushing's disease. Case report.

Cushing's disease is related to a significant increase in mortality due to chronic hypercortisolaemia complications. It is known that 50% of non-treated subjects die within 5 years. Transsphenoidal selective adenomectomy is the treatment of choice. The incidence of relapses, even following a successful surgical procedure, is high and reaches 20-25% during the 5-year follow-up period. The authors discuss the case of a patient, currently aged 60, after repeat pituitary surgery, with progressive cardiovascular complications, in whom persistent Cushing's disease was diagnosed. The diagnosis was determined despite normal plasma ACTH, serum cortisol levels, and 17-OHCS concentrations in daily urine. There was also a lack of obvious pituitary adenoma features in the magnetic resonance imaging (MRI). Persistent Cushing's disease was diagnosed based on the combined dexamethasone desmopressin test. The presented case points to the role of provocative testing, including the desmopressin test following 1 mg of dexamethasone, for diagnostically difficult cases of Cushing's disease.

Bilateral, incidentally found adrenal tumours - results of observation of 1790 patients registered at a single endocrinological centre.

INTRODUCTION: During the last 22 years we registered 1790 patients with incidentally found adrenal tumours (AI, adrenal incidentalomas). In 351 of them, bilateral tumours were detected. The aim of our study was to analyze the character of bilateral tumours and summarize the methods of their management. MATERIAL AND METHODS: In the whole group of 1790 patients, there were 1311 women and 479 men, aged 11-87 years. The group of patients with bilateral adrenal tumours included 258 women and 93 men, 25-83 years old. Hormonal investigations and imaging examinations were performed to search for subclinical adrenal hyperfunction and to define the malignant potential of the tumours. RESULTS: Sixty-nine patients were treated by surgery for oncological or endocrinological purposes (mainly pre-Cushing's syndrome). Histological findings included malignant tumours: metastases - 9, adrenal cancer - 7, and lymphomas - 5; and non-malignant tumours: adenomas - 24, nodular hyperplasia - 14, myelolipomas - 4, and pheochromocytomas - 4. Subclinical Cushing's syndrome was relatively more frequent in nodular hyperplasia (40%) than in adenomas (30%). CONCLUSIONS: Indications for surgery were recommended in 20% of patients with bilateral AI, most frequently for adenomas, nodular hyperplasia, and oncological pathologies, with a good prognosis in the non-malignant group. (Pol J Endocrinol 2010; 61 (1): 69-73).

[Chromogranin A (CgA) - characteristic of the currently available laboratory methods and conditions which can influence the results]. / Chromogranina A (CgA)- charakterystyka dostepnych metod badawczych i unwarunkowan mogacych miec wplyw na uzyskane wyniki.

Chromogranin A is a main, nonspecific neuroendocrine tumor marker (NET). It's estimation was applied for diagnostic purposes and for monitoring the treatment of NET. Currently few commercial assays are available allowing measurement of CgA concentration in serum or plasma. These methods have various sensitivity and specificity and differ in many analitycal parameters. Numerous factors and pathologies may influence the outcome of the CgA measurement. Therefore, a review article on this matter may be useful for clinical and laboratory practice.

[The main reasons behind variability in detection of prolactin and causes of true or apparent discordance with clinical state]. / Przyczyny rozbieznosci wyników oznaczen prolaktyny i powody prawdziwej albo pozornej niezgodnosci ze stanem klinicznym.

Both the "hook" effect and macroprolactinaemia, are the main reasons behind the discrepancy of serum prolactin level results in various laboratories. They can cause the diagnostic dilemmas or even completely faulty diagnosis resulting with undertaking of unnecessary investigations and/or an inappropriate method of treatment. Therefore, a review article on this matters may be of some help for clinical practice.

ACTH responses to somatostatin, valproic acid and dexamethasone in Nelson's syndrome.

OBJECTIVE: Pituitary tumours occurring in patients bilaterally adrenalectomized because of Cushing's disease (Nelson's syndrome) are frequently invasive and a complete their resection is not possible in most of them. Administration of the drugs decreasing ACTH secretion could be helpful in such unresectable tumours. We tried to evaluate the influence of somatostatin and valproic acid, compared to dexamethasone, in short-term studies, on plasma ACTH levels in Nelson's syndrome (NS). MATERIAL AND METHODS: Basal ACTH levels were determined within 18 h after last dose of hydrocortisone and next, 1 and 2 hours following oral administration of 20 mg of hydrocortisone. Somatostatin was injected s.c. in two patients with NS while sodium valproate and dexamethasone were administered orally for three days in three patients with NS (two with an invasive pituitary tumour and one with a localized, intrasellar adenoma). The blood for ACTH and cortisol determination was drawn before the tests (two hours after 20 mg of hydrocortisone ingestion) as well as 1 and 2 hours following somatostatin injection and after 3 days of valproic acid or dexamethasone administration. RESULTS: High plasma ACTH levels were found before the tests. Somatostatin lowered ACTH levels in both patients, more effectively in the patient with non-invasive pituitary adenoma. Valproic acid decreased moderately ACTH concentration in two patients, while following dexamethasone administration a fall in ACTH levels was observed in all three patients, the most evident in the patient with a non-invasive Nelson's adenoma. CONCLUSION: Somatostatin seemed to be more effective in its inhibitory action on ACTH secretion than valproic acid, thus its administration in invasive cases of NS could be tried as a supplementary method to neurosurgery. The response to dexamethasone administration indicates that a feed-back regulation, although impaired, exists in these cases.

[Macroprolactin in subjects with hyperprolactinaemia: clinical observations and relations between free PRL and PRL complexed with IgG]. / Makroprolaktyna u osób z hiperprolaktynemia: obserwacje kliniczne i relacje pomiedzy frakcja prolaktyny wolnej i frakcja prolaktyny zwiazanej z IgG.

UNLABELLED: In some patients with hyperprolactinaemia a large portion of circulating prolactin is bound to authologous gammaglobulin and therefore it is called macroprolactin or Big-Big-Prolactin (BB-PRL). THE AIM: of the study was to select patients with predominance of macroprolactin and to learn more about the natural course of this disorder, in particular about the possible dependence of the presence of clinical features from the amount of circulating "free" PRL level, and also to search whether the quantitative proportions of both forms of PRL are stable or they change parallel to changes of the total serum PRL level. MATERIAL AND METHODS: We identified 58 patients with hyperprolactinaemia, in whom BB-PRL consisted>or=60% of the total PRL concentration. The predominance of macroprolactin was settled using the well accepted method of polyethylene glycol (PEG) precipitation of large m.w. serum proteins, followed by contemporary immunoradiometric measurement of the total and free PRL levels, and calculation of BB-PRL. Repeating such measurements during the long term observation lasting 6-66 months (mean 33 months), which was possible in 18 our patients (13--with idiopathic hyperprolactinaemia and 5--with pituitary adenoma), we could analyze the relations between both forms of PRL during the specific treatment, after it's cessation and, in few cases--during pregnancy. Apart of that, in 18 patients selected from 53 with idiopathic hyperprolactinaemia, we analyzed the shortterm alterations in the ratio between free and complexed PRL during the metoclopramide PRL stimulation test. RESULTS AND CONCLUSIONS: 1. In hyperprolactinaemic patients with predominance of BB-PRL, there was no direct correlation between the presence of clinical features and the concentration of residual "free" PRL. 2. During the long-term observation, in spite of moderate changes in the total PRL concentration induced by the treatment or it's cessation (excluding pregnancy), the ratio of "free" PRL and BB-PRL remained stable. 3. During the short time of metoclopramide stimulation test, there was a marked rise mainly of the total and "free" PRL concentrations, and, in some tested subjects, the predominance of BB-PRL was lost temporally for 1 to 2 hours.

Comparison of chromogranin A (CgA) levels in serum and plasma (EDTA2K) and the respective reference ranges in healthy males.

INTRODUCTION: Chromogranin A (CgA) is a major, nonspecific marker of neuroendocrine tumours (NET). There are a few routinely used assays for the measurement of CgA concentration in serum or plasma. These assays differ in analytical techniques (radioimmunoassay, ELISA, CLIA, TRACE), have different calibrators, and use different antibodies which recognise different epitopes of CgA molecule. Our study was designed to confirm the noted earlier differences in CgA levels measured in serum and plasma, and to establish respective reference ranges in a group of healthy males. MATERIAL AND METHODS: In 145 male blood donors (age 19-61 years, mean = 35.7), blood was collected into two tubes: one with EDTA2K (plasma) and one with clot activator (serum). Chromogranin A was measured by immunoradiometric kit (CIS bio, France). RESULTS: In blood donors, the median (and the range) of CgA concentration were as follows for serum samples - 42.0 ng/mL (16-108 ng/mL) and for plasma (EDTA2K) samples - 58.0 ng/mL (23-153 ng/mL). The differences between serum and plasma ranged 15-75% (median 26%). Plasma CgA levels were significantly higher in relation to serum CgA levels (p < 0.0001). Correlation of CgA in serum and plasma was r = 0.8493; p < 0.01. The reference ranges for CgA measured in serum and plasma in males, expressed as 2.5 to 97.5 percentiles, were: 21.0-108.0 ng/mL and 31.0-153.0 ng/mL respectively. CONCLUSIONS: 1. Significant differences in the concentrations of CgA measured in plasma and in serum demand the application of separate reference ranges adjusted to the type of investigated material. 2. Each laboratory should recommend only one sort of sample material for CgA assay.

The effect of blood collection procedure on plasma renin activity (PRA) and concentrations of direct renin (DRC) and aldosterone.

INTRODUCTION: Performing measurements of plasma renin activity (PRA) or direct renin concentration (DRC) and aldosterone concentration, we should be well informed about requirements concerning blood sample processing. MATERIAL AND METHODS: Forty-seven patients had blood collected in the supine and upright positions. Blood was withdrawn into two EDTA2K tubes and one with clot activator. One EDTA2K tube was cooled at +4 °C and centrifuged at +4 °C whereas the other was prepared at room temperature. PRA and DRC were measured by radioimmunoassay (RIA) and radioimmunometry (IRMA), respectively, in both cooled and not cooled plasma samples, and aldosterone was measured by RIA in not cooled plasma and in serum. RESULTS: In all the groups, with low, medium, and high values of PRA and direct renin, the temperature of sample processing within 30 minutes had no marked influence on the final result (correlation coefficient for renin was 0.9994, and for PRA, 0.8297). The measured concentrations of aldosterone also showed high correlation (r = 0.9790) but were markedly higher in plasma. CONCLUSION: The measurements of DRC, and to a lesser extent PRA, were similar regardless of temperature condition during the 20-30 minutes necessary for blood sample processing. Aldosterone concentrations in plasma vs serum samples appeared to be markedly higher.

The ratios of aldosterone / plasma renin activity (ARR) versus aldosterone / direct renin concentration (ADRR).

Primary aldosteronism (PA) is estimated to occur in 5-12% of patients with hypertension. Assessment of aldosterone / plasma renin activity (PRA) ratio (ARR) has been used as a screening test in patients suspected of PA. Direct determination of renin (DRC) and calculation of aldosterone / direct renin concentration ratio (ADRR) could be similarly useful for screening patients suspected of PA. The study included 62 patients with indication for evaluation of the renin-angiotensin-aldosterone system and 35 healthy volunteers. In all participants we measured concentrations of serum aldosterone, plasma direct renin, and PRA after a night's rest and again after walking for two hours. The concentrations of aldosterone, direct renin, and PRA were measured by isotopic methods (radioimmunoassay (RIA) / immunoradiometric assay (IRMA)). Correlations of ARR with ADRR in the supine position were r = 0.9162, r(2) = 0.8165 (p < 0.01); and in the up-right position were r = 0.7765, r(2) = 0.9153 (p < 0.01). The cut-off values of ARR and ADRR ≥ 100 presented highest specificity (99%) for the diagnosis of PA; however, quite acceptable specificity and sensitivity (> 80% and 100%, respectively) appeared for the ratios ≥ 30. We suggest that for practical and economic reasons ARR can be replaced by ADRR.

Fetuin-A levels in lean and obese women with polycystic ovary syndrome.

INTRODUCTION: The aim of this study was to estimate serum fetuin-A levels in lean and obese women with polycystic ovary syndrome (PCOS) and to find possible relationships between fetuin-A, metabolic factors and androgens in these patients. MATERIAL AND METHODS: In 25 lean (18-38 years, BMI 17.5-25.0 kg/m2) and 15 obese women (20-41 years, BMI 28.1-53.2 kg/m2) with PCOS, anthropometric indices and body composition were measured. Fasting serum fetuin-A, adiponectin, leptin, glucose, lipids, hsCRP, insulin, androgens and SHGB levels were estimated. RESULTS: There was no significant difference in serum fetuin-A levels between lean and obese patients: 0.54 ± 0.13 g/L and 0.60 ± 0.14 g/L, respectively. We noted a correlation between BMI and leptin levels (r = 0.88; p < 0.0001) and a nearly significant negative correlation between BMI and adiponectin levels (r = -0.53; p = 0.11) in all subjects. In lean patients, we found a correlation between fetuin-A levels and ALT activity (r = 0.44; p < 0.05). In all participants, fetuin-A correlated directly with DHEA-S levels (r = 0.44; p < 0.03). CONCLUSIONS: Serum fetuin-A levels were similar in lean and obese women with PCOS. We found an association between fetuin-A levels and ALT activity in lean patients and between fetuin-A levels and DHEA-S in all women. The role of fetuin-A in the mechanisms of insulin resistance, and its potential impact on androgenic hormones production in women with PCOS, need to be tested in further studies.

Proinsulin, adiponectin and hsCRP in reproductive age women with polycystic ovary syndrome (PCOS)--the effect of metformin treatment.

INTRODUCTION: Women with polycystic ovary syndrome (PCOS) often suffer from obesity and insulin resistance. The role of proinsulin, which is known to be an indicator of fertility outcomes in PCOS women, and that of adiponectin, in the pathogenesis of PCOS is not well elucidated. Our objective was to determine proinsulin, adiponectin, hsCRP and other hormonal and metabolic parameters in PCOS women before and after metformin treatment. MATERIAL AND METHODS: Two PCOS groups of patients of reproductive age (90 lean and 88 obese or overweight) with two control groups, adjusted for body mass index (BMI), were compared at baseline. 32 PCOS women were studied at baseline, after three and six months of metformin (1,000 mg/day) treatment. Clinical, anthropometric, biochemical and hormonal parameters were assessed. RESULTS: Proinsulin and hsCRP levels were the highest in obese PCOS women and were statistically different than in lean PCOS women (proinsulin: 11.4 v. 6.9 pmol/L; hsCRP 2.46 v. 0.47 mg/L, p < 0.01) and than in obese controls. Levels of adiponectin were dependant on BMI. Plasma proinsulin and androstenedione levels decreased after metformin treatment only in obese PCOS women. CONCLUSIONS: PCOS, when accompanied by obesity, is associated with elevated proinsulin concentrations, which correlates with higher hsCRP and increased FAI. Proinsulin level decreases due to metformin treatment. Our results suggest that obese or overweight PCOS and lean PCOS are characterised by different hormonal and metabolic parameters and have a different response to metformin treatment.

Chromogranin A (CgA) in adrenal tumours.

INTRODUCTION: Adrenal tumours can produce specific hormones and cause characteristic symptoms. The majority of adrenal incidentalomas are clinically silent, but some may be malignant or pose other potential threats to life. Chromogranin A (CgA) is the main, nonspecific marker of neuroendocrine tumours (NET). In the adrenals, CgA is produced by chromaffin cells localised in the adrenal medulla. Therefore its measurement in blood might be used as a screening test for pheochromocytoma after the exclusion of other various causes of an increased CgA level. The aim of our study was to investigate plasma CgA concentration in various adrenal tumours. MATERIAL AND METHODS: EDTA2K plasma samples were obtained from 195 patients with adrenal tumours and from 50 blood donors. CgA was measured in plasma-EDTA2K by immunoradiometric (IRMA) method. RESULTS: In the majority of patients with adrenal tumours not derived from neuroendocrine cells (chromaffin cells), except those with significant hypercortisolaemia and some patients with adrenal carcinoma, the plasma CgA concentrations were below the cut-off value. In adrenal tumours derived from chromaffin cells (pheochromocytoma), CgA levels were markedly elevated. CONCLUSION: In differential diagnosis of adrenal tumours, non-increased CgA level might be useful initial screening evidence for the exclusion of pheochromocytoma.

Supplementation with hydrocortisone on the 3rd-5th day following dexamethasone premedicated chemotherapy eliminated severe dizziness and postural hypotension.

We present the case of a 60 year-old woman with a stage III fallopian tube cancer submitted to hysterectomy and bilateral salpingo-oophorectomy with partial omenectomy, followed by six courses of chemotherapy and revision surgery. After each course of chemotherapy (paclitaxel + carboplatin) preceded by premedication with dexamethasone, she suffered from side- -effects, of which the most unpleasant was severe dizziness appearing on the third, fourth and fifth day following the listed combination of drugs. It was revealed that dizziness with concomitant sweating and rapid pulse, noted in the standing position, was combined with marked postural hypotension. Considering the possibility of a temporary pituitary-adrenal axis suppression caused by premedication with a very large dose of dexamethasone, during those three days she was supplemented with small doses of hydrocortisone, which caused almost complete disappearance of the mentioned symptoms. Our conclusion is that postural hypotension causing severe dizziness initially linked with chemotherapeutic drugs can be eliminated or markedly reduced by three days supplementation with hydrocortisone applied after the expected wash out of the dexamethasone.

Quality of life in European patients with Addison's disease: validity of the disease-specific questionnaire AddiQoL.

CONTEXT: Patients with Addison's disease (AD) self-report impairment in specific dimensions on well-being questionnaires. An AD-specific quality-of-life questionnaire (AddiQoL) was developed to aid evaluation of patients. OBJECTIVE: We aimed to translate and determine construct validity, reliability, and concurrent validity of the AddiQoL questionnaire. METHODS: After translation, the final versions were tested in AD patients from Norway (n = 107), Sweden (n = 101), Italy (n = 165), Germany (n = 200), and Poland (n = 50). Construct validity was examined by exploratory factor analysis and Rasch analysis, aiming at unidimensionality and fit to the Rasch model. Reliability was determined by Cronbach's coefficient-α and Person separation index. Longitudinal reliability was tested by differential item functioning in stable patient subgroups. Concurrent validity was examined in Norwegian (n = 101) and Swedish (n = 107) patients. RESULTS: Exploratory factor analysis and Rasch analysis identified six items with poor psychometric properties. The 30 remaining items fitted the Rasch model and proved unidimensional, supported by appropriate item and person fit residuals and a nonsignificant χ(2) probability. Crohnbach's α-coefficient 0.93 and Person separation index 0.86 indicate high reliability. Longitudinal reliability was excellent. Correlation with Short Form-36 and Psychological General Well-Being Index scores was high. A shorter subscale comprising eight items also proved valid and reliable. Testing of AddiQoL-30 in this large patient cohort showed significantly worse scores with increasing age and in women compared with men but no difference between patients with isolated AD and those with concomitant diseases. CONCLUSION: The validation process resulted in a revised 30-item AddiQoL questionnaire and an eight-item AddiQoL short version with good psychometric properties and high reliability.