Prasanna Santhanam

Role of 18F-FDOPA PET/CT imaging in endocrinology

18F‐FDOPA (6‐[18F]‐L‐fluoro‐L‐3, 4‐dihydroxyphenylalanine)‐based PET/CT imaging can be a useful tool for the detection of different neuroendocrine tumours (NETs). 18F‐FDOPA is taken up into the cells via the neutral amino acid transporter (LAT1/4F2hc). This transporter is also coupled to the mammalian target of rapamycin (mTOR) signalling pathway. 18F‐FDOPA PET/CT may be performed for confirmation of diagnosis of pheochromocytoma/paraganglioma, staging at initial presentation, restaging and follow‐up of patients. In SDHx‐related syndromes, 18F‐FDG PET/CT should be performed in addition to 18F‐FDOPA PET/CT. 18F‐FDOPA PET/CT is also invaluable in the detection staging/restaging of carcinoid tumours and has greater sensitivity as compared to somatostatin receptor scintigraphy. 18F‐FDOPA PET/CT can also distinguish between focal vs diffuse CHI. It is not as useful in adult hyperinsulinism due to increased background uptake, but the problem may be overcome with the help of premedication with carbidopa. It has limited use in pancreatic NETs. 18F‐FDOPA PET/CT is a good modality for detection of persistent and residual medullary thyroid cancer (MTC), but 18F‐FDG PET/CT may be needed in aggressive tumours. In summary, F‐DOPA PET/CT has widespread utility in the diagnosis of different neuroendocrine tumours.

Role of Dietary Components in Modulating Hypertension

Hypertension is a major health issue, particularly in medically underserved populations that may suffer from poor health literacy, poverty, and limited access to healthcare resources. Management of the disease reduces the risk of adverse outcomes, such as cardiovascular or cerebrovascular events, vision impairment due to retinal damage, and renal failure. In addition to pharmacological therapy, lifestyle modifications such as diet and exercise are effective in managing hypertension. Current diet guidelines include the DASH diet, a low-fat and low-sodium diet that encourages high consumption of fruits and vegetables. While the diet is effective in controlling hypertension, adherence to the diet is poor and there are few applicable dietary alternatives, which is an issue that can arise from poor health literacy in at-risk populations. The purpose of this review is to outline the effect of specific dietary components, both positive and negative, when formulating a dietary approach to hypertension management that ultimately aims to improve patient adherence to the treatment, and achieve better control of hypertension.

PET imaging in ectopic Cushing syndrome: a systematic review

Abstract Cushing syndrome due to endogenous hypercortisolism may cause significant morbidity and mortality. The source of excess cortisol may be adrenal, pituitary, or ectopic. Ectopic Cushing syndrome is sometimes difficult to localize on conventional imaging like CT and MRI. After performing a multilevel thoracoabdominal imaging with CT, the evidence regarding the use of radiotracers for PET imaging is unclear due to significant molecular and etiological heterogeneity of potential causes of ectopic Cushing’s syndrome. In our systematic review of literature, it appears that GalLium-based (Ga68) somatostatin receptor analogs have better sensitivity in diagnosis of bronchial carcinoids causing Cushing syndrome and FDG PET appears superior for small-cell lung cancers and other aggressive tumors. Further large-scale studies are needed to identify the best PET tracer for this condition.

DIAgNOsTIC PREDICAmENT Of sECONDARy ADRENAl INsuffICIENCy

OBJECTIVE To propose an approach for the diagnosis of secondary adrenal insufficiency (AI) by presentation of 2 clinical cases and review of the literature. METHODS We describe 2 patients who were considered to have a normal hypothalamic-pituitary-adrenal axis on the basis of an appropriate response to the high-dose (250 microg) cosyntropin stimulation test (HST), with use of a cutoff value of 20 microg/dL. Our first patient had undergone resection of a 4-cm pituitary tumor a few months previously, and the second patient had hyponatremia with empty sella syndrome. Both patients, however, had strong clinical evidence suggestive of secondary AI. On testing by the insulin tolerance test (ITT) in the first patient and the overnight metyrapone test (OMT) in the second patient, secondary AI was diagnosed. We reviewed the literature to compare the utility of the different tests for the diagnosis of secondary AI. RESULTS An 8 AM serum cortisol value less than 5 microg/dL or above 13 microg/dL and a stimulated cortisol level less than 16 microg/dL on both the low-dose cosyntropin stimulation test (LST) and the HST as well as above 22 microg/dL on the LST and above 30 microg/dL on the HST can reliably predict the functional status of the hypothalamic-pituitaryadrenal axis in chronic secondary AI. Values between these cutoff points may necessitate further assessment with the OMT or ITT based on clinical suspicion. CONCLUSION We recommend a 3-step diagnostic approach, with the first 2 steps performed together-starting with the 8 AM basal cortisol determination in conjunction with either the LST (preferably) or the HST. In cases of an indeterminate response coupled with a strong clinical suspicion, the final step should be definitive testing with the OMT or ITT.

MELD-Na as a prognostic indicator of 30- and 90-day mortality in patients with end-stage liver disease after creation of transjugular intrahepatic portosystemic shunt.

Previous studies have shown that the Model for End-Stage Liver Disease (MELD) score is superior to other liver disease scoring systems to establish optimal candidates for transjugular intrahepatic portosystemic shunt (TIPS) procedure and liver transplantation. Our aim was to compare MELD-Na score with MELD score as a predictor of 30-day as well as 90-day mortality for individuals with end-stage liver disease (ESLD) after creation of TIPS. We performed a chart review on cirrhotic patients who underwent TIPS procedure and documented presence and severity of ascites and hepatic encephalopathy, patient laboratory values, and results from TIPS procedures. We compared continuous variables by Student’s t-test for independent samples and categorical variables by &khgr;2-test(s). In non-normal distributions, a nonparametric test was used. We performed a logistic regression to determine the effects of several variables and analyzed variable predictors of likelihood of death within 30 and 90 days of TIPS procedure. Of the six predictor variables, only MELD-Na score was a statistically significant predictor of 30- and 90-day mortality following TIPS procedure for ESLD (P=0.028). For each one point increase in MELD-Na score, the odds of death increased by 1.15 times [95% confidence interval (1.02–1.30), P=0.28]. Since hyponatremia may be associated with poor prognostic features of overall health, its incorporation into the MELD scoring system to predict mortality in ESLD after creation of TIPS serves a useful purpose. Our single-center experience suggests that the MELD-Na score is the most effective predictor of survival after TIPS creation.

Metabolic disease and shift work: Is there an association? An analysis of NHANES data for 2007–2008

Previous epidemiological studies have shown that shift work is associated with higher levels of obesity and diabetes, possibly related to physiological maladaptation as a direct result of sleeping and eating at abnormal circadian times.1 In a previously performed cross-sectional study, shift work was associated with higher levels of triglycerides, lower levels of high-density lipoprotein cholesterol, and higher odds of metabolic syndrome in a multiple logistic regression analysis (OR 2.4; 95% CI 1.1 to 5.0).2 We performed an analysis of the cross-sectional NHANES data3 for 2007–2008 and compared the different metabolic parameters between regular daytime workers and shift workers. Shift workers included …

Poor quality of life scores in persons with higher A1Cs in type 2 diabetes.

Although quality of life scores are lower in patients with type 2 diabetes, direct association of quality of life with various metabolic outcomes has not been well studied. The Audit of Diabetes Dependent Quality of Life (ADDQOL) was designed to measure individuals’ perceptions of the impact of diabetes on their quality of life [1]. Our study attempts to quantify the relationship between the ADDQOL questionnaire scores and the degree of control of metabolic parameters in type 2 diabetes patients. DYNAMIC is an NIH funded randomized controlled trial to evaluate the use of Nurse Case Management (NCM) with motivational interviewing to improve outcomes in the behaviors and metabolic parameters of high risk type 2 diabetes [2]. Along with metabolic parameters, patient’s psychological status has been measured by the ADDQOL. In DYNAMIC, 549 patients with type 2 diabetes from 11 primary care clinics with either A1C > 8.5 mg/dl, BP > 140/90 mmHg and/or LDL > 130 mg/dl had been recruited and randomized to receive either NCM or usual care. We performed linear regression on the baseline data to examine the impact of A1C, LDL, HDL, age, systolic blood pressure (SBP) and weight on the quality of life measured by ADDQOL scores. We examined the interaction between age, weight and SBP. The baseline descriptive data was as follows (mean SD): age (57.9 11.4 years), weight (209.5 57.2 lbs). Patients had elevated A1C (8.4 2.15 mg/dl), Systolic BP (137 19.3 mmHg) and LDL (114 37.4 mg/dl). Overall, patients were depressed as measured by the CES-D scores (CES-D = 14.8 15.0) and had an extremely negative quality of life (ADDQOL = 0.989). In the regression model, significant predictors of lower quality of life ADDQOL scores were A1C and age. HDL, LDL and Triglycerides were not predictive of ADDQOL scores. In the stepwise regression model, A1C emerged as a negative predictor of ADDQOL scores (correlation co-efficient: 0.843 0.119, p < 0.001) while age was a positive predictor with a small but significant effect (co-efficient 0.123 0.03, p < 0.003). There was interaction between age and systolic blood pressure and A1c and weight. The model was able to explain a significant part of the variability in ADDQOL scores (adjusted r = 0.23). Our cross sectional study showed that diabetes control is a significant negative predictor of quality of life measured by the ADDQOL. Inability to assess for diabetes related complications and incorporate that into the regression model is a significant limitation of our study.

Role of adipokines and inflammatory markers in postmenopausal hypertension

BACKGROUND The role of inflammatory markers and adipokines contributing to the development of postmenopausal hypertension, has not been established. The aim of our study was to assess the complex association between blood pressure, obesity, menopausal status, adipokines and inflammatory mediators in postmenopausal women. METHODS We recruited 38 women seen at our Endocrinology Clinic and collected anthropometric measures and blood pressure and obtained serum samples for inflammatory markers and adipokine levels. Out of 38 women, 23 (60%) were postmenopausal. RESULTS In the pre-menopausal and postmenopausal women, there were no significant differences in measured adipokines and inflammatory markers based on hypertensive status. When obesity was eliminated, significantly higher levels of EGF, IL-8, MCP1 and TNF-α and lower levels of IL-1α and IL-3 were observed in the postmenopausal group (P<0.05). Women with higher waist-to-hip ratio (WHR) had a significant trend towards lower adiponectin levels as compared to those with lower WHR (P=0.014 and P=0.04, respectively). CONCLUSIONS There was a significant difference in pro-inflammatory markers in non-obese, pre- and post-menopausal women. These higher inflammatory markers might play a role in the development of post-menopausal hypertension.

Unilateral Submandibular Gland Atrophy and Sialolithiasis Diagnosed on 99mTc-MIBI SPECT/CT in a Patient With Primary Hyperparathyroidism

A variety of sequelae of elevated calcium levels are encountered in patients with underlying primary hyperparathyroidism, including stone formation such as calculi in the urinary tract and sialoliths in the salivary glands and ducts. We present a case of a 54-year-old woman with fatigue, myalgia, and poor concentration who was found to have hypercalcemia (corrected calcium, 11.2 mg/dL) and elevated parathyroid hormone level (112 pg/mL), laboratory values consistent with primary hyperparathyroidism. She underwent evaluation with a Tc-MIBI parathyroid SPECT scan that included x-ray CT acquisitions for anatomical localization and attenuation correction.

Femoral Neck Bone Mineral Density in Persons Over 50 Years Performing Shiftwork: An Epidemiological Study.

Objective: Shiftwork has been associated with bone loss due to hormonal fluctuations. Our aim was to assess the femoral neck bone mineral density and content in persons over 50 years performing shiftwork. Methods: We performed analysis on the femoral neck bone mineral parameters in persons over age 50 years from the National Health and Nutrition Examination Survey cross-sectional data for 2010 to 2011 in regular and shiftworkers. We also assessed the degree of moderate physical activity and smoking in both groups. Results: Middle-aged men performing shiftwork had significantly higher total femur bone mineral content (37.33 ± 11.00 vs 34.09 ± 10.45, P = 0.01) and femoral neck bone mineral content (4.57 ± 1.07 vs 4.29 ± 1.0, P = 0.03). This difference was not seen in middle aged women. Conclusions: Shiftwork does not seem to affect bone mineral density in those performing moderate physical activity.