ACTA ENDOCRINOLOGICA (BUC)

Background. Insulin resistance is routinely measured by homeostasis model assessment of insulin resistance (HOMA-IR).Positron emission tomography of 18F-fluorodeoxyglucose combined with computed tomography (18F-FDG PET/CT) is a valuable assessment tool for patients with cancer or staging tumors. 18F-FDG PET/CT imaging can also be utilised to detect the metabolic activity of glucose in the adipose tissue, liver and muscles. The aim of this study was to determine insulin sensitivity in the liver, muscle visceral adipose and subcutaneous adipose tissue separately via18F-FDG PET/CT. Materials and method. Sixty three adult patients who underwent whole body 18F-FDG PET/CT scanning for clinical purposes (diagnosis or staging of cancer) between July and August of 2016 were included in the study. Patients were divided into two groups according to their BMI (Group 1: BMI<25kg/m2, Group 2: BMI>25kg/ m2). HOMA-IR,fasting glucose,insulin, triglycerides, total cholesterol, HDL levels were measured. We calculated SUV as the tissue activity of the ROI (MBq/g)/(injected dose [MBq]/ body weight [g]) on PET images and measured the maximum SUVs (SUVmax) of visceral adipose tissue (VAT) and subcutaneous adipose tissue (SAT),liver and rectus muscle ROIs (2 cm). SUV corrected by blood glucose level (SUVgluc) was calculated as SUVmax×blood glucose level/100. Student-t test, Chi-square test and Pearson correlation test were used for statistical analysis. Results. Mean glucose,insulin,HOMA-IR levels of the group-2 were statistically higher than of group-1. Muscle SUVmax and liver SUVmax of group-1 were statistically higher than of group-2. Muscle SUVgluc of group-1 was statistically higher than of group-2. HOMA-IR was negatively correlated with both SUVmax(r=-0.340, p=0.01) and muscle SUVmax(r=-0.373, p=0.005) Conclusion. 18F-FDG PET/CT has shown that the muscle tissue maximum FDG uptake was lower in the insulin resistance group. Therefore, 18-FDG PET/CT could be a valuable tool for diagnosing insulin resistance.

Background. The modern management of phenylketonuria (PKU) consists of generalized newborn screening (NBS) for hyperphenylalaninemia (HPA), confirmation of HPA in children detected in the NBS, introduction of dietary treatment in the first weeks of life, followed by monitoring the treatment of PKU for decades to maintain phenylalaninemia within the limits that will not affect the brain. The present study aimed to evaluate the usefulness of two chromatographic methodologies for determination of plasma Phe level in the routine management of PKU: the two dimensional thin layer chromatography (2D - TLC) and the high performance liquid chromatography (HPLC) procedures, respectively. Material and Methods. Samples of blood from 23 children with HPA detected by neonatal screening or with confirmed PKU who received treatment by low-Phe diet were analyzed to estimate the plasma Phe level by the two chromatographic procedures. Results. In case of three subjects the very low concentrations of plasma Phe could not be detected by the 2D - TLC methodology, since the spot was not visible on the chromatogram. In four patients the differences between the values of plasma Phe determined by the two methodologies are not statistically significant, while in fifteen subjects the differences are highly statistically significant. This is due to the greater errors that appear in the case of 2D - TLC methodology. In the range of concentrations of plasma Phe higher than 360 μmol/L (which is the cut-off value for HPA), although in four cases there were statistically significant differences in the level of plasma Phe determined by the two methodologies, the value obtained by the 2D - TLC methodology was high enough to influence the decision of changing the diet so that HPA is kept under control. In addition, the intense spot of Phe on the 2D - TLC chromatogram may be detected even by un unexperienced laboratory specialist. Conclusion. The HPLC procedure for measurement of plasma Phe level is very suitable to be used in the routine management of PKU. The 2D - TLC procedure may be accompanied by relatively high errors; however, it detects patients with severe PKU.

Background. Paraganglioma develop from embryological neural crest cells from the base of the skull, mediastinum, retroperitoneum, urinary bladder and scrotum. The most common location of the retroperitoneal form is situated between the aorta and vena cava, at the level of left renal vein, or more distally, to the aortic bifurcation. The care of patients with paraganglioma is a challenge for many physicians and surgeons because of its clinical features and therapeutic implications. Case presentation. We report the case of a 22-years old female patient with symptomatic retroperitoneal paraganglioma who was successfully treated with complete surgical excision. The pathological report confirmed the presence of chromaffin tumours. Postoperative care was uneventful, the patient being discharged after 10 days. Follow-up evaluation showed no recurrence after 4 years. Conclusion. Although a very rare condition, retroperitoneal paraganglioma has to be considered in the differential diagnosis of retroperitoneal tumours. Complete surgical resection is crucial for treatment and histological assessment as these tumours are potentially curable if they are diagnosed correctly. In our experience, the best surgical approach is open surgical excision for large masses located in the interaortocaval region, with a clear operatory field and good control over the major blood vessels. Follow-up is strongly recommended.