Kyong Young Kim

Delayed Surgery for Parathyroid Adenoma Misdiagnosed as a Thyroid Nodule and Treated with Radiofrequency Ablation

Primary hyperparathyroidism occurs as a result of isolated parathyroid adenoma in 80% to 85% of all cases. A 99mtechnetium (99mTc) sestamibi scan or neck ultrasonography is used to localize the neoplasm prior to surgical intervention. A 53-year-old female was referred for the exclusion of metabolic bone disease. She presented with low back pain that had persisted for the past 6 months and elevated serum alkaline phosphatase (1,253 IU/L). Four years previously, she had been diagnosed at a local hospital with a 2.3-cm thyroid nodule, which was determined to be pathologically benign. Radiofrequency ablation was performed at the same hospital because the nodule was still growing during the follow-up period 2 years before the visit to our hospital, and the procedure was unsuccessful in reducing the size of the nodule. The results of the laboratory tests in our hospital were as follows: serum calcium, 14.6 mg/dL; phosphorus, 3.5 mg/dL; and intact parathyroid hormone (iPTH), 1,911 pg/mL. Neck ultrasonography and 99mTc sestamibi scan detected a 5-cm parathyroid neoplasm in the left lower lobe of the patients thyroid; left parathyroidectomy was performed. This case indicated that thyroid ultrasonographers and pathologists need to be experienced enough to differentiate a parathyroid neoplasm from a thyroid nodule; 99mTc sestamibi scan, serum calcium, and iPTH levels can help to establish the diagnosis of parathyroid neoplasm.

Optimal follow-up strategies for adrenal incidentalomas: reappraisal of the 2016 ESE-ENSAT guidelines in real clinical practice

OBJECTIVE Recently, the European Society of Endocrinology (ESE), in collaboration with the European Network for the Study of Adrenal Tumors (ENSAT), asserted that adrenal incidentalomas (AIs) <4 cm and ≤10 Hounsfield units (HU) do not require further follow-up imaging. To validate the clinical application of the follow-up strategies suggested by the 2016 ESE-ENSAT guidelines, we explored the clinical characteristics and natural course of AIs in a single center over 13 years. DESIGN AND METHODS This retrospective cohort study included a total of 1149 patients diagnosed with AIs between 2000 and 2013 in a single tertiary center. Hormonal examination and radiological evaluations were performed at the initial diagnosis of AI and during the follow-up according to the appropriate guidelines. RESULTS The mean age at diagnosis was 54.2 years, and the majority of AIs (68.0%) were nonfunctional lesions. Receiver operating curve analysis was used to discriminate malignant from benign lesions; the optimal cut-off value for mass size was 3.4 cm (sensitivity: 100%; specificity: 95.0%), and that for the pre-contrast HU was 19.9 (sensitivity: 100%; specificity: 67.4%). The majority of nonfunctional lesions did not change in size during the 4-year follow-up period. Applying a cut-off value of 1.8 μg/dL after a 1-mg overnight dexamethasone suppression test, 28.0% of all nonfunctional AIs progressed to autonomous cortisol secretion during the follow-up period. However, we observed no development of overt Cushings syndrome in the study. CONCLUSIONS We advocate that no follow-up imaging is required if the detected adrenal mass is <4 cm and has clear benign features. However, prospective studies with longer follow-up are needed to confirm the appropriate follow-up strategies.

Disentangling of Malignancy from Benign Pheochromocytomas/Paragangliomas

Objective Many malignant tumors initially appear benign but subsequently exhibit extensive metastases. Early identification of malignant pheochromocytomas and paragangliomas (PPGLs) before metastasis is important for improved prognosis. However, there are no robust prognostic indices of recurrence and malignancy. The aim of this study was to identify the clinical and histopathological factors that predict malignant PPGLs. Design Retrospective follow-up study. Methods In this study, we included 223 patients with pathologically confirmed PPGLs who were treated between 2000 and 2015 at the Seoul National University Hospital in South Korea. Results Of these patients, 29 were diagnosed with malignancy, 12 of whom presented with metastatic lesions at the initial diagnosis while 17 developed metastases during follow-up. Nineteen patients with recurrent PPGLs consisted of ones with malignant PPGLs (n = 17) and multifocal PPGLs (n = 2) who had VHL and RET mutations. The mean age at presentation for malignant PPGLs was significantly younger than that for benign PPGLs (43.0 vs. 49.0 years, respectively; p = 0.023). Tumor size was not a distinguishing factor between malignant and benign PPGLs (5.0 vs. 4.5 cm, respectively; p = 0.316) nor did it predict recurrence. Of 119 patients with available pheochromocytoma of adrenal gland scaled score (PASS) data, those with malignant PPGLs presented PASS values ≥4. Of 12 parameters of PASS, necrosis, capsular invasion, vascular invasion, cellular monotony, high mitosis, atypical mitotic figures, and nuclear hyperchromasia were significant predictors of malignancy. Conclusions Tumor size did not predict malignancy or recurrence of PPGLs. PPGL patients with characteristic pathologic findings and PASS ≥4 or germline mutations require close follow-up.

Improvement of Glycemic Control after Re-Emphasis of Lifestyle Modification in Type 2 Diabetic Patients Reluctant to Additional Medication

Purpose The aim of this study is to observe glycemic changes after emphasizing the importance of lifestyle modification in patients with mild or moderately uncontrolled type 2 diabetes. Materials and Methods We examined 51 type 2 diabetic patients with 7.0-9.0% hemoglobin A1c (HbA1c) who preferred to change their lifestyle rather than followed the recommendation of medication change. At the enrollment, the study subjects completed questionnaires about diet and exercise. After 3 months, HbA1c levels were determined and questionnaires on the change of lifestyle were accomplished. We divided the study subjects into 3 groups: improved (more than 0.3% decrease of HbA1c), aggravated (more than 0.3% increase of HbA1c) and not changed (-0.3% <HbA1c change <0.3%). Results Among the total 51 subjects, 18 patients (35.3%) showed the decreased levels of HbA1c after 3 months with mean change of -0.74±0.27%, and HbA1c values of 11 patients (21.5%) were less than 7%. In addition, the HbA1c level was significantly reduced in patients who reportedly followed the lifestyle modification such as diet and exercise for 3 months, compared with the one obtained from patients who refused this lifestyle change (p=0.002). Conclusion In this study, 35.3% of the patients with mild or moderately uncontrolled type 2 diabetes showed the significant improvement of HbA1c levels after 3 months by simply regulating their daily diet and exercise without change of medication. This suggests that the lifestyle modification is significantly associated with the improvement of glucose control.

Infectious Spondylitis with Bacteremia Caused by Roseomonas mucosa in an Immunocompetent Patient

Roseomonas are a gram-negative bacteria species that have been isolated from environmental sources. Human Roseomonas infections typically occur in immunocompromised patients, most commonly as catheter-related bloodstream infections. However, Roseomonas infections are rarely reported in immunocompetent hosts. We report what we believe to be the first case in Korea of infectious spondylitis with bacteremia due to Roseomonas mucosa in an immunocompetent patient who had undergone vertebroplasty for compression fractures of his thoracic and lumbar spine.

Comparisons of TBS and lumbar spine BMD in the associations with vertebral fractures according to the T-scores: A cross-sectional observation

Trabecular bone score (TBS) is a parameter of bone quality that has been shown to be related to vertebral fractures. This study aimed to analyze the difference in discriminatory power of TBS for vertebral fractures according to the bone mineral density (BMD) T-score. Areal BMD at the lumbar spine (LS, L1-L4), femur neck (FN) and total hip were assessed using dual x-ray absorptiometry (Discovery W, Hologic, Bedford, MA) in 929 women aged 50years or older. TBS was analyzed using iNsight software (Med-Imaps, Pessac, France). Vertebral fractures were identified on lateral X-ray films of the thoracic and lumbar spine using a semi-quantitative method. The study subjects consisted of 158 subjects (17.0%) with normal BMD, 461 (49.6%) with osteopenia and 310 (33.4%) with osteoporosis. The incident vertebral fractures were observed in 92 (9.9%) subjects, including 59 fractures in osteoporosis, 29 fractures in osteopenia, and only 4 fractures in normal BMD. We stratified study subjects into two groups according to their BMD T-scores, osteoporosis or osteopenia/normal BMD. The logistic regression model showed that LS BMD values per each 1 standard deviation (SD) decrease were significantly associated with increased risk of vertebral fracture in both osteoporosis and osteopenia/normal BMD group with stronger association in osteoporosis group. However, a TBS value that was lower by 1SD was significantly associated with vertebral fracture risk only in the osteopenia/normal BMD group. The TBS use in addition to FN BMD and age also showed significantly better discriminatory power for vertebral fracture only in the osteopenia/normal BMD group, but not osteoporosis group. In conclusion, TBS is significantly associated with vertebral fractures in subjects with osteopenia/normal BMD levels. Additional assessment of bone microarchitecture using TBS is better able to identify women at risk of fracture, in particular, those with relatively higher BMD.

Insulin Resistance and the Risk of Diabetes and Dysglycemia in Korean General Adult Population

Background Insulin resistance is a major pathogenic hallmark of impaired glucose metabolism. We assessed the accuracy of insulin resistance and cut-off values using homeostasis model assessment of insulin resistance (HOMA-IR) to classify type 2 diabetes mellitus (T2DM) and dysglycemia according to age and sex. Methods In this cross-sectional study, we analyzed 4,291 anti-diabetic drug-naïve adults (≥20 years) from the 6th Korea National Health and Nutrition Examination Survey in 2015. Metabolic syndrome (MetS) was defined by the modified National Cholesterol Education Program III guideline. Diagnosis of dysglycemia and T2DM were based on fasting glucose and glycosylated hemoglobin levels. The receiver operating characteristic curve and optimal cut-off values of HOMA-IR were assessed to identify T2DM/dysglycemia according to sex and were further analyzed by age. Results Sex differences were found in the association of MetS and the different MetS components with T2DM/dysglycemia. The overall optimal cut-off value of HOMA-IR for identifying dysglycemia was 1.6 in both sex. The cut-off values for T2DM were 2.87 in men and 2.36 in women. However, there are differences in diagnostic range of HOMA-IR to distinguish T2DM according to sex and age, and the accuracy of HOMA-IR in identifying T2DM gradually decreased with age especially in women. Conclusion Insulin resistance is closely associated with the risk for T2DM/dysglycemia. The accuracy of HOMA-IR levels is characterized by sex- and age-specific differences in identifying T2DM. In addition to insulin resistance index, insulin secretory function, and different MetS components should be considered in the detection of early T2DM, especially in elderly.

Are pregnancy, parity, menstruation and breastfeeding risk factors for thyroid cancer? Results from the Korea National Health and Nutrition Examination Survey, 2010-2015

It is unclear whether reproductive factors such as pregnancy, parity, menstruation, and breastfeeding are risk factors for thyroid cancer. The aim of this study was to evaluate the association of reproductive factors with thyroid cancer risk.