BACKGROUND/AIMS: The diagnostic accuracy of thyroid dysfunctions is primarily affected by the validity of the reference interval for serum thyroid-stimulating hormone (TSH). Thus, the present study aimed to establish a reference interval for TSH using a normal Korean population. METHODS: This study included 19,465 subjects who were recruited after undergoing routine health check-ups. Subjects with overt thyroid disease, a prior history of thyroid disease, or a family history of thyroid cancer were excluded from the present analyses. The reference range for serum TSH was evaluated in a normal Korean reference population which was defined according to criteria based on the guidelines of the National Academy of Clinical Biochemistry, ultrasound (US) findings, and smoking status. Sex and age were also taken into consideration when evaluating the distribution of serum TSH levels in different groups. RESULTS: In the presence of positive anti-thyroid peroxidase antibodies or abnormal US findings, the central 95 percentile interval of the serum TSH levels was widened. Additionally, the distribution of serum TSH levels shifted toward lower values in the current smokers group. The reference interval for TSH obtained using a normal Korean reference population was 0.73 to 7.06 mIU/L. The serum TSH levels were higher in females than in males in all groups, and there were no age-dependent shifts. CONCLUSIONS: The present findings demonstrate that the serum TSH reference interval in a normal Korean reference population was higher than that in other countries. This result suggests that the upper and lower limits of the TSH reference interval, which was previously defined by studies from Western countries, should be raised for Korean populations.
Adult ; Age Factors ; Aged ; Biomarkers/blood ; Case-Control Studies ; Cross-Sectional Studies ; Female ; Humans ; Male ; Middle Aged ; Predictive Value of Tests ; Reference Values ; Republic of Korea ; Sex Factors ; Smoking/blood ; Thyroid Diseases/blood/*diagnosis/ultrasonography ; Thyroid Function Tests/*standards ; Thyroid Gland/*metabolism/*ultrasonography ; Thyrotropin/*blood ; Time Factors ; Young Adult

BACKGROUND: Recently, the diagnosis of non-alcoholic fatty liver disease (NAFLD) has been made more frequently, as the use of ultrasonography on health screening has been on the rise. The aim of this study was to elucidate the relationship between NAFLD and the metabolic syndrome defined by NCEP-ATP III criteria. METHODS: A total of 1,675 subjects, who attended for routine physical check?ups, were screened. Among those, 401 subjects were selected after excluding the subjects with either significant alcohol consumption, evidence of viral or toxic hepatitis, significant liver or renal dysfunction, or overt thyroid disease. NAFLD was diagnosed if the subjects had a "bright liver" on ultrasonographic examination. The diagnosis of metabolic syndrome was made according to the criteria of NCEP-ATP III established in 2001. RESULTS: The prevalence of NAFLD was 27.2%. Blood pressure, body weight, body mass index, waist circumference, and serum levels of total cholesterol, triglyceride, fasting glucose and liver enzymes were higher among the subjects with NAFLD than the control. The prevalence of obesity, IFG/DM, dyslipidemia and hypertension was higher in the NAFLD group. The prevalence of the metabolic syndrome was 19.2%, which was higher in the NAFLD group than the control group. The odds ratio of NAFLD for the metabolic syndrome was 6.458 (95% C.I. 3.178~13.124). CONCLUSION: NAFLD was closely associated with the metabolic syndrome regardless of the presence of obesity.
Alcohol Drinking ; Blood Pressure ; Body Mass Index ; Body Weight ; Cholesterol ; Diagnosis ; Drug-Induced Liver Injury ; Dyslipidemias ; Fasting ; Fatty Liver* ; Glucose ; Hypertension ; Liver ; Mass Screening ; Obesity ; Odds Ratio ; Prevalence ; Thyroid Diseases ; Triglycerides ; Ultrasonography ; Waist Circumference

Neck mass can be frequently encountered in pediatric patients. Most neck mass in pediatric patients are either inflammatory lesions or benign tumors but their differential diagnoses are not always easy. We must not forget the study results that a considerable portion of pediatric neck mass constitutes malignant tumors. Generally neck mass can be divided into inflammatory, developmental (congenital), and tumorous lesions. Developmental neck mass are generally thyroglossal duct cyst, branchial cleft cyst, dermoid cyst, vascular malformation, or hemangioma. Manifestations of inflammatory neck mass are reactive cervical lymphadenopathy, infectious lymphadenitis (viral or bacterial), mycobacterial cervical lymphadenopathy, or Kawasaki disease. The more uncommonly found pediatric malignant neck mass are lymphoma, rhabdomyosarcoma, or thyroid carcinoma. For the diagnosis of pediatric neck mass complete blood count, purified protein derivative test for tuberculosis, and measurement of titers for Epstein-Barr virus are required and in special cases, infectious diagnostic panels for cat-scratch disease, cytomegalovirus, human immunodeficiency virus, or toxoplasmosis may be needed. Ultrasonography is the most convenient and feasible diagnostic method in differentiating various neck mass. Computed tomography is performed when identifying the anatomical aspects of the neck mass or where deep neck infection or retropharyngeal abscess is suspected. Surgical management for congenital neck mass is recommended to prevent secondary infection or various complications following size increase. Most pediatric neck mass originate from bacterial lymphadenitis and antibacterial therapy is considered first line of conservative treatment. However if the neck mass is either over 2 cm in size without any evidence of inflammation, firm or fixed to surrounding tissue, accompanied by B symptoms, unresponsive to initial antibacterial therapy or over 4 weeks of conservative management, or considered keep growing for over 2 weeks, one must suspect the possibility of malignancy and must consult a head and neck specialist for further detailed evaluation.
Blood Cell Count ; Branchioma ; Cat-Scratch Disease ; Coinfection ; Cytomegalovirus ; Dermoid Cyst ; Diagnosis ; Diagnosis, Differential ; Head ; Hemangioma ; Herpesvirus 4, Human ; HIV ; Humans ; Inflammation ; Lymphadenitis ; Lymphatic Diseases ; Lymphoma ; Mucocutaneous Lymph Node Syndrome ; Neck* ; Retropharyngeal Abscess ; Rhabdomyosarcoma ; Specialization ; Thyroglossal Cyst ; Thyroid Neoplasms ; Toxoplasmosis ; Tuberculosis ; Ultrasonography ; Vascular Malformations