Smaller Mean LDL Particle Size and Higher Proportion of Small Dense LDL in Korean Type 2 Diabetic Patients

BACKGROUND: Small dense low density lipoprotein (sdLDL) has recently emerged as an important risk factor of coronary heart disease. METHODS: The mean LDL particle size was measured in 203 patients with type 2 diabetes mellitus (T2DM) and 212 matched subjects without diabetes using polyacrylamide tube gel electrophoresis. Major vascular complications were defined as stroke, angiographically-documented coronary artery disease or a myocardial infarction. Peripheral vascular stenosis, carotid artery stenosis (> or =50% in diameter) or carotid artery plaque were considered minor vascular complications. Overall vascular complications included both major and minor vascular complications. RESULTS: Diabetic patients had significantly smaller mean-LDL particle size (26.32 nm vs. 26.49 nm) and a higher percentage of sdLDL to total LDL compared to those of subjects without diabetes (21.39% vs. 6.34%). The independent predictors of sdLDL in this study were serum triglyceride level and body mass index (odds ratio [OR], 1.020 with P<0.001 and OR 1.152 with P<0.027, respectively). However, no significant correlations were found between sdLDL and major vascular complications (P=0.342), minor vascular complications (P=0.573) or overall vascular complications (P=0.262) in diabetic subjects. CONCLUSION: Diabetic patients had a smaller mean-LDL particle size and higher proportion of sdLDL compared to those of subjects without diabetes. Obese diabetic patients with hypertriglyceridemia have an increased risk for atherogenic small dense LDL. However, we could not verify an association between LDL particle size and vascular complications in this study.

Autosomal Dominant Hypocalcemia Caused by an Activating Mutation of the Calcium-Sensing Receptor Gene: The First Case Report in Korea

Hypoparathyroidism is an abnormality of calcium metabolism characterized by low serum levels of parathyroid hormone in spite of hypocalcemia. The causes of hypoparathyroidism are numerous. Activating mutations in the calcium-sensing receptor (CaSR) gene are well-known causes of familial isolated hypoparathyroidism, also known as autosomal dominant hypocalcemia (ADH). Here we describe members of a Korean family with a heterozygous Pro221Leu mutation causing ADH. This case is the first report in Korea.

A Case of Resistance to Thyroid Hormone with Thyroid Cancer

Resistance to thyroid hormone (RTH) is an autosomal dominant hereditary disorder that is difficult to diagnose because of its rarity and variable clinical features. The magnitude of RTH is caused by mutations in the thyroid hormone receptor beta (TRbeta) gene. We recently treated a 38-yr-old woman with RTH who had incidental papillary thyroid carcinoma. She presented with goiter and displayed elevated thyroid hormone levels with an unsuppressed TSH. She was determined to harbor a missense mutation of M310T in exon 9 of the TRbeta gene, and diagnosed with generalized RTH. This mutation has not yet been reported in Korea. RTH is very rare and easily overlooked, but should be considered in patients who present with goiter and elevated thyroid hormone levels with an unsuppressed TSH. The association between thyroid cancer and RTH needs further study.

Sustained Maintenance of Normal Insulin-like Growth Factor-I during Pregnancy and Successful Delivery in an Acromegalic Patient with Octreotide-LAR(R) Treatment

We report here on a 34-year-old Korean woman with active acromegaly and who received Octreotide-LAR(R) for 12 months following transsphenoidal pituitary surgery. During Octreotide-LAR(R) treatment, the clinical improvement was paralleled with the decrease of the growth hormone levels to 1.1 ng/mL and the insulin-like growth factor-I (IGF-I) levels to 345.5 ng/mL. Octreotide-LAR(R) was discontinued when the patient was found to be at the 12th week of pregnancy. During pregnancy, the patient experienced clinical well-being and she maintained her IGF-I levels within the normal range for her age-matched despite discontinuation of Octreotide-LAR(R) treatment at early gestation. She delivered a full-term healthy male infant. The serum IGF-I levels of the patient increased progressively increased after delivery. This report describes a successful pregnancy in an acromegalic woman who was exposed to Octreotide-LAR(R) during the early gestational period. She and who showed an unexpected pattern of persistently normal IGF-I levels through the pregnancy despite discontinuation of Octreotide-LAR(R) therapy.