A Case of Oliguric Acute Renal Failure Caused by Acetazolamide / 대한내과학회지

Acetazolamide is a carbonic anhydrase inhibitor commonly used to treat glaucoma. It can cause metabolic acidosis and renal failure in the elderly and patients with chronic renal insufficiency. We report oliguric acute renal failure (ARF) caused by a conventional dose of acetazolamide for glaucoma in a patient with normal renal function. A 56-year-old woman with 20-year history of diabetes had general weakness, decreased urine output, nausea, and vomiting for 3 days. For the past 2 weeks, her glaucoma had been treated with acetazolamide. Blood-gas analysis showed pH 7.02, PCO2 27 mmHg, PO2 135 mmHg, and HCO3- 7.0 mmol/L. Her BUN was 65 mg/dL and creatinine, 9.1 mg/dL. She recovered after hemodialysis and hydration. Acetazolamide may cause severe ARF, even in patients with normal renal function, suggesting the importance of careful monitoring of renal function in patients taking acetazolamide.

Regulation of Inhibitors of Differentiation Family Proteins by Thyroid-Stimulating Hormone in FRTL-5 Thyroid Cells

Members of the inhibitors of differentiation (Id) family of helix-loop-helix (HLH) proteins are known to play important roles in the proliferation and differentiation of many cell types. Thyroid-stimulating hormone (TSH) regulates proliferation and differentiation by activating TSH receptor (TSHR) in thyrocytes. In this study, we found that Id2, one of the Id family proteins, is a major target for regulation by TSH in FRTL-5 thyroid cells. TSH rapidly increases the Id2 mRNA level in FRTL-5 thyroid cells but the Id2 protein showed biphasic regulatory patterns, being transiently reduced and subsequently induced by TSH treatment. Transient reduction of Id2 protein was noted within 2 hr of TSH treatment and was mediated by proteasomal degradation. Moreover, reduced Id2 expression correlated with the activity of the phosphatidylinositol 3 kinase pathway, which is activated by TSH. Although TSH increases the activity of the Id2 promoter, TSH-induced activation of this promoter was independent of c-Myc. Id2 did not alter TTF-1- and Pax-8-mediated effects on the regulation of the Tg promoter. Thus, in summary, we found that TSH regulates Id2 expression, but that Id2 does not alter the expression of thyroid-specific genes, such as Tg, in FRTL-5 thyroid cells.

The Adequacy of Ultrasound-Guided Fine Needle Aspiration in Thyroid Nodules / 대한내분비학회지

BACKGROUND: Fine needle aspiration(FNA) is an accurate and safe method for the diagnosis of thyroid nodules. One of the limitations of FNA is the variable rate of unsatisfactory specimens, especially in small sized, deep seated or complex cystic nodules. To overcome this problem, ultrasound-guided FNA(US-FNA) has been widely used. In this study, the adequacy of cytologic specimens by US-FNA was compared with that of conventional palpation-guided FNA(P-FNA). METHODS: The medical records of all patients who were engaged in FNA due to thyroid nodules at Chungnam National University Hospital from January 2003 to July 2004 were retrospectively examined. The US-FNA and P-FNA were performed in 114 and 185 patients, respectively. RESULTS: Comparison of the adequacy of the two techniques in providing sufficient material for the cytologic diagnosis showed that specimens in 24(13.0%) and 6(5.3%) patients collected by P-FNA and US-FNA, respectively, were unsatisfactory(P=0.031). A total of 23 patients underwent thyroid surgery due to strong suspicion of malignancy at cytologic finding and/or on clinical judgement. Seventeen patients belonged to the P-FNA group and 6 patients to the US-FNA group. In the P-FNA group, a histologic diagnosis revealed two false-negative cytologic findings, but no false-negative findings were found in the US-FNA group. CONCLUSION: Compared with P-FNA, US-FNA may reduce the possibility of unsatisfactory cytologic specimens and the rate of false-negative diagnosis, and may improve the diagnostic accuracy in investigating thyroid nodules

The Relationship between the BRAF Mutations in Thyroid Papillary Carcinomas and the Prognostic Factors / 대한내분비학회지

BACKGROUND: Thyroid cancers account for about 1% of all human malignancies, with papillary thyroid carcinomas being the most common istotype. Several investigators have recently identified the most common BRAF mutation, the T1796A transversion mutation, in 29~69% of papillary thyroid cancers. The BRAF mutation has been demonstrated as a novel prognostic biomarker for the prediction of poor clinicopathological outcomes, such as increased incidence of extrathyroid invasion and distant metastasis of the tumor. In this study, we investigated the prevalence of the BRAF mutation of thyroid tissues obtained by a thyroidectomy, and its correlation with the clinicopathological outcomes. METHODS: We studied 36 thyroid tissues obtained from 24 women and 12 men by thyroidectomies, including 30 papillary carcinomas, 3 follicular carcinomas, 1 medullary carcinoma and 2 nodular hyperplasia. The mutation was sought in all specimens using DNA sequencing. RESULTS: We studied the BRAF exon 15 T1796A in these 36 thyroid tissues. The mean age at surgery was 46.6, ranging from 18 to 72 years, with a median tumor size of 2.79, ranging from 1.5 to 4.5cm. At the time of diagnosis, 27 of the 34 patients presented with some kind of extrathyroidal invasion of the tumor, and 16 had lymph node metastases. 16, 2 and 16 patients were in stages I, II and III, respectively. There was no distant metastasis. A missense mutation was found at T1796A in exon 15 in 21 of the 30 papillary carcinomas(70%). The other thyroid diseases, including the 3 follicular carcinomas, 1 medullary carcinoma and 2 nodular hyperplasia show no exon 15 T1759A transversion mutation. No statistically significant association was found between the BRAF mutations and clinicopathological characteristics of papillary carcinomas. CONCLUSION: The BRAF mutation is a important genetic alteration, with a high prevalence in papillary thyroid carcinomas. However, there was no significant association between the BRAF mutation and any of the clinicopathological factors. Further, large scale studies will be needed to evaluate the correlation between the BRAF mutation and the clinicopathological factors

The Relationship between the BRAF Mutations in Thyroid Papillary Carcinomas and the Prognostic Factors / 대한내분비학회지

BACKGROUND: Thyroid cancers account for about 1% of all human malignancies, with papillary thyroid carcinomas being the most common istotype. Several investigators have recently identified the most common BRAF mutation, the T1796A transversion mutation, in 29~69% of papillary thyroid cancers. The BRAF mutation has been demonstrated as a novel prognostic biomarker for the prediction of poor clinicopathological outcomes, such as increased incidence of extrathyroid invasion and distant metastasis of the tumor. In this study, we investigated the prevalence of the BRAF mutation of thyroid tissues obtained by a thyroidectomy, and its correlation with the clinicopathological outcomes. METHODS: We studied 36 thyroid tissues obtained from 24 women and 12 men by thyroidectomies, including 30 papillary carcinomas, 3 follicular carcinomas, 1 medullary carcinoma and 2 nodular hyperplasia. The mutation was sought in all specimens using DNA sequencing. RESULTS: We studied the BRAF exon 15 T1796A in these 36 thyroid tissues. The mean age at surgery was 46.6, ranging from 18 to 72 years, with a median tumor size of 2.79, ranging from 1.5 to 4.5cm. At the time of diagnosis, 27 of the 34 patients presented with some kind of extrathyroidal invasion of the tumor, and 16 had lymph node metastases. 16, 2 and 16 patients were in stages I, II and III, respectively. There was no distant metastasis. A missense mutation was found at T1796A in exon 15 in 21 of the 30 papillary carcinomas(70%). The other thyroid diseases, including the 3 follicular carcinomas, 1 medullary carcinoma and 2 nodular hyperplasia show no exon 15 T1759A transversion mutation. No statistically significant association was found between the BRAF mutations and clinicopathological characteristics of papillary carcinomas. CONCLUSION: The BRAF mutation is a important genetic alteration, with a high prevalence in papillary thyroid carcinomas. However, there was no significant association between the BRAF mutation and any of the clinicopathological factors. Further, large scale studies will be needed to evaluate the correlation between the BRAF mutation and the clinicopathological factors

Lymphocytic Hypophysitis with Diabetes Insipidus: Improvement by Methylprednisolone Pulse Therapy

Lymphocytic hypophysitis is a rare inflammatory disorder in the pituitary gland. The lesion is usually confined to the adenohypophysis. Although the involvement of the posterior pituitary gland or the stalk is rare, such patients with diabetes insipidus have been reported. Surgery has been used to make the definitive diagnosis. Recent studies suggest, however, that the pathologic diagnosis may not be necessary always. We reported a case of Lymphocytic hypophysitis managed by methylprednisolone pulse therapy. A 50-year-old premenopausal woman with Lymphocytic hypophysitis and diabetes insipidus was treated with methylprednisolone pulse therapy. Her adenopituitary lesion disappeared and the diabetes insipidus resolved. The optimal management for patients with lymphocytic hypophysitis may be the high index of the suspicion prior to the extensive surgical resection. In addition, methylprednisolone pulse therapy may improve the clinical and MRI findings.