Results of the Dyslipidemia International Study (DYSIS)-Middle East: clinical perspective on the prevalence and characteristics of lipid abnormalities in the setting of chronic statin treatment.

BACKGROUND: Therapeutic intervention with low-density lipoprotein cholesterol-lowering agents known as statins has been demonstrated to reduce cardiovascular risk. However, many patients on statin treatment have persistent dyslipidemia and remain at a high risk of cardiovascular disease. Therefore, the objective of this study was to assess the frequency of lipid abnormalities in patients receiving chronic statin treatment. METHODS: As part of an international, cross-sectional, observational study, DYSIS-Middle East enrolled 2,182 patients in the United Arab Emirates (UAE), Saudi Arabia, Lebanon and Jordan. All patients were over 45 years of age and had been on statin treatment for at least three months. Data on demographics, lipid parameters and cardiovascular risk profile were recorded. Cardiovascular risk was defined according the guidelines of the European Society of Cardiology. RESULTS: The majority of patients (82.6%) were classified as being at very high risk of cardiovascular events, and 61.8% of all patients did not attain LDL-C target levels. Low high-density lipoprotein cholesterol levels and elevated triglyceride levels were noted in 55.5% and 48.5% of patients, respectively. Multivariate logistical regression modeling indicated that factors independently associated with LDL-C levels not being at goal were lifestyle choices, diabetes mellitus, ischemic heart disease, and blood pressure ≥ 140/90 mmHg. CONCLUSIONS: Almost two-thirds of statin-treated patients in the United Arab Emirates, Saudi Arabia, Lebanon and Jordan had inadequately controlled lipid levels. More comprehensive surveillance, awareness and treatment regimens, as well as modification of lifestyle choices, is necessary to halt the rise in cardiovascular disease-related mortality.

Diagnostic accuracy of high-resolution neck ultrasonography in the follow-up of differentiated thyroid cancer: a prospective study.

OBJECTIVE: To conduct a prospective study of the diagnostic value of features of cervical lymph nodes (large size, central location, abnormal shape, cystic changes, calcifications, and loss of echogenic hilum), assessed by neck ultrasonography (US), in patients scheduled for surgical treatment of persistent or recurrent differentiated thyroid cancer. METHODS: We studied 152 US abnormalities in 42 patients (median age, 38.5 years) who had undergone one or more neck operations, with or without radioiodine therapy, but continued to have persistent or recurrent disease, which was confirmed by fine-needle aspiration. Another surgical procedure was planned for these patients. On the day of operation, patients underwent a detailed US neck examination by an experienced radiologist. US abnormalities were plotted on a standard diagram of the neck and given specific numbers to help track them during surgical intervention and histopathologic examinations. The US features were compared with the final histopathologic diagnosis. RESULTS: Of 152 US abnormalities, 127 involved cervical lymph nodes and 25 involved other types of tissue. In univariate analysis, size, absent echogenic hilum, cystic changes, calcifications, and central location (medial to the sternomastoid muscle) of cervical lymph nodes were significantly associated with the presence of metastatic involvement. In multivariate analysis, only central location (odds ratio, 4.07; 95% confidence interval [CI], 1.64 to 10.10) and size (odds ratio, 5.14; 95% CI, 1.64 to 16.06) remained significant. The receiver operating characteristic curve for the size of lymph nodes showed a large area under the curve of 0.77 (95% CI, 0.68 to 0.85), and a size of 7.5 mm showed the highest sensitivity and specificity. CONCLUSION: Size and central location of cervical lymph nodes assessed by US during follow-up of patients with differentiated thyroid cancer were the most important predictors of presence of metastatic disease.

The hook effect in prolactin immunoassays.

We describe a young female patient with giant invasive sellar and suprasellar tumor and modest elevation of prolactin to 165 ng/ml (normal range 3-29). A diagnosis was made of non functional pituitary adenoma with stalk effect, causing moderate prolactin elevation. A surgery for the removal of the tumor was advised but the patient declined. Treatment with a dopamine agonist was not offered. The patient presented 2 years later with deterioration of her vision and serum prolactin of >16000 ng/ml. Debulking transsphenoidal surgery was performed. The staining of tissue confirmed prolactinoma. Medical treatment with bromocriptine was initiated. We believe that the discrepancy between the 2 values of serum prolactin, is most probably caused by a hook effect in the initial prolactin assay. The mechanism of the hook effect and its occurrence with prolactin immunoassays and methods to eliminate this effect is discussed. Hook effect needs to be suspected in every patient with a giant pituitary or parasellar mass and serum prolactin <200 ng/ml. Assaying a diluted serum will usually unmask this phenomenon and allow accurate diagnosis and management.