Mehtap Erkmen Uyar

Magnesium in chronic kidney disease: challenges and opportunities.

Cardiovascular disease is the leading cause of mortality and morbidity in patients with chronic kidney disease, which is partly explained by the fact that 40–70% of patients receiving dialysis have significant coronary artery disease. Recent clinical studies have shown that lower serum magnesium (Mg) levels are associated with vascular calcification and cardiovascular mortality among patients with end-stage renal disease (ESRD). On the other hand, hypermagnesemia inhibits parathyroid hormone secretion, which is considered an important independent risk factor for vascular calcification, left ventricular hypertrophy and mortality in ESRD patients. Finally, increasing evidence points towards a link between Mg and cardiovascular disease, even in subjects without chronic kidney disease. The purpose of this review was to critically review the current literature examining the effects of plasma Mg levels on cardiovascular disease and parathyroid hormone homeostasis in ESRD, and renal transplant patients.

Causes and Mechanisms of Nondipping Hypertension

Growing evidence indicates that nondippers have worsened cardiovascular outcomes than dippers. Ambulatory blood pressure monitoring with a lack of nocturnal BP fall (nondipping) have also been shown to be more closely associated with target organ damage and worsened cardiovascular outcome than in patients with essential hypertension with dipping pattern. The underlying pathogenetic mechanisms potentially linking nondipping with cardiovascular disease are not fully understood. There are multiple possible underlying pathophysiologic mechanisms in the impaired BP decline during the night. Extrinsic and intrinsic factors including abnormal neurohormonal regulation, lack of physical activity, nutritional factors such as increased dietary sodium intake, and smoking of tobacco have been implicated for blunted circadian rhythm of BP. Certain diseases such as diabetes and chronic renal diseases also affect the circadian BP rhythm. Currently, the clinical importance of nondipping is known well; however, the relationship between certain disease states and nondipping has not been fully explained yet. This paper will attempt to address to clarify the underlying basis for nondipping and the specific associations with various disease states.

Role of Helicobacter pylori in pathogenesis of upper respiratory system diseases.

Helicobacter pylori (H. pylori) is one of the frequently encountered micro-organisms in the aerodigestive tract. Although infections caused by H. pylori are this common, the exact mode of transmission has not been fully understood yet. Oral-oral, fecal-oral and gastrointestinal-oral routes are the possible modes of transmission. This infection is usually acquired in childhood and may persist for the whole life of the patient. However, about 80% of the infected humans are asymptomatic. Human stomach was considered to be the only reservoir of H. pylori until bacteria were discovered in human dental plaque, in oral lesions, in saliva, in tonsil and adenoid tissue. It is suggested that H. pylori enters the nasopharyngeal cavity by gastroesophageal reflux and colonize in the dental plaques, adenoid tissues and tonsils. From these localizations, the bacteria ascend to the middle ear and to the paranasal sinuses directly or by the reflux again and may trigger some diseases, including otitis, sinusitis, phyrangitis, laryngitis and glossitis. But still, the exact mechanism remains unclear.

Relationship between cerebral arterial pulsatility and carotid intima media thickness in diabetic and non-diabetic patients with non-alcoholic fatty liver disease

Non-alcoholic fatty liver disease (NAFLD) is considered a risk factor for atherosclerosis. The aim of the present study was to investigate the association of the pulsatility index (PI) of basilar artery (BA) and carotid intima media thickness (IMT) in diabetic and non-diabetic NAFLD patients. We compared a group of 80 stroke-free, diabetic and non-diabetic NAFLD patients and a control group of 26 healthy subjects without NAFLD. We then evaluated the PI of the BA by transcranial Doppler ultrasonography, and carotid IMT. The PI was significantly higher in diabetic NAFLD patients than in controls (p<0.003). Carotid IMT and asymmetrical dimethylarginine (ADMA) levels were higher in NAFLD patients than controls respectively (p<0.003, p<0.04). The PI of the BA was significantly correlated with age (R=0.369, p<0.001), male gender (R=0.207, p=0.035). diabetes (R=0.332, p=0.001), carotid IMT (R=0.296, p=0.002) and ADMA (R=0.349, p=0.015). A multiple regression analysis was performed with PI as the dependent variable with known clinical risk factors. Age (β=3.54, p<0.001), diabetes (β=2.32, p=0.022), gender (β=2.20, p<0.03), ADMA (β=2.25, p<0.031), and carotid IMT (β=2.41, p<0.017), were independent predictive factors of BA PI. Adjustment for age and gender did not alter these relative risks, exhibiting a significant independent contribution to PI. The increased PI observed in this study represents enhanced cerebrovascular resistance, and we observed that the age, male gender, diabetes, ADMA levels, and carotid IMT were independent predictive factors of BA PI.

Eosinophilic Colitis in a Patient With Advanced Transitional Cell Carcinoma of the Bladder: A Paraneoplastic Syndrome?

Eosinophilia associated with tumors is extremely rare. The exact underlying pathogenetic mechanisms are not well understood; limited data have been reported about granulocyte colony-stimulating factor and interleukin-5 in the development of eosinophilia. We report a patient with marked eosinophilia, leukocytosis, and eosinophilic colitis presenting with bloody stool. The subsequent diagnosis was advanced high-grade transitional cell carcinoma of the bladder. Leukocyte count, eosinophil count, and colonoscopic findings returned to normal after surgical removal of the tumor. To our knowledge, eosinophilic colonic infiltration as a manifestation of transitional cell bladder carcinoma has not been previously reported.