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Biomedical subjects

R Kalaitzidis

Publications and source records attributed to R Kalaitzidis.

10 recordsLinked to original sources
PubMed2003

Lipoprotein (a) and acute-phase response in patients with vestibular neuronitis.

BACKGROUND: Vestibular neuronitis (VN) is a relatively common condition characterized by the acute onset of vertigo, nausea and vomiting, in the absence of auditory or central nervous system involvement. The exact aetiology (inflammatory, viral or vascular?) remains obscure. Lipoprotein (a) [Lp(a)] is an atherogenic particle. Its serum levels are mainly genetically determined and vary widely between individuals. Whether Lp(a) is consistently a positive acute-phase reactant is controversial. PURPOSE: We evaluated the alterations in lipidaemic parameters and serum biological markers (including acute-phase reactants) in adult patients presenting acutely with VN. SUBJECTS AND METHODS: A total of 34 consecutive VN patients (24 men and 11 women) and 37 apparently healthy controls (25 men and 12 women) were studied. Laboratory evaluation was performed during the acute episode and 6 months later (stable state). RESULTS: Serum Lp(a) concentrations were significantly lower at the time of presentation (median value 6.4 vs. 16.4 mg dL-1 in the stable state, P < 0.001), whereas fibrinogen levels were significantly higher during the acute episode than in the stable state (median value 293.0 vs. 202.0 mg dL-1, respectively, P < 0.0001). During the acute episode, plasma fibrinogen correlated with CRP levels (Spearman r = 0.84, P < 0.0001). By contrast, inverse correlations were noted between Lp(a) levels and CRP (Spearman r = -0.47, P = 0.007) as well as between Lp(a) and fibrinogen levels (Spearman r = -0.35, P = 0.05). CONCLUSION: Vestibular neuronitis episodes are associated with evidence of an acute inflammatory response as reflected by significant elevations in plasma fibrinogen and CRP concentrations, whereas Lp(a) behaves as a negative acute-phase reactant.

Acute Disease↗
PubMed2001

Metabolic abnormalities in patients with primary open-angle glaucoma.

PURPOSE: Although there are few data on the underlying mechanisms of primary open-angle glaucoma (POAG), it has been suggested that metabolic diseases may play a role in the evolution of the disease. We carried out the present study to investigate the involvement of metabolic disturbances in POAG pathogenesis. MATERIAL/METHODS: Serum metabolic parameters were evaluated in 49 POAG patients without a known history of diabetes mellitus and 72 age and sex matched individuals without glaucoma (control group). RESULTS: Among the metabolic parameters examined, only fasting serum glucose and uric acid levels were found significantly higher in patients with glaucoma compared to the control population (117+/-17 mg/dl vs 105+/-11 mg/dl, p=0.05 and 6.2+/-1.9 mg/dl vs 5+/-1.2 mg/dl, p=0.006, respectively). Additionally, a considerably greater proportion of patients had disturbances of the carbohydrate metabolism and hyperuricemia. CONCLUSION: We conclude that disturbances of carbohydrate and uric acid metabolism could play a role in glaucoma damage and pathogenesis.

Aged↗
PubMed2001

Individual renal function in polycystic kidney disease: a follow-up study.

PURPOSE: This study was undertaken to determine individual renal function in patients with autosomal dominant polycystic kidney disease (ADPKD). MATERIALS AND METHODS: The authors initially examined (study t1) 25 patients with ADPKD (12 female, 13 male; ages 18 to 68 years). The serum creatinine concentration and glomerular filtration rate, measured by Tc-99m DTPA, were 1.5 +/- 0.56 mg/dl and 65.7 +/- 31 ml.minute-1.1.73 m2, respectively. Thirteen patients had a follow-up study (t2) 2 years after their initial evaluations. Individual renal function was assessed on Tc-99m DMSA renal scans. RESULTS: The mean (+/- SD) difference between left kidney DMSA (DMSA-L) and right kidney DMSA (DMSA-R) was 7.04 % +/- 16.48%. In 20 patients (80%), the left kidney had a lower percentage contribution to the total renal function compared with the right kidney. When the results of the two studies were compared, deterioration in renal function was noted. In the t1 study, the mean serum creatinine concentration and glomerular filtration rate were 1.7 mg/dl and 67.02 ml.minute-1.1.73 m2 respectively, and in the t2 study these values were 2.01 mg/dl and 57.15 ml.minute-1.1.73 m2, respectively. No difference, however, was found in individual renal function in the two studies. CONCLUSIONS: In patients with ADPKD, the percentage contribution of each kidney to total renal function is not equal and remains stable during the progression of renal failure.

Adolescent↗
PubMed2000

The effects of the addition of losartan on uric acid metabolism in patients receiving indapamide.

OBJECTIVE: A number of adverse metabolic effects are associated with indapamide administration, including an increase in serum uric acid levels. It has been reported that losartan can significantly decrease serum uric acid levels. However, there are no data on the effects of combination therapy of losartan with indapamide on uric acid metabolism. METHODS: We studied 20 hypertensive patients in whom serum metabolic parameters, including uric acid levels in serum and urine, were studied before and after eight weeks of indapamide administration (2.5 mg once daily) as well as eight weeks after combination treatment with indapamide (2.5 mg once daily)and losartan (50 mg/day). RESULTS: Indapamide evoked a significant decrease in systolic and diastolic blood pressure from a mean value of 157 +/- 12 mmHg/96 +/- 10 mmHg to a mean value of 139 +/- 14 mmHg/92 +/- 5 mmHg (p<0.01 for both comparisons). However, a significant increase in serum uric acid levels was noticed after indapamide administration (from a mean value of 4.9 +/- 1.6 mg/dl to a mean value of 5.9 +/- 1.2 mg/dl, p<0.01), associated with a decrease in the fractional excretion of uric acid(from a mean value of 9 +/- 5% to a mean value of 7 +/- 5.5%, p<0.05). The addition of losartan caused a further decrease in blood pressure from a mean value of 139 +/- 14 mmHg/92 +/- 5 mmHg to a mean value of 120 +/- 15 mmHg/84 +/- 4 mmHg (p<0.01 for both comparisons). This was followed by a significant decrease in serum uric acid levels to 5 +/- 1.1 mg/dl(p<0.01) due to a substantial increase in fractional urate excretion (from 7 +/- 5.5 to 8.7 +/- 6%, p<0.05). CONCLUSION: The addition of losartan could offset the hyperuricaemic effect of indapamide administration.

Adult↗
PubMed1999

Effectiveness and metabolic effects of perindopril and diuretics combination in primary hypertension.

The effectiveness as well as the metabolic effects of the combination of diuretics [hydrochlorothiazide (HCT) vs indapamide (IND)] and perindopril (P) in 14 patients (7 male, 7 female) aged 37-62 years with mild idiopathic hypertension were studied. Following a 4-week wash-out period and a 4-week period of monotherapy with P (4 mg/daily), IND (2.5 mg/daily) or HCT (25 mg/daily) was added for 4 weeks. Selection of the diuretic agent was random. Following a 4-week wash-out period from the diuretic, in which only P was given, the alternative diuretic was administered for another period of 4 weeks. P decreased blood pressure levels significantly. However, the drug was more efficacious in patients with higher plasma renin activity (PRA). Combination treatment induced an additional decrease in the blood pressure levels, mainly in patients with lower PRA. The combination of P + HCT was more effective than the combination P + IND. The addition of either HCT or IND evoked a small but statistically significant increase in serum glucose levels while fasting as well as during the 75 g oral glucose challenge. However, insulin levels did not change significantly during the study. Small but not statistically significant changes in serum electrolytes and lipid parameters were observed during the various phases of the study, while a statistically significant increase in the serum uric acid was noticed when the combination P + HCT was given. We conclude: (1) P in small doses is an effective and safe antihypertensive agent, (2) PRA has a predictive value in determining the effectiveness of P treatment, (3) the combination of P with small doses of HCT or IND is more efficacious than P alone, (4) the combination treatment has adverse effects in the carbohydrate tolerance, while there are not significant changes in serum electrolyte and lipid parameters.

Adult↗
PubMed1998

Multiple electrolyte abnormalities after pamidronate administration.

Pamidronate constitutes a major advance in the treatment of tumor-associated hypercalcemia. However, transient electrolyte abnormalities have been reported after pamidronate administration. We describe here a patient with multiple myeloma and severe hypercalcemia who developed transient but significant electrolyte disturbances (mainly hypophosphatemia and hypomagnesemia) after a single dose of 90 mg of pamidronate, focusing on the underlying pathophysiological mechanisms.

Antineoplastic Agents↗
PubMed1996

Ambulatory blood pressure monitoring in hemodialysis patients.

The aim of our study was the detection of blood pressure (BP) variability during a dialysis session and in the interdialytic period in normotensive and hypertensive hemodialysis (HD) patients using ambulatory blood pressure monitoring (ABPM). Twenty-two HD patients aged 54 (range, 33-78) years who were on HD for a mean of 17.7 (range, 1-70) months were studied. Twelve patients were hypertensives, while the remaining 10 were normotensives (BP < 140/90 mm Hg). In all patients ABPM was performed for a total of 48 h including an HD session. A significant decrease in systolic BP, diastolic BP and mean BP was observed at the end of a dialysis session in hypertensive HD patients. However, in only five patients a reduction of more than 5% In mean arterial BP was noticed. No significant differences were observed in the BP values between the first and the second day after the HD in hypertensive HD patients. Interdialytic BP (both systolic and diastolic) was significantly higher than the postdialysis BP measured either in the clinic or with the ABPM in these patients. Normotensive HD patients exhibited a normal diurnal variation of BP during the first day after the HD session (decrease in BP during the night). On the second day after the HD session an increase in BP (mainly of systolic BP), as well as a loss of diurnal variation were observed. On the contrary, hypertensive HD patients did not exhibit the normal diurnal variation of BP during the first or the second day after the HD session. Hypertensive HD patients exhibited increased daytime and night time BP loads. On the other hand, normotensive HD patients presented with BP loads within normal limits, even though a small increase in these loads was observed on the second day after dialysis. In conclusion, while hypertensive HD patients present a loss of the normal diurnal variation of BP, normotensive HD patients exhibit normal variation during the first day after the HD session. The loss of the diurnal variation during the second day in these patients suggests a volume-dependent state.

Adult↗
PubMedDate not supplied

Unravelling the links between calcium excretion, salt intake, hypertension, kidney stones and bone metabolism.

Evidence from animal, clinical and epidemiological studies suggests that high blood pressure is associated with abnormalities of calcium metabolism, leading to increased calcium loss, secondary activation of the parathyroid gland, increased movement of calcium from bone and increased risk of urinary tract stones. Some of these abnormalities are detectable in children and young people and continue throughout adult life. The cluster of abnormalities may be due either to a primary renal tubular defect ('renal calcium leak' hypothesis) or to the effect of central volume expansion seen in hypertension ('central blood volume' hypothesis). A high salt intake is known to aggravate these abnormalities and their consequences. If substantial calcium loss related to high blood pressure is sustained over many decades, increased excretion of calcium in the urine may result in an increased risk of urinary tract stones, and the increased movement of calcium from bone may result in higher rates of bone mineral loss, thereby increasing the risk of osteoporosis. The present review summarises the evidence, suggests a unifying hypothesis and discusses clinical and public health implications.

Bone and Bones↗