Biomedical subjects

J Radó

Publications and source records attributed to J Radó.

At least 19 recordsLinked to original sources

PubMed2000

[Hypophosphatemic oncogenic osteomalacia].

The first case of oncogen osteomalacia in Hungary is reported, to draw the attention of the medical profession to it and to present the new data about its pathomechanism. Pathological hip fracture caused by hypophosphataemic osteomalacia due to isolated renal phosphate wasting was found in a previously healthy 19 years old sportsman. In spite of daily 1.5 micrograms calcitriol treatment and phosphate supplementation, hypophosphataemia persisted for 13 years and he needed regular indometacin medication for his bone pain. During that time an 1.5 cm gingival tumour was found and radically removed. The serum phosphate level returned to normal in a few hours after the operation (preoperative 0.51, after 2, 4 and 8 hours 0.61, 0.68 and 0.79 mmol/l respectively), and remained normal without calcitriol. The histological examination showed epulis with fibroblast and vascular cell proliferation, which has never been previously reported in connection with oncogenic osteomalacia. The pain resolved after 3 months and the bone density became normal in one year. Oncogenic osteomalacia must be considered in every case presenting with atypical hypophosphataemic osteomalacia. Careful dental examination is needed also in the course of search for the underlying tumour. Every tumour-like growth, even the common epulis, has to be operated radically and serum phosphate monitored in the postoperative period in all such cases.

Adult↗

PubMed2000

[Transtubular potassium gradient in the diagnosis of potassium metabolism disorders].

The transtubular potassium gradient (TTKG) is a simple physiologically based clinical test to study the renal excretion of potassium. This article reviews the most important physiological changes influencing TTKG, the hypokalaemia and hyperkalaemia, the effect of mineralocorticoids, alkalosis, action of diuretics among other drugs etc. The authors studied the abnormalities of TTKG occurring in clinical conditions (renal patients with nephrotic edema, "dry" patients with renal diseases, liver cirrhosis associated with ascites, and primary hyperaldosteronism) and compare them to the results obtained in healthy people. They consider the test to be useful in the recognition of conditions with hypoaldosteronism (including the various types of pseudohypoaldosteronisms and aldosterone resistance) and hyperaldosteronism as well as renal diseases, in accordance with the data published in the literature. On the basis of their own results, they found the method of determination of TTKG informative and helpful also when investigating the site of actions and the effect mechanisms of the diuretics.

Diagnosis, Differential↗

PubMed1999

[Hyperkalemias].

Hyperkalaemia is a frequent electrolyte disturbance connected with new knowledge and practical routine. It is developed by the disorders of the "external balance" (potassium [K] intake and output) as well as the "internal balance" (distribution of K in the extracellular and intracellular fluid compartments). Factors playing a role in it are: the upright posture, physical activity and hyperosmolality. In the hormonal regulation of K metabolism first of all beta adrenergic agents, insulin and aldosterone have significance; the first two mainly in the internal balance. Hyperkalaemia is occurring especially frequently in renal patients (in acute and chronic renal insufficiency, in dialyzed persons) in patients with diabetes, in adrenal insufficiency (Addison's disease, in selective hypoaldosteronisms and in pseudohypoaldosteronisms) in renal tubular acidosis as well as in response to various drugs (ACE inhibitors, angiotensin receptor antagonists, beta blocking agents, potassium sparing diuretics, NSAID's, anticoagulants etc.). Interactions between illness and drugs as well as between drugs and hormones may have outstanding importance in the development of hyperkalaemia. Physical activity carried out in the upright posture in the presence of hyperosmolality (water restriction together with salt or/and glucose loading) developing in pharmacological hypoaldosteronism accompanied with insulin deficiency, may be especially dangerous with respect to hyperkalaemia. To avoid life-threatening hyperkalaemia it is necessary 1. to stop cardiotoxicity with calcium; 2. to enhance K uptake by the cells by bicarbonate, insulin and beta adrenergic agents; and 3. to remove abnormal quantities of K from the body by enemas and/or ion exchange resins. The quickest and best way of treatment of hyperkalaemia is haemodialysis.

Acidosis, Renal Tubular↗

PubMed1998

[Nephrogenic diabetes insipidus].

The syndrome of polyuria and polydipsia is practically identical in three very different disorders (central diabetes insipidus, nephrogenic diabetes insipidus, primary polydipsia). In congenital nephrogenic diabetes insipidus both the thirst mechanism and the production of the antidiuretic hormone are intact, but the hormone is ineffective in the kidney. The acquired form of the disease is caused most frequently by tubulointerstitial and urinary tract obstructive disorders as well as among the several drugs, lithium. In the differential-diagnosis the results of determinations related to the nomograms of normal interrelationships between osmolality and vasopressin in urine and plasma are used, besides the classical Carter-Robbins and indirect dehydration (Miller) tests. It has been postulated recently that in many cases the resistancy toward vasopressin is not absolute and these partially vasopressin sensitive patients can be treated successfully by thiazide, and potassium sparing compounds, antiprostaglandin pain killers (non-steroid antiinflammatory drugs) and first of all dDAVP as well as combinations of these preparations.

Diabetes Insipidus, Nephrogenic↗

PubMed1997

[Hyponatremia].

Hyponatremia is the most frequent electrolyte disorder. Two forms of it, the "true"--and "pseudo"--hyponatremia are known. The normal osmoregulation is an accurate operation which ensures the steadiness of serum sodium level by regulating vasopressin (ADH) release and water intake. Hyponatremia usually indicates water excess in the body, however, it may be complicated by sodium loss as well. It has hypovolemic, hypervolemic and normovolemic forms; the syndrome of inappropriate antidiuretic hormone (SIADH) is associated mostly with the normovolemic states. Nowadays the pathomechanism, criteria, diagnosis and etiologic factors of SIADH (water intoxication) are fairly well known, but the number of drugs capable of inducing this syndrome is increasing day by day. According to the newest knowledge, SIADH may exist not only in the acute but chronic form as well, which should be born in mind when treating water intoxicated patients. The basic principle is that in cases with mild clinical disturbances aggressive treatment should be avoided. For mild hyponatremia water restriction is usually sufficient, but in serious cases hypertonic saline infusion should be administered. Its speed has to be determined and adjusted carefully according to the needs of the patient, and it can be combined with the administration of furosemide, when necessary. Vasopressin antagonists are under clinical investigation, their therapeutic value has not yet been determined. Water intoxication is not rare-if one keeps it in mind. The syndrome's simple treatment can be life saving for the patient and provides an easy problem solution for the physician.

Acute Disease↗

PubMed1997

[Role of aldosterone in potassium secretion in chronic renal failure associated with hypertension (transtubular potassium gradient)].

Aldosterone protects against hyperkalemia in disorders with reduced number of over-working nephrons. It is not clear however, whether diminished aldosterone production or aldosterone resistance is responsible for the hyperkalemia in chronic renal failure. The importance of this question is underlined by the fact that antihypertensive drugs often reduce aldosterone level. Therefore we investigated the distal tubular potassium "driving force" (transtubular potassium gradient) in 9 patients with chronic renal failure accompanied by hypertension and compared it to the results obtained in 10 healthy persons. Glomerular filtration rate was 15.77 +/- 4.88 ml/min in the chronic renal patients. Serum potassium was normal in 3 of 9 patients, the average 4.88 +/- 0.16 mmol/l, higher than in healthy persons 4.27 +/- 0.09 mmol/l (p < 0.001). Nevertheless the transtubular potassium gradient was lower in patients (3.52 +/- 0.32) comparing to healthy persons (7.25 +/- 0.57, p < 0.001). The patients' plasma aldosterone was much higher than normal. The reduced tubular potassium secretion-decreased "driving force" --suggested to aldosterone resistance. We conclude that the renal tubules' aldosterone resistance is not an exceptional but rather frequent feature in chronic renal failure which should be considered when administering antihypertensive drugs.

Aldosterone↗

PubMed1997

[ACE inhibitor therapy of hemodialyzed patients].

Authors studied the daily dose of angiotensin converting enzyme inhibitor captopril and enalapril in patients with hypertension on regular hemodialysis of three hemodialysis units, and the relationship between the daily doses of angiotensin converting enzyme inhibitors and the number of simultaneously used other antihypertensive agents in the same patients. 104 out of 133 hemodialysed patients were treated with antihypertensive agents, 53 patients received angiotensin converting enzyme inhibitor. The data of 23 captopril treated patients in 3 dialysis units and data of 17 enalapril treated patients in 2 dialysis units were used as the basis of the study. The difference between the average daily doses of captopril applied at the different hemodialysis units was significant (111, 61 and 26 mg/day). However the difference between the average doses of enalapril was not significant (18 and 12.9 mg/day). The correlation was found to be significant between the dose of captopril and the number of simultaneously used antihypertensive agents: r = 0.46, p < 0.05. The correlation was also significant between the dose of enalapril and the number of combinations of other antihypertensive agents: r = 0.50, p < 0.05. These relations and the analysis of antihypertensive therapy of 4 patients, receiving the largest doses of captopril suggest that larger doses of angiotensin converting enzyme inhibitors were used in the more resistant hypertensive patients, where more antihypertensive agents were needed to be administered to control the blood pressure.

Angiotensin-Converting Enzyme Inhibitors↗

PubMed1997

[Adult-onset sex-linked familial hypophosphatemic osteomalacia].

Three patients (a grandmother, her daughter and her grandson) belonging to a 23-number-kindred of five generations suffered from adult-onset, X-linked, familiar hypophosphataemic osteomalacia. According to the familiar anecdotes the great-grandmother also had the same disease. The clinical diagnosis was documented by X-ray pictures, scintigraphic and bone histological results, the laboratory diagnosis was proven by blood and urine analyses examined after phosphate loading. The youngest, 24-year-old patient was treated with daily 3 g phosphate and high doses of calcitriol for 2 years. As a new feature of our therapy, per os treatment with 1.25 micrograms calcitriol was supplemented by daily 2-4 micrograms iv. bolus calcitriol for one week every month. The osteomalacia, causing serious symptoms and complaints, healed. Our treatment seemed to be safe, as renal functions, serum total and ionized calcium and PTH levels (including midnight values) remained in normal range. On the basis of our results this disease can be treated by administration of high doses of phosphate, provided that development of hyperparathyroidism is prevented by the coadministration of high doses of calcitriol.

Adolescent↗

PubMed1996

[Potassium-sparing diuretics (spironolactone, triamterene, amylorid)].

The group of drugs, so-called "potassium sparing diuretics" represent an important part of our modern therapeutic arsenal. Their "weak diuretic" properties are especially beneficial in cirrhotic patients with ascites, when highly effective loop diuretics may be hazardous. Potassium sparing diuretics have not only the advantage of avoiding potassium loss, but can potentiate the effects of diuretics acting in distal tubules and Henle's loop also. They may be combined by each other or ACE inhibitors too, taking the necessary precautions and laboratory monitoring. Their indications include the hypertension and special diseases as Conn's, Bartter's, Liddle syndromes and hirsutism. The broad clinical usefulness justifies the drug inventory ambition to develop new, more effective potassium sparing compounds without side effects. Authors overview their main clinicofarmacological properties, therapeutical indications alone or in combinations and their potential side effects.

Amiloride↗

PubMed1996

[Water intoxication in pulmonary tuberculosis complicated by aspergillosis].

The authors found a serum sodium level of 113 mmol/l in a 70 year old confused male patient with cachexia and fever, which level rised to 125 mmol/l as a result of hypertonic sodium chloride and furosemide therapy, resulting in improving sensorium. At the same time the urine osmolality (235 mOsm/kg) was high compared to the serum osmolality (258 mOsm/kg). The physical and radiological examination showed bilateral pneumonia. The patient died in acute circulatory insufficiency. At the autopsy miliary pulmonary tuberculosis with superinfection by aspergillosis was proved. The authors discuss the possible mechanisms of water intoxication occurring with lung diseases and the difficulties regarding the diagnosis and therapy of aspergillosis.

Aged↗

PubMed1995

[The effect of captopril on the acidification function of the kidney in hypertension].

The effect of the converting enzyme inhibition treatment on the renal acidification function was studied in 5 mild hypertensive subjects. Before and after one week treatment with daily 75 mg of captopril bicarbonate loading was carried out by peroral administration of 68 mmol NaHCO3. The difference between the partial carbon dioxide tension (pCO2) of the urine and blood [(U-B) pCO2], as well as the pH and bicarbonate values were determined at every hour in the course of 3 hours. In the same persons phosphate loadings were also carried out. Although decrease H+ excretion may follow the suppression of aldosterone, which could be expected in response to the short-term captopril treatment, no such change in distal tubular function could be demonstrated by the sensitive methods administered in this study. It seems to be highly probable, that captopril does not limit the urinary acidifying function in patients with healthy kidneys.

Administration, Oral↗

PubMed1995

[Simultaneous familial occurrence of distal renal tubular acidosis, polycystic kidney and nephrogenic diabetes insipidus].

In five members of three generations in a family studied in 1972, 3 nephrological disorders occurred concurrently: distal renal tubular acidosis (dRTA), polycystic kidney and nephrogenic diabetes insipidus (with the exception of a five-year-old child in whom polycystic kidney was not detectable--yet?). Chromosoma studies revealed an increased rate of the occurrence of variations. The youngest patient was reinvestigated in 1993; the other four affected members of the family were already not alive. 7 offsprings in two generations of the 3 healthy members of the third "patient generation" were healthy. The autosomal dominant way of inheritance characteristic to both dRTA and polycystic kidney disease was obvious in this family. On the other hand the same degree of the concentrating defect found both in the patients of the familial dRTA and in 11 control patients with non familial (acquired) dRTA suggested that the nephrogenic diabetes insipidus as an acquired disorder was associated with the two congenital abnormalities. The clinical picture of the combined disease was dominated by the symptoms of polydipsia and polyuria. The vasopressin resistance with a variation in the degree interindividually seemed to be responsible for the nephrogenic diabetes insipidus. Functional insufficiency of the loop of Henle was excluded on the basis of normal responses to a "loop diuretic".

Acidosis, Renal Tubular↗

PubMed1995

[Repeated serious water intoxication in an aged patient. (Data on the relationship between the inappropriate antidiuretic hormone syndrome and the atrial natriuretic factor)].

An old women was in an 8-year-period 9 times admitted to the hospital because of severe mental disturbances. The average serum sodium concentration was 126.25 +/- 2.43 mmol/l at the admissions; it increased to 139.44 +/- 1.40 mmol/l after intravenous infusion of hypertonic solutions accompanied with the disappearance of the mental disturbances. The patient was usually chronically hyponatremic due to the increased water intake and the insufficient water excretion. The latter was induced by the augmented vasopressin levels. The remarkable feature of the syndrome of inappropriate antidiuretic hormone secretion was its association with lowered blood level of atrial natriuretic factor accompanied by sodium, and volume depletion. Discontinuation of the exaggerated water intake resulted in the elimination of the permanent hyponatremia; no episode of water intoxication occurred during the last 3 and 1/2 years.

Aged↗

PubMed1994

[Clinical spectrum of distal renal tubular acidosis and its study with bicarbonate loading].

Authors attempted to review the clinical spectrum of distal renal tubular acidosis on the basis of analysing the records of 11 patients. Distal renal tubular acidosis was associated with chronic renal failure of different severity and with tubulointerstitial diseases in the two-third of patients in whom histologic studies were also performed. The disorders caused in certain cases hypokalemia and hyperkalemia in the others, the concentrating insufficiency was characteristic leading in exceptional cases to nephrogenic diabetes insipidus and the clinical picture was accompanied also by osteomalacia. Authors describe their own method of bicarbonate loading, obtaining by its use very high values of 78.65 +/- 11.28 (p < 0.005) mmHg of urine minus blood pCO2 in 6 healthy subjects. On the other hand, in 6 distal renal tubular acidosis patients no such difference in the pCO2 values could be found. The knowledge of the clinical spectrum of the distal renal tubular acidosis may enhance the recognition and treatment of the disorder.

Acidosis, Renal Tubular↗

PubMed1994

[Effect of calcitriol, a vitamin D compound, in bone disease associated with distal renal tubular acidosis].

In a 47-year-old female patient distal renal tubular acidosis (dRTA) led to the development of osteomalacia following 13 years of the first episode of hypokalemic respiratory paralysis and 7 years of KHCO3 treatment. In spite of the musculoskeletal disability, intense bone pain and myopathy, the values of serum calcium (Ca++) and phosphorous (P) showed minimal deviation from the normal levels. The bone scintigraphy was the first indicator of the bone disease. As the disease progressed the serum level of alkaline phosphatase increased gradually and 25-hydroxyvitamin-D level decreased and bone scintigraphy showed multiple areas of increased radioisotope uptake. By that time the patient's condition deteriorated severely, she became almost unable to walk. Rocaltrol (calcitriol) therapy led to dramatic clinical improvement and the complete resolution of the laboratory values. When the alkaline therapy of dRTA does not prevent the development of osteomalacia, administration of a modern vitamin-D preparation can result complete healing of the bone disease.

Acidosis, Renal Tubular↗

PubMed1994

[Atrial natriuretic factor: a "physiological diuretic"].

Investigators are studying for hardly more than 10 years the special role of the atrial natriuretic peptide, "the physiological diuretic", in maintaining of the volume homeostasis. The ANF is synthesized in the atrial granules and also in extra-atrial organs; there are more members of this peptide family: the brain natriuretic peptide, the C-type natriuretic peptide and the urodilatin. The release of ANF is stimulated mainly by atrial wall distension, but some other mechanism may regulate its secretion too. It has regulatory properties on the cardiovascular, renal and endocrine systems. The most important vascular and renal effects of the hormone are as follows: vasodilatation, decrease in blood pressure, increase in glomerular filtration rate, renal blood flow, and filtration fraction, inhibition of sodium and water reabsorption in the proximal and distal renal tubules (natriuresis and diuresis), and decrease in concentrating ability. ANF is the counterregulatory hormone of the renin-angiotensin-aldosterone system. Its other endocrine interactions are complex, mutual stimulation and inhibition between ANF and vasopressin takes place either. The serum level is often elevated in edematous disorders, but there may be tubular resistance to the hormone's action. The therapeutical importance of this "physiologic diuretic" in volume retaining disorders has been proposed, but it needs further studies to establish the clinical therapeutical value of the hormone.

Atrial Natriuretic Factor↗

PubMed1993

[The value of transesophageal echocardiography in the detection of left coronary proximal stenosis].

Transesophageal echocardiography was performed in 34 patients before coronary angiography for suspected coronary artery disease to determine the usefulness in the detection of proximal left coronary stenosis. The control group consisted of 18 patients in whom coronaroangiography seemed to be negative. The diameter of the visualized coronary arteries, the systolic and diastolic peak flow velocities were measured. The left main coronary artery was visualized in 32 patients, the left anterior descending artery in 31 and the proximal part of the circumflexus artery in 23 patients of the coronary artery disease group, and in the same rate in the control group. The visualization of the right coronary artery was available only in 20-25% because of technical difficulties. The diastolic peak flow velocity over 60 cm/s in the left anterior descending artery reflected proximal stenosis with high sensitivity. In four patients transesophageal echocardiography was performed before angioplasty and after successful intervention. The high diastolic peak flow velocity significantly decreased in every patient. According to the observations the method can be used to perform morphologic and functional measurements on the left proximal coronary arteries.

Adult↗

PubMed1993

[Dobutamine stress echocardiography: a new possibility in the diagnosis of coronary disease].

Authors performed dobutamin stress test since 1987 and combined their examinations with 2D-echocardiography in case of suspected coronary artery disease since October 1991. In this study they report on their experiences obtained in the course of the first 32 examinations. The results of the dobutamine stress echocardiography were analysed on the basis of coronarography which was performed in every patient. According to their observations dobutamine stress echocardiography has very good sensitivity and specificity and it is practically a harmless method, but as it requires instruments, assistants, time and work. Authors recommend the method first of all as a complementary to the physical loading method as well as alternative loading examination.

Coronary Disease↗