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J Riehl

Publications and source records attributed to J Riehl.

At least 37 records · Page 2Linked to original sources
PubMed1998

Renal oncocytoma of the native kidney after renal transplantation.

Patients with acquired cystic kidney disease (ACKD) are at an increased risk of renal neoplasms. Frequent tumors are adenomas and renal cell carcinomas. However, renal oncocytomas may occur in patients with ACKD. Little is known about oncocytomas of the native kidney following renal transplantation. By means of B scan ultrasonography, a solid and echo-inhomogeneous renal mass was incidentically observed in the right native kidney of a 28-year-old female patient with ACKD 4 years following renal transplantation. A nephrectomy was performed. The histological examination revealed a renal oncocytoma. The increased prevalence of neoplasms in the case of ACKD and following renal transplantation requires careful monitoring of the patients concerned. In very rare cases a renal oncocytoma may develop in the native kidney after renal transplantation.

Adenoma, Oxyphilic↗
PubMed1997

Central administration of vitamin B12 aggravates cataplexy in canine narcolepsy.

Experimental evidence in canine narcolepsy suggests that central cholinergic systems are critically involved in the regulation of cataplexy, an abnormal manifestation of REM sleep atonia. In the current study, we found that intracerebroventricular perfusion of methyl-B12, (10(-5)-10(-2) M), significantly aggravated cataplexy and enhanced REM sleep in narcoleptic dogs. Choline, a direct precursor of acetylcholine, was also found to aggravate cataplexy, while cyano-B12, a vitamin B12 analog without methyl donating abilities, had no effect on cataplexy. Since both methyl-B12 and choline are reported to enhance acetylcholine synthesis, enhancement of the biosynthesis of acetylcholine may be involved in the effects observed in canine narcolepsy. Our results suggest that central administration of methyl-B12 has the potential to modulate both normal and pathological REM sleep.

Analysis of Variance↗
PubMed1997

[Spontaneous portasystemic shunt in liver cirrhosis: imaging with color-coded duplex ultrasonography].

PURPOSE: To demonstrate the usefulness of B-scan ultrasonography and color Doppler ultrasonography (CCDS) in the diagnosis of lumbal and splenorenal collateral veins in patients with liver cirrhosis. METHOD: 46 patients with histologically proven liver cirrhosis were examined by means of B-scan ultrasonography. CCDS was used to demonstrate the vascular character of mass-like lesions or tortuous tubular structures. Esophageal varices were demonstrated in 23 (50%) and ascites in 6 patients (13%). RESULTS: In 5 out of 46 patients (10.9%) we demonstrated lumbal and splenorenal portosystemic venous collaterals by B-scan- and CCDS. In 2 patients localized venous collaterals were demonstrated. No ascites was found in patients with accessory portosystemic shunts. CCDS showed the patency of these spontaneous portosystemic shunts. CONCLUSION: In patients with chronic liver disease CCDS is a noninvasive method to demonstrate spontaneous portosystemic shunts due to portal hypertension. The method provides information concerning patency and flow direction of the collateral veins.

Collateral Circulation↗
PubMed1997

Renal artery stenosis: evaluation with colour duplex ultrasonography.

BACKGROUND: Detection of renal artery stenoses (RAS) by means of duplex Doppler ultrasound with direct scanning of the main renal arteries is subject to numerous limitations. Using semiquantitative analysis of the Doppler curve, which can be recorded from intrarenal arteries, it is possible to detect RAS unaffected by the problems of direct Doppler scanning of the renal arteries. METHODS: Both angiography of the renal arteries and colour duplex ultrasonography (US) of the intrarenal vessels (interlobar arteries) were performed in 214 patients (53.2 +/- 14.1 years) with severe arterial hypertension. Angiography was used as 'gold standard' in the diagnosis of RAS and the Doppler results were compared with the subsequent findings on angiography. At angiography, the reduction of diameter > 70% was assessed as haemodynamically effective RAS. For the duplex Doppler diagnosis of RAS the following parameters were calculated: (a) resistive index (RI) of each kidney, and (b) side-to-side differences of the resistive indices (delta RI) between the right and left kidney. RESULTS: Angiography demonstrated 59 RAS (> 70%) in 53 patients, including six with bilateral RAS. By means of duplex US we found a significant difference of RI between kidneys with RAS (0.48 +/- 0.11) and without RAS (0.63 +/- 0.08; P < 0.001). In addition, a significant difference of the delta RI was noted in patients with RAS (24.4% +/- 12.5%) and the controls without RAS (3.6% +/- 2.7%). Using a combination of both RI and delta RI, threshold values of RI = 0.45 resp. delta RI = 8% yields a sensitivity of 92.5% and a specificity of 95.7% in the detection of haemodynamically effective RAS. CONCLUSIONS: Colour duplex US with calculation of the RI and delta RI of intrarenal arteries is a valuable non-invasive test assessing the haemodynamic effects of a RAS. Low costs and safety support the use of the Doppler technique in screening for renovascular disease.

Adult↗
PubMed1997

The use of duplex sonography in the diagnosis of renal artery stenosis.

Both direct and indirect duplex sonography (DS) permit the diagnosis of significant renal artery stenosis. The validity of direct DS, based on the detection of increases in the blood velocity in stenotic arteries, is affected by numerous factors (inappropriate examination conditions, presence of vascular variants). In the technique of indirect DS, renal artery stenosis is detected via changes in the hemodynamics of intrarenal vessels ('tardus-et-parvus' phenomenon). Various evaluation parameters (signal shape, acceleration time, acceleration index, resistance index, pulsatility index) have proven useful for signal analysis. The intraindividual comparison of the two sides is an important instrument of stenosis detection in indirect DS. In clinically selected populations of hypertensive patients, DS may be used as a method of stenosis screening. DS has proven its practical value as a follow-up method after angioplastic intervention. It remains to be shown in future investigations whether "functional' classification of the degree of stenosis on the basis of Doppler sonographic findings is feasible.

Hemodynamics↗
PubMed1996

[Acute pulmonary syndrome and cavernous pulmonary tuberculosis in a patient with sickle cell disease].

HISTORY AND CLINICAL FINDINGS: A 17-year-old girl from Zaire was admitted to hospital with fever, cough, dyspnoea and severe chest pain. In addition to marked anaemia (haemoglobin 6.6 g/dl) she was known to have cavitary/exudative pulmonary tuberculosis (PTb) with bilateral basal infiltrations. INVESTIGATIONS: Blood gas analysis indicated partial respiratory failure (pO2 55 mm Hg, pCO2 36 mm Hg). Blood smear under air exclusion showed erythrocyte sickling. Haemoglobin electrophoresis demonstrated 92.7% HbS and thus confirmed sickle cell anaemia. A small spleen on sonography and the presence of Howell-Jolly bodies were interpreted as signs of functional asplenia. Microbiological and radiological tests confirmed exudative-cavitary PTb. TREATMENT AND COURSE: The findings were interpreted as due to an acute chest syndrome, caused by sickle cell thrombi in the pulmonary blood vessels, precipitated by the PTb. Transfusion of two units of erythrocyte concentrates led to improvement of the chest pain and the respiratory failure within a few hours. The PTb was successfully treated without any complications. CONCLUSION: Acute chest syndrome is a vascular occlusive complication of sickle cell disease, pulmonary tuberculosis precipitating the development of this acute condition. Administration of erythrocyte concentrate rapidly improves the signs and symptoms.

Adolescent↗
PubMed1995

[Femoral hernia: diagnosis with B-image, duplex and color-coded Doppler ultrasound].

The diagnosis of femoral hernias depends on the recognition of their clinical features. In many cases femoral hernias were incorrectly diagnosed. B-Scan ultrasonography, duplex- and colour-coded Doppler sonography were used to diagnose a femoral hernia in a 60-year old female patient who developed a groin lump after femoral artery puncture. The diagnostic procedure could easily differentiate between haematoma, pseudo-aneurysm, arteriovenous fistula and femoral hernia by the characteristic Doppler spectrum and colour coding. B-Scan ultrasonography, duplex- and colour-coded Doppler sonography can accurately detect femoral hernias and should be routinely used in patients with any kind of groin lump.

Cardiac Catheterization↗
PubMed1995

[Prevalence of goiter in the Aachen area. Ultrasound volumetry of the thyroid gland of 1,336 adults in an endemic goiter region].

AIM: The aim of the study was to assess the prevalence of thyroid enlargement by ultrasonic volume measurements. RESULTS: 1336 adults living in the iodine-deficient area of Aachen, West Germany (760 females, 576 males, mean age: 54.05 +/- 16.09 years) were included in the investigation. The ultrasonic examination was carried out in patients who did not suffer from thyroid disease at the time of study. RESULTS: The thyroid volume was age-dependent and varied from 13.3 +/- 10.4 ml in patients < 21 years to 29.9 +/- 24.3 ml in patients > 70 years. The prevalence of thyroid enlargement ranged from 14.3% in young people to 51.3% in the elderly. There was no difference in the volumes of the left and right thyroid lobe. The prevalence of thyroid enlargement was higher in females compared to males (p < 0.05). Retrosternal thyroid mass was detected in 25% of all patients > 70 years. CONCLUSION: There is evidence of a high prevalence of thyroid enlargement in iodine-deficient areas.

Adult↗
PubMed1995

Medullary nephrocalcinosis: sonographic findings in adult patients.

Medullary nephrocalcinosis occurs in various diseases as a non-specific renal manifestation. We present 5 patients (hypophosphataemic rickets, type 1 renal tubular acidosis, primary hyperparathyroidism, hypercalcaemia of unclear origin, chronic renal insufficiency requiring dialysis) in whom a medullary nephrocalcinosis was demonstrated by means of sonographically detectable changes in the renal medulla region. The sonographic appearance of medullary nephrocalcinosis is characterized by detection of echo-enhanced structures in the region of the renal pyramids. The presence of a medullary nephrocalcinosis can generally be confirmed with adequate reliability on the basis of sonographic findings and characteristic clinical pictures. In individual cases it is difficult to distinguish between medullary nephrocalcinosis and renal calyx calculi.

Acidosis, Renal Tubular↗
PubMed1994

Diagnostic value of indirect pancreatic function test in serum of anuric patients with chronic renal failure.

Although patients with chronic renal failure have a high incidence of chronic pancreatic disease, the condition is frequently overlooked. We have modified the pancreolauryl test--an indirect pancreatic function test--for anuric patients. The test permitted good discrimination between patients with chronic pancreatic disease and those with a normal pancreas when serum levels of fluorescein were measured 10 h after administration with a standard meal. The sensitivity at this time interval was 80% and the specificity 83%. We conclude that the pancreolauryl test with serum measurements provides a simple, noninvasive, and reliable diagnostic test for chronic pancreatic disease in anuric patients with chronic renal failure.

Anuria↗
PubMed1994

Which bicarbonate concentration is adequate to lactate-buffered substitution fluids in maintenance hemofiltration?

We investigated the metabolic and hemodynamic effects of a lactate- and a bicarbonate-buffered (bicarbonate concentration 31.4 mmol/l, type I) hemofiltration substitution fluid in a prospective crossover study of 3 weeks each in 11 patients on maintenance hemofiltration. The lactate-buffered hemofiltration (lactate concentration 34-44.5 mmol/l) lead to hyperlactatemia in all patients without signs of overt lactic acidosis but showed a better control of acid-base balance (pH, base excess, standard bicarbonate) than the type I bicarbonate-buffered fluid (p < 0.01). In 6 patients a higher concentration of bicarbonate- (39.7 mmol/l, type II) buffered fluid was tested. The parameters of acid-base balance showed a better control during type II than during type I bicarbonate hemofiltration and were similar to the lactate-buffered phase. Plasma lactate levels between type I and type II bicarbonate hemofiltration were not different. Also in the steady state phase of the treatment (days 7-9 [week 3]) parameters of acid-base balance rose more to normal values during type II than during lactate-buffered hemofiltration. Hemodynamic parameters showed no differences between the three types of buffers used. Furthermore, also the type II bicarbonate fluid was well tolerated. Bicarbonate in a higher concentration (39.7 mmol/l) proved to be a safe and practical alternative to lactate-buffered hemofiltration.

Acid-Base Equilibrium↗
PubMed1994

Percutaneous renal biopsy: comparison of manual and automated puncture techniques with native and transplanted kidneys.

The diagnostic usefulness of the biopsy cylinder and biopsy-induced complications were investigated for 458 percutaneous renal biopsies (315 native, 143 transplant kidneys) on 339 patients (average age, 44.6 +/- 18.5 years) under two different biopsy regimes (regime I, manual biopsy technique with Tru-Cut needle, 14 gauge; regime Ii, automated biopsy technique using a Biopty instrument and adapted biopsy needle, 18 gauge). In 435 (95%) of the biopsies, kidney tissue with 9.09 +/- 5.28 glomeruli was obtained (regime I, 93.5%, 9.5 +/- 4.9 glomeruli; regime II, 96.5%, 8.7 +/- 5.6 glomeruli; P > 0.05). Neither with native nor with transplant kidneys was there any evident advantage for a particular regime in terms of the diagnostic usefulness of the cylinder. Bleeding complications (perirenal haematomas, bleeding into the renal pelvis, blood clots in the urinary bladder) were observed in 69 (15.1%) patients (regime I, 15.6%; regime II, 14.6%; P > 0.05). Clinically relevant bleeding complications were significantly rarer under regime II (9.1% versus 3.5%; P < 0.05). Complications were less frequent with transplant than with native kidneys (12.6% versus 16.2%). Doppler sonography of the biopsied transplant kidneys revealed arteriovenous fistulae in nine cases (6.3%; regime I, 8.0%; regime II, 5.4%). In general, use of an automated biopsy instrument and a thinner biopsy needle reduced the number of significant complications following percutaneous renal biopsy, while achieving comparably diagnostic efficacy.

Adult↗
PubMed1993

[Arteriovenous fistula and kidney pelvis thrombus after percutaneous kidney puncture].

Percutaneous renal biopsy was performed in a 40-year old transplant recipient suffering from renal function impairment. The examination of the main transplant artery by duplex Doppler ultrasonography showed normal values for the resistive index and renal blood flow volume. Postbioptic realtime ultrasonography showed an echogenic mass in the renal collecting system, which was dilatated in prior examinations. In addition, we found an arteriovenous fistula by colour coded Doppler ultrasonography showing a characteristic Doppler wave-form shape in an interlobar artery. No changes in the resistive index and renal flow volume could be demonstrated by Doppler examination of the main renal artery. The complications of percutaneous biopsy disappeared spontaneously. Although the incidence of major complications after renal graft biopsy with the automated biopsy instrument is very low, our report demonstrates typical complications following percutaneous renal biopsy. We conclude that B-scan and colour coded Doppler ultrasonography are sensitive diagnostic methods to observe patients post biopsy for potential complications.

Adult↗
PubMed1993

Response of vasoactive substances to intermittent ultrafiltration in normotensive hemodialysis patients.

The changes in blood volume (BV), atrial natriuretic peptide (ANP), plasma renin activity (PRA), aldosterone (Aldo), norepinephrine (NE), epinephrine (Epi), parathyroid hormone (PTH), arginine vasopressin (AVP) and the cyclic nucleotides cAMP and cGMP were measured during a fluctuating BV cycle in 15 patients with end-stage renal failure maintained on chronic hemodialysis (HD). HD consisted of 4 periods of about 60 min each. The first half of each HD period consisted of ultrafiltration (UF) greater than 1,000 ml/h, and the second half consisted of no UF. Changes in relative BV were measured using continuous hemoglobinometry. Total BV at the end of treatment was 74.3 +/- 6.9% of the pretreatment volume. A significant positive correlation between BV and the levels of ANP, PTH, Epi and cGMP and an inverse correlation between BV and PRA, Aldo, AVP and NE were demonstrated. While mean values of NE and AVP levels were directly related to actual changes in BV, individual values did not homogeneously reflect this relationship. The cyclic nucleotides cGMP and cAMP did not follow immediate BV changes, but showed a significant decrease correlated with diminished BV. Based on a pre-postdialysis analysis, significant changes in PRA and Aldo were missing. It seems possible that vascular stability in dialysis patients may be maintained by the response of NE and AVP, and not by the renin-aldosterone system. The changes in ANP and cGMP values correlated most significantly (r = 0.38 and r = 0.51, p < 0.005) with the changes in BV, but no single variable could explain the blood pressure regulation during HD with intermittent rapid UF.

Adult↗