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H Riedmiller

Publications and source records attributed to H Riedmiller.

At least 55 records · Page 3Linked to original sources
PubMed1995

Primary osteosarcoma of the kidney. Case report and review of literature.

Primary osteosarcoma of the kidney is an extremely rare phenomenon with less than 20 previously reported cases in the English literature since 1936. Diagnosis usually is made in advanced stages of disease with weight loss, palpable tumor, flank pain and gross hematuria being the characteristic features of clinical presentation. Radiographically bizarre renal calcifications may be suggestive of this uncommon neoplasm. The atypic location is explained by metaplastic changes of originally primitive embryonic mesenchymal tissue. Though the primary treatment for sarcomas is surgical resection, because of their usual late and high stage presentation multimodal adjuvant therapy may be desirable. We describe the clinical course of a 48-year-old male patient with a primary renal osteosarcoma discovered by ultrasound. A marked reduction of vital tumor cells and an impressive increase of neoplastic bone formation following polychemotherapy is demonstrated histopathologically. The principal clinical findings, differential diagnosis, etiology, pathogenesis and treatment modalities of this uncommon malignancy are discussed.

Combined Modality Therapy↗
PubMed1995

Quantification of crystal growth of calcium oxalate in gel and its modification by urinary constituents in a new flow model of crystallization.

PURPOSE: To use a new flow model of crystallization to quantify the growth of calcium oxalate monohydrate (COM) in a gel matrix under simulated physiological conditions. MATERIALS AND METHODS: Artificial urine supersaturated in COM was conducted through channels containing a gel with COM seed crystals (flow rate: 0.5 ml. per minute; reaction time: 4 hours; 37 +/- 1C). A relative crystal growth parameter, Vcr, was quantified by discontinuous measurement of scattered light intensity by microphotometry. The effects on Vcr of varying a series of urinary parameters were investigated within the system. RESULTS: The following order of effectiveness in changing COM growth could be derived: dilution > oxalate > calcium > magnesium approximately citrate. CONCLUSIONS: Drinking therapy and lowering of urinary oxalate excretion can be concluded to be the most promising means of preventing CaOx urolithiasis. The new crystallization model demonstrated here should be suitable to new applications in the investigation of urinary stone formation.

Calcium Oxalate↗
PubMed1995

In vitro formation of "urinary stones": generation of spherulites of calcium phosphate in gel and overgrowth with calcium oxalate using a new flow model of crystallization.

Calcium phosphate (CaP) has been detected in the majority of urinary stones containing predominantly calcium oxalate (CaOx). Therefore, crystal phases of CaP might play an important role with respect to the formation of urinary calcium stones in general. Very often, CaP found in stones or tissue of human kidney occurs in the shape of small spherulites. In this paper, we report on a new flow model of crystallization (FMCG), which has been used to generate spherulites of CaP in a gel matrix of 1% agar-agar at 37 degrees C from a supersaturated, metastable solution continuously flowing over the gel surface. Scanning electron microscopy (SEM), X-ray diffraction and microscopic Fourier transformed infrared spectroscopy (FTIR) revealed that the particles formed (diameter: up to 200 microns) consisted of a poorly crystalline core of carbonatoapatite which was partly surrounded by a well-crystallized shell of octacalcium phosphate (OCP) showing radially oriented sheet-like structures. Subsequently, CaOx was grown on these spherulites from a flow of a correspondingly supersaturated solution conducted over the gel matrix. It could be shown by SEM that growth of calcium oxalate monohydrate (COM) was characteristically induced by the OCP shell. Radial sheet-like forms of OCP were directly continued by COM showing a certain radial orientation. The model of crystallization in gel matrices applied here should be well-suited to simulate the process of urinary stone formation under in vitro conditions.

Calcium Oxalate↗
PubMed1994

Tumor-forming eosinophilic cystitis in children. Case report and review of literature.

Eosinophilic cystitis is an unusual bladder lesion of unclear etiology first described in 1960. It usually causes irritative voiding symptoms and hematuria and in its rare tumor-like appearance the disease may mimic an invasive bladder neoplasm. In the report herein, a case of an 11-year-old boy with a tumor-forming eosinophilic cystitis is presented which was mistaken for an infiltrative vesical malignancy until the histopathological study was completed. The principal clinical findings, differential diagnosis, etiology, pathogenesis and treatment modalities of this inflammatory disease are discussed.

Child↗
PubMed1994

[Focal necrotising vasculitis of the testis. Testicular manifestations of immunologic diseases in differential diagnosis of testicular cancer].

We report on the case of a 31-year-old male patient with focal testicular vasculitis as the only clinical manifestation of endangiitis obliterans (Winiwarter-Buerger disease), who presented with acute scrotal pain and swelling suggestive of a testicular tumor. Doppler sonography revealed significantly increased vascularization at the borders of the lesion, which rather indicated a vascular process; however, the presence of solid areas meant that the possibility of testicular cancer could not be excluded. Left inguinal orchiectomy was performed. The surgical specimen revealed histological patterns compatible with endangiitis obliterans; Raynaud phenomenon was the only sign of systemic disease, and no other organs were found to be affected. Despite the high sensitivity and specificity of ultrasound/Doppler sonography, in the differential diagnosis of an unexplained testicular mass surgical exploration is still mandatory. The different types of focal vasculitis are described and discussed with reference to the literature.

Adult↗
PubMed1993

Reservoir characteristics of Mainz pouch studied in animal model. Osmolality of filling solution and effect of oxybutynin.

In a canine model of the Mainz pouch, intracavitary pressure and compliance were measured during instillation of isosmotic and hyperosmotic (900 mmol/kg water) solutions of saline. Wall properties of small- and large-bowel segments of the pouch were assessed individually by sonomicrometry. Intraluminal pressures increased more steeply during filling with hyperosmotic solution, resulting in reduced distensibility of small- and large-bowel segments. Additionally, instillation of the hyperosmotic solution resulted in increased amplitudes and frequency of intracavitary pressure waves. The results indicate that this was the result of a combination of intensified bowel contractions and an increased mural tension. Topical application of oxybutynin abolished these effects. These findings are reviewed in light of the nocturnal increase in urine osmolality, its correlation with nocturnal incontinence in patients with enterocystoplasty, and possible treatment choices.

Animals↗
PubMed1992

The buccal mucosal graft for urethral reconstruction: a preliminary report.

Autologous buccal mucosa as a substitute for urethral epithelium was studied in 2 dogs and used in 6 patients with difficult urethral reconstruction problems. The indications for an operation in these patients were failed hypospadias repairs with limited skin in 3, severe structure disease after hypospadias repair in 1, a short urethra in 1 and epispadias in 1. Three urethral fistulas and 1 meatal stenosis occurred in 3 patients. No urethral stricture or diverticulum was noted, and the final outcome was good functionally and cosmetically in all patients. This technique is useful for urethral reconstruction when local skin is not available.

Adolescent↗
PubMed1992

Paraurethral actinomycosis.

Actinomycosis of the genitourinary tract is rare. Herein we report a case of actinomycosis of the urethra following staged hypospadia repair. Pathophysiology and treatment options of this rare lesion are discussed.

Actinomycosis↗
PubMed1992

Appendix as continent urinary reservoir outlet.

The submucosally embedded in situ appendix offers an ideal continence mechanism in patients with ileocaecal urinary reservoir. Ninety-two patients who underwent this procedure at three urology centres (48 patients in Mainz, 20 in Wuppertal-Barmen and 24 in Marburg) are reviewed. The appendicocutaneous stoma was placed in the lower right abdominal quadrant in 12 patients (most of whom previously had bladder exstrophy) and into an umbilical or, in some exstrophy cases, a neoumbilical tunnel in 80 patients. Urodynamic investigations of the submucosally embedded appendix showed maximum closure pressure greater than 80 cm H2O.

Appendix↗
PubMed1991

[Organ-preserving surgery of renal cell carcinoma. The surgical technic, results and complications].

Operative method, course and complications were analysed retrospectively in 120 patients in whom a kidney tumour had been resected without nephrectomy. In 49 patients (18 women and 31 men, mean age 59 [38-77] years; 45 renal-cell carcinomas, 4 benign renal tumours) there was an "imperative indication" for an organ-preserving operation, because nephrectomy would have made dialysis obligatory. In 74 patients with a healthy contralateral kidney (25 women, 49 men, mean age 55 [31-74] years; 61 renal-cell carcinomas, 13 benign tumours) the tumour was enucleated by choice; 55 of these patients were symptom-free. 36 of 49 patients with an imperative indication are without sign of tumour progression after a mean follow-up period of 4.5 years. In two there was a recurrence after 4 and 5 years, respectively, requiring a second organ-preserving operation. Known metastases were present in 3 of 6 patients who died of their tumours. 68 of 74 patients operated on electively are without signs of tumour progression after a mean follow-up period of 3.3 years. One patient died from tumour metastases. Two patients had tumour recurrence, requiring nephrectomy and enucleation, respectively.

Adult↗
PubMed1991

Medullary sponge kidneys and unilateral Wilms tumour in a child with Beckwith-Wiedemann syndrome.

The occurrence of a Wilms tumour in a 4-year-old girl with bilateral medullary sponge kidney. Beckwith-Wiedemann syndrome and congenital hemihypertrophy demonstrates the close relationship between these disorders. Another six cases from the literature with congenital hemihypertrophy and with medullary sponge kidney are discussed, two of them also developed intraabdominal neoplasm.

Beckwith-Wiedemann Syndrome↗
PubMed1991

Renal abscess in childhood: diagnostic and therapeutic progress.

During the past decade new techniques such as computed tomography (CT) and ultrasonography have been reported to have changed the diagnostic investigation and treatment of renal abscess in adults. To evaluate whether similar changes have taken place in the pediatric age group, a retrospective study of all patients seen between 1979 and 1989 was performed. Seven patients, 0.8 to 14 (mean, 9) years old, with renal abscesses in eight kidneys were identified. Ultrasound and computed tomography proved to be the most valuable diagnostic tools, revealing the diagnosis by showing a hypoechoic or hypodense mass. All patients had an initial trial of intensive antibiotic treatment, which led to resolution of the abscesses in two of the eight kidneys. In all other cases the abscesses were additionally drained, which was done surgically in two and by ultrasonography- or CT-guided percutaneous drainage in four patients. Abscess cultures grew Staphylococcus aureus (three), Escherichia coli (one) and Salmonella Group B (one) and were sterile in one case. Drainage was unsuccessful in only one patient, who subsequently underwent nephrectomy for uncontrolled infection of a diffusely damaged kidney. We conclude that the diagnosis of renal abscesses is greatly facilitated by ultrasonography and CT and that most patients can be cured without operation by antibiotics and, if necessary, by additional percutaneous drainage.

Abscess↗
PubMed1991

Long-term follow-up of children with surgically treated vesicorenal reflux: renal growth.

Renal growth after successful surgical correction of vesicoureterorenal reflux (VUR) in childhood was observed in 137 female and 22 male patients over a mean follow-up period of 10.5 years. The renal parenchymal area was determined using a compensatory planimeter. For each measured value, the standard deviation score (SDS) was calculated by comparison with a normal population. On average, renal growth after reflux operation nearly paralleled the expected normal growth rate. Scarred kidneys had a worse growth prognosis than refluxing renal units (RU) without renal damage, growth retardation being correlated with the degree of pyelonephritic changes. The diminished growth rate of scarred kidneys was accompanied by a compensatory growth of the contralateral kidney. In the absence of renal scars, a modest tendency toward growth retardation was seen in kidneys with previously high degrees of VUR. In 39.7% of the unscarred RU with an initial SDS less than -0.5, accelerated growth (change in SDS of 0.5 or more) was observed. Accelerated growth was most accentuated on small unscarred kidneys (initial SDS less than -2.0).

Adolescent↗