[Diagnostic endoscopy and endoscopic ultrasonography of gastrointestinal stroma tumors]. / Endoskopische und endosonographische Diagnostik gastrointestinaler Stromatumoren.

Endoscopy and endoscopic ultrasonography (EUS) are important diagnostic tools for the diagnosis of gastrointestinal stromal tumors (GIST), especially for small incidental GISTs of the stomach and are necessary to make a decision for further procedures. In this overview the technical aspects and the use of endoscopy and EUS in the diagnosis of GIST, including endoscopic probe sampling and resection as well as the current limitations are described. The incidence of GIST and the differential diagnosis by endosonography are also described. This article concentrates on the data based description of the current diagnostic and therapeutic recommendations in suspected small GISTs with respect to the European Society of Medical Oncology (ESMO) guidelines. Finally, the limited options of endoscopic treatment of GIST complications (bleeding, stenosis) and the significance of endoscopy and EUS in further diagnosis of GIST which had been suspected from radiological imaging are briefly discussed.

Resection of a branchiomeric paraganglioma at a rare extrapulmonary location.

Thoracic paragangliomas are a rare cause of hypertension. We report the occurrence of a sporadic benign norepinephrine-producing branchiomeric paraganglioma in a 32-year-old man with paroxysms of hypertension. After localization by iodine 123-metaiodobenzyl-guanidine scintigraphy and magnetic resonance imaging, the paraganglioma was resected successfully below the right pulmonary artery through a right-sided posterolateral thoracotomy. The particular location was consistent with a branchiomeric paraganglioma in an extremely rare extrapulmonary location.

Urinary fibronectin excretion in streptozotocin-diabetic rats.

Previous investigations performed in human diabetics demonstrate an increase in their urinary fibronectin excretion which was already present in subjects without microalbuminuria and which was elevated prior to functional restrictions. The present study was performed to examine whether in an experimental model these data obtained in men can be confirmed using an animal experimental model, and to further study pathomechanisms of diabetic nephropathy in rats. Fibronectin levels in serum and urine, and renal functional properties such as creatinine clearance, urinary albumin and protein excretion were studied in rats rendered diabetic with streptozotocin and compared with values of control and insulin treated animals for 5 months. Diabetic animals demonstrated the same creatinine clearance, but slightly decreased albumin and total protein excretion rates compared to controls and insulin "treated", euglycaemic animals. Diabetic rats showed a significantly increased excretion following day 42 compared to controls and insulin "treated" group. Concerning serum fibronectin, there was no significant difference between control, diabetic and insulin "treated" animals. The urinary fragment pattern of fibronectin was analyzed qualitatively by immunoblotting pattern and consisted of two main bands (M(r) 66,000 and 45,000). These bands were not altered in controls, insulin "treated" and diabetic rats, independent of the stage of renal involvement in diabetes. Present data provide evidence that fibronectin excretion is elevated in diabetic animals prior to functional restrictions, confirming results obtained in human diabetics. Therefore, determination of urinary fibronectin can serve as a more sensitive indicator for renal involvement in diabetes mellitus than microalbuminuria or changes in glomerular filtration rate. Urinary excretion may therefore serve as an early marker for the renal involvement in diabetes before the onset of clinical symptoms.

Extracellular matrix proteins as early markers in diabetic nephropathy.

Basement membrane thickening and mesangial expansion characterize the renal involvement in diabetes mellitus and precede any symptoms of renal dysfunction, e.g., albuminuria and changes in glomerular filtration rate. Since the morphological changes can only be diagnosed by biopsy, this study was designed to investigate whether the urinary excretion of renal extracellular matrix proteins might reflect the morphological alterations. To specify the extent of renal involvement in diabetes, the patients, type I as well as type II diabetics, were classified according to their urinary albumin excretion: normal albumin excretion below 30 micrograms/min, microalbuminuria from 30 to 300 micrograms/min, and overt albuminuria above 200 micrograms/min. Laminin, collagen IV, and fibronectin, all intrinsic components of the renal extracellular matrix, were determined in serum and urine by radioimmunoassay or enzyme-linked-immunosorbent-assay, respectively. The results are given as median values (mean). Additionally, the urinary fragment pattern of fibronectin was analysed qualitatively by immunoblotting. Laminin concentrations in serum and in urine did not change in diabetics. Collagen IV decreased in serum of patients with increased albumin excretion (controls: mean = 255 micrograms/l, normoalbuminuric patients: mean = 56 micrograms/l, microalbuminuric patients: mean = 52 micrograms/l, and patients with overt albuminuria: mean = 70 micrograms/l; alpha < 0.01) and increased in urine (controls, normoalbuminuric and microalbuminuric patients: not detectable, patients with overt albuminuria: mean = 5 ng/12 h; apha < 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)