Objective: To investigate the pharmcokinetics and toxicity of high-dose topical colonic 5-aminosalicylic acid (5-ASA, mesalazine) therapy in patients with severely active total ulcerative colitis. Design: During colonoscopy, a tube was placed through the instrumentation channel into the caecum; 4 g 5-ASA (enema) was instil led twice daily through the tube for 3 weeks. Patients: Eight patients with severely active total ulcerative colitis were investigated. Methods: 5-ASA and acetylated 5-ASA were monitored in serum (2 days) and urine (5 days). Colonic transport of Tc99m-labelled 5-ASA enema was measured by the nuclear imaging technique on the fifth day. 5-ASA toxicity was clinically and biochemically monitored. Results: Colonic absorption (Cmax on day 1, 1.4 ± 0.3μg/ml; mean ± SEM) and urinary excretion (total recovery on day 1, 10.5 ± 1.6%) of 5-ASA were low. The half-life of 5-ASA was long (t1/2 4.2 ± 0.9 h) and the percentage of unacetylated urinary 5-ASA (17±2%) was high, suggesting saturation of presystemic 5-ASA acetylation. Dose-corrected absorption, acetylation and excretion rates were two- to threefold lower than reported data from patients in remission. Regional radioactivity of Tc99m-labelled 5-ASA enema was high in the ascending colon (37%) and stool (45%) and low in the transverse (7%), descending (7%) and rectosigmoid (6%) colon. Clinical and biochemical monitoring of these eight patients did not reveal any 5-ASA toxicity. Conclusion: Pharmacokinetics of 5-ASA in patients with severely active total ulcerative colitis show low 5-ASA absorption, acetylation and excretion rates. Colonic transit studies suggest rapid transit of the enema through the left-sided colon. High-dose topical colonic 5-ASA therapy seems to be possible without significant toxicity.
Radionuclide procedures are clinically used for assessing obstruction in dilated urinary tracts. The precise correlation of the isotope retention function with the level of the renal pelvic pressure is not known as yet. It was measured experimentally using 20 minipigs. By means of ureterostomies in situ reaching into the pyelon the 40 kidneys were subjected to varying pressures (seven to 62 cm. H2O) while the renal processing of 123-I-orthoiodine-hippuric-acid was recorded. The correlation of five radionuclide parameters with the pelvic pressure was computed: the time to the peak value of the isotope nephrography (t-max) and renal transit time correlated very well with high grade pelvic pressure (greater than 37 cm. H2O): r = 0.91 and 0.86 respectively, but much less well with low grade pelvic pressure (less than 37 cm. H2O): r = 0.73 and 0.62 respectively. The slope of the third phase of the isotope nephrography (tan-turn) and the time to the turning point of its tangent (t-turn) correlated only weakly with elevated renal pelvic pressure: r = 0.62 and 0.59 respectively. In conclusion, radionuclide procedures give excellent qualitative information on the level of pelvic pressure. They cannot, however, be used even as an indirect means for quantitatively assessing elevated renal pelvic pressure, which in urinary obstruction is thought to be one of the factors jeopardizing renal function.
The typical symmetric lesions in a patient with tumor calcinosis avidly accumulated bone-seeking compounds. Thus, bone scanning is very helpful in the diagnosis of this rare disease, especially if the calcareous masses are not situated periarticularly.
Bekanntlich stellt die Pulmonalisszintigraphie ein wertvolles Verfahren zum Nachweis der intrapulmonalen Blutverteilung dar. Durchblutungsstörungen im Lungenkreislauf manifestieren sich im Szintigramm als Aktivitätsausfälle. Die Perfusionsszintigraphie allein ermöglicht aber keine Aussage über die Ursache der Störung aufzuzeigen. Deshalb folgt dem szintigraphischen Nachweis einer Durchblutungsstörung dessen ätiologische Klärung, wobei diese meist mit einer Thoraxübersichtsaufnahme erfolgt. Unserer Erfahrung nach genügt diese aber nicht immer, eine Obstruktion in der pulmonalen Strombahn von einer reflektorischen Engstellung der Lungenkapillaren durch eine Ventilationsstörung, vor allem bei vorbestehenden kardiopulmonalen Erkrankungen, zu unterscheiden.
A left ventricular apical filling defect was found in a whole-body thallium scan performed for routine follow-up for surgically cured thyroid cancer in a 51-year-old woman. She had no cardiovascular symptoms, and her electrocardiogram at rest and during exercise was unremarkable. Transthoracic and transesophageal echocardiography revealed a double-chambered left ventricle. A prominent fibromuscular ridge distal to the papillary muscles was seen dividing the left ventricular cavity into a small apical portion and a large basal portion. There was no significant intraventricular gradient. No treatment was necessary, and the patient has remained asymptomatic in a 4-year follow-up.
