[Gadolinium for DSA in two patients with azotemia: Images of suitable quality and risk of acute renal failure]. / Angiografia con Gadolinio in due pazienti azotemici: la qualita' diagnostica ed il rischio d'insufficienza renale acuta.

BACKGROUND: Gadolinium is an alternative angiographic contrast agent in patients with impaired renal function and high risk for iodinated contrast adverse reaction. We report two cases of acute renal failure caused by gadolinium (0.6 and 0.9 mmol/kg of body weight) after the execution of digital subtraction angiography (DSA) to produce diagnostic-quality images in two elderly diabetic patients with pre-existing renal insufficiency. Both patients needed dialysis treatments for as long as a few weeks until their renal function improved. In our opinion, and according to the guidelines of European Society of Urogenital Radiology, gadolinium has not been assessed as less nephrotoxic than iodinated contrast agents. In fact, 1.8 to 4.8 g of iodine, equally attenuated with a relatively high dose (0.2 to 0.4 mmol) of a gadolinium chelate, is a low iodine dose and could hardly have any important nephrotoxic effects. CONCLUSIONS: The maximum dose of gadolinium-based contrast agents should never exceed 0.2 to 0.4 mmol/kg in azotemic patients who are undergoing DSA, even though these doses of gadolinium may not provide images of suitable quality for diagnosis and intervention.

[Local therapy with platelet-derived growth factors for chronic diabetic ulcers in haemodialysis patients]. / Terapia locale con fattori di crescita piastrinici nelle ulcere croniche diabetiche in emodializzati.

BACKGROUND: The increasing number of diabetic patients who need dialysis treatment is the cause for the growing interest of nephrologists in ulcers of the lower limbs. It has been reported that platelet-derived growth factors, such as PDGF and TGF beta 1, are able to heal skin lesions due to diabetes. Therefore, a platelet gel (PG) has been developed to locally treat foot ulcers with a limited number of applications (3+/-1.7). METHOLOGY AND PATIENTS: The PG is a mix of concentrated platelets and cryoprecipitate activated by batroxobin in the presence of calcium chloride (or gluconate) that must be applied to the wound for three days. The surgeon and the dermatologist should then plan successive treatments because the necrotic tissue needs to be removed. We treated a 62-year-old diabetic man, who has been under treatment with insulin since the age of 36 and has been dialysed for three years. His right lower leg was amputated and he developed a chronic left foot ulcer that resulted in many septic episodes. His ulcer recovered in two months after 8 PG applications. CONCLUSIONS: Conventional therapy is not successful in 15-20% of diabetic feet. Uraemia and malnutrition may represent important risk factors for foot ulcers in diabetic patients who need advanced technology to stimulate tissue repair. The use of platelet growth factor may ameliorate ulcer healing thus reducing disease-associated morbidity and lowering health care costs.

The self-locating catheter: clinical evaluation and comparison with the Tenckhoff catheter.

BACKGROUND: Peritoneal catheter displacement appears to be related to various causes including omental attachment, bowel contractions, peritoneal adhesions, and the catheter floating in the dialysis fluid. In order to prevent this complication, which can impair peritoneal dialysis efficacy, Di Paolo et al. designed a "self-locating catheter" (SLC) that is similar to the Tenckhoff catheter (TC) and includes a small tungsten cylinder (weight 12 g) at the distal end (Di Paolo N, et al. The self positioning catheter. Proceedings of the VII Italian Congress on Peritoneal Dialysis. Milan: Wichtig Editore, 1993:539-42). The weight of the tip prevents the catheter from floating and migrating by gravitation toward the Douglas cavity. OBJECTIVE: Starting in 1996, we implanted SLC in 15 continuous ambulatory peritoneal dialysis patients. The aim of our study was to compare the ratio of migration and other catheter-related complications between patients with SLC (196 patient-months) and 13 patients with conventional straight TC (295 patient-months). RESULTS: Peritonitis ratio, catheter complication rate, dialysate inflow and outflow, and weekly creatinine clearance were similar in the two groups of patients. The incidence of catheter displacement was significantly higher (p = 0.0349) in theTC group than in the SLC group (4 vs 0). CONCLUSION: In our experience, the SLC seems to be useful in preventing catheter migration by continuous gravitation of its extremity toward the pelvic cavity.

Risk factors of ischemic cardiac disease in patients on continuous ambulatory peritoneal dialysis.

Elevated plasma levels of fibrinogen, factor VII coagulant activity (F VIIc), and plasminogen activator inhibitor (PAI-1) have been reported to be strictly associated with thrombotic events and are considered to be important risk markers of atherothrombotic cardiovascular disease. Therefore, we evaluated in 15 patients on continuous ambulatory peritoneal dialysis (CAPD) the plasma levels of these coagulation factors, basal insulin values, and the lipid pattern in comparison with 33 hemodialysis (HD) patients and 59 healthy subjects. In CAPD the total cholesterol and triglyceride results were significantly increased, but no difference was found in HDL cholesterol. Fibrinogen and F VIIc results were significantly higher in CAPD and HD than in the control group, probably due to an increased hepatic synthesis as a nonspecific response to the peritoneal protein loss. Elevated F VIIc activity may be caused by the presence of large negatively charged lipoproteins, in vivo thrombin formation, or reduced hepatic clearance. Both PAI 1 and t-PA results were higher in CAPD, probably due to an increased synthesis by endothelial cells activated by glucose peritoneal absorption and hypertonic dialysis solutions. The contemporary elevation of fibrinogen, F VIIc, PAI-1, and t-PA suggests that CAPD patients present a hypercoagulability and hypofibrinolysis condition, which may promote the development of atherothrombotic events.