The influence of blood transfusion on cellular immunity.

To evaluate the effect of transfusion on immunity, we studied some immunological parameters in 14 uremic patients treated with 3 blood transfusions (5 with HLA-compatible and 9 with random transfusions). Before transfusions 8/14 patients were DNCB-negative; both spontaneous and active E-rosettes were below normal range. The parameters of humoral immunity (S-Ig, C3, C4, IC, CRP) were normal. After both the first and second transfusions an increase in T- and B-lymphocytes was found. The third transfusion led to a more pronounced and prolonged immunosuppression in patients treated with compatible transfusions than in those treated with random transfusions. Our findings suggest that blood transfusion--HLA-compatible transfusion in particular--results in an impairment of the lymphocyte role.

Impact of co-amoxiclav on polymorphonuclear granulocytes from chronic hemodialysis patients.

Phagocyte-dependent host defenses are frequently impaired in maintenance hemodialysis patients who show an increased susceptibility to infections. In these individuals, the course of infections can be more aggressive than in normal hosts, and the antibiotic of choice should have a high antimicrobial effect without impairing host defenses. Hence, in uremic patients, the antibiotic enhancement of phagocyte functions may be of potential clinical importance in the outcome of bacterial infections. Because we demonstrated previously that co-amoxiclav had beneficial properties that result in enhancement of the microbicidal functions of human polymorphonuclear cells (PMNs) from healthy subjects, we investigated the influence of this combination on the activities of PMNs from chronic hemodialysis patients against Klebsiella pneumoniae, a human pathogen that can pose severe problems in patients whose immunity is impaired. PMNs from chronic dialysis patients showed a diminished in vitro phagocytic efficiency with a reduced phagocytosis and bactericidal activity towards intracellular K. pneumoniae compared with that seen in PMNs from healthy subjects. When co-amoxiclav was added to PMNs from chronic hemodialysis patients, it was able to restore the depressed primary functions of PMNs, resulting in a significant high increase in both phagocytosis or killing activity. A similar pattern was detected with PMNs collected from hemodialysis patients treated with co-amoxiclav. The results of the present study provide evidence that co-amoxiclav is able to induce stimulation of depressed phagocytic response of PMNs from patients on chronic hemodialysis, restoring their primary functions both in vitro and in vivo.

Death in conditions of cachexia: the price for the dialysis treatment of the elderly?

Death in conditions of cachexia is increasing in potential dialysis patients, as treated cohorts are aging, the mean age of new patients increased and access to treatment is unlimited. The present study analyzes the clinical features of 417 deaths in conditions of cachexia recorded in 1981 to 1990 in the Dialysis and Transplantation Registry of a northern Italian region, Piedmont (about 4,400,000 inhabitants, 20 dialysis centers; 4,734 patients on file at December 31, 1990; yearly information on 100% of the cases). Death in conditions of cachexia increased from 105 cases in the first four years taken into account (1981 to 1984), to 107 in the last two years (1989 to 1990). Prevalence is higher in the elderly (85% of the death over age 60). Most patients (90.5%) were at high clinical risk. To assess whether the frequency of this diagnosis reflected the wide acceptance of elderly patients for dialysis and was a marked of vascular disease, a specific inquiry was conducted about 107 cachectic deaths recorded from 1989 to 1990: 82.5% of the patients had diffused vascular disease, 11.5% were already cachectic when dialysis was initiated, and 66% were in cachexia at least six months before death. Since mean age of patients dying in condition of cachexia increased from 68.8 in the period of 1981 to 1984 to 70.3 years in 1989 to 1990, and mean time on dialysis from 2.8 years in 1981 to 1984 to 70.3 years in 1989 to 1990, the higher prevalence is not likely to be due to lack of care of elderly patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Cerebral vasoreactivity does not predict cerebral ischaemia during carotid endarterectomy.

AIM: Assessment of cerebrovasoreactivity (CVR), obtained by transcranial Doppler (TCD) and the acetazolamide test to predict cases requiring selective carotid shunting on the basis of neurologic monitoring. METHODS: A consecutive series of 87 carotid endarterectomy (CEA) cases was studied. Before surgery CVR was evaluated by measuring the mean velocity of the middle cerebral artery (mvMCA) using TCD at the basal condition and at 30 min after intravenous administration of acetazolamide (1 g). Carotid shunting was performed using neurologic monitoring under local anesthesia. Receiver operating characteristic (ROC) curve was calculated for sensitivity and specificity for various CVR cut offs. RESULTS: The ROC curve demonstrated that there was no single CVR cut off with both sensitivity and specificity above 80%. CONCLUSION: The present study, which employed neurologic monitoring as the method of comparison, did not prove that CVR, as calculated by TCD and the acetazolamide test, is a valid preoperative test for predicting cerebral ischaemia caused by carotid clamping.

Predictive value of transcutaneous oximetry for selection of the amputation level.

BACKGROUND: Transcutaneous oximetry was studied to select the correct amputation level for limb ischemic necrosis with possible identification of threshold value. METHODS: The method was evaluated in 30 cases (20 patients, 5 males and 15 females, of ages ranging from 61 to 93, average 73.1+/-8.5) where patients underwent amputation because of severe leg ischemia. Surgical operations were: minor amputation (toe or transmetatarsal) in 23 cases, below knee amputation in 7. Oxygen tension was measured at the dorsum foot and at the third superior of the anteromedial calf aspect. RESULTS: Results were classified as success (primary or delayed healing) or failure (necrosis at the surgical wound). Amputation was successful in 17/30 cases with oxygen tension of 0-65 mmHg (mean 32.5+/-16.1) and failed in 13/30 with oxygen tension of 0-57 mmHg (mean 7.8+/-17.3). The difference was statistically significant (p=0.0004). Sensitivity of the method resulted 88.2%, specificity 84.6%, diagnostic accuracy 86.7%, positive predictive value 88.2% and negative predictive value 84.6%. A threshold of 20 mmHg was identified: 15/17 successful cases showed values greater than 20 mmHg, while 11/13 failed cases presented values lower than the threshold. CONCLUSIONS: Following our observations and according to some reported studies, we believe transcutaneous oximetry to be the best method for selection of amputation level This is a simple, noninvasive and accurate method, which has showed itself superior to other techniques (i.e., Doppler and radioisotope).

Lymphocyte subsets assayed by numerical tests in CAPD.

Peripheral and peritoneal lymphocytes were assayed by numerical tests in adults on peritoneal dialysis. T lymphocytes were classified by monoclonal antibodies (OKT3, OKT4, OKT8) and B lymphocytes by the presence of surface immunoglobulins, using the immunofluorescence technique. Peripheral T cells showed no significant change from the normal, except for T suppressor cells which increased in patients with 2 or more peritonitis episodes. Examination of peritoneal lymphocytes showed a significant reduction in S-IgA lymphocytes (B cells bearing IgA receptors) and an increase in T-suppressor cells (OKT8+) in patients who developed peritonitis in the follow-up study. The implications of these results are discussed with particular reference to susceptibility to peritonitis.

[Automated peritoneal dialysis (APD). Experience in 42 patients]. / La dialisi peritoneale automatizzata (APD). Esperienza in 42 pazienti.

Automated peritoneal dialysis (APD) is currently considered as one of the most attractive home treatments for uremic patients. However, relevant costs and the presence of a dialysis machine prevent a wider diffusion of this technique. In this work we discuss the results obtained in 42 patients (12 females, 30 males) treated by two dialysis units of the Piedmont Region. Patients' characteristics. Eighty-three percent of the females and 66.5% of the males are under 65 years of age; glomerulo-nephritis and nephroangiosclerosis account for the most frequent renal diseases (28.5 each); a high risk condition is recorded in 52.5% of cases. Twenty-two patients were transferred to APD from CAPD (patient's request in 59% of cases, clinical problems in the remaining). RESULTS. Forty-five percent of cases are working full or part-time, 12% are not caring for self. Peritonitis rate accounts for 1 episode every 42 patient-months. Biochemical control is satisfactorily achieved (mean values: urea 137.8 mg/dl, creatinine 11 mg/dl, calcium 10.2 mg/dl, phosphate 5.7 mg/dl, albumin 4.3 g/dl, cholesterol 234 mg/dl, triglycerides 195 mg/dl). Technical assistance was requested on average once every 16 months of treatment. CONCLUSION. Negative drawbacks of APD, mainly related to elevated costs and technical complexity, are fully counterbalanced by satisfactory social and clinical rehabilitation, wider indications to peritoneal dialysis with respect to CAPD, lower rates of peritonitis and limited technical needs.

[Surgical interventions in dialysis patients in Piedmont: data from the Regional Registry. Working Group of the Piedmont Registry of Dialysis and Transplantation]. / Interventi chirurgici nei pazienti in dialisi in Piemonte: dati dal Registro Regionale (RPDT). Gruppo di lavoro dell'RPDT.

In this work surgical events in a large population of chronic dialysis patients are analysed. Data are obtained from the Regional (Piedmont) Registry of Dialysis and Transplantation (RPDT), that has collected information since 1981 about all chronic dialysis patients in the Region. Since 1984, causes of admission to-hospital are registered. Surgical causes of hospitalization, for purposes not related to uremia, were 538 (20% of all surgical admissions). In patients younger than 65 years, these hospitalizations account for about 6% of the cases, whereas in patients older than 65 they are less than 5%. As expected, a higher number of surgical operations is observed in diabetics, while on the contrary the lowest is performed in nephroangiosclerosis patients. Cardiovascular and bowel diseases represent almost 50% of all surgical needs. Postoperative mortality was 5.8% within 45 days from admission. Cardiac and infectious diseases and cachexia represent the more frequent causes of death. In 27 out of 28 cases at least one high risk condition was present.

CAPD in a large population: a 7-year experience.

In this report we evaluate the results obtained with CAPD in uremic patients in Piedmont, a Northern Italian region (4.4 million inhabitants) during the last 7 years. Data are gathered from the computerized records of the regional dialysis and transplantation registry, which collects information on 3,567 pts, 2,243 of which entered since Jan. 1981 and 1,808 alive at Dec. 1987. Among these, 193 (11%) were on CAPD, a figure almost constant in the last 7 years. However CAPD diffusion is not uniform among the 20 centers of the region, ranging from 0 to 49.5% of the patients on dialysis. CAPD is particularly employed in the elderly (47.5% of the patients being older than 60 years and 19.5% over 70). This treatment was the first choice in 16% of the patients admitted to dialysis between 1981-87; this figure reaches 33% for the diabetics. High drop out rates still represent a major problem, in a 6 year follow up 66% of the patients being transferred to another dialysis treatment. Peritonitis is the main cause of drop out (22%), while loss of peritoneal membrane efficiency accounts for 7%, patient's choice 14%, catheter complications 14%, inability to cope 8%, clinical problems 20% and other reasons 15%. Drop out rate is not influenced by the presence of high risk condition or age. Survival curves show no significant difference for CAPD in comparison to hemodialysis in all the age groups considered. This epidemiological survey, based on a global 522 pts experience extended over a 7 year period, indicates that CAPD is a competitive mode of treatment in chronic uremia.

Erythrocyte Na-stimulated Mg transport in uremic patients undergoing CAPD.

A derangement of magnesium homeostasis with hypermagnesemia and increased intraerythrocyte Mg content [Mgi] has been described in uremic patients, and could play a pathogenetic role in both alterations of bone metabolism and vascular reactivity, observed in these patients. Recently Féray and Garay described in human erythrocytes a transport system which catalyzes outward Mg movements in the presence of external Na. These fluxes may be responsible for maintaining and regulating a low [Mgi]. The aim of this study was to evaluate in 16 normal subjects and 14 uremic patients undergoing CAPD: [Mgi] and rate of Na-dependent and Na-independent Mg efflux in Mg-loaded erythrocytes, in order to maximally stimulate Mg efflux. Mean plasma and intraerythrocyte Mg concentrations were significantly higher in CAPD than in normal subjects (1.09 +/- 0.20 vs 0.86 +/- 0.004 mmol/l, p less than 0.001 and 2.57 +/- 0.38 vs 1.96 +/- 0.18 mmol/l RBC, p less than 0.001). After an in-vitro Mg load, the intraerythrocyte Mg concentration and Na-independent Mg efflux were similar in both groups (17.5 +/- 1.4 vs 18.2 +/- 4.1 mmol/l RBC and 152 +/- 20 vs 126 +/- 19 mumol/l RBC/h). However, the Vmax of erythrocyte Na-stimulated Mg efflux was significantly higher in CAPD patients than in normal subjects (357 +/- 48 vs 229 +/- 88 mumol/l RBC/h, p less than 0.02). [Mgi] and the rate of Na-dependent Mg efflux were inversely related in CAPD patients (r = -0.76; p less than 0.002). These results indicate that uremic CAPD patients have a [Mgi] and Vmax of erythrocyte Na-dependent Mg efflux higher than normal subjects; this could reflect a compensatory, although insufficient, mechanism against high levels of intraerythrocyte Mg concentration, as suggested by the correlation between [Mgi] and the rate of Na-dependent Mg efflux.