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J F Donohoe

Publications and source records attributed to J F Donohoe.

At least 19 recordsLinked to original sources

Sensitization to human leukocyte antigen before and after the introduction of erythropoietin.

INTRODUCTION: Antibodies directed against human leukocyte antigens (HLAs) impact adversely on renal transplantation. Measures aimed at preventing such antibody formation are thus important. The introduction of recombinant human erythropoietin (rHuEpo) has permitted the reduction of blood transfusion in patients with chronic renal failure. The impact of rHuEpo on the incidence of sensitization in patients awaiting transplantation was therefore studied. METHODS: A retrospective analysis of the patients awaiting transplantation before (group A) and 4 years after (group B) the introduction of rHuEpo was performed in order to ascertain changing patterns in the use of blood transfusion and causes of sensitization. RESULTS: The total number of transfusions administered to haemodialysis patients decreased by 34% during the study period. This was accompanied by a significant reduction in the ratio of blood transfusion to haemodialysis treatment episodes (0.095 in group A to 0.06 in group B, P = 0.001). The number of patients sensitized as a consequence of blood transfusion decreased from 63% in group A to 28% in group B (P = 0.0004). The overall incidence of sensitization decreased from 50% in group A to 36.5% in group B (P = 0.008). This decrement was associated with a significant reduction in the mean waiting time for transplantation (42.1 +/- 1.1 vs 15.4 +/- 2.4 months, P < 0.0001). The incidence of sensitization due to previous transplantation increased during the study period from 41% in group A to 77% in group B, (P = 0.0004). There was no change in the number of patients sensitized due to pregnancy. CONCLUSION: The introduction of rHuEpo has resulted in a significant decrease in the requirements for blood transfusion among patients awaiting transplantation and is associated with a significant reduction in transfusion-related sensitization and mean waiting time for transplantation.

Blood Transfusion↗

Prolonged survival with a remnant kidney.

Surgical ablation of five-sixths renal mass in Munich-Wistar rats fed a high protein diet leads to focal sclerosis in the remnant kidney and progressive renal failure. Experimental data suggest that this injury results from intraglomerular hypertension and/or chronic glomerular hyperfiltration. Data in humans largely are limited to patients with unilateral renal agenesis or uninephrectomy, either for unilateral renal disease or for kidney transplant donation. Isolated case reports have documented focal sclerosis and progressive renal failure in two patients with a remnant kidney. To obtain data in humans with a remnant kidney, we surveyed more than 800 urologists and nephrologists in the United States and abroad. Criteria for inclusion in the study were (1) surgical resection (in one or more operations) resulting in the presence of a remnant kidney; and (2) an adequate period of follow-up, defined as 5 years or greater. A total of 13 patients were identified (from 13 different centers). Twelve patients had renal cancer and one had tuberculosis. Six patients were observed for 10 or more years postoperatively and all have stable serum creatinine levels of less than 270 mumol/L (3.0 mg/dL); two of these six patients are now more than 25 and 30 years postoperation. The other seven patients, observed for 5 to 7 years, have serum creatinine levels less than 270 mumol/L (3 mg/dL), while one has an increasing serum creatinine level. The two longest surviving patients both have undergone successful pregnancy with no overall change in serum creatinine. These observations demonstrate that it is possible for humans to survive more than 30 years with a stable serum creatinine, despite the presence of only a remnant kidney.

Adult↗

Lisinopril in the treatment of hypertensive patients with renal impairment.

Lisinopril, a long-acting angiotensin-converting enzyme inhibitor, is excreted unchanged by the kidney. To determine how reduced renal function affects the drug's antihypertensive efficacy and safety, we studied 26 patients with hypertension associated with impaired renal function, having glomerular filtration rates (GFRs) of 60 ml/minute or less. These patients were enrolled in an open trial of 12 weeks' duration. They were given single daily doses of lisinopril, starting with 2.5 mg in patients with a GFR of less than 30 ml/minute, and 5 mg in the other patients. The dose was titrated to a maximum of 40 mg daily according to the blood pressure response. A diuretic was then added if required. Mean sitting and standing blood pressures at four, eight, and 12 weeks of treatment were significantly reduced compared with pretreatment values. The median dose of lisinopril was 10 mg daily (range, 2.5 to 40 mg), and only four patients required the addition of a diuretic. The mean GFR was unchanged during the study (36 +/- 16.4 ml/minute at baseline, 39 +/- 20.8 ml/minute after 12 weeks of treatment). Twenty-five patients completed the study. The one patient withdrew because of nausea and vomiting due to reflux esophagitis, which was probably not drug-related. Another patient had transient angioneurotic edema and continued to receive lisinopril. No clinically significant hematologic or biochemical abnormalities were observed. Sixteen patients continued to receive lisinopril for one year. Blood pressure control and GFR were well maintained throughout. Thus, in a group of patients who are often difficult to treat, lisinopril provided highly effective blood pressure control and was generally well tolerated.

Adult↗

Antihypertensive and renal effects of lisinopril in older patients with hypertension.

The antihypertensive efficacy and safety of lisinopril were assessed in 60 older patients with a mean age of 75 years (range, 65 to 85 years) in a 12-week open study. Mean ( +/- SEM) blood pressure while sitting was reduced from 190/106 +/- 3.3/1.8 mm Hg at entry to 162/89 +/- 3.2/1.6 mm Hg after 12 weeks of treatment (p less than 0.001). There was no significant alteration in heart rate, and postural hypotension did not occur. Mean glomerular filtration rate at entry was 61.6 +/- 3.4 ml/minute and was unchanged after 12 weeks of therapy at 62.2 +/- 3.0 ml/minute. Fourteen patients continued to receive lisinopril for a period of one year. Blood pressure remained controlled throughout and heart rate remained unchanged. There was a significant reduction in mean arterial pressure from 128.8 +/- 1.9 mm Hg to 105.1 +/- 1.5 mm Hg (p less than 0.001). Biochemical parameters remained unaltered. There was a significant increase in renal blood flow (p less than 0.025) and a corresponding reduction in renovascular resistance (p less than 0.001) following long-term therapy with lisinopril. Thus, lisinopril was generally well-tolerated and highly effective in lowering blood pressure in older hypertensive patients, whereas at the same time renal function was not adversely changed.

Aged↗

Pharmacokinetics of amlodipine in renal impairment.

The pharmacokinetics of amlodipine was studied in 27 subjects with renal function ranging from normal to dialysis-dependent. Amlodipine (as a single 5-mg capsule) was administered once daily for 14 days and its plasma concentrations were measured by gas chromatography during and after treatment. Renal impairment had little or no effect on the pharmacokinetics of amlodipine. The elimination half-life was of the order of 50 h, similar to previously observed values, and did not vary with differences in renal function. Steady-state predose concentrations were observed after the ninth dose. Accumulation of amlodipine to steady-state levels was not significantly different from that expected on theoretical grounds and did not significantly change with renal function. These results suggest that once-daily administration of amlodipine is suitable for all degrees of renal function and that dosage adjustment is not necessary in renal impairment.

Adult↗

Lisinopril in hypertension associated with renal impairment.

The antihypertensive efficacy and safety of lisinopril, a long-acting angiotensin-converting enzyme inhibitor, were assessed in 23 patients with hypertension associated with impaired renal function (glomerular filtration rate 60 ml/min or less) in an open study of 12 weeks' duration. Lisinopril was given orally in single daily doses. The starting dose was 2.5 mg in patients with glomerular filtration rate (GFR) of less than 30 ml/min and 5 mg in all other patients. This was titrated to a maximum of 40 mg daily according to blood pressure response. A diuretic was then added if blood pressure was not controlled. Mean sitting and standing blood pressures were significantly reduced by lisinopril treatment. The median dose of lisinopril taken was 10 mg daily (range 2.5-40 mg), and only three patients required the addition of a diuretic. The mean glomerular filtration rate was unchanged during the study (38 +/- 16.4 ml/min at baseline, 41 +/- 21.0 ml/min after 12 weeks of treatment). Twenty-two patients completed the study. One patient was withdrawn because of nausea and vomiting due to reflux oesophagitis which was probably not drug related. Another patient had transient mild angioneurotic oedema and continued on lisinopril. No clinically significant haematological or biochemical changes were observed. In conclusion, lisinopril provided effective blood pressure control and was well tolerated in this group of hypertensives who are typically difficult to treat.

Adult↗

Lisinopril treatment of hypertension in patients with impaired renal function.

Lisinopril is a new, long-acting, nonsulfhydryl angiotension-converting enzyme (ACE) inhibitor that is excreted unchanged by the kidney. The antihypertensive efficacy and safety profiles of lisinopril were assessed in 24 patients (15 men, 9 women; mean age 52.3 years; range 21-75 years) with hypertension associated with impaired renal function (glomerular filtration rate GFR 60 ml/min or less), in an open study of 12 weeks' duration. Previous antihypertensive drugs were discontinued at entry into the study. Lisinopril was given orally once daily; the starting dose was 2.5 mg in patients with a GFR of less than 30 ml/min, and 5 mg in all other patients. The dosage of lisinopril was titrated upward to 40 mg daily according to BP response. A diuretic could then be added if hypertension was inadequately controlled. Twenty-three patients completed the study. Mean sitting BP was reduced from 177 +/- 21.2/106 +/- 9.1 mm Hg (mean +/- SD) at entry to the study to 145 +/- 21.4/88 +/- 8.3 mm Hg after 12 weeks of treatment (p less than 0.001). The median dose of lisinopril used was 10 mg (range 2.5-40 mg) and only 4 patients had a diuretic added to the lisinopril. Overall GFR was unchanged during the study: mean baseline value was 37 +/- 16.4 ml/min (range 10-60 ml/min) at the beginning of the study and 40 +/- 21.0 ml/min at the end. As in a previous pharmacokinetic study in similar patients, a tendency toward drug accumulation was noted only in those patients with the most severe renal impairment.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Aluminum-related bone disease. Correlation between symptoms, osteoid volume, and aluminum staining.

In order to correlate symptoms, osteoid volume, and aluminum deposition in bone, 46 methacrylate-embedded biopsy specimens from 26 hemodialysis patients were examined. Osteoid volume was measured using computer-assisted morphometric analysis, and aluminum was detected using the Aluminon stain. Positive staining for aluminum was present in biopsies from 21 patients. Osteoid volume did not correlate with duration of dialysis therapy or ingestion of aluminum hydroxide but displayed a logarithmic relationship with dialysate aluminum exposure. Patients with bone pain at the time of biopsy had a greater degree of hyperosteoidosis than asymptomatic subjects. Osteoid volume in patients with fractures and positive aluminum staining decreased on withdrawal from aluminum-rich dialysate. The Aluminon staining technic is a convenient method of confirming aluminum overload.

Aluminum↗

Clinical experience with aztreonam in urinary and respiratory tract infections.

Twenty patients with severe infection, 10 of the urinary tract and the other 10 of the respiratory tract, were enrolled in a clinical trial of aztreonam, a new monobactam antimicrobial agent. For the urinary tract infections, the mean duration of treatment was 7 days, with doses ranging from 0.25 to 1.0 g aztreonam intravenously twice daily. Sustained clinical and microbiological cure was achieved in 9 of the 10 patients. In the group with respiratory infections, the mean duration of treatment was 9.3 days, patients receiving 1 g aztreonam intravenously 3-times daily. Initial clinical cure was achieved in 9 of the patients, the tenth showing an incomplete response. However, bacteriological recurrence, related to the persistent nature of the underlying disease, occurred in 6 of the 10 patients during the 1-month follow-up period. The only side-effects were mild, transient biochemical abnormalities which did not require drug withdrawal in any patient.

Adult↗

Effect of volume expansion on hemodynamics of the hypoperfused rat kidney.

The hemodynamics of the rat kidney were studied during reduction of renal arterial pressure to 35-40 mm Hg (H), and after volume expansion at that pressure with 0.9% NaCl (IS), 1.7% NaCl (HS), 5% mannitol in 0.9% NaCl (MS), 5% mannitol in water (MW), or 50 mM mannitol + 125 mM NaCl. During H, left renal blood flow (RBF) was 0.8+/-0.1 ml/min. Expansion with IS did not alter RBF, but expansion with HS, MS, MW, and 50 + 125 mM NaCl elevated RBF to 200-250% of hypoperfusion values. Glomerular capillary pressure rose significantly from 15.7+/-0.7 mm Hg during H to 22.3+/-1.1, 24.4+/-0.7, and 26.6+/-0.7 mm Hg following expansion with HS, MS, or MW, respectively. Efferent arteriolar pressure also rose significantly to 6.9+/-0.5, 9.7+/-0.8, and 9.5+/-0.9 mm Hg, respectively. Preglomerular resistance fell to 18-24% of H values, and postglomerular resistance fell to 58-74% of H values after expansion with HS, MS, or MW. Glomerular filtration (GFR) could not be detected during H or after IS expansion. HS and mannitol-containing solutions restored GFR to 0.10+/-0.02-0.15+/-0.02 ml/min, and single nephron glomerular filtration to 6-12 nl/min. Papaverine, acetylcholine, and kinins had no effect on RBF or GFR at a perfusion pressure of 35-40 mm Hg. We conclude that mannitol and HS have the capacity to augment RBF during hypoperfusion by reducing arteriolar resistance. The mechanism of the rise in RBF is uncertain; it may be due to changes in effective osmolality of the extracellular fluid or to a direct action of mannitol on vascular smooth muscle. Other potent vasodilators were ineffective during hypoperfusion. Restoration of GFR occurs as a result of the combined effects of augmented RBF and elevated net filtration pressure.

Animals↗

Rapid recurrence of membranous nephropathy in a related allograft.

A patient with membranous nephropathy (MN) received a renal allograft from his brother. The allograft functioned immediately but nephrotic range proteinuria developed seven days after transplantation in the absence of any signs of rejection. Renal function deteriorated five weeks after transplantation due to ureteric obstruction. Nephrostomy drainage resulted in the return of renal function to normal and demonstrated that the allograft was the source of the nephrotic range proteinuria. An open renal biopsy of the allograft performed at the same time revealed the presence of recurrent MN. The recipient was investigated in an attempt to identify possible humoral immune mechanisms that may explain this very rapid recurrence of MN.

Adult↗