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J Ahonen

Publications and source records attributed to J Ahonen.

At least 91 records · Page 5Linked to original sources
PubMed1994

Improved outcome of renal transplantation in amyloidosis.

We report our results in 96 patients with amyloidosis who received 105 cadaveric renal allografts. The graft survival of amyloidosis patients has improved with time and with improved immunosuppression. The graft survival of amyloidosis patients is comparable to the results in another systemic disease, i. e., diabetes, and only slightly inferior to those in primary renal disease, even though amyloidosis patients tolerate complications poorly and the patients are at high risk of dying during the first 3 months.

Adolescent↗
PubMed1994

Relationship between renal histology and later graft outcome.

We have created the chronic allograft damage index (CADI), which quantifies the early histopathological changes in renal allografts. In this study we showed that the CADI at 2 years after renal transplantation predicted the graft outcome 4 years later and that the CADI identified the risk group that proceeded to chronic rejection during subsequent years.

Biopsy↗
PubMed1994

Thirty years of renal transplantation in Helsinki.

During triple-drug immunosuppression, consisting of azathioprine, steroids, and cyclosporine, the number of acute rejections was low. Close monitoring of the patient and the graft during the early posttransplant weeks with regular cytological and histological analyses was the cornerstone of early diagnosis and a favorable outcome of acute rejection. Genetic homogeneity of our patient population, third-party transfusion program, and use of well HLA-matched kidney grafts may have been additional factors behind the low rate of acute rejection. Acute rejection within the first three postoperative months did not predispose the renal graft to chronic rejection in the long term. The histologically determined allograft damage index was a reliable predictor of future graft survival. Recipients with systemic diseases such as diabetes and amyloidosis, as well as elderly patients, could be transplanted safely with results only slightly inferior to those achieved with primary kidney disease. Results in diabetic recipients have steadily improved, encouraging the continuation of critical evaluation of the patients' pretransplant status and the preference for cadaveric transplants. Renal transplantation in small children yielded superior patient and graft survival rates. We consider the use of living donors justifiable in these cases. The five million population of Finland offers an ideal size for a transplant center. Continuous education of medical personnel and the general public is crucial for the cadaver transplant program.

Adolescent↗
PubMed1994

[Organs for transplantation. The demand increases--but not the supply].

The supply of organs is the only factor which limits the scope of transplantation to help the severely ill. As the number of donors can not be appreciably increased, the functional and medical criteria for donors are reduced instead. Although the already positive attitude of the public to cadaveric organ donation is unlikely to improve further, intensified information campaigns might result in more people discussing organ donation with their relatives and informing them of their views, which would help surviving relatives to decide for or against organ donation. It should also be possible to improve access to organs by educating health care personnel.

Adolescent↗
PubMed1994

Cadaveric organ donation in Scandinavia, 1992.

In countries with active organ transplant programs and wide acceptance criteria for transplant recipients, such as the four Scandinavian countries, the need for organ grafts has outgrown the supply of cadaveric organs. We cannot expect to attain the maximum number of cadaveric donors every year and in every procurement area because the number of donors depends not only on the efficacy of the procurement program but also on the age of the population, incidence of road traffic accidents, treatment facilities, and other factors. The maximum numbers are set as a goal to strive for, however, Countries that participate in an exchange of cadaver organs to obtain well-matched kidneys for uremic patients and life-saving grafts at a suitable time for heart, lung, and liver recipients, must all have the same approximate number of cadaver donors. Major imbalances in the number of donors and also in the number of patients waiting for a transplantation may result in the supply of organ allografts for one country or region being met by the population of another region. With confidence we are looking forward to the impact of intensified public information and education of hospital personnel on the gap between demand and supply of organ allografts.

Attitude↗
PubMed1994

Reversed diastolic blood flow at duplex Doppler. A sign of poor prognosis in renal transplants.

In 25 renal allografts out of 253 with graft dysfunction a reversed diastolic blood flow was observed at duplex ultrasonography during the first post-transplant month. Eleven grafts were lost and 14 survived. The cause of graft loss was arterial thrombosis (n = 1), venous thrombosis or obstruction (n = 4), steroid resistant acute rejection (n = 4) and acute tubular necrosis (ATN) (n = 2). The cause of graft dysfunction in the surviving grafts was ATN (n = 7) and acute allograft rejection (n = 7). Grafts with only peak-like or low velocity continuous diastolic flow reversal had a better prognosis (3 out of 15 were lost) than grafts with any other type of reversed flow pattern (8 out of 10 were lost). This difference was statistically significant (p < 0.01).

Biopsy, Needle↗
PubMed1993

Long-term consequences of different immunosuppressive regimens for renal allografts.

The long-term effects of four different immunosuppressive regimens on renal allografts have been investigated up to four years. A total of 128 recipients of first cadaveric renal allograft were randomized, after an initial induction period, to receive either triple drug therapy--i.e., (low-dose) cyclosporine, azathioprine, and methylprednisolone, or any possible combination of two drugs--i.e., Aza plus CsA, Aza plus MP, and CsA plus MP. The actual four-year graft survival rates for the triple therapy, Aza plus CsA, Aza plus MP, and CsA plus MP groups were 72%, 69%, 75%, and 59%, and patient survival rates were 78%, 81%, 81%, and 84%, respectively, with no significant differences. The cumulative number of chronic rejections up to 4 years was 0.09, 0.29, 0.25, and 0.34 per patient per group (P = ns), respectively. At 2, 3, and 4 years posttransplantation, the graft function was significantly worse in the Aza plus MP group compared with the triple therapy group (P < .05). Of the 98 patients who did not have type I or II diabetes at the time of transplantation, 17 developed posttransplantation diabetes mellitus or an abnormal glucose tolerance test within 2 years posttransplantation. All these patients had received steroids and none of the patients without steroids had these abnormalities. At two years the mean cholesterol level was highest in the Aza plus MP group, 6.8 mmol/L and lowest in the group receiving triple therapy, 5.8 mmol/L (P = ns). The use of (low-dose) CsA was not associated with lipid abnormalities or with disturbances in glucose metabolism. A protocol graft biopsy was performed at two years on all functioning kidneys, and the histological changes were scored blindly. No CsA-specific changes, except isometric vacuolation in tubuli, were found. Histological alterations characteristic of chronic rejection were expressed as "chronic allograft damage index." Chronic allograft damage index was lowest in the triple therapy group, 1.5, compared with the other groups, 3.2-4.3 (P = .01), indicating the least histopathological change in the triple therapy group. In conclusion, this long-term study did not show any serious cyclosporine-related side-effects when used in low dose in combination with two other drugs. Some side-effects, such as posttransplant diabetes mellitus and probably some lipid abnormalities, could rather be traced to a higher dose of steroids. Moreover, the triple drug therapy was more efficacious than any double drug regimen in the prevention of chronic histological changes in renal allografts.

Adult↗
PubMed1992

Late histopathological findings in renal allografts with four immunosuppressive regimens.

The histological changes in renal allografts are usually studied when graft function has already deteriorated. The early results of renal allografts have improved dramatically during the last two decades, but the half-life of renal cadaveric allografts has remained unchanged at approximately 7 years. The mechanism of chronic rejection, and how to prevent it, is not known. We studied the histology of renal allografts under four different immunosuppressive regimens 2 years after transplantation. The aim of this study was to investigate whether histopathological changes exist in the renal allografts with relatively good and stable graft function. We also investigated whether there were differences in allograft histology between four immunosuppressive treatment groups 2 years after transplantation.

Azathioprine↗
PubMed1992

Acute rejection in kidney grafts with delayed onset of graft function. A duplex-Doppler study.

Forty-five kidney transplant recipients with delayed onset of diuresis due to acute tubular necrosis (ATN) were examined with duplex ultrasonography (DU). Resistive index (RI) was measured on the 4th post-transplant day. Eleven grafts (24%) developed acute rejection. Mean RI prior to rejection of the 4th postoperative day in these grafts was 0.97 and in the 34 grafts which did not develop rejection mean RI was 0.82. There were 2/26 rejections (8%) in the group of grafts with an initial RI below 0.9 and 9/19 rejections (47%) in the group of grafts with RI of 0.9 or above on the 4th post-transplant day. Six months postoperatively there were 2/26 nonfunctioning grafts in the group with lower initial RI values (less than 0.9) and 6/19 nonfunctioning grafts in the group with higher indices (greater than or equal to 0.9). In nonfunctioning grafts a high initial RI (greater than or equal to 0.9) indicates that these grafts will be prone to developing acute rejection.

Adult↗
PubMed1992

Alpha-human-ANP response to preanesthetic volume expansion and subsequent renal transplantation in diabetic and nondiabetic uremic patients.

alpha-Human atrial natriuretic peptide (ANP) concentrations were measured in 11 diabetic patients with uremia and in 16 nondiabetic uremic controls undergoing renal transplantation after preanesthetic volume expansion with 1000 ml saline solution within 10 min. Two diabetic and seven nondiabetic patients received grafts from living donors and the rest from cadaveric donors. Volume expansion induced a significant increase in the cardiac filling pressures (P less than 0.001), which were kept at that level especially at declamping, which was preceded by mannitol infusion. The baseline mixed venous ANP levels were significantly higher in the diabetic (252 +/- 6 pg/ml) than in the nondiabetic group (103 +/- 14 pg/ml; P less than 0.05). In the nondiabetic group, ANP increased to 177 +/- 40 pg/ml as a response to volume loading (P less than 0.05); it was not clearly changed in the diabetic group. Arterial ANP increased from 267 +/- 55 to 343 +/- 75 pg/ml in the diabetic group (P less than 0.05 and from 102 +/- 17 to 147 +/- 31 pg/ml in the nondiabetic group (P less than 0.05). During transplantation, mixed venous ANP decreased to 125 +/- 55 pg/ml in the diabetic and to 80 +/- 10 pg/ml in the nondiabetic group (P less than 0.001). About 30% of circulating ANP was taken up by the transplant irrespective of postoperative graft function. Two patients in each group showed delayed diuresis requiring postoperative dialysis therapy (22% of all cadaveric transplantations). ANP levels at declamping had no correlation to the outcome of kidney function.

Adult↗
PubMed1992

Reversal of steroid-induced insulin resistance by a nicotinic-acid derivative in man.

A recent report suggested that the glucose-free fatty acid (FFA) cycle may contribute to steroid-induced insulin resistance in rats, and that glucose tolerance could be restored to normal when FFA levels were lowered with nicotinic acid. To test this hypothesis in man, we measured insulin sensitivity (by euglycemic insulin clamp in combination with indirect calorimetry and infusion of tritiated glucose) before and after short-term administration of a nicotinic-acid derivative (Acipimox) in 10 steroid-treated, kidney transplant patients with insulin resistance. Thirty-five healthy subjects served as controls. Six of them received Acipimox. Total body glucose metabolism was reduced in steroid-treated patients compared with control subjects (41.7 +/- 3.3 v 50.0 +/- 2.2 mumol/kg lean body mass [LBM].min, P less than .05). The reduction in insulin-stimulated glucose uptake was mainly due to an impairment in nonoxidative glucose metabolism (primarily glucose storage as glycogen) (18.3 +/- 2.8 v 27.2 +/- 2.2 mumol/kg LBM.min, P less than .01). Acipimox lowered basal FFA concentrations (from 672 +/- 63 to 114 +/- 11 mumol/L, P less than .05) and the rate of lipid oxidation measured in the basal state (1.5 +/- 0.2 to 0.6 +/- 0.1 mumol/kg LBM.min, P less than .01) and during the clamp (0.7 +/- 0.2 to 0.03 +/- 0.2 mumol/kg LBM.min, P less than .05). In addition, Acipimox administration normalized total glucose disposal (to 54.4 +/- 4.4 mumol/kg LBM.min), mainly due to enhanced nonoxidative glucose metabolism (to 28.9 +/- 3.9 mumol/kg LBM.min) in steroid-treated patients (both P less than .05 v before Acipimox).(ABSTRACT TRUNCATED AT 250 WORDS)

Adrenal Cortex Hormones↗
PubMed1992

Nordic teleradiology development.

In the Nordic countries there are several reasons why teleradiology has been an interesting topic of research during the last years. The distances in rural areas are long, and radiology expert service is not available in every health centre which is able to provide X-rays. Also, the telecommunication network is on a very advanced level in the Nordic countries. The staff is well educated and they are used to operating with computers. This all means that the infrastructure to develop and use systems like teleradiology exists. This paper describes two separate systems developed in Norway and Finland. Their development has been in many respects the same. The common hardware and software features, as well as the differences and the clinical experiences, are discussed in this paper.

Computer Systems↗
PubMed1992

Histopathological findings in well-functioning, long-term renal allografts.

One hundred and twenty-eight patients with a first cadaveric kidney allograft participated in a prospective, randomized, clinical trial comparing triple treatment, consisting of initial low-dose cyclosporine (CsA), azathioprine (Aza) and methylprednisolone (MP), with all possible combinations of two immunosuppressive drugs. A protocol core biopsy was performed on all patients with a functioning graft two years after transplantation. The histological findings were evaluated blindly and correlated to possible risk factors for renal allograft damage. The most common histological features were diffuse fibrosis in 62% of biopsies, tubular atrophy in 64% and diffuse inflammation in 30%. Two other important findings were glomerulosclerosis (43%) and vascular intimal proliferation (36%). The histological findings were scored mostly mild. A total of 77% (69 of 89) of patients had normal or only slightly increased serum creatinine. Decreased graft function was related to increased interstitial fibrosis, inflammation, glomerulosclerosis, mesangial matrix increase of glomeruli, intimal proliferation of vessels and tubular atrophy. These findings are characteristic, but not pathognomonic, of chronic renal allograft rejection both in experimental models and in humans. Possible risk factors were correlated to graft histology. Donor age correlated strongly with mesangial matrix increase, intimal proliferation, and tubular atrophy; there was no correlation with interstitial changes. The number of acute rejections and cold ischaemia time did not correlate with any one of the histological findings at two years following transplantation. Cyclosporine dose and concentration had a negative correlation to interstitial inflammation. A "chronic allograft damage index" was eventually created for the comparison of the four different treatment groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Clinical presentation and outcome of listeriosis in patients with and without immunosuppressive therapy.

Seventy-four cases of systemic listeriosis occurring from 1971 to 1989 in the greater Helsinki area in Finland are reviewed with a special interest in the effect of preceding immunosuppressive therapy on the clinical presentation. Of these patients, 66% had an underlying disease, most commonly malignancy, diabetes mellitus, or renal transplantation, and 43% had received immunosuppressive therapy within 1 week before onset of listeriosis. Bacteremia and central nervous system infections (both in 43% of cases) were the most common clinical entities. The percentage of patients with meningitis was not greater among immunosuppressed patients (13/32, 41%) than among patients with underlying diseases not treated with immunosuppressive agents (9/16, 56%) or among previously healthy nonpregnant hosts (7/11, 64%). Immunosuppressed patients did not die more frequently than did those with underlying diseases not treated with immunosuppressive therapy (case fatality rate, 29% vs. 38%, respectively). However, all previously healthy non-neonatal patients survived, whereas 32% (15/47) of those with any kind of underlying disease succumbed.

Adolescent↗
PubMed1992

Renal transplantations from the same kidney donor: outcome of diabetic and non-diabetic patients.

Diabetic (DM) nephropathy is an indication of renal transplantation in 30% of all cases in our hospital. We assessed retrospectively the outcome of these diabetics (DM) in comparison with their non-diabetic (NDM) controls. Each diabetic (n = 24) had a control (n = 24) receiving a kidney from the same donor. There was no difference in the stage of uraemia preoperatively. Anaesthesia and fluid therapy were standardized. Peroperative hypotension occurred more often in diabetics (NS). All operating parameters including cold ischaemia were comparable. Kidney function started immediately in 14/24 in the DM group and 13/24 in the NDM group and was delayed in 10/24 and 11/24, respectively. One diabetic patient rejected the transplant as did two non-diabetic patients. Postoperatively diuretics could be discontinued more often in the DM than in the NDM group (p < 0.05). Antihypertensives had to be started in the NDM more often (NS) than in the DM group. In conclusion, the outcome of diabetic patients after renal transplantation was comparable to their NDM controls.

Adult↗