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H K Johnson

Publications and source records attributed to H K Johnson.

At least 37 records · Page 2Linked to original sources
PubMed1992

Colonic screening prior to renal transplantation and its impact on post-transplant colonic complications.

Colonic complications after renal transplantation are uncommon but have a high mortality rate. Some have recommended colonic screening in patients over 50 years of age prior to transplantation to lessen the impact of colonic diverticular disease. We report our 9-year experience of colonic screening for diverticular disease in potential recipients over the age of 50 and compare these results to the overall colonic complication rate in the same time period. From 1981-1990, 1186 renal transplants in 1019 patients were performed, during which time all potential recipients over the age of 50 yr were required to undergo colon evaluation prior to transplantation. Twenty cases of diverticular disease were found with more than a quarter of the cases in patients with adult polycystic disease. All underwent renal transplantation without a pre-transplant colectomy, and none had post transplant symptomatic colon disease. During that same time period a total of 14 colonic complications requiring surgical intervention were encountered with a mortality rate of 40%. Acute diverticulitis occurred in 5 patients, all of whom were over 50 yr of age, on low-dose immunosuppression, and in most cases it occurred remotely after transplantation. Colonic dysplasia/neoplasia also occurred remotely after transplantation in 2 patients over the age of 50. Cytomegalovirus (CMV) colitis was the next most common complication, accounting for 3 cases. This complication, which occurred in younger patients, was associated with high-dose steroid immunosuppression and had a high mortality rate, in spite of surgical intervention.(ABSTRACT TRUNCATED AT 250 WORDS)

Colitis↗
PubMed1991

Presymptomatic testing for adult onset polycystic kidney disease in at-risk kidney transplant donors.

Autosomal dominant adult-onset polycystic kidney disease (ADPKD) is estimated to have an incidence of 1/1,000 and accounts for approximately 10% of all end-stage renal disease in the United States. While relatives are attractive as renal donors due to their availability and the improved transplant success associated with living-related donors, they may coincidentally be at risk for ADPKD. Accurate presymptomatic testing for at-risk potential donors is critical for both the donor and the recipient. We report here 2 families in which presymptomatic testing for ADPKD was accomplished by DNA linkage analysis on several potential renal donors prior to transplant. This resulted in the protection of both donors and recipients by preventing the transplantation of a kidney affected by ADPKD. Thorough counseling prior to DNA analysis (including discussion of accuracy and possible testing outcomes of presymptomatic diagnosis of ADPKD, diagnosis of noncarrier status, false paternity, and non-informative study) was essential to provide informed consent and preserve confidentiality within the family. Confidentiality for potential donors found presymptomatically to be affected (with a 94% or greater probability) was especially difficult to maintain.

Female↗
PubMed1991

Single-center analysis of impact of immunosuppressive therapy upon renal allograft survival in the black population.

The effect of race upon renal allograft survival is controversial. Between 1981 and 1987, at Vanderbilt University Medical Center, 448 patients (75 black, 373 white) received azathioprine, 3 mg/kg daily; prednisone, 30 mg daily; and intravenous antithymocyte sera, 0.2 mL/kg/day for 14 days, after transplantation. Prednisone doses were decreased gradually to 10 mg daily within 6 months of transplantation. Azathioprine was maintained at doses of 2 to 3 mg/kg/daily; lower doses were administered if significant myelosuppression occurred. One-year graft survival was 72% and 85% among black and white recipients, respectively (P less than .01). Two hundred thirty-six patients have been treated with azathioprine (3 mg/kg initially tapered during the first week to 1.5 to 2 mg/kg); prednisone, 30 mg daily; and cyclosporine, 10 mg/kg per day. Cyclosporine therapy was begun after recipient serum creatinine levels had decreased below 3 mg/dL. Before therapy was initiated and until levels of cyclosporine were maintained between 150 and 200 ng/mL (whole blood), antithymocyte serum was administered. This immunosuppressive protocol resulted in 1-year graft survival of 90% and 87% in black and white recipients, respectively. Not only was graft loss markedly reduced, but the interracial difference noted before the use of cyclosporine was no longer evident. The type of immunosuppressive therapy used clearly affected 1-year allograft survival among black recipients. The combination of azathioprine, cyclosporine, and prednisone resulted in improved graft survival overall, but had the most significant effect among blacks.

Azathioprine↗
PubMed1989

Duplex Doppler sonography of renal transplants. Correlation with histopathology.

The correlation of histopathologic findings with duplex Doppler sonography (DDS) in 24 biopsies in 21 patients was studied. The resistive indices (RI) of the acute rejection group were statistically different (p = .04) from those that were negative for rejection or clinical controls. Although the number of cases of moderate to severe interstitial and/or vascular rejection was relatively small compared to the mild group, patients with the more severe forms of rejection (moderate to severe interstitial with or without vascular rejection) tended to have higher RIs (.89 +/- .04) than those with the milder forms of rejection (.75 +/- .05).

Biopsy↗
PubMed1988

Vascular control of brain cooling in reindeer.

The cold venous effluent returning from the nose of the heat-stressed reindeer may be distributed through angular oculi veins for selective cooling of the brain and through facial veins for general body cooling. In vitro experiments indicate that adrenergic receptors of the angular oculi vein are exclusively of the alpha-adrenergic type, whereas facial veins contain mainly beta-adrenergic receptors. We suggest that the antagonistic adrenergic neuroeffector organization of these veins plays a major role in control of brain cooling. Thus simultaneous sympathetic stimulation results in constriction of angular oculi veins and release of a preexisting stretch-induced tone in facial veins. In this situation cold venous blood is directed via facial veins and used for general body cooling. Reduction of sympathetic activity, on the other hand, results in dilatation of angular oculi veins and constriction of facial veins, due to development of myogenic tone in the latter vessels. In this situation cold venous blood is distributed via angular oculi veins and used for selective cooling of the brain.

Animals↗
PubMed1986

Living related kidney donors. A 14-year experience.

Living related donor (LRD) nephrectomies are controversial due to the risks to the donor and improved cadaveric graft survival using cyclosporine A. Between December 22, 1970, and December 31, 1984, 1096 renal transplants were performed at a single institution, 314 (28.6%) from LRD. The average age was 34.3 years (range: 18-67); none had preoperative hypertension. All nephrectomies were performed transabdominally. Major perioperative complications occurred in 22 (7.0%). These include wound infections (3.5%), pancreatitis (1.0%), injuries to spleen (1.0%) or adrenal gland (0.3%) requiring removal, pneumonitis (0.6%), ulnar nerve palsy (0.6%), femoral artery thrombosis after arteriogram (0.3%), pulmonary embolus (0.3%), and upper pole infarct of contralateral kidney (0.3%). There are six known deaths in this series, none of which were related to the operation. Major late complications were seen in 50 (20.0%) of 250 patients followed for 6 to 175 months (mean 53.1 months). These included definite hypertension (5.6%), suture granuloma (4.4%), incisional hernia (3.6%), proteinuria (2.4%), bowel obstruction (2.0%), nephrolithiasis (1.2%), wound infection (0.4%), scrotal hydrocele (0.4%), and chronic pancreatitis (0.4%). While the risk of hypertension appears to increase as the interval from donation increases, no cases of renal failure after donation have been noted, and negligible proteinuria among those followed long-term has been seen in this series. It is felt that living related kidney donation is justified when the relative is sincerely motivated and well informed prior to donation.

Adolescent↗
PubMed1985

Renal transplantation. A 20-year experience in a Veterans Administration Medical Center.

Between March 1963 and December 1983, 324 renal transplants were performed in 273 veteran patients at the Veterans Administration Medical Center, Nashville, Tenn. Cadaver donors were used in 273 transplants, with an overall one-year patient survival of 72.5% and one-year functional graft survival of 50%. Twenty-four living-related transplants were performed, with an overall one-year patient survival of 89% and one-year functional graft survival of 75%. For analytical purposes the 20-year transplant experience was divided into five eras. One-year patient survival increased from 45% in era 1 to 84% in era 5, while functional graft survival increased from 45% to 70%. Death has occurred in 139 patients, with sepsis being responsible for the largest number of early deaths. Cardiovascular disease was responsible for most late deaths.

Adult↗
PubMed1985

Neoplasia in immunosuppressed renal transplant patients: a 20-year experience.

This review examines a 20-year experience in renal transplantation at our center to determine the effects of immunosuppression on the subsequent development of malignancies. Twenty patients had 21 malignancies from primary sites other than skin, yielding an incidence of 2.5%. There were 0.65 malignancies for each 100 cumulative patient years of immunosuppression. Suppression of the host immune response is associated with an increased incidence of malignancies.

Adolescent↗
PubMed1983

Bilateral nephrectomy concomitantly with renal transplantation.

During a 2-year interval 206 patients underwent renal transplantation at a single center, 38 of whom underwent bilateral nephrectomy and other adjuvant operations as part of the transplant procedure. The indications for this type of procedure were reviewed, with special emphasis on the control of hypertension. The morbidity and mortality (16 per cent) in this group were compared in detail to those in patients not undergoing a concomitant adjuvant operation. The results with regard to renal function were similar to the group as a whole and the indications for appropriate patient selection are discussed.

Adolescent↗
PubMed1983

Invasive aspergillosis in renal transplant recipients: correlation with corticosteroid therapy.

During a 31-month period in 1979-1981, nine patients at a renal transplant center in Tennessee developed invasive infections with Aspergillus species. Despite an extensive search, no common environmental source of contamination was found. A matched case-control study of host risk factors showed that leukopenia, prior administration of antibiotics, and treatment with azathioprine and antilymphocyte serum were not significantly related to the development of aspergillosis. In contrast, the administration of high-dose corticosteroids posed a significant risk. An average daily dose of greater than or equal to 1.25 mg of prednisone/kg per day for the entire interval studied was the best predictor of subsequent invasive infection with Aspergillus.

Adrenal Cortex Hormones↗
PubMed1983

Factors influencing the outcome of kidney transplants.

This study is a multifactorial analysis of 389 transplants performed from June 1977 to December 1981. Analysis of the effects of transfusions antilymphocyte serum (ALS), histocompatibility testing, gender, and patient risk factors (presence of concomitant disease, greater than 50 years of age, etc.) was done. Two-hundred fifty-three patients received cadaver kidneys and 136 patients obtained kidneys from a relative. Two-hundred eighty-three (73%) patients received blood transfusions prior to transplantation. Our data showed that recipients receiving transfusions prior to transplantation had a significantly higher graft survival than those who were not transfused in both cadaveric and related graft recipients. Two-hundred twenty-one (56%) patients received ALS following the transplant. This group had a 15% higher graft survival than a comparable group. Analysis of histocompatibility testing data shows approximately 5% higher functional graft survival between each match grade. Surprisingly, female patients receiving kidneys from living related donors had a 16% higher graft survival than male patients. In cadaver recipients female patients had a 10% higher patient survival as compared to male patients. The risk factor status of recipients affected not only graft survival but patient survival, which probably is due to the consequences of immunotherapy. The authors' conclusion is that the above mentioned factors may be additive in nature. Further, multivariable analysis is necessary in order to correctly transplant data.

Antilymphocyte Serum↗
PubMed1983

Renal transplant arterial stenosis: percutaneous transluminal angioplasty.

Seven hypertensive patients underwent percutaneous transluminal angioplasty for relief of arterial stenosis complicating renal allotransplantation. Five had end-to-side anastomosis of the donor renal artery to the recipient external iliac artery, and two had end-to-end anastomosis of the donor renal artery to the recipient internal iliac artery. Each patient had developed hypertension (blood pressure greater than 145/95 mm Hg), elevated peripheral venous plasma renin, and six demonstrated decrease in renal function as detected by an increase in serum creatinine at least 2 months after transplantation and without evidence of rejection. Angioplasty was technically successful without significant complications and blood pressure and biochemical abnormalities were improved or stabilized in all seven patients.

Adolescent↗