Marco Castaneda

Peptic ulcer disease following transplantation: The role of cimetidine

Of 253 consecutive renal transplants performed in 209 patients between January 1971 and December 1980, symptomatic gastroduodenal ulcerations developed in 22 (8.7 percent). Time of presentation ranged from 5 days to 9 years (mean 225 days) following transplantation with 16 of these patients presenting within the first 3 months. Nine (Group I) patients were diagnosed before the administration of H2 antagonist cimetidine. Mode of presentation in this group was upper gastrointestinal bleeding in each instance. Thirteen patients (Group II) were diagnosed after the clinical use of cimetidine was established. The mode of presentation in this group was bleeding in 11 patients and abdominal pain in 2 patients. In Group I, one patient died from liver failure and an ulcer was not contributory. The remaining eight patients were treated with antacids and blood transfusions (mean 12.7 units). Five patients in this group demonstrated ulcer healing, whereas three patients (37.5 percent) required emergency operations with two postoperative deaths. In Group II, one patient died from hemorrhagic shock before therapy could be instituted. In the other 12 patients treatment consisted of antacids, cimetidine, and blood transfusions (mean 6.8 units). Ten patients had relief of symptoms, whereas two patients (16.7 percent) required emergency operations with no deaths. During cimetidine therapy, two patients had rejection episodes that were reversible, and the remaining patients had no significant alterations in renal function. To conclude, cimetidine is a safe and effective adjunct in the treatment of peptic ulceration in renal transplant recipients.

An experimental evaluation of nucleotide enhancement techniques for kidney transplantation

The effect of various nucleotide-enhancing agents on renal function and intracellular nucleotide levels was evaluated in a canine autotransplant model. Thirty-five dogs (18-28 kg) underwent left nephrectomy and 30 min of warm ischemia followed by Collins C-4 flush and 24 hr of cold-storage preservation. Heterotopic autotransplantation and immediate contralateral nephrectomy was then performed. Seven equal groups were evaluated: group A--controls, group B--adenosine pretreatment (1.0 g), group C--dipyridamole pretreatment (10 mg), group D--adenosine (1.0 g), and dipyridamole (10 mg) pretreatment, group E--adenosine (200 mg) and EHNA (2.5 mg/kg) pretreatment, group F--adenosine (200 mg) and EHNA (2.5 mg/kg) in the Collins C-4 flush, and group G--adenosine (200 mg) and EHNA (2.5 mg/kg) at the time of autotransplantation. All kidneys underwent cortical biopsies at the end of preservation and 1 hr after restoration of blood flow for determinations of AMP, ADP, and ATP. In the pretreatment groups (groups B through E) there was 60% graft survival whereas the controls (group A) and the groups treated after ischemia (groups F and G) had 0, 0, and 20% graft survival, respectively. In groups B and E, ATP levels were greater than controls after preservation and 1 hr after restoration of blood flow. Group C AMP and ADP levels and group D energy charge were greater than controls in the post-transplantation biopsies. Administration of adenosine and EHNA after ischemia was not associated with increased intracellular nucleotide levels. One hour post-transplantation biopsies demonstrated greater ability to regenerate cortical nucleotides in the surviving animals but no absolute value could be identified as a predictor of viability. In conclusion, pretreatment with adenosine, dipyridamole, and EHNA alone and in combination is beneficial in ischemically injured kidneys undergoing cold-storage preservation.

In Search of an in Vitro Index of Viability during Pancreatic Preservation

To determine an index of viability during pancreatic preservation, 15 dogs underwent segmental pancreatic autografting after 24 hr of pulsatile perfusion. These animals were divided into Group A (6) and Group B (9) on the basis of post-transplant normoglycemia or hyperglycemia. In each experiment, sequential perfusate amylase and arterial and venous blood gases were analyzed during preservation. In addition, sequential pancreatic tissue slices were obtained to determine in vitro insulin release. A comparison of perfusion parameters demonstrated no significant differences in pancreas weight (41 +/- 2.9 vs 38.3 +/- 1.5 mg), perfusate flow (0.24 +/- 0.2 vs 0.20 +/- 0.06 ml/min/g), diastolic (24.3 +/- 2.3 vs 26.9 +/- 1.6 mm Hg) or mean pressure (27.4 +/- 1.9 vs 30.1 +/- 1.5 mm Hg). Perfusate amylase levels (u/100 ml) and percentage change from baseline are as follows: (Table: see text). Perfusate amylase was significantly greater at 21 hr in Group A (P less than 0.005). In addition, a significantly greater rate of amylase release was evident in Group A at 1 hr (P less than 0.02), 3 hr (P less than 0.02), and 21 hr (P less than 0.01). Group B pancreata demonstrated significantly increased oxygen extraction at 1 hr (A-V O2 difference: Group A = -33, Group B = -68; P less than 0.05). In vitro insulin release of tissue slices obtained pre-harvest, post-flush, post-preservation, and 15 min post-transplantation was not significantly different in the two groups. In conclusion, sequential perfusate amylase and blood gas determinations may be useful in predicting pancreatic transplant function.

General surgical procedures in renal allograft recipients

Since elective and emergent nontransplant-related surgical procedures are frequently necessary in renal allograft recipients, it becomes essential to determine the incidence and outcome of these operations in this population. For this reason, a retrospective analysis of 273 consecutive renal transplants performed in 254 patients between January 1978 and November 1985 was accomplished. During this interval, 139 patients underwent 162 nontransplant-related surgical procedures. In the 44 patients who underwent 55 emergent or semiemergent procedures, 8 patients (18 percent) died in the postoperative period. All deaths occurred in patients who underwent major abdominal or thoracic procedures for perforated viscera, gastrointestinal bleeding, or empyema and lung abscess, and all deaths were secondary to sepsis and multiple organ failure. In the survivors of emergent procedures, the mean preoperative and discharge serum creatinine levels were 2.87 mg/dl and 2.82 mg/dl, respectively. In the 95 patients who underwent 107 elective procedures, most of which were performed under general anesthesia, the operative mortality was 4.2 percent. In patients with stable renal allograft function at the time of operation, mean serum creatinine levels preoperatively and at the time of discharge were not significantly different (1.74 mg/dl versus 1.64 mg/dl). In conclusion, emergent operative procedures for intraabdominal or thoracic catastrophes are associated with a high mortality rate in renal allograft recipients. On the other hand, elective surgical procedures can be undertaken with an acceptable mortality rate and no adverse affects on graft function. Of utmost importance in these patients is the close monitoring of the immunosuppressive regimen and the early detection and treatment of potential septic complications.