Correlation between cystoscopic biopsy results and hypoamylasuria in bladder-drained pancreas transplants

BACKGROUND

Urinary amylase (UA) remains the most common biochemical parameter to detect rejection in bladder-drained pancreas allografts. With the development of the cystoscopic transduodenal pancreas transplant biopsy technique, tissue samples of the pancreas graft are now frequently obtained. A definitive correlative analysis between UA activity and biopsy results has not been done in the three different pancreas transplant categories (simultaneous pancreas-kidney, pancreas transplant alone, and pancreas after kidney).

METHODS

We studied 66 pancreaticoduodenal biopsy specimens obtained for hypoamylasuria. Rejection was defined as a greater than 25% decrease from stable posttransplantation baseline on two consecutive measurements at least 12 hours apart. To perform biopsies we used our newly developed 14- and 16-gauge core-cut needles (50 cm long). Biopsy specimens were considered positive if either pancreatic or duodenal rejection was found. To assess the quality of UA activity we studied 13 biopsy specimens from patients with stable UA levels; these 13 specimens were negative for rejection.

RESULTS

Acute rejection was diagnosed in 36 biopsy specimens (55%). The mean decrease in UA levels was 67% +/- 8% (range, 28% to 99%) for the positive biopsy results, and 57% +/- 16% (range, 22% to 92%) for the negative biopsy results (p = 0.147). Within 1 month, UA levels returned to baseline in 19% of our patients with positive biopsy results versus 97% with negative results; postbiopsy 1-year graft survival was 64% versus 97% (p < or = 0.05). In assessing the test quality of our biopsy specimens (including 13 obtained for reasons other than hypoamylasuria), we found a sensitivity of 100% (stable UA levels mean no rejection) and a specificity of 30%. The predictive value of a positive test was 53%; of a negative test it was 100%. By performing biopsies we avoided antirejection treatment in 47% of the patients studied. We found no biopsy-related complications.

CONCLUSIONS

Stable UA levels reliably rule out rejection; a decrease is a marker for acute rejection but is unspecific. Performing biopsy is currently the only way to reliably diagnose rejection in solitary pancreas recipients (pancreas transplant alone and pancreas after kidney) and in simultaneous pancreas-kidney recipients with isolated hypoamylasuria. The procedure is safe and should always be attempted to avoid unnecessary rejection treatment.

Laparoscopic drainage of lymphoceles after kidney transplantation: indications and limitations

BACKGROUND

Symptomatic lymphoceles are not uncommon after kidney transplantations. Surgical marsupialization with internal drainage is the treatment of choice. However, laparoscopic drainage is reportedly as effective, with only minimal trauma.

METHODS

We attempted 14 laparoscopic lymphocele drainages during a 3-year period and studied the indications and limitations, using intraoperative ultrasonography in all cases.

RESULTS

Laparoscopic drainage was successful in only 9 (64%) of 14 patients. A conversion to open laparotomy was necessary in five patients; their lymphoceles were lateral and either posterior or inferior to the kidney. Two patients with initially successful laparoscopic drainage required conversion to open laparotomy 21 and 83 days later; their lymphoceles were inferior to the kidney. Laparoscopic drainage shortened the median hospital stay by 4 days versus open surgical drainage and by 7 days versus conversion. Hospital costs for laparoscopic drainage averaged $7400 less versus open drainage and $10,300 less versus conversion.

CONCLUSIONS

In patients with symptomatic lymphoceles medial and either superior or anterior to the kidney, laparoscopic drainage under intraoperative ultrasonographic guidance is easy, safe, and effective. It decreases hospitalization, convalescence, and costs. In patients with symptomatic lymphoceles lateral and either posterior or inferior to the kidney, laparoscopic drainage may fail because of anatomic inaccessibility and technical impracticability.

A prospective study of FK506 versus CsA and pig ATG in a porcine model of small bowel transplantation

Rejection remains a major barrier to successful bowel transplantation, and immunosuppressive protocols are far from standardized. In 88 nonrelated outbred pigs, we compared the effects of two immunosuppressive regimens--one with FK506, the other with cyclosporine (CsA) and pig antithymocyte globulin (ATG)--on incidence and severity of rejection in the early, critical posttransplant period. Group A (n = 14) was nonimmunosuppressed (controls). Group B (n = 17) received pig ATG (10 mg/kg/day x 10 days), CsA (3 mg/kg/day), prednisolone (2 mg/kg/day), and azathioprine (2.5 mg/kg/day); prednisolone and azathioprine were each reduced by 50% at 8 and 15 days posttransplant. Trough CsA whole-blood concentrations were > or = 400 ng/ml for the first 7 days, > or = 200 ng/ml thereafter. Group C (n = 13) received FK506 (0.2 mg/kg/day) and prednisolone (2 mg/kg/day); prednisolone was reduced by 50% at 8 and 15 days. FK506 whole-blood concentrations were > or = 20 ng/ml. All immunosuppression in groups B and C was given intravenously. We performed orthotopic small bowel transplants with systemic venous drainage. Recipient bowel was resected distal to the second portion of the duodenum and proximal to the rectum at transplant; bowel continuity was restored by duodenojejunostomy; ileostomy was created distally to allow access for daily biopsies. We graded interstitial and vascular rejection separately, according to a scoring system (no, mild, moderate, and severe rejection). Rejection-free graft survivals at 7, 14, and 21 days posttransplant were 38%, 19%, and 0% in group A; 93%, 93%, and 62% in group B; and 100%, 91%, and 82% in group C (P < 0.001). Comparing rejection in the immunosuppressed groups, group C (FK506) had a stronger tendency toward rejection than group B (CsA-ATG); significant differences between groups B and C were, however, noted only on individual days posttransplant, not over time. The death rate due to irreversible rejection was not significantly different in groups B and C (P = 0.8), but was significantly better in both of these immunosuppressed groups than in group A (P < 0.001). Pig survival was significantly longer in group C than in B (P = 0.001) due to a lower infection rate in group C. Posttransplant serum interleukin 2 and 7 levels did not correlate with rejection grades. Graft-versus-host reaction was noted only in the skin in 29% of group A, 73% of group B, and 77% of group C pigs; liver and native bowel were not involved.(ABSTRACT TRUNCATED AT 400 WORDS)

Recipient risk factors have an impact on technical failure and patient and graft survival rates in bladder-drained pancreas transplants

Recipient selection criteria for pancreas (Px) transplantation differ among centers, based on perceived recipient risk factors, and their validity has not been determined. At the University of Minnesota we have been very liberal in accepting patients for Tx, some of whom have risk factors cited as exclusion criteria by other centers, giving us the opportunity to determine, retrospectively, the impact of their presence on outcome. Between July 1986 and March 1993, we performed 319 bladder-drained cadaver Px Txs at the University of Minnesota, 166 simultaneous with a kidney (SPK), 68 after a kidney (PAK), and 85 alone (PTA). To determine which putative "risk factors" influence patient and graft survival, we used uni- and multivariate (Cox regression) analyses to assess the impact of recipient category, duration of diabetes, and age at onset and at Tx; presence of pre-Tx cardiac (CD) disease (myocardial infarction, bypass, angioplasty), peripheral vascular disease (PVD) (stroke, bypass, angioplasty, amputation); blindness, hypertension, and excess weight; and of Px re-Txs. The incidences of all risk factors except re-Tx were significantly higher in SPK than PTA recipients. Px re-Txs comprised 40% of PAK, 26% of PTA, and 10% of SPK cases (P < 0.0001). Duration of diabetes correlated (P < or = 0.01) with all risk factors but one (hypertension). Recipient age correlated (P < or = 0.01) with CD, blindness, duration of diabetes, and age at onset of diabetes; CD risk factors correlated (P < 0.015) with hypertension and PVD. Recipient age (> or = 45) influenced the technical failure rate only in SPK recipients, with a relative risk (RR) of 2.13 (P = 0.08). Recipient age influenced Px graft and patient survival rates in both SPK and PAK recipients; for those > or = 45, the RR of graft loss was 1.73 and 1.76, respectively (P < or = 0.25), and the RR for ultimately dying was 3.07 in PAK (P = 0.02) and 5.86 in SPK (P = 0.17) recipients. SPK recipients with CD factors were at higher risk to ultimately die (RR = 3.78, P = 0.009), independent of age. Px re-Txs were not at higher risk to fail in PTA, but were in PAK recipients (RR = 1.86, P = 0.09); the risk for technical failure was higher for re-Txs only in SPK recipients (RR = 2.11, P = 0.24). Blindness, hypertension, PVD, and duration of diabetes did not negatively influence patient and graft outcome in any recipient category.(ABSTRACT TRUNCATED AT 400 WORDS)