Graft-dependent renal hyperparathyroidism despite successful kidney transplantation.

INTRODUCTION: Only a few reports can be found on the recurrence or persistence of hyperparathyroidism after total parathyroidectomy and autotransplantation (PTX + AT) following kidney transplantation (KTX). The objective of the present study was to assess the frequency and pathophysiological mechanisms responsible for the development of graft-dependent renal hyperparathyroidism (rHPT) after KTX. PATIENTS AND METHODS: Between 1986 and 2006, 69 patients underwent surgery for rHPT after KTX at our institution. Patients with reoperations at the parathyroid autograft (AT) were identified. Kidney graft function (KGF) was assessed by the glomerular filtration rate (GFR). Representative parts of the parathyroid gland chosen for autotransplantation during the initial parathyroidectomy and of the excised AT at reoperation were reanalyzed according to the morphologic pattern and the proliferative index. RESULTS: Eight of the 69 patients underwent reoperation of the AT. All patients had undergone initial PTX + AT before KTX. The GFR before parathyroid reoperation was 66.6 +/- 9.6 ml/min per1.73 m(2) (mean +/- SEM). Histopathological re-examination revealed nodular hyperplasia in the parathyroid tissue for autotransplantation and in the excised parathyroid autografts. The Ki67 index was increased in the glands chosen for autotransplantation prior to KTX, but was overall low in the excised autografts. DISCUSSION: Although not reported in the literature to date, tertiary hyperparathyroidism (tHPT) may arise from parathyroid autografts even in patients with a good KGF. In these cases, graft-dependent tHPT represents the inability of autonomous, nodular parathyroid tissue to regress despite the recovery of renal function. Non-nodular tissue should be selected for parathyroid autotransplantation to decrease the incidence of graft-dependent recurrent rHPT.

Endoscopic full-thickness resection of the stomach: an experimental approach.

BACKGROUND: Endoluminal endoscopic resections of the gastrointestinal (GI) tract have had increasing significance in recent years. Except for the extraperitoneal part of the rectum, endoscopic resections are restricted to the mucosal and submucosal layer to preserve the integrity of the GI tract wall. METHODS: The SurgAssist is the first flexible stapling device consisting of a 2,000-mm-long flexible shaft and a stapling magazine that can be positioned intraluminally and used with a remote control. To prove the principle, we investigated the endoluminal application of an endoscopically assisted and intraluminally visualized full-thickness resection of the gastric wall in a pilot study of three pigs and a series of three human exenterates. RESULTS: Full-thickness resection of the gastric wall in pigs can be performed with the SurgAssist flexible stapling device from an endoluminal access. However, due to the small lumen of the esophagus, the simultaneous transesophageal introduction of the stapler shaft and gastroscope is not possible in pigs. The same procedure in three human exenterates showed that the simultaneous introduction of the flexible stapler and a standard gastroscope could be achieved without damaging the esophageal wall. Full-thickness resections of up to 4 x 4 cm were carried out with the use of two or three stapler magazines. The resulting sutures were found to be airtight upon endoscopic inflation of the stomach. CONCLUSION: The clinical use of the SurgAssist intraluminal stapling device for endoscopic full-thickness resection of the gastric wall seems applicable for lesions in suitable locations of the stomach. Gastrointestinal stroma tumors and T1 tumors of the lower gastric corpus and antrum region are possible indications.

Endoscopic treatment of postoperative colorectal anastomotic strictures.

BACKGROUND: The postoperative development of benign colorectal anastomotic stricture remains a frequent and unsolved problem. METHODS: From 1996 until 2002, we analyzed 94 consecutive patients with postoperative colorectal anastomotic stenosis who were treated endoscopically. RESULTS: Sixty-eight patients were initially resected for malignant disease, and 26 patients for benign conditions. Most frequently, hydrostatic balloon dilatation was performed; in selected cases, it was combined with a laser or argon plasma coagulation (APC) incision, or a laser incision only. Dilatation was successful in 59% of patients resected for cancer and 88% resected for a benign condition. Complications developed in 17 patients (benign restenosis, perforation, abscess); they were significantly more frequent after initial cancer resection than after resection for a benign condition ( p < 0.05). CONCLUSION: High success and low complication rates make endoscopic dilatation the treatment of choice to avoid high-risk reoperations in patients with benign anastomotic stricture. The presence of stapler anastomosis, postoperative leakage, and/or radiotherapy does not significantly impede successful endoscopic dilatation.