Immediate retransplantation for pancreas allograft thrombosis.

Early pancreas allograft failure most commonly results from thrombosis and requires immediate allograft pancreatectomy. Optimal timing for retransplantation remains undefined. Immediate retransplantation facilitates reuse of the same anatomic site before extensive adhesions have formed. Some studies suggest that early retransplantation is associated with a higher incidence of graft loss. This study is a retrospective review of immediate pancreas retransplants performed at a single center. All cases of pancreas allograft loss within 2 weeks were examined. Of 228 pancreas transplants, 12 grafts were lost within 2 weeks of surgery. Eleven of these underwent allograft pancreatectomy for thrombosis. One suffered anoxic brain injury and was not a retransplantation candidate, one was retransplanted at 3.5 months and nine patients underwent retransplantation 1-16 days following the original transplant. Of the nine early retransplants, one pancreas was lost to heparin-induced thrombocytopenia, one recipient died with function at 2.9 years and the other grafts continue to function at 76-1137 days (mean 572 days). One-year graft survival for early retransplantation was 89% compared to 91% for all pancreas transplants at our center. Immediate retransplantation following pancreatic graft thrombosis restores durable allograft function with outcomes comparable to first-time pancreas transplantation.

Clustering of parasites within cages on Scottish and Norwegian salmon farms: alternative sampling strategies illustrated using simulation.

Within the literature, most discussion of sampling protocols for monitoring aquatic parasites is based on the assumptions of simple random sampling. Recent research has shown that in monitoring parasite abundance on fish farms composed of discrete cages, care must be taken to properly account for the clustering which naturally occurs. This paper illustrates the effect of clustering in the context of monitoring ectoparasitic sea lice Lepeophtheirus salmonis and Caligus elongatus in salmon farms. The degree of clustering of sea lice infections in fish within cages is measured using the intraclass correlation coefficient (ICC). A wide range of ICC values from sites in Scotland and Norway were estimated for the chalimus and mobile stages of L. salmonis, and for C. elongatus mobiles. The analyses indicate that significant clustering of lice infections within cages occurs across lice species and stages on both Scottish and Norwegian farms. A Monte-Carlo simulation using two sets of data from Scottish farms with ICC values for adult L. salmonis of 0.35 [0.08-0.73, 95% CI] and for adult C. elongatus of 0.39 [0.16-0.69, 95% CI] were used to illustrate the implications of clustering. The protocols simulated reflect those typically used across a range of countries and production environments in which salmon are currently reared. The findings demonstrate that the "few fish from many cages" approach results in a marked improvement in precision when sampling aquatic one-host parasites in cage-based production systems.

Extended Low-Dose Valganciclovir Is Effective Prophylaxis Against Cytomegalovirus in High-Risk Kidney Transplant Recipients With Near-Complete Eradication of Late-Onset Disease.

BACKGROUND: Cytomegalovirus (CMV)-seronegative kidney transplant (KTx) recipients of organs from CMV-seropositive donors (D+/R-) are at increased risk for CMV infection. Despite valganciclovir (VGCV) prophylaxis (900 mg daily for 200 days), late-onset CMV (LO-CMV) occurs at excessive rates. VGCV-associated cost and toxicities remain problematic. METHODS: We retrospectively evaluated 50 D+/R- adult KTx recipients from August 2008 to August 2014 who received low-dose VGCV (450 mg daily) prophylaxis for an extended duration. The primary outcome was occurrence of CMV disease. RESULTS: All patients received depletion induction and underwent ABO-compatible KTx. Mean prophylaxis and follow-up durations were 22.8 and 40.7 months, respectively. Eight patients developed CMV: 5 breakthrough cases (1 case of colitis [2%] and 4 cases of infection [8%]) and 3 cases of LO-CMV (1 syndrome [2.9%] and 2 cases of infection [5.7%]). On logistic regression, longer duration of VGCV prophylaxis was protective against CMV infection or disease (P = .044; odds ratio, 1.12 [95% confidence interval, 1.03-1.29]). None of 19 recipients with prophylaxis for ≥12 months developed LO-CMV compared with 3 of 16 recipients with prophylaxis for <12 months (18.8%) (P = .086). Four patients had recurrence of CMV, and 1 patient developed resistance. CMV was not responsible for graft or patient loss and did not affect survival. CONCLUSIONS: Low-dose VGCV is an effective prophylaxis for D+/R- KTx recipients despite depleting induction. Longer prophylaxis is more protective, and receiving VGCV for ≥12 months nearly eradicated LO-CMV without increasing antiviral resistance.

Using fast sequential asymmetric fanbeam transmission CT for attenuation correction of cardiac SPECT imaging.

UNLABELLED: The objective of this study was to determine the feasibility of using a fast (short-duration) transmission computed tomogram (TCT), acquired immediately before or after the emission CT, to correct for photon attenuation in cardiac SPECT. METHODS: The asymmetric fanbeam geometry with a 99mTc line source was used to acquire TCTs after conventional cardiac emission CT imaging on a triple-head SPECT system. The TCTs were reconstructed to generate patient-specific attenuation maps, which were used with an iterative maximum likelihood algorithm to reconstruct attenuation-corrected cardiac SPECT studies. The results of attenuation correction based on TCTs as short as 1 min were compared with long-duration transmission imaging for a phantom and several human studies. RESULTS: Attenuation correction based on asymmetric fanbeam TCT significantly improves the uniformity of images of a uniform tracer distribution in a cardiac-thorax phantom configured to simulate a large patient. By using a high-activity line source and a rapid camera rotation, a suitable attenuation map for this phantom can be obtained from a 4-min TCT. A similar result is obtained for patients with thorax widths of <40 cm. CONCLUSION: A sequential imaging protocol for acquiring a fast TCT can be used for attenuation correction of cardiac SPECT imaging. The sequential TCT can be acquired without significantly extending the duration of the imaging study. This method provides a way to perform attenuation correction on existing triple-head SPECT systems without extensively modifying the system.

Do angiogenesis and growth factor expression predict prognosis of esophageal cancer?

A retrospective study of surgically resectable esophageal cancers was undertaken to determine the relationship between angiogenesis score and growth factor expression with tumor size, histology, degree of differentiation, depth of invasion, nodal disease, and the presence of Barrett's esophagus. The office and hospital charts of 27 patients who had esophageal resection for carcinoma between 1990 and 1995 at Rush-Presbyterian-St. Luke's Medical Center were reviewed. Data collection included patient demographics, survival, tumor size, histology, differentiation, depth of invasion, nodal metastases, and the presence of Barrett's esophagus. The pathology specimens were immunostained for von Willebrand factor (factor VIII-related antigen). Immunostaining was also performed for vascular endothelial growth factor and transforming growth factor alpha. Twenty normal esophageal specimens served as controls. Angiogenesis score was determined by counting vessels under conventional light microscopy at x200 magnification, and growth factor expression was graded on a scale of 1 to 4. Cancers had higher angiogenesis and growth factor expression than controls (P = 0.01). Patient age, tumor size, histology, differentiation, depth of invasion, and Barrett's esophagus did not correlate with angiogenesis score or tumor growth factor expression. Lymph node status did correlate with both angiogenesis score and growth factor expression (P < or = 0.02). We conclude that high angiogenesis score and growth factor expression correlate with the presence of lymph node metastases. This may help select patients for preoperative radiation and chemotherapy or determine the extent of surgery performed for esophageal carcinoma.

Hematopoietic cytokine-mediated FDG uptake simulates the appearance of diffuse metastatic disease on whole-body PET imaging.

FDG-PET is increasingly being used to assess malignant tumors. However, leukocyte colony-stimulating factors (CSFs), which promote the expansion of hematopoietic bone marrow, have also been demonstrated to cause increased bone-marrow FDG uptake. Three hundred FDG-PET studies conducted over a 1-year period were reviewed for diffuse bone-marrow uptake. Elevated bone-marrow uptake on PET was correlated with pathological findings and courses of granulocyte-CSF (G-CSF) therapy. These results demonstrate that G-CSF mediated FDG uptake in bone marrow is often indistinguishable from that caused by disseminated metastatic disease. However, the bone-marrow response to G-CSF decreases rapidly following the last CSF administration. Therefore, FDG-PET in patients receiving G-CSF should be delayed, when possible, until 5 days after the end of G-CSF therapy.

Pelvic metastases from pancreatic carcinoma: a pattern observed on bone scan.

Metastases to the bony pelvis is an unusual pattern of the spread of primary pancreatic tumors. The authors report the presence of metastatic disease in the bony pelvis observed on bone scans in several patients who had been treated recently for pancreatic carcinoma. When bone scans that show metastatic disease in the pelvis are evaluated in patients with unknown primaries, the diagnosis of pancreatic carcinoma should be considered.

Normal thymic uptake of 2-deoxy-2[F-18]fluoro-D-glucose.

Whole-body 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) positron emission tomography (PET) of a 54-year-old woman with a history of recurrent thyroid follicular cancer and an elevated thyroglobulin level showed significant FDG uptake in the thyroid bed and anterior mediastinum. A previous scan after high-dose I-131 therapy also showed iodine uptake in these regions. Because of a lack of response to iodine therapy, the patient had surgery. Recurrent thyroid cancer was found in the neck, but the mediastinal lesion was shown to consist of normal thymus tissue. In repeated examinations performed after surgery, there was no uptake of FDG or I-131 in the anterior mediastinum. Previous treatment with a high dose of radioiodine may have contributed to visualization of a normal adult thymus with FDG PET.

Mechanical, histologic, and biochemical effects of canine rectal formalin instillation.

UNLABELLED: Instillation of 4 percent formalin effectively treats radiation hemorrhagic proctitis; however, little is known regarding its side effects. PURPOSE: The study contained herein was undertaken to determine rectal compliance and collagen content, mucosal and vascular histologic changes, and kinetics of formalin absorption following instillation. METHODS: Fifteen mongrel dogs (50-60 pounds) were randomized into five experimental groups according to time elapsed from formalin treatment: control, acute, one week, two weeks, and four weeks. Formalin was instilled in 30-ml aliquots to a total volume of 400 ml. Rectal compliance (closed manometry system) was assessed pre-formalin and post-formalin at the designated time interval. Serum formalin metabolites were determined at time 0, 0.5, 1, and 3 hours. A segment of rectal wall was analyzed for collagen content, mucosal injury, and blood vessel density. RESULTS: Serum formalin levels peaked within 30 minutes, returning to normal by 3 hours. With the exception of one dog, toxic levels were not reached at any time during the study. No dogs experienced sepsis, fever, or altered gastrointestinal function. Acute and one-week dogs showed mild diffuse proctitis and mucosal slough, which healed within two weeks. Rectal compliance and collagen content were unchanged. Mucosal blood vessels decreased in number early (P = 0.03). CONCLUSIONS: Instillation of 4 percent formalin in sequential aliquots of a small volume that is kept in contact for a short period of time is safe. Serum formalin levels generally do not reach toxic levels, and the slight elevation in formalin concentration that was seen returns to normal within three hours. Formalin-induced proctitis heals within two weeks, and no long-term changes in rectal compliance or collagen content were seen.