Renal Allograft Rupture: A Clinicopathologic Review

Transplantation Proceedings Volume 32, Issue 8, December 2000, Pages 2597-2598 -------------------------------------------------------------------------------- doi:10.1016/S0041-1345(00)01801-7 | How to Cite or Link Using DOI Copyright © 2000 Elsevier Science Inc. All rights reserved. Cited By in Scopus (4) Permissions & Reprints Renal allograft rupture: a clinicopathologic review M Ramosa, , L Martinsa, L Diasa, A.C Henriquesa, J Soaresa, J Queirósa and A.M Sarmentoa aDepartments of Urology and Nefrology, Hospital Geral de Santo António, Oporto, Portugal Available online 19 December 2000. Article Outline Patients and methods Results Discussion References Renal allograft rupture (RAR) is a rare but very serious complication of renal transplantation, requiring emergency surgery. The most common cause is acute allograft rejection, but other causes such as renal vein thrombosis (RVT), acute tubular necrosis (ATN), renal biopsy, and lymphatic obstruction have been reported.[1] and [2] We reviewed our experience with the aim of identifying RAR predisposing conditions. Patients and methods In a consecutive series of 934 renal transplants performed between July 1983 and September 1999, 11 patients (1.2%) had RAR. In these cases we studied donor and recipient characteristics, preservation conditions, clinical signs and symptoms, treatment, and pathology findings. This group of patients was then compared with their paired cohort. Data analysis was computer-based. In the statistical analysis t test and Fisher’s exact test were used. Results All 11 kidneys that suffered RAR were from cadaver donors, nine male and two female. The mean age was 29.5 years with good terminal serum creatinine (mean 1.1 mg/dL). All organs were stored in Eurocollins solution and the mean cold ischemia time was 21 hours and 25 minutes (range, 10 hours to 29 hours and 20 minutes). Excluding one black patient, all recipients were Caucasian. Eight were female and 3 were male, with a mean age of 33.8 years. The mean HLA match was 1.7, and the mean peak panel reactive antibody (PRA) was 22% (range 0 to 93%) and current was 15% (range 0 to 67%). All patients had cyclosporine treatment, eight had delayed graft function requiring dialysis, and three underwent renal allograft biopsy. In two patients rupture occurred in the second allograft; the others were first transplants. The day of RAR was a mean of 5.3 (range 2 to 13). All patients had new onset of severe allograft pain, eight had a drop in daily hematocrit, and six had hypotension. The four patients with more precocious ruptures had sudden onset of bleeding through the drainage tube. Transplant nephrectomy was performed in 10 patients, and surgical conservative treatment with fibrin glue and collagen foam was performed in one. All patients survived RAR. Three had a second transplant and currently have functioning allografts. Pathology examination revealed RVT in three patients and some degree of rejection in the remaining eight. One patient had a rupture on the second day because of hyperacute rejection, and three had severe acute cellular rejection, but in four patients the dominant figure was ATN with minimal rejection. Excluding the patient with hyperacute rejection, the day of rupture was later for those with severe acute rejection, a mean of 9.6 days (range 6 to 13). In those with ATN, the day of RAR was a mean of 4.5 (range 3 to 6) and the patients with RVT had ruptures even sooner, on mean third day (range 2 to 4). Variables associated with RAR were: sex mismatch (P = .004), current PRA (P = .012), and a need for dialysis (P = .042). Age of the recipient, transplant number, cold ischemia time, total HLA match, and peak PRA were not associated with RAR. Discussion Higher current PRA and a need for dialysis are variables associated with rejection and ATN. Therefore they are expected to be related to rupture. The well-documented conditions that are associated with ATN and rejection3 must be the same, which in extreme conditions predispose to RAR. We find no explanation for the statistically significant association of sex mismatch and RAR, other than random error. Acute allograft rejection is the most frequent cause of graft rupture in the literature (60 to 80%),3 but ATN has received little note. In our series, ATN was responsible for 36% of the ruptures, as much as severe acute rejection. ATN alone can cause RAR,4 because of interstitial edema and rise in intrarenal pressure. But when associated with rejection, it seems that these two conditions can act synergistically to cause allograft rupture. Our data suggests that rupture occurs later when caused by rejection, rather than when RVT is responsible. To our knowledge this finding had never been reported in world literature. Perhaps the timing of RVT is related to technical problems, such as twisting and kinking of the vein or intima tear, although the thrombogenic effect of cyclosporine can also have a role in this process.5 All these patients were on cyclosporine therapy, which may explain the small number of RAR caused by rejection alone and the significant number of patients that had RVT (27%). It appears that cyclosporine therapy is changing the etiology of the graft rupture.6 References 1 T. Grochowiecki, J. Szmidt and K. Madej et al., Transplantation Proc 28 (1996), p. 3461. View Record in Scopus | Cited By in Scopus (2) 2 R.S. Lord, D.J. Effeney and J.M. Hayes et al., Ann Surg 177 (1973), p. 268. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (4) 3 G.J. Azar, A. Zarifian and G.D. Frentz et al., Clin Transplantation 10 (1996), p. 635. View Record in Scopus | Cited By in Scopus (12) 4 Y.H. Chan, K.M. Wong and K.C. Lee et al., Am J Kidney Dis 34 (1999), p. 355. Abstract | Article | PDF (86 K) 5 R.M. Jones, J.A. Murie and A. Ting et al., Clin Transplant 2 (1988), p. 122. 6 A.J. Richardson, R.M. Higgins and A.J. Jaskowski et al., Br J Surg 77 (1990), p. 558. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (19

Evaluation of urinary cysteinyl leukotrienes as biomarkers of severity and putative therapeutic targets in COVID-19 patients

Background Cysteinyl leukotrienes (CysLT) are potent inflammation-promoting mediators, but remain scarcely explored in COVID-19. We evaluated urinary CysLT (U-CysLT) relationship with disease severity and their usefulness for prognostication in hospitalized COVID-19 patients. The impact on U-CysLT of veno-venous extracorporeal membrane oxygenation (VV-ECMO) and of comorbidities such as hypertension and obesity was also assessed. Methods Blood and spot urine were collected in severe (n = 26), critically ill (n = 17) and critically ill on VV-ECMO (n = 17) patients with COVID-19 at days 1-2 (admission), 3-4, 5-8 and weekly thereafter, and in controls (n = 23) at a single time point. U-CysLT were measured by ELISA. Routine markers, prognostic scores and outcomes were also evaluated. Results U-CysLT did not differ between groups at admission, but significantly increased along hospitalization only in critical groups, being markedly higher in VV-ECMO patients, especially in hypertensives. U-CysLT values during the first week were positively associated with ICU and total hospital length of stay in critical groups and showed acceptable area under curve (AUC) for prediction of 30-day mortality (AUC: 0.734, p = 0.001) among all patients. Conclusions U-CysLT increase during hospitalization in critical COVID-19 patients, especially in hypertensives on VV-ECMO. U-CysLT association with severe outcomes suggests their usefulness for prognostication and as therapeutic targets.This work was supported by a RESEARCH 4 COVID-19 grant (project 519, reference number: 613690173) from FCT-Fundacao para a Ciencia e a Tecnologia (special support for rapid implementation projects for innovative response solutions to COVID-9 pandemic). CS-P is a recipient of a Ph.D. fellowship from FCT and MedInUP (UI/BD/150816/2020). P-PT was supported by a research contract within the scope of the RIFF-HEART project funded by FEDER via COMPETE, Portugal 2020-Operational Programme for Competitiveness and Internationalization (POCI) (POCI-01-0145-FEDER-032188) and by FCT (PTDC/MEC-CAR/32188/2017). Open access funding provided by FCT|FCCN (b-on)

Muon Array with RPCs for Tagging Air showers (MARTA)

We discuss the concept of an array with Resistive Plate Chambers (RPC) for muon detection in ultra-high energy cosmic ray (UHECR) experiments. RPC have been used in particle physics experiments due to their fast timing properties and spatial resolution. The operation of a ground array detector poses challenging demands, as the RPC must operate remotely under extreme en- vironments, with limited power and minimal maintenance. In its baseline configuration, each MARTA unit includes one 1.5x1.2 m 2 RPC, with 64 pickup electrodes (pads). The DAQ sys- tem is based on an ASIC, allowing one to read out the high number of channels with low power consumption. Data are recorded using a dual technique: single particle counting with a simple threshold on the signal from each pad and charge integration for high occupancy. The RPC, DAQ, High Voltage and monitoring systems are enclosed in an aluminum-sealed case, providing a com- pact and robust unit suited for outdoor environments, which can be easily deployed and connected. The RPCs developed at LIP-Coimbra are able to operate using very low gas flux, which allows running them for few years with a small gas reservoir. Several full-scale units are already installed and taking data in several locations and with different configurations, proving the viability of the MARTA concept. By shielding the detector units with enough slant mass to absorb the electro- magnetic component in the air showers, a clean measurement of the muon content is allowed, a concept to be implemented in a next generation of UHECR experiments. The specificities of a MARTA unit are presented, which include particle counting with high efficiency, time resolu- tion and spatial segmentation. The potential of the MARTA concept for muon measurements in air showers is assessed, as well as tentative methods for calibration and cross-calibrations with existing detectors.Peer Reviewe

Combined Pancreas-Kidney Transplantation: A New Program in Portugal, Results From the First 12 Cases

Transplant Proc. 2003 May;35(3):1107-8. Combined pancreas-kidney transplantation: a new program in Portugal, results from the first 12 cases. Martins L, Henriques A, Dias L, Ventura A, Seca R, Almeida R, Dores J, Bacelar C, Oliveira F, Lhamas A, Amil M, Rua F, Coelho T, Esteves S, Ribeiro A, Pereira R, Sarmento A, Teixeira M, Pereira M. Transplantation Department, Hospital Santo António, 4050, Porto, Portugal. [email protected] PMID: 12947877 [PubMed - indexed for MEDLINE

A Herbivorous Mite Down-Regulates Plant Defence and Produces Web to Exclude Competitors

Herbivores may interact with each other through resource competition, but also through their impact on plant defence. We recently found that the spider mite Tetranychus evansi down-regulates plant defences in tomato plants, resulting in higher rates of oviposition and population growth on previously attacked than on unattacked leaves. The danger of such down-regulation is that attacked plants could become a more profitable resource for heterospecific competitors, such as the two-spotted spider mite Tetranychus urticae. Indeed, T. urticae had an almost 2-fold higher rate of oviposition on leaf discs on which T. evansi had fed previously. In contrast, induction of direct plant defences by T. urticae resulted in decreased oviposition by T. evansi. Hence, both herbivores affect each other through induced plant responses. However, when populations of T. evansi and T. urticae competed on the same plants, populations of the latter invariably went extinct, whereas T. evansi was not significantly affected by the presence of its competitor. This suggests that T. evansi can somehow prevent its competitor from benefiting from the down-regulated plant defence, perhaps by covering it with a profuse web. Indeed, we found that T. urticae had difficulties reaching the leaf surface to feed when the leaf was covered with web produced by T. evansi. Furthermore, T. evansi produced more web when exposed to damage or other cues associated with T. urticae. We suggest that the silken web produced by T. evansi serves to prevent competitors from profiting from down-regulated plant defences

Spider mite web mediates anti-predator behaviour

Herbivores suffer significant mortality from predation and are therefore subject to natural selection on traits promoting predator avoidance and resistance. They can employ an array of strategies to reduce predation, for example through changes in behaviour, morphology and life history. So far, the anti-predator response studied most intensively in spider mites has been the avoidance of patches with high predation risk. Less attention has been given to the dense web produced by spider mites, which is a complex structure of silken threads that is thought to hinder predators. Here, we investigate the effects of the web produced by the red spider mite, Tetranychus evansi Baker & Pritchard, on its interactions with the predatory mite, Phytoseiulus longipes Evans. We tested whether female spider mites recognize predator cues and whether these can induce the spider mites to produce denser web. We found that the prey did not produce denser web in response to such cues, but laid more eggs suspended in the web, away from the leaf surface. These suspended eggs suffered less from predation by P. longipes than eggs that were laid on the leaf surface under the web. Thus, by altering their oviposition behaviour in response to predator cues, females of T. evansi protect their offspring

Antipredator behaviours of a spider mite in response to cues of dangerous and harmless predators

Prey are known to invest in costly antipredator behaviour when perceiving cues of dangerous, but not of relatively harmless predators. Whereas most studies investigate one type of antipredator behaviour, we studied several types (changes in oviposition, in escape and avoidance behaviour) in the spider mite Tetranychus evansi in response to cues from two predatory mites. The predator Phytoseiulus longipes is considered a dangerous predator for T. evansi, whereas Phytoseiulus macropilis has a low predation rate on this prey, thus is a much less dangerous predator. Spider mite females oviposited less on leaf disc halves with predator cues than on clean disc halves, independent of the predator species. On entire leaf discs, they laid fewer eggs in the presence of cues of the dangerous predator than on clean discs, but not in the presence of cues of the harmless predator. Furthermore, the spider mites escaped more often from discs with cues of the dangerous predator than from discs without predator cues, but they did not escape more from discs with cues of the harmless predator. The spider mites did not avoid plants with conspecifics and predators. We conclude that the spider mites displayed several different antipredator responses to the same predator species, and that some of these antipredator responses were stronger with cues of dangerous predators than with cues of harmless predators