Fungal infections in renal transplant patients

Organ transplantation has always been considered to be the standard therapeutic interventions in patients with end-stage organ failure. In 2008, more than 29,000 organ transplants were performed in US. Survival rates among transplant recipients have greatly improved due to better understanding of transplant biology and more effective immunosuppressive agents. After transplant, the extent of the immune response is influenced by the amount of interleukin 2 (IL-2) being produced by the T-helper cells. Transplant immunosuppressive therapy primarily targets T cell-mediated graft rejection. Calcineurin inhibitor, which includes cyclosporine, pimecrolimus and tacrolimus, impairs calcineurin-induced up-regulation of IL-2 expression, resulting in increased susceptibility to invasive fungal diseases. This immunosuppressive state allows infectious complication, leading to a high mortality rate. Currently, overall mortality due to invasive fungal infections (IFIs) in solid organ transplant recipients ranges between 25% and 80%. The risk of IFI following renal transplant is associated with the dosage of immunosuppressive agents given, environmental factors and post-transplant duration. Most fungal infections occur in the first 6 months after transplant because of the use of numerous immunosuppressors. Candida spp. and Cryptococcus spp. are the yeasts most frequently isolated, while most frequent filamentous fungi (molds) isolated are Aspergillus spp. The symptoms of systemic fungal infections are non-specific and early detection of fungal infections and proper therapy are important in improving survival and reducing mortality. This article will provide an insight on the risk factors and clinical presentation, compare variation in treatment of IFIs in renal transplant patients, and evaluate the role of prophylactic therapy in this group of patients. We also report the course and management of two renal transplant recipients admitted to Staten Island University Hospital, both of whom developed pulmonary complications secondary to Aspergillus infection

Visualization of the renal vein during pyelography after nephrostomy: a case report

<p>Abstract</p> <p>Introduction</p> <p>We present a case of pyelovenous backflow after nephrostomy. To the best of our knowledge, this is the first documented case of renal vein visualization after a nephrostomic placement.</p> <p>Case presentation</p> <p>A 55-year-old Caucasian man presented with symptoms of pyelonephritis with an obstructing ureteral stone. A nephrostomy was performed. During an injection of contrast agent in his left caliceal system, his left renal vein was visualized. A repeat pyelography with an injection contrast material at low pressure failed to show the same finding. This radiological finding is due to the occurrence of "pyelovenous backflow".</p> <p>Conclusion</p> <p>This phenomenon is usually described in the setting of renal vein thrombosis, renal vein hypertension due to the "nutcracker phenomenon", or a reduced renal blood flow. Examination by microscopy shows the presence of tears in the fornix of the pelvic cavity that extend into the kidney parenchyma. Five types of renal backflow are described in the literature: pyelovenous, pyelolymphatic, pyelotubular, pyelointerstitia and pyelosinus. Injection of contrast material at high pressure may cause a fornix to flow into the tubules, or cause its rupture and flow into the venous system.</p

Investigation of Left Ventricle Flow Dynamics in the Presence of Mitral Annular Calcification

Mitral Annular Calcification (MAC) is a degenerative heart disease corresponding to a deformation and narrowing of the mitral valve. Up to 42% of people aged over 65 have it, and 60% of people aged over 85. The aim of the present work was to understand the flow downstream of a calcified valve and to investigate how both the severity and the orientation affect the characteristics of the velocity field, vorticity field, viscous energy loss, vortex formation time, viscous shear stress, particle path, and shear accumulation. For the purpose of this experimental thesis, particle image velocimetry was conducted at physiological flow and pressure conditions in two stages. The first stage is the in vitro experiment with seven different mitral valve configurations: (1) normal, (2) mild, (3) moderate with two orientations, (4) severe with three different orientations. Results show that compared with a normal case the instantaneous velocity, vorticity, and shear stress fields in addition to the energy loss evolution and vortex formation time significantly increase with MAC severities. It also showed, that keeping the same severity but modifying the orientation of the mitral valve also significantly lead to sub-optimal hemodynamic configurations. Findings of this study indicate that the presence of MAC and orientation in the mitral valve significantly alters the hemodynamics in the left ventricle. This study sheds some light on the crucial rule that the orientation of the mitral valve plays in the severity assessment. The second stage is experiments with models of patient specific valves with three different configurations (1) normal, (2) moderate MAC and (3) severe MAC. Results show that compared with a normal case the velocity and vorticity fields increased with MAC severities. Interestingly, it also showed, that the moderate case had higher averaged energy loss than that of the severe case. The energy loss of the severe was even less than that of the normal. In conclusion, this study advances the current state of understanding of flow through calcified mitral valve by investigating how MAC affects the hemodynamics in the LV. Results can be used as the foundation for further investigations in order to better clinically evaluate mitral annular calcification

An Overlapping Case of Lupus Nephritis and IgG4-Related Kidney Disease

We report a case of a 71-year-old Filipino female who was admitted to the hospital for abdominal pain, vomiting and diarrhea of 8 days duration. The patient was found to have marked acute kidney injury (AKI), which required hemodialysis in the next 3 days. Extensive workup revealed hematuria, subnephrotic range proteinuria, elevated anti-nuclear antibody (ANA) and elevated total immunoglobulin G (IgG) levels, with normal IgG4 and anti-dsDNA levels. On kidney biopsy, mild membranous glomerulonephritis was found, along with autoimmune tubulointerstitial nephritis (TIN) with a full-house pattern of immune deposits. These findings were suggestive of lupus interstitial nephritis. However, IgG4+ plasma cells were detected in the interstitium by immunostaining, favoring a diagnosis of IgG4-related kidney disease (IgG4-RKD). Our case highlights the difficulty in differentiating lupus nephritis (LN) from IgG4-RKD in some patients, raising the suspicion that these two entities can co-exist

Pseudoleukocytosis secondary to hepatitis C-associated cryoglobulinemia: a case report

<p>Abstract</p> <p>Introduction</p> <p>Laboratory tests play a central role in assessing a patient and orienting the diagnostic evaluation. We report a case where the discrepancy between the manual and automatic cell count gave a hint to the final diagnosis.</p> <p>Case presentation</p> <p>A 55-year-old Caucasian man, known to have hepatitis C, was admitted with acute respiratory failure secondary to acute pulmonary edema and diffuse petechial rash of the lower extremities for the previous 2 months. The initial laboratory tests showed acute renal failure (creatinine of 2.6 mg/dL). During his hospital stay, the patient had a fluctuating white blood cell count with a recorded value of 96,000 cells/mL. On a peripheral smear, the blood cell count was in the normal range. The acute renal failure was secondary to membranoproliferative glomerulonephritis secondary to essential mixed cryoglobulinemia diagnosed by biopsy. The complete blood count values, performed by Beckman/Coulter GenS, were falsely high due to precipitation of plasma cryoglobulins at room temperature. This spurious leukocytosis was previously described in several case reports, but values as high as 96,000 cells/mL were never reported.</p> <p>Conclusion</p> <p>The presence of cryoglobulins in the blood creates a clinical challenge for the interpretation of several laboratory tests. Pseudoleukocytosis secondary to cryoglobulinemia has been observed in several reported cases with white blood cell counts up to 54,000 cells/mL at room temperature and 85,600 cells/mL at 4°C. If the cryoglobulin precipitates rapidly, aggregated cryoglobulin particles may be interpreted as blood cells. We report the first patient with pseudoleukocytosis secondary to hepatitis C cryoglobulinemia with a spurious leukocytosis of 96,000 cells/mL at room temperature. Other laboratory tests could also be affected: underestimation of true erythrocyte sedimentation rate, pseudothrombocytosis and pseudolymphocytosis. The precipitation can remove the hepatitis C virus and the antibody of cryoglobulins from serum leading to a false negative result. Any discrepancy between the automated and manual white blood cell count should lead to the suspicion of cryoglobulinemia in the clinical setting.</p

Place de la néphrolithotomie à ciel ouvert dans le traitement du calcul coralliforme: à propos d'une série de 53 patients

Le but de notre étude est de discuter la place de la chirurgie ouverte dans le traitement de la lithiase rénale, et notamment le coralliforme complexe, devant l'avènement de nouvelles techniques moins invasives. Nous rapportons une série de 53 calculs coralliformes colligés au sein de notre formation durant une période de 7 ans, de janvier 2011 au janvier 2018, traités par néphrolithotomie ouverte par lombotomie. La moyenne d'hospitalisation postopératoire était de 10 jours. Les suites postopératoires immédiates et précoces étaient simples chez 36 patients, 6 patients ont nécessités une transfusion sanguin, 2 ont représenté un sepsis sévère en postopératoire, 5 cas une infection de la paroi et 4 cas une fistule urinaire jugulée secondairement par un drainage endoscopique. Les calculs résiduels sont retrouvés dans 9 cas (16,9%). Ces calculs sont traités essentiellement par la lithotripsie extra corporelle. Les suites tardives étaient marquées par une atrophie rénale chez 2 patients, une récidive lithiasique chez 9 patients. Une amélioration de la clairance de créatinine chez 9 patients, et une légère aggravation chez 5 patients. La chirurgie à ciel ouvert de la lithiase rénale a de nombreuses complications, elle n'est pas recommandée en première ligne, mais il est important de reconnaître les patients chez lesquels une néphrolithotomie par voie ouverte pourrait représenter un choix valide de traitement

Impacts of Human Body on Antenna Radiation in Indoor Environments : Numerical Modeling and Experimental Validation

International audienceThe presence of human body has an important influence on the wireless communication systems in indoor environments. The need of efficient prediction for such coverage becomes essential. This paper present an efficient electromagnetic indoor propagation modeling, taking into account the presence of human body and the nature of materials of the complex environment, based on the Finite-Difference Time-Domain method. Numerical results are compared with measurement results and show a good agreement

Electromagnetic Propagation Modeling in Office Environment

International audienceWireless propagation modeling is more and more needed for optimal indoor coverage in complex environment (such as offices, classrooms, etc.). Thus the need to predict electromagnetic propagation efficiently and accurately in the presence of obstacles, allowing engineers to planning efficiently the communicating devices. This paper will present a rigorous electromagnetic indoor propagation modeling based on the FDTD (3D) method taking into account the presence of various obstacles. A comparison between numerical results obtained by FDTD code and Ray Tracing software will be presented and compared with measurement results. Computational performance efficiency of these methods will also be discussed