Protamine/DNA/Niosome Ternary Nonviral Vectors for Gene Delivery to the Retina: The Role of Protamine.

The present study aimed to evaluate the incorporation of protamine into niosome/DNA vectors to analyze the potential application of this novel ternary formulation to deliver the pCMS-EGFP plasmid into the rat retina. Binary vectors based on niosome/DNA and ternary vectors based on protamine/DNA/niosomes were prepared and physicochemically characterized. In vitro experiments were performed in ARPE-19 cells. At 1:1:5 protamine/DNA/niosome mass ratio, the resulted ternary vectors had 150 nm size, positive charge, spherical morphology, and condensed, released, and protected the DNA against enzymatic digestion. The presence of protamine in the ternary vectors improved transfection efficiency, cell viability, and DNA condensation. After ocular administration, the EGFP expression was detected in different cell layers of the retina depending on the administration route without any sign of toxicity associated with the formulations. While subretinal administration transfected mainly photoreceptors and retinal pigment epithelial cells at the site of injection, intravitreal administration produced a more uniform distribution of the protein expression through the inner layers of the retina. The protein expression in the retina persisted for at least one month after both administrations. Our study highlights the flattering properties of protamine/DNA/niosome ternary vectors for efficient and safe gene delivery to the rat retina.

Leukoencephalopathy due to oral methotrexate.

Methotrexate (MTX) is considered the main agent for the treatment of rheumatoid arthritis (RA). Neurotoxicity is often mild, but severe encephalopathy can develop, especially with intrathecal or intravenous administration. In rare cases, this syndrome has been observed in patients on long-term low-dose oral administration. A 68-year-old male was diagnosed with RA and on treatment with oral MTX 25 mg weekly for 4 years. The patient started with progressive dysarthria, ataxia and cognitive dysfunction. Complementary tests were normal. Magnetic resonance imaging (MRI) showed hyperintense lesions in both cerebellar hemispheres on T2-weighted and FLAIR images with a diffusion restriction on diffusion-weighted imaging (DWI) and on the apparent diffusion coefficient map (ADC). On postgadolinium T1-weighted images, there were mild enhancements. Spectroscopy showed a demyelinating pattern. A pharmacogenetics determination was made, showing a heterozygous genotype in the MTHFR and ABCB1 genes. Medication with antirheumatic drug was stopped immediately on admission, and the patient gradually improved. MTX-induced leukoencephalopathy can occur even with low-dose administration. The exact pathogenic mechanism is still unknown, but it is hypothesised that it could be the result of a cumulative toxic effect on the blood-brain barrier. The nature of the relationship between the polymorphism and CNS toxicity is still unclear, and thus, further studies are warranted. Often located in the occipital lobes, the involvement of the cerebellum is quite rare. Early recognition of the condition and withdrawal of the drug lead to a better prognosis.

Number and spatial distribution of intrinsically photosensitive retinal ganglion cells in the adult albino rat.

Intrinsically photosensitive retinal ganglion cells (ipRGCs) respond directly to light and are responsible of the synchronization of the circadian rhythm with the photic stimulus and for the pupillary light reflex. To quantify the total population of rat-ipRGCs and to assess their spatial distribution we have developed an automated routine and used neighbour maps. Moreover, in all analysed retinas we have studied the general population of RGCs - identified by their Brn3a expression - and the population of ipRGCs - identified by melanopsin immunodetection - thus allowing the co-analysis of their topography. Our results show that the total mean number ± standard deviation of ipRGCs in the albino rat is 2047 ± 309. Their distribution in the retina seems to be complementary to that of Brn3a(+)RGCs, being denser in the periphery, especially in the superior retina where their highest densities are found in the temporal quadrant, above the visual streak. In addition, by tracing the retinas from both superior colliculi, we have also determined that 90.62% of the ipRGC project to these central targets.

Axotomy-induced retinal ganglion cell death in adult mice: quantitative and topographic time course analyses.

The fate of retinal ganglion cells after optic nerve injury has been thoroughly described in rat, but not in mice, despite the fact that this species is amply used as a model to study different experimental paradigms that affect retinal ganglion cell population. Here we have analyzed, quantitatively and topographically, the course of mice retinal ganglion cells loss induced by intraorbital nerve transection. To do this, we have doubly identified retinal ganglion cells in all retinas by tracing them from their main retinorecipient area, the superior colliculi, and by their expression of BRN3A (product of Pou4f1 gene). In rat, this transcription factor is expressed by a majority of retinal ganglion cells; however in mice it is not known how many out of the whole population of these neurons express it. Thus, in this work we have assessed, as well, the total population of BRN3A positive retinal ganglion cells. These were automatically quantified in all whole-mounted retinas using a newly developed routine. In control retinas, traced-retinal ganglion cells were automatically quantified, using the previously reported method (Salinas-Navarro et al., 2009b). After optic nerve injury, though, traced-retinal ganglion cells had to be manually quantified by retinal sampling and their total population was afterwards inferred. In naïve whole-mounts, the mean (±standard deviation) total number of traced-retinal ganglion cells was 40,437(±3196) and of BRN3A positive ones was 34,697(±1821). Retinal ganglion cell loss was first significant for both markers 5 days post-axotomy and by day 21, the last time point analyzed, only 15% or 12% of traced or BRN3A positive retinal ganglion cells respectively, survived. Isodensity maps showed that, in control retinas, BRN3A and traced-retinal ganglion cells were distributed similarly, being densest in the dorsal retina along the naso-temporal axis. After axotomy the progressive loss of BRN3A positive retinal ganglion cells was diffuse and affected the entire retina. In conclusion, this is the first study assessing the values, in terms of total number and density, of the retinal ganglion cells surviving axotomy from 2 till 21 days post-lesion. Besides, we have demonstrated that BRN3A is expressed by 85.6% of the total retinal ganglion cell population, and because BRN3A positive retinal ganglion cells show the same spatial distribution and temporal course of degeneration than traced ones, BRN3A is a reliable marker to identify, quantify and assess, ex-vivo, retinal ganglion cell loss in this species.

[Post-transplant lymphoproliferative disorders in renal transplantation: two decades of experience]. / Enfermedad linfoproliferativa postrasplante renal. Dos décadas de experiencia.

INTRODUCTION: Post-transplant lymphoproliferative disease (PTLD) represents a heterogeneous group of diseases characterised by a proliferation of lymphocytes occurring after solid organ transplantation. Most cases of PTLD are B-cell and their development has been closely associated with the Epstein-Barr virus (EBV), whose proliferation is encouraged by the inhibition of the cytotoxic function of T lymphocytes due to immunosuppressive drug treatment for transplant recipients. Several risk factors have been described for the development of this disorder, such as the seronegative state of the EBV receptor, the degree of overall net immunosuppression, especially with the use of monoclonal and polyclonal antibodies, acute rejection and cytomegalovirus (CMV) disease. MATERIAL AND METHOD: We studied the incidence of PTLD and its relationship with EBV as well as its evolution and possible risk factors in 1176 adult recipients of cadaveric renal transplantation performed in our hospital between 1988 and 2009, with a follow-up of 1-255 months. The presence of EBV in the lymphoproliferative tissue was determined using in situ hybridisation. We analysed the incidence of PTLD over two time periods, 1988-1998 and 1999-2009 with 472 and 704 patients respectively. RESULTS: A total of 28 recipients (2.38%), 22 men and 6 women with a mean age of 46.5 (15.36) years (18-70 years) with a mean post-transplant evolution of 72.9 (56.3) months (1-180 months), developed PTLD. Thirteen (46.4%) did not show any of the classic risk factors described. The presence of EBV in lymphoproliferative tissue was detected in 18 out of 26 patients studied (69.2%). In terms of histology, 25 out of 28 were type B (89.2%). Ten out of 28 patients diagnosed (35.7%) received treatment with rituximab, six died during the follow-up, five as a direct result of their illness. The incidence for the two time periods was very similar for both groups, with 0.003922 cases/year-patient in the 1988-1998 period and 0.003995 cases/year-patient in the 1999-2009 period. Overall post-transplant survival for patients with PTLD was 73.6% at 5 years and 36.9% at 10 years, versus 87.8% and 75.9% for disease-free recipients (P<.0001). We calculated a graft survival of 62.6% at 5 years and 27.3% at 10 years versus 72.4% and 53.9% for grafts in disease-free recipients (P<.0001). In our study, patient survival one year after presenting the disease was 30.9% and 23.2% at year two. For the graft, survival was 15.5% and 7.7%, respectively. CONCLUSIONS: We conclude that PTLD is a disorder that is generally type B; it is significantly associated with EBV. Its incidence has not changed over time and half of all PTLD cases had no identifiable risk factors, which led to a poor prognosis despite the development of new treatments.

The influence of the polar head-group of synthetic cationic lipids on the transfection efficiency mediated by niosomes in rat retina and brain.

The development of novel non-viral delivery vehicles is essential in the search of more efficient strategies for retina and brain diseases. Herein, optimized niosome formulations prepared by oil-in water (o/w) and film-hydration techniques were characterized in terms of size, PDI, zeta potential, morphology and stability. Three ionizable glycerol-based cationic lipids containing a primary amine group (lipid 1), a triglycine group (lipid 2) and a dimethylamino ethyl pendent group (lipid 3) as polar head-groups were part of such niosomes. Upon the addition of pCMS-EGFP plasmid, nioplexes were obtained at different cationic lipid/DNA ratios (w/w). The resultant nioplexes were further physicochemically characterized and evaluated to condense, release and protect the DNA against enzymatic digestion. In vitro experiments were performed to evaluate transfection efficiency and cell viability in HEK-293, ARPE-19 and PECC cells. Interestingly, niosome formulations based on lipid 3 showed better transfection efficiencies in ARPE-19 and PECC cells than the rest of cationic lipids showed in this study. In vivo experiments in rat retina after intravitreal and subretinal injections together with in rat brain after cerebral cortex administration showed promising transfection efficiencies when niosome formulations based on lipid 3 were used. These results provide new insights for the development of non-viral vectors based on cationic lipids and their applications for efficient delivery of genetic material to the retina and brain.

Selective innervation of retinorecipient brainstem nuclei by retinal ganglion cell axons regenerating through peripheral nerve grafts in adult rats.

The pattern of axonal regeneration, specificity of reinnervation, and terminal arborization in the brainstem by axotomized retinal ganglion cell axons was studied in rats with peripheral nerve grafts linking the retina with ipsilateral regions of the brainstem, including dorsal and lateral aspects of the diencephalon and lateral aspect of the superior colliculus. Four to 13 months later, regenerated retinal projections were traced using intraocular injection of cholera toxin B subunit. In approximately one-third of the animals, regenerated retinal axons extended into the brainstem for distances of up to 6 mm. Although axons followed different patterns of ingrowth depending on their site of entry to the brainstem, within the pretectum, they innervated preferentially the nucleus of the optic tract and the olivary pretectal nucleus in which they formed two types of terminal arbors. Within the superior colliculus, axons extended laterally and formed a different terminal arbor type within the stratum griseum superficiale. In the remaining two-thirds of the animals, retinal fibers formed a neuroma-like structure at the site of entry into the brainstem, or a few fibers extended for very short distances within the neighboring neuropil. These experiments suggest that regenerated retinal axons are capable of a highly selective reinnervation pattern within adult denervated retinorecipient nuclei in which they form well defined terminal arbors that may persist for long periods of time. In addition, these studies provide the anatomical correlate for our previous functional study on the re-establishment of the pupillary light reflex in this experimental paradigm.

[Enzyme replacement therapy in Fabry's disease]. / Terapia de sustitución enzimática en la enfermedad de Fabry: evaluación clínico-histológica tras 18 meses de terapia.

We report a 56-year-old man with history of chronic renal failure, who was diagnosed to have Fabry's disease after performing a percutaneous kidney biopsy. The diagnosis was confirmed by the deficient level of activity of alpha-galactosidase A and by the identification of the mutation. A enzime replacement therapy with alpha-galactosidase A was administered. After 18 months of treatment, a second kidney biopsy was performed showing renal deposits of globotriaosylceramide (we did not evaluate the percentage of histologic clearance of the deposits). Six months after the end of the therapy, a reduction in the impairment of renal function is observed, and the classic manifestations of the disease are absent.

[Antibiotic susceptibility of Streptococcus pneumoniae in healthy carrier children in Murcia (Spain)]. / Sensibilidad de Streptococcus pneumoniae en niños portadores sanos en Murcia (España).

INTRODUCTION AND OBJECTIVES: Streptococcus pneumoniae (SP) is a human pathogen that involves a high use of antibiotics. The objective of the study was to determine the susceptibility to commonly used antibiotics and their associated risk factors, in order to promote rational use of antibiotics. PATIENTS AND METHODS: In A multicentre study was conducted in summer 2009 and winter 2010 on children attending paediatric clinics in the Region of Murcia. A nasopharyngeal sample was collected and an epidemiological questionnaire was completed. The study included 1562 children aged 1 and 4 years old. RESULTS: Almost one-third (31.3%, 489/1562) of children were nasal carriers. A sensitivity study was carried out on 376 isolates, of which 343 were serotyped. Almost two-thirds (61.7%, 964/1562) of children had received at least one dose of PCV7 (heptavalent pneumococcal conjugate vaccine), and 12.8% (44/343) of the isolates belonged to PCV7 serotypes. The prevalence rates of penicillin resistance (meningitis infections criteria CMI>0.06mg/L) were 28.1%; however, this percentage was 54% in PCV7 serotypes. None of the isolates had (MIC >2mg/L), so prevalence rates of susceptibility with non-meningitis infections criteria were 100%. There was a high percentage of erythromycin resistance (45.7%). The factors favouring resistance to penicillin and cefotaxime were the consumption of antibiotics in the previous month and the carrying of vaccine serotypes. On the other hand, the age of 4 years old was a protective factor of resistance. The 14, 35B, 19A, 15A, and 19F serotypes were less susceptible to penicillin. CONCLUSIONS: Both oral amoxicillin given to outpatients and intravenous penicillin or ampicillin to hospitalized patients are excellent options for the treatment of non-meningeal infections, as seen with pneumonia in these kinds of environments, where there is low incidence of isolates highly resistant to penicillin (CMI ≥ 2mg/L).

[Presence of hepatitis C virus in renal tissue in membranoproliferative glomerulonephritis and cryoglobulinemia]. / Presencia del virus de la hepatitis C en tejido renal en glomerulonefritis membranoproliferativa y crioglobulinemia.

Although hepatitis C virus infection has been documented in several extrahepatic diseases, the deposition of HCV RNA in glomerular structures has proved to be difficult to demonstrate. We report a patient with membranoproliferative glomerulonephritis, type III circulating cryoglobulins and hepatitis C virus infection with detection of HCV RNA in serum, cryoprecipitate and renal tissue using specific RT-PCR technique. These data confirm that HCV could have a direct role in renal damage.

[Cartilaginous tumors of the larynx. A report of 3 cases]. / Tumores cartilaginosos de la laringe. A propósito de tres casos.

Cartilaginous tumours of the larynx are very seldom encountered. Worldwide literature report until now no more than 250 cases. The greatest number of cases (72%) are benign and localized on cricoid cartilage. They are characterized by its slow pace spread and chondrosarcomata shows scant tendency to metastasize, prevailing, instead, local increase. Best treatment resulted the conservative surgery. We report 3 cases (1 chondroma and 2 low ranked chondrosarcomata) diagnosed and treated in our Hospital in the last 15 years. Clinical and anatomopathologic features are exposed and the management as well, and also the postoperative course of each patient.

[Neck phlebectasia]. / Flebectasia cervical.

Neck phlebectasia is an infrequent anomaly of the venous system, possibly a congenital condition, becoming apparent as a neck mass triggered by the Valsalva maneuver or any other exploratory afford with closed nose. Commonly localized in the jugular venous system, although it can turn-up, the ectasia, to other cervicofacial veins. In this paper are reported 3 neck phlebectasis including one of them affecting the anterior facial vein, occurrence exceedingly uncommon, of which case we don't know even a single reference in the literature. We make a perusal of the subject's bibliography and also discuss the clinic, diagnostic and therapeutical most important features of this entity.

[Metastasis in submandibular gland from a leiomyosarcoma of the uterus]. / Metástasis a glándula submaxilar de leiomiosarcoma uterino.

Two general types of metastases should be distinguished in metastatic salivary gland tumors: one of them are tumors originating in the head and neck region, and the other are tumors from distant tumor sites. Distant metastasis affecting the submandibular gland are a rare entity. We report a case of the uterus leiomyosarcoma which metastatised in the submandibular gland.

[Allergic fungal sinusitis]. / Sinusitis fúngica alérgica.

Allergic fungal sinusitis is a recently described clinical entity that has gained increased attention as a cause of chronic sinusitis. Consist in a benign noninvasive sinus disease related to a hypersensitivity reaction to fungal antigens. It should be suspected in any atopic patient with refractory nasal polyps. Computed tomography (CT) findings are characteristics, but not diagnostic. Diagnosis requires show allergic mucin in the histopathologic examination and hiphae in special fungal stains. The suitable treatment includes the allergic mucin removal and sinus aeration accomplished endoscopically, perioperative systemic steroids and immunotherapy with fungal antigens. We present a case of this kind of chronic sinusitis describing the characteristic histopathologic and radiologic findings, the pathogenic theories and recent advances in immunotherapy.

[Presentation of multiple oncocytic type laryngeal cysts. Clinical and histopathological findings]. / Presentación múltiple de quistes laríngeos de tipo oncocítico. Hallazgos clínicos e histopatológicos.

Oncocytic cysts are a histologically well-defined subgroup of cystic lesions of the larynx. Oncocytic cysts of the larynx are rare, clinically similar to simple laryngeal cysts, and occur as a casual finding of pathology studies. Multiple oncocytic cysts have rarely been described. Microscopic examination of laryngeal biopsies showed cysts within the lamina propria lined by oncocytic epithelium. The differential diagnosis and pathogenesis of oncocytic cysts is discussed and other laryngeal cystic lesions are reviewed.

A novel cationic niosome formulation for gene delivery to the retina.

Niosomes represent a recent promising approach for gene delivery purposes. We elaborated on a novel niosome formulation based on the 2,3-di(tetradecyloxy)propan-1-amine cationic lipid, combined with squalene and polysorbate 80 to evaluate the transfection efficiency in rat retinas. Niosomes prepared by the solvent emulsification-evaporation technique were mixed with the pCMSEGFP plasmid to form lipoplexes which were characterized in terms of morphology, size, surface charge, and DNA condensation, protection and release. In vitro studies were conducted to evaluate transfection efficiency, viability and internalization mechanism in HEK-293 and ARPE-19 cells. The efficacy of the most promising formulation was evaluated in rat eyes by monitoring the expression of the EGFP after intravitreal and subretinal injections. Lipoplexes at 15/1 ratio were 200nm in size, 25mV in zeta potential and exhibited spherical morphology. At this ratio, niosomes condensed and protected the DNA from enzymatic digestion. Lipoplexes successfully transfected HEK-293 and specially ARPE-19 cells, without affecting the viability. Whereas lipoplexes entered mainly retinal cells by clathrin-mediated endocytosis, HEK-293 cells showed a higher caveolae-dependent entry. After ocular administration, the expression of EGFP was detected in different cells of the retina depending on the administration route. This novel niosome formulation represents a promising approach to deliver genetic material into the retina to treat inherited retinal diseases.

A computerized analysis of the entire retinal ganglion cell population and its spatial distribution in adult rats.

In adult albino (SD) and pigmented (PVG) rats the entire population of retinal ganglion cells (RGCs) was quantified and their spatial distribution analyzed using a computerized technique. RGCs were back-labelled from the optic nerves (ON) or the superior colliculi (SCi) with Fluorogold (FG). Numbers of RGCs labelled from the ON [SD: 82,818+/-3,949, n=27; PVG: 89,241+/-3,576, n=6) were comparable to those labelled from the SCi [SD: 81,486+/-4,340, n=37; PVG: 87,229+/-3,199; n=59]. Detailed methodology to provide cell density information at small scales demonstrated the presence of a horizontal region in the dorsal retina with highest densities, resembling a visual streak.

Retinal ganglion cell population in adult albino and pigmented mice: a computerized analysis of the entire population and its spatial distribution.

UNLABELLED: In adult Swiss albino and C57 pigmented mice, RGCs were identified with a retrogradely transported neuronal tracer applied to both optic nerves (ON) or superior colliculi (SCi). After histological processing, the retinas were prepared as whole-mounts, examined and photographed under a fluorescence microscope equipped with a motorized stage controlled by a commercial computer image analysis system: Image-Pro Plus((R)) (IPP). Retinas were imaged as a stack of 24-bit color images (140 frames per retina) using IPP with the Scope-Pro plug-in 5.0 and the images montaged to create a high-resolution composite of the retinal whole-mount when required. Single images were also processed by specific macros written in IPP that apply a sequence of filters and transformations in order to separate individual cells for automatic counting. Cell counts were later transferred to a spreadsheet for statistical analysis and used to generate a RGC density map for each retina. RESULTS: The mean total numbers of RGCs labeled from the ON, in Swiss (49,493+/-3936; n=18) or C57 mice (42,658+/-1540; n=10) were slightly higher than the mean numbers of RGCs labeled from the SCi, in Swiss (48,733+/-3954; n=43) or C57 mice (41,192+/-2821; n=42), respectively. RGCs were distributed throughout the retina and density maps revealed a horizontal region in the superior retina near the optic disk with highest RGC densities. In conclusion, the population of mice RGCs may be counted automatically with a level of confidence comparable to manual counts. The distribution of RGCs adopts a form of regional specialization that resembles a horizontal visual streak.

Enfermedad linfoproliferativa postrasplante renal. Dos décadas de experiencia / Post-transplant lymphoproliferative disorders in renal transplantation: two decades of experience

Introducción: La enfermedad linfoproliferativa postrasplante (ELP) representa un grupo heterogéneo de enfermedades que se caracterizan por una proliferación de linfocitos que se presenta después del trasplante de órganos sólidos. La mayoría de los casos de ELP son de estirpe B y su desarrollo se ha asociado estrechamente con el virus de Epstein-Barr (VEB), cuya proliferación se vería favorecida por la inhibición de la función citotóxica de los linfocitos T debido a la inmunosupresión farmacológica a la que se somete a los receptores de trasplante. Se han descrito varios factores de riesgo para el desarrollo de esta entidad, como son la seronegatividad del receptor para VEB, el grado de inmunosupresión neta global, sobre todo con el uso de anticuerpos monoclonales o policlonales, el rechazo agudo y la enfermedad por citomegalovirus (CMV). Material y métodos: Hemos estudiado la incidencia de ELP y su relación con el VEB, así como su evolución y los posibles factores de riesgo en su desarrollo, en 1.176 receptores adultos de trasplante renal de cadáver realizados en nuestro hospital, entre 1988 y 2009, con un seguimiento de uno a 255 meses. Se determinó la presencia de VEB en el tejido linfoproliferativo mediante hibridación. Analizamos la incidencia de ELP en dos períodos de tiempo, 1988-1998 y 1999-2009 con 472 y 704 pacientes, respectivamente. Resultados: Un total de 28 receptores (2,38 %), 22 hombres y 6 mujeres, con una edad media de 46,5 ± 15,36 años (18-70 años) y con una evolución media postrasplante de 72,9 ± 56,3 meses (1-180 meses), desarrollaron ELP. Trece de ellos (46,4%) no presentaban ninguno de los factores de riesgo clásicos descritos. Se detectó la presencia de VEB en el tejido linfoproliferativo de 18 de los 26 pacientes estudiados (69,2%). Respecto a su estirpe histológica 25 de los 28 eran tipo B (89,2%). Diez de los 28 pacientes diagnosticados (35,7%) recibieron tratamiento con rituximab, seis de ellos fallecieron durante el seguimiento, cinco como consecuencia directa de su enfermedad. Calculada la densidad de incidencia en los dos períodos, ésta fue muy similar en ambos grupos, de 0,003922 casos/años-paciente en el período 1988-1998 y de 0,003995 casos/años-paciente en el período 1999-2009. La supervivencia global postrasplante del paciente que presentó ELP fue del 73,6% a los 5 años y del 36,9 % a los 10 años frente al 87,8% y al 75,9% del receptor libre de enfermedad (p <0,0001). Evidenciamos una supervivencia del injerto del 62,6% a los 5 años y del 27,3% a los 10 años frente al 72,4% y al 53,9% de los injertos de los receptores libres de enfermedad (p <0,0001). En nuestra serie, la supervivencia del paciente al año de presentar la enfermedad fue del 30,9%, y del 23,2% al segundo año, y para el injerto del 15,5% del 7,7%, respectivamente. Conclusiones: Concluimos que la ELP es una entidad en su mayoría de estirpe B, asociada de forma significativa con el VEB, cuya incidencia no ha variado en el tiempo y en la que en la mitad de los casos no se identifican factores de riesgo, condicionando muy mal pronóstico a pesar de los nuevos tratamientos desarrollado (AU)

Introduction: Post-transplant lymphoproliferative disease (PTLD) represents a heterogeneous group of diseases characterised by a proliferation of lymphocytes occurring after solid organ transplantation. Most cases of PTLD are B-cell and their development has been closely associated with the Epstein-Barr virus (EBV), whose proliferation is encouraged by the inhibition of the cytotoxic function of T lymphocytes due to immunosuppressive drug treatment for transplant recipients. Several risk factors have been described for the development of this disorder, such as the seronegative state of the EBV receptor, the degree of overall net immunosuppression, especially with the use of monoclonal and polyclonal antibodies, acute rejection and cytomegalovirus (CMV) disease. Material and method: We studied the incidence of PTLD and its relationship with EBV as well as its evolution and possible risk factors in 1176 adult recipients of cadaveric renal transplantation performed in our hospital between 1988 and 2009, with a follow-up of 1-255 months. The presence of EBV in the lymphoproliferative tissue was determined using in situ hybridisation. We analysed the incidence of PTLD over two time periods, 1988-1998 and 1999-2009 with 472 and 704 patients respectively. Results: A total of 28 recipients (2.38%), 22 men and 6 women with a mean age of 46.5 (15.36) years (18-70 years) with a mean post-transplant evolution of 72.9 (56.3) months (1-180 months), developed PTLD. Thirteen (46.4%) did not show any of the classic risk factors described. The presence of EBV in lymphoproliferative tissue was detected in 18 out of 26 patients studied (69.2%). In terms of histology, 25 out of 28 were type B (89.2%). Ten out of 28 patients diagnosed (35.7%) received treatment with rituximab, six died during the follow-up, five as a direct result of their illness. The incidence for the two time periods was very similar for both groups, with 0.003922 cases/year-patient in the 1988-1998 period and 0.003995 cases/year-patient in the 1999-2009 period. Overall post-transplant survival for patients with PTLD was 73.6% at 5 years and 36.9% at 10 years, versus 87.8% and 75.9% for disease-free recipients (P<.0001). We calculated a graft survival of 62.6% at 5 years and 27.3% at 10 years versus 72.4% and 53.9% for grafts in disease-free recipients (P<.0001). In our study, patient survival one year after presenting the disease was 30.9% and 23.2% at year two. For the graft, survival was 15.5% and 7.7%, respectively. Conclusions: We conclude that PTLD is a disorder that is generally type B; it is significantly associated with EBV. Its incidence has not changed over time and half of all PTLD cases had no identifiable risk factors, which led to a poor prognosis despite the development of new treatments (AU)