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1.
Clin Transplant ; 38(1): e15206, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38041491

RESUMEN

Existing literature offers conflicting conclusions about whether early acute cellular rejection influences long-term outcomes in liver transplantation. We retrospectively collected donor and recipient data on all adult, first-time liver transplants performed at a single center between 2008 and 2020. We divided this population into two cohorts based on the presence of early biopsy-proven acute cellular rejection (EBPR) within the first 90 days post-transplant and compared outcomes between the groups. There were 896 liver transplants that met inclusion criteria with 112 cases (12.5%) of EBPR. Recipients who developed EBPR had higher biochemical Model for End-Stage Liver Disease scores (28 vs. 24, p < .01), but other donor and recipient characteristics were similar. Recipients with EBPR had similar overall survival compared to patients without EBPR (p = .09) but had decreased graft survival (p < .05). EBPR was also associated with decreased time to first episode of late (> 90 days post-transplant) rejection (p < .0001) and increased vulnerability to bacterial and viral infection (p < .05). In subgroup analysis of recipients with autoimmune indications for liver transplantation, EBPR had a more pronounced association with patient death (hazard ratio [HR] 3.9, p < .05) and graft loss (HR 4.0, p < .01). EBPR after liver transplant is associated with inferior graft survival, increased susceptibility to late rejections, and increased vulnerability to infection.


Asunto(s)
Enfermedad Hepática en Estado Terminal , Trasplante de Hígado , Adulto , Humanos , Trasplante de Hígado/efectos adversos , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Rechazo de Injerto/diagnóstico , Rechazo de Injerto/etiología , Biopsia , Supervivencia de Injerto
2.
Clin Transplant ; 38(9): e15453, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39229690

RESUMEN

PURPOSE: Evaluate cytomegalovirus (CMV) post-prophylaxis surveillance in high-risk (D+/R-) kidney and liver transplant recipients. METHODS: Adult D+/R- patients were included if transplanted between 6/1/15 and 11/30/22 and divided into a pre-CMV-stewardship-era (6/1/15-5/31/18), CMV-stewardship-era (6/1/18-6/30/20), and a surveillance-era (7/1/2020-11/30/2022) then followed through 12 months. The primary objective was to evaluate CMV-related outcomes. The secondary objective was to assess graft and patient survival by era. RESULTS: There were 328 patients in the study period; 133 in the pre-stewardship-era, 103 in the stewardship-era, and 92 in the surveillance-era. Replication rates in the surveillance-era were significantly higher, as anticipated due to increased sampling (pre 38.4%, stewardship 33.0%, surveillance 52.2%, p = 0.02). Time from transplant to first replication was similar (pre 214.0 ± 79.0 days, stewardship 231.1 ± 65.5, surveillance 234.9 ± 61.4, p = 0.29). CMV viral load (VL) at first detection, maximum-VL, and incidence of VL > 100 000 IU/mL were numerically lower in the surveillance era, although not statistically significant. CMV end-organ disease (p < 0.0001) and ganciclovir-resistance (p = 0.002) were significantly lower in the surveillance era than in both previous eras. Rejection was not different between eras (p = 0.4). Graft (p = 0.0007) and patient survival (p = 0.008) were significantly improved in the surveillance era. CONCLUSIONS: Post-prophylaxis surveillance significantly reduced CMV end-organ disease and resistance. Despite observing increased replication rates in the surveillance era, rejection was not significantly different and there was no graft loss or patient mortality at 12 months.


Asunto(s)
Antivirales , Infecciones por Citomegalovirus , Citomegalovirus , Farmacorresistencia Viral , Ganciclovir , Rechazo de Injerto , Supervivencia de Injerto , Trasplante de Riñón , Trasplante de Hígado , Humanos , Infecciones por Citomegalovirus/prevención & control , Infecciones por Citomegalovirus/virología , Infecciones por Citomegalovirus/epidemiología , Masculino , Femenino , Persona de Mediana Edad , Citomegalovirus/aislamiento & purificación , Citomegalovirus/efectos de los fármacos , Antivirales/uso terapéutico , Ganciclovir/uso terapéutico , Estudios de Seguimiento , Trasplante de Hígado/efectos adversos , Factores de Riesgo , Trasplante de Riñón/efectos adversos , Pronóstico , Rechazo de Injerto/prevención & control , Rechazo de Injerto/etiología , Rechazo de Injerto/virología , Complicaciones Posoperatorias/prevención & control , Adulto , Tasa de Supervivencia , Estudios Retrospectivos , Receptores de Trasplantes/estadística & datos numéricos
3.
Transpl Int ; 37: 13087, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39364120

RESUMEN

Given the increasing frequency of simultaneous pancreas-kidney transplants performed in recipients with Type II diabetes and CKD, we sought to evaluate possible differences in the rates of allograft rejection, infection, and surgical complications in 298 Type I (T1D) versus 47 Type II (T2D) diabetic recipients of simultaneous pancreas-kidney transplants between 2006-2017. There were no significant differences in patient or graft survival. The risk of biopsy-proven rejection of both grafts was not significantly different between T2D and T1D recipients (HRpancreas = 1.04, p = 0.93; HRkidney = 0.96; p = 0.93). Rejection-free survival in both grafts were also not different between the two diabetes types (ppancreas = 0.57; pkidney = 0.41). T2D had a significantly lower incidence of de novo DSA at 1 year (21% vs. 39%, p = 0.02). There was no difference in T2D vs. T1D recipients regarding readmissions (HR = 0.77, p = 0.25), infections (HR = 0.77, p = 0.18), major surgical complications (HR = 0.89, p = 0.79) and thrombosis (HR = 0.92, p = 0.90). In conclusion, rejection, infections, and surgical complications after simultaneous pancreas-kidney transplant are not statistically significantly different in T2D compared to T1D recipients.


Asunto(s)
Diabetes Mellitus Tipo 1 , Diabetes Mellitus Tipo 2 , Rechazo de Injerto , Supervivencia de Injerto , Trasplante de Riñón , Trasplante de Páncreas , Complicaciones Posoperatorias , Humanos , Trasplante de Páncreas/efectos adversos , Trasplante de Riñón/efectos adversos , Rechazo de Injerto/etiología , Diabetes Mellitus Tipo 1/cirugía , Diabetes Mellitus Tipo 1/complicaciones , Masculino , Femenino , Persona de Mediana Edad , Adulto , Diabetes Mellitus Tipo 2/complicaciones , Estudios Retrospectivos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/epidemiología , Resultado del Tratamiento , Infecciones/etiología , Infecciones/epidemiología , Incidencia
4.
Ann Surg Oncol ; 30(8): 4737-4743, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36869915

RESUMEN

BACKGROUND: A CD4/CD8 ratio < 0.5 is associated with increased risk of advanced anal disease (AAD) but it is unknown if duration below 0.5 matters. The purpose of this study was to determine if duration of a CD4/CD8 ratio < 0.5 is associated with increased risk of invasive anal cancer (IC) in people living with HIV and high-grade dysplasia (HSIL). METHODS: This single institution, retrospective study used the University of Wisconsin Hospital and Clinics Anal Dysplasia and Anal Cancer Database. Patients with IC versus HSIL alone were compared. Independent variables were mean and percentage of time the CD4/CD8 ratio was < 0.5. Multivariate logistic regression was performed to estimate the adjusted odds of anal cancer. RESULTS: We identified 107 patients with HIV infection and AAD (87 with HSIL, 20 with IC). A history of smoking was significantly associated with the development of IC (95% in patients with IC vs. 64% in patients with HSIL; p = 0.015). Mean time the CD4/CD8 ratio was < 0.5 was significantly longer in patients with IC compared with patients with HSIL (7.7 years vs. 3.8 years; p = 0.002). Similarly, the mean percentage of time the CD4/CD8 ratio was < 0.5 was higher in those with IC versus those with HSIL (80% vs. 55%; p = 0.009). On multivariate analysis, duration CD4/CD8 ratio was < 0.5 was associated with increased odds of developing IC (odds ratio 1.25, 95% confidence interval 1.02-1.53; p = 0.034). CONCLUSIONS: In this retrospective, single-institution study of a cohort of people living with HIV and HSIL, increasing duration the CD4/CD8 ratio was < 0.5 was associated with increased odds of developing IC. Monitoring the number of years the CD4/CD8 ratio is < 0.5 could inform decision making in patients with HIV infection and HSIL.


Asunto(s)
Neoplasias del Ano , Carcinoma in Situ , Infecciones por VIH , Infecciones por Papillomavirus , Humanos , Infecciones por VIH/complicaciones , Estudios Retrospectivos , Linfocitos T CD8-positivos , Infecciones por Papillomavirus/complicaciones
5.
Dis Colon Rectum ; 66(3): 360-365, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36599112

RESUMEN

BACKGROUND: Anal cancer is associated with high-risk human papillomavirus infection and oncoprotein expression. We have identified several protease inhibitors, used to treat HIV, that decrease oncogene expression. OBJECTIVE: The aim of this project is to determine whether saquinavir, a protease inhibitor, results in a treatment response in anal cancer spheroids. DESIGN: K14E6/E7 transgenic mice (n = 5), which express human papillomavirus 16 oncoproteins E6 and E7 in their epithelium, were treated topically at the anus with a carcinogen, 7,12-dimethylbenz[a]anthracene, to promote anal tumor growth. Tumors were excised and digested, and cells were plated. The tumor cells form 3D multicellular aggregates known as spheroids. SETTINGS: This study was performed in an American Association for Accreditation of Laboratory Animal Care-approved facility. INTERVENTIONS: Spheroids were placed in treatment groups: no treatment, vehicle (dimethyl sulfoxide), and 15 µM saquinavir. Spheroids were imaged immediately pretreatment and 24 hours posttreatment. MAIN OUTCOME MEASURES: Spheroid diameters were measured using ImageJ and mean percent reduction was calculated for each spheroid to determine treatment effect on spheroid growth. Analysis of variance using pairwise comparisons was performed with Fisher protected least significant difference tests. RESULTS: The no-treatment (n = 119 spheroids) and vehicle (n = 126 spheroids) groups demonstrated an increase in spheroid diameter during the treatment period. In contrast, spheroids treated with saquinavir (n = 151 spheroids) demonstrated a statistically significant percent reduction compared to the no-treatment ( p < 0.0001) and vehicle ( p = 0.002) groups. LIMITATIONS: A limitation of these data is that some human error is likely present given that images were analyzed by 3 different scientists. CONCLUSIONS: Saquinavir leads to a statistically significant percent reduction in mice anal tumor spheroid growth ex vivo compared to control groups. Protease inhibitor therapy may be an effective treatment or adjuvant therapy to the Nigro protocol to promote anal cancer tumor regression. See Video Abstract at http://links.lww.com/DCR/C82 . EL USO DEL INHIBIDOR DE LA PROTEASA, SAQUINAVIR, PARA TRATAR LOS ESFEROIDES DEL CNCER ANAL DERIVADOS DE RATONES TRANSGNICOS PARA EL VPH: ANTECEDENTES:El cáncer anal está asociado con la infección por el virus del papiloma humano de alto riesgo y la expresión de oncoproteínas. Hemos identificado varios inhibidores de la proteasa, utilizados para tratar el VIH, que disminuyen la expresión del oncogén.OBJETIVO:El objetivo de este proyecto es determinar si los esferoides de cáncer anal responden al tratamiento con inhibidor de la proteasa, Saquinavir.DISEÑO:Ratones transgénicos K14E6/E7 (n = 5), que expresan las oncoproteínas E6 y E7 del VPH16 en su epitelio, fueron tratados tópicamente en el ano con carcinógeno, 7,12 dimetilbenz[a]antraceno, para promover el crecimiento del tumor anal. Los tumores se extirparon y digirieron, y las células se sembraron en placas. Las células tumorales forman agregados multicelulares tridimensionales, conocidos como esferoides.ESCENARIO:Este estudio se realizó en un centro aprobado por la Asociación Estadounidense para la Acreditación de Cuidado de Animales de Laboratorio.INTERVENCIONES:Se colocaron esferoides en grupos de tratamiento: sin tratamiento, vehículo (sulfóxido de dimetilo) y saquinavir 15 µM. Se tomaron imágenes de los esferoides inmediatamente antes del tratamiento y 24 horas después del tratamiento.PRINCIPALES MEDIDAS DE RESULTADO:Los diámetros de los esferoides se midieron con ImageJ y se calculó el porcentaje medio de reducción de cada esferoide para determinar el efecto del tratamiento sobre el crecimiento de los esferoides. El análisis de varianza mediante comparaciones por pares se realizó con las pruebas de diferencia mínima significativa protegida de Fisher.RESULTADOS:Los grupos sin tratamiento (n =119 esferoides) y vehículo (n=126 esferoides) demostraron un aumento en el diámetro del esferoide durante el período de tratamiento. Por el contrario, los esferoides tratados con saquinavir (n =151 esferoides) demostraron una reducción porcentual estadísticamente significativa en comparación con los grupos sin tratamiento ( p < 0,0001) y con vehículo (p = 0,002).LIMITACIONES:una limitación de estos datos es que es probable que haya algún error humano dado que las imágenes fueron analizadas por tres científicos diferentes.CONCLUSIONES:Saquinavir conduce a una reducción porcentual estadísticamente significativa en el crecimiento de esferoides de tumores anales en ratones ex-vivo en comparación con los grupos de control. La terapia con inhibidores de la proteasa puede ser un tratamiento eficaz o una terapia adyuvante del protocolo Nigro para promover la regresión del tumor del cáncer anal. Consulte Video Resumen en http://links.lww.com/DCR/C82 . (Traducción-Dr. Felipe Bellolio ).


Asunto(s)
Antiinfecciosos , Neoplasias del Ano , Humanos , Ratones , Animales , Saquinavir/farmacología , Saquinavir/uso terapéutico , Virus del Papiloma Humano , Inhibidores de Proteasas , Ratones Transgénicos , Neoplasias del Ano/tratamiento farmacológico , Neoplasias del Ano/patología , Estudios Retrospectivos
6.
J Surg Res ; 282: 137-146, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36274448

RESUMEN

INTRODUCTION: Anal dysplasia and anal cancer are major health problems. This study seeks to determine if inhibition of mTOR and/or PI3K pathways is effective at anal cancer prevention in mice with/without established precancerous lesions of the anus (anal dysplasia). METHODS: K14E6/E7 mice were entered into the study at 5 wk, 15 wk, or 25 wk of age. Mice were treated with a topical carcinogen, 7,12-Dimethylbenz[a]anthracene (DMBA), which ensures carcinoma development within 20 wk. Treatment groups included: no treatment, DMBA only, topical Pictilisib (PI3K inhibitor) with/without DMBA, topical Sapanisertib (mTOR inhibitor) with/without DMBA, and topical Samotolisib (dual PI3K/mTOR inhibitor) with/without DMBA. Mice underwent weekly observations for anal tumor development (tumor-free survival). After 20 wk of treatment, anal tissue was harvested and evaluated histologically for squamous cell carcinoma (SqCC). RESULTS: All topical treatments in conjunction with DMBA increased tumor-free survival in mice that started treatment at 15 wk of age when compared to DMBA-only treatment, except for Pictilisib + DMBA in males. Topical Sapanisertib increased tumor-free survival in mice regardless of starting treatment age. When examining tissue for microscopic evidence of SqCC, only topical Samotolisib in males decreased SqCC in the 15 wk starting mice. CONCLUSIONS: Sapanisertib, the mTOR inhibitor, had the greatest effect, in terms of increasing tumor-free survival, regardless of starting time point or sex. Unlike the other treatments, Samotolisib, the dual PI3K/mTOR inhibitor, decreased microscopic evidence of SqCC when starting treatment at 15 wk of age but only in male mice.


Asunto(s)
Neoplasias del Ano , Carcinoma de Células Escamosas , Ratones , Masculino , Animales , Fosfatidilinositol 3-Quinasas , Inhibidores mTOR , Canal Anal/patología , 9,10-Dimetil-1,2-benzantraceno/farmacología , Neoplasias del Ano/prevención & control , Neoplasias del Ano/patología , Serina-Treonina Quinasas TOR/metabolismo , Carcinoma de Células Escamosas/patología
7.
Colorectal Dis ; 25(6): 1238-1247, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36945080

RESUMEN

AIM: Immunosuppressed patients are more likely to fail nonoperative management of acute diverticulitis and have more postoperative complications than the immunocompetent. Transplant recipients form a subcategory among the immunosuppressed with unique challenges. The aim of this work is to report 30-day postoperative complications after colectomy for acute diverticulitis and success rates of nonoperative management in pre- and post-transplant patients. METHOD: This is a retrospective cohort study at a single-institution tertiary referral centre. Patients with a history of acute diverticulitis were extracted from a database of 6152 recipients of solid-organ abdominal transplant between 2000 and 2015 and stratified by the index episode of diverticulitis: before or after solid-organ transplant surgery. Outcomes included 30-day postoperative complications and failure of nonoperative management. RESULTS: Acute diverticulitis occurred in 93 patients, 69 (74%) posttransplant. Postcolectomy complications were higher posttransplant than pretransplant (43% vs. 13%, p = 0.04). Posttransplant status was not an independent risk factor for complications (odds ratio 3.59, 95% CI 0.79-16.31) when adjusting for sex and surgical acuity. Immediate urgent colectomy (29% vs. 31%, p = 0.84) and failure of nonoperative management (7% vs. 9%, p = 0.82) were similar. Complications occurred equally in those requiring urgent colectomy after nonoperative management and those undergoing immediate urgent colectomy. CONCLUSION: Urgent colectomy rates are similar in solid-organ abdominal transplant recipients pre- and posttransplant. Posttransplant complication rates appear to be increased but transplant status as an independent factor is not significantly associated with an increased risk in this study cohort. These findings should be considered when counselling patients on the relative risks and benefits of surgical intervention for diverticulitis before versus after solid-organ transplantation.


Asunto(s)
Diverticulitis del Colon , Diverticulitis , Trasplante de Órganos , Humanos , Diverticulitis del Colon/cirugía , Diverticulitis del Colon/complicaciones , Estudios de Cohortes , Estudios Retrospectivos , Resultado del Tratamiento , Diverticulitis/complicaciones , Trasplante de Órganos/efectos adversos , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/etiología , Colectomía/efectos adversos
8.
Dysphagia ; 38(5): 1382-1397, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-36949296

RESUMEN

Early motor and non-motor signs of Parkinson disease (PD) include dysphagia, gastrointestinal dysmotility, and constipation. However, because these often manifest prior to formal diagnosis, the study of PD-related swallow and GI dysfunction in early stages is difficult. To overcome this limitation, we used the Pink1-/- rat, a well-established early-onset genetic rat model of PD to assay swallowing and GI motility deficits. Thirty male rats were tested at 4 months (Pink1-/- = 15, wildtype (WT) control = 15) and 6 months (Pink1-/- = 7, WT = 6) of age; analogous to early-stage PD in humans. Videofluoroscopy of rats ingesting a peanut-butter-barium mixture was used to measure mastication rate and oropharyngeal and pharyngoesophageal bolus speeds. Abnormal swallowing behaviors were also quantified. A second experiment tracked barium contents through the stomach, small intestine, caecum, and colon at hours 0-6 post-barium gavage. Number and weight of fecal emissions over 24 h were also collected. Compared to WTs, Pink1-/- rats showed slower mastication rates, slower pharyngoesophageal bolus speeds, and more abnormal swallowing behaviors. Pink1-/- rats demonstrated significantly delayed motility through the caecum and colon. Pink1-/- rats also had significantly lower fecal pellet count and higher fecal pellet weight after 24 h at 6 months of age. Results demonstrate that swallowing dysfunction occurs early in Pink1-/- rats. Delayed transit to the colon and constipation-like signs are also evident in this model. The presence of these early swallowing and GI deficits in Pink1-/- rats are analogous to those observed in human PD.


Asunto(s)
Trastornos de Deglución , Enfermedad de Parkinson , Ratas , Humanos , Masculino , Animales , Enfermedad de Parkinson/complicaciones , Deglución , Bario , Trastornos de Deglución/etiología , Estreñimiento/complicaciones
9.
Dysphagia ; 38(6): 1551-1567, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37195518

RESUMEN

BACKGROUND: Swallowing impairments resulting from stroke have few rehabilitative options. Prior evidence suggests lingual strengthening exercise may provide some benefit, but more randomized controlled trials are required. The purpose of this study was to examine efficacy of progressive lingual resistance training on lingual pressure generative capacity and swallowing outcomes for individuals with dysphagia after stroke. METHODS: Participants with dysphagia within 6 months of acute stroke were randomly assigned to: (1) treatment: progressive resistance tongue exercise using pressure sensors for 12 weeks with usual care; or (2) control: usual care only. Outcomes were measured at baseline, 8 and 12 weeks to assess group differences in lingual pressure generation, swallow safety, efficiency, oral intake, and swallowing quality of life. RESULTS: Final sample included 19 participants [treatment (N = 9) and control (N = 10)] with 16 males and 3 females (mean age = 69.33). Functional Oral Intake Scale (FOIS) scores improved significantly (p = 0.04) in the treatment group from baseline to 8 weeks compared to usual care (control). No significant differences between treatment groups were identified for other outcomes; large effect sizes were detected for group differences in lingual pressure generative capacity from baseline to 8 weeks at the anterior sensor (d = .95) and posterior sensor (d = 0.96), and vallecular residue of liquids (baseline to 8-week d = 1.2). CONCLUSIONS: Lingual strengthening exercise resulted in significant improvements in functional oral intake for patients with post-stroke dysphagia as compared to usual care after 8 weeks. Future studies should include a larger sample size and address treatment impact on specific aspects of swallow physiology.


Asunto(s)
Trastornos de Deglución , Accidente Cerebrovascular , Masculino , Femenino , Humanos , Anciano , Trastornos de Deglución/etiología , Trastornos de Deglución/terapia , Calidad de Vida , Resultado del Tratamiento , Accidente Cerebrovascular/complicaciones , Deglución , Lengua , Ensayos Clínicos Controlados Aleatorios como Asunto
10.
Am J Transplant ; 22(8): 2052-2063, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35593379

RESUMEN

Enteric drainage in pancreas transplantation is complicated by an enteric leak in 5%-8%, frequently necessitating pancreatectomy. Pancreatic salvage outcomes are not well studied. Risk factors for enteric leak were examined and outcomes of attempted graft salvage were compared to immediate pancreatectomy. Pancreas transplants performed between 1995 and 2018 were reviewed. Donor, recipient, and organ variables including demographics, donor type, ischemic time, kidney donor profile index, and pancreas donor risk index were analyzed. Among 1153 patients, 33 experienced enteric leaks (2.9%). Donors of allografts that developed leak were older (37.9y vs. 29.0y, p = .001), had higher KDPI (37% vs. 24%, p < .001), higher pancreas donor risk index (1.83 vs. 1.32, p < .001), and longer cold ischemic time (16.5 vs. 14.8 h, p = .03). Intra-abdominal abscess and higher blood loss decreased the chance of successful salvage. Enteric leak increased 6-month graft loss risk (HR 13.9[CI 8.5-22.9], p < .001). However, 50% (n = 12) of allografts undergoing attempted salvage survived long-term. After 6 months of pancreas graft survival, salvage and non-leak groups had similar 5-year graft survival (82.5% vs. 81.5%) and mortality (90.9% vs. 93.5%). Enteric leaks remain a challenging complication. Pancreatic allograft salvage can be attempted in suitable patients and accomplished in 50% of cases without significantly increased graft failure or mortality risk.


Asunto(s)
Trasplante de Riñón , Trasplante de Páncreas , Supervivencia de Injerto , Humanos , Trasplante de Riñón/efectos adversos , Trasplante de Páncreas/efectos adversos , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos
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