Factores tempranos asociados a apendicectomía negativa / Early factors associated with negative appendectomy

Objetivo: analizar características predictoras de apendicectomía negativa (AN) en una cohorte de pacientes llevados a cirugía durante el año 2018 en una institución de salud de alta complejidad de la ciudad de Medellín, Colombia. Materiales y Métodos: seguimiento retrospectivo a una cohorte basada en registros médicos. Se analizaron pacientes adultos sometidos a apendicectomía. Se estimó la tasa de AN y se describieron características clínicas, paraclínicas y sociodemográficas. Se analizaron predictores de AN mediante el modelo lineal generalizado familia binomial, enlace logarítmico. Se presentan razones de riesgo (RR) observadas y ajustadas junto con intervalos de confianza del 95% (IC95%). Para el modelo multivariado se estimó el área bajo la curva del operador receptor (ROC). Resultados: la tasa de AN fue de 5,2%. No se solicitó tomografía computarizada (TC) de abdomen en el 48,9% de los casos, 4,1% de los pacientes presentaron disuria. Entre los factores estudiados, la disuria, no solicitud de TC, edad y leucocitosis, se asociaron significativamente con mayor riesgo de AN. Resaltan particularmente los pacientes que presentaron disuria y no les fue solicitado TC, en quienes el riesgo ajustado de AN fue de 30,3% (RR = 17,31; IC95% 5,00 ­ 59,87). ROC fue 0,834. Conclusiones: los pacientes llevados a cirugía sin TC y que se presentaron con disuria, particularmente los de mayor edad, concentraron el mayor riesgo de AN. Considerar estas características al definir el manejo quirúrgico del paciente con sospecha de apendicitis aguda, puede contribuir a disminuir las AN..(Au)

Objective: to analyze predictive characteristics of negative appendectomy (NA) in a cohort of patients who underwent surgery during 2018 in a high complexity healthcare institution in the city of Medellín, Colombia. Materials and Methods: retrospective follow-up to a cohort of adult patients who underwent appendectomy. The rate of NA was estimated and the clinical, paraclinical and sociodemographic characteristics were described. The analysis of predictors of NA was carried out using the generalized linear model binomial family, logarithmic link. Observed and adjusted risk ratios (RR) are presented along with 95% confidence intervals (95% CI). For the multivariate model, the area under the receiver operator curve (ROC) was estimated. Results: the NA rate was 5.2%. Abdominal computed tomography (CT) was not requested in 48.9% of the cases, 4.1% of the patients had dysuria. Among the factors studied, dysuria, nonrequest for CT, age and leukocytosis were significantly associated with a higher risk of NA. Is worth noting that the adjusted risk of NA of the patients who presented with dysuria and those in which no CT was requested, was 30.3% (RR = 17.31; 95% CI 5.00 - 59.87). ROC was 0.834. Conclusions: patients who underwent surgery without CT and presented with dysuria, particularly the older ones, had the highest risk of NA. Considering these characteristics when defining the surgical management of patients with suspected acute appendicitis can help reduce NA..(Au)

Desprendimiento seroso de retina agudo inducido por cirugía en posición prono / Acute serous detachment of retina after surgery in prone position

Resumen La posición en decúbito prono es utilizada en cirugía para acceder a diferentes estructuras anatómicas del paciente. Esta posición puede asociarse a pérdida visual postoperatoria en el 0,05 a 1 % de las complicaciones reportadas. El desprendimiento seroso de retina es la separación de la retina neurosensorial del epitelio pigmentario de la retina por acumulación de líquido, sin daño estructural, como resultado de cambios en la permeabilidad y perfusión de la coroides. Se presenta el caso de una mujer con indicación de extracción de prótesis glútea bilateral mediante cirugía en decúbito prono. Se identificó un desplazamiento del cojín posicionado en la cara y la cabecera no correspondía con la estructura ósea de la paciente. En sala de recuperación la paciente refirió pérdida visual en ojo izquierdo, por lo cual fue evaluada inmediatamente por Oftalmología encontrando una presión intraocular bilateral normal; un examen de fondo de ojo izquierdo evidenció múltiples áreas de desprendimiento de la retina. La tomografía con coherencia óptica confirmó la presencia de fluido subretiniano. Fue tratada con nepafenaco y prednisolona tópicas y evaluada a las 72 horas y a la semana, con resolución total del cuadro y agudeza visual corregida de 20/20. No existen reportes en la literatura de desprendimiento seroso de retina posterior a cirugía en prono. Al evaluar el caso se asumió que la incorrecta posición del cojín y el tamaño inadecuado de la cabecera fueron factores que podrían haber contribuido a estasis venoso del flujo coroideo aumentando súbitamente la presión hidrostática en la coroides, lo que provocó el desprendimiento seroso de retina.

Abstract Prone position is used in surgery to access different anatomical structures of the patient. This position can be associated with postoperative visual loss in 0.05 to 1 % of complications. Serous retinal detachment is the separation of the neurosensory retina from the retinal pigment epithelium by fluid accumulation without structural damage. This is the result of changes in the permeability and perfusion of the choroid. This is the case of a woman with an indication for removal of a bilateral gluteal prosthesis by surgery in the prone position. A displacement of the cushion positioned on the face was identified and the headboard did not correspond to the bone structure of the patient. In the recovery room, the patient reported visual loss in the left eye, which was immediately evaluated by Ophthalmology, finding a normal bilateral intraocular pressure. The left eye fundus examination revealed multiple areas of retinal detachment. Optical coherence tomography confirmed the presence of subretinal fluid. She was treated with topical nepafenac and prednisolone, and evaluated at 72 hours and a week, with total resolution of the condition and corrected visual acuity of 20/20. There are no reports in the literature of serous retinal detachment after prone surgery. When evaluating the case, it was assumed that the incorrect position of the cushion and the inadequate size of the bedside are factors that could have contributed to venous stasis of the choroidal flow, suddenly increasing the hydrostatic pressure in the choroid that caused the serous retinal detachment.

Discovery of factors linked to antimony resistance in Leishmania panamensis through differential proteome analysis.

The rate of treatment failure to antileishmanial chemotherapy in Latin America is up to 64%. Parasite drug resistance contributes to an unknown proportion of treatment failures. Identification of clinically relevant molecular mechanisms responsible for parasite drug resistance is critical to the conservation of available drugs and to the discovery of novel targets to reverse the resistant phenotype. We conducted comparative proteomic-based analysis of Leishmania (Viannia) panamensis lines selected in vitro for resistance to trivalent antimony (Sb(III)) to identify factors associated with antimony resistance. Using 2-dimensional gel electrophoresis, two distinct sub-proteomes (soluble in NP-40/urea and Triton X-114, respectively) of promastigotes of WT and Sb(III)-resistant lines were generated. Overall, 9 differentially expressed putative Sb-resistance factors were detected and identified by mass spectrometry. These constituted two major groups: (a) proteins involved in general stress responses and (b) proteins with highly specific metabolic and transport functions, potentially directly contributing to the Sb-resistance mechanism. Notably, the sulfur amino acid-metabolizing enzymes S-adenosylmethionine synthetase (SAMS) and S-adenosylhomocysteine hydrolase (SAHH) were over-expressed in Sb(III)-resistant lines and Sb(III)-resistant clinical isolates. These enzymes play a central role in the upstream synthesis of precursors of trypanothione, a key molecule involved in Sb-resistance in Leishmania parasites, and suggest involvement of epigenetic regulation in response to drug exposure. These data re-enforce the importance of thiol metabolism in Leishmania Sb resistance, reveal previously unrecognized steps in the mechanism(s) of Sb tolerance, and suggest a cross-talk between drug resistance, metabolism and virulence.

Identification of developmentally-regulated proteins in Leishmania panamensis by proteome profiling of promastigotes and axenic amastigotes.

We have employed proteomics to identify proteins upregulated in the amastigote life-stage of Leishmaniapanamensis, using axenically-differentiated forms as models of authentic intracellular parasites. Resolution of the soluble proteomes of axenic amastigotes and promastigotes by two-dimensional electrophoresis (2DE) in the neutral pI range (5-7) revealed equivalent numbers of protein spots in both life-stages (644-682 using Coomassie Blue and 851-863 by silver staining). Although representing a relatively low proportion (8.1-10.8%) of the predicted 8000 gene products of Leishmania, these proteome maps enabled the reproducible detection of 75 differentially-regulated protein spots in amastigotes, comprising 24 spots "uniquely" expressed in this life-stage and 51 over-expressed by 1.2-5.7-fold compared to promastigotes. Of the 11 amastigote-specific spots analysed by mass spectrometry (MS), 5 yielded peptide sequences with no orthologues in Leishmania major, and the remaining 6 were identified as 7 distinct proteins (some of which were truncated isoforms) representing several functional classes: carbohydrate/energy metabolism (fructose 1,6-bisphosphate aldolase, glucose 6-phosphate dehydrogenase, pyruvate dehydrogenase), stress response (heat shock protein [HSP] 83), cell membrane/cytoskeleton (beta-tubulin), amino acid metabolism (cysteine synthase) and cell-cycle (ran-binding protein). Four additional over-expressed spots were tentatively identified as HSPs 60 and 70 and HSP 70-related proteins -1 and -4 by positional analogy with these landmark proteins in the Leishmania guyanensis proteome. Our data demonstrate the feasibility of proteomics as an approach to identify novel developmentally-regulated proteins linked to Leishmania differentiation and intracellular survival, while simultaneously pinpointing therapeutic targets. In particular, the amastigote-specific expression of cysteine synthase underlines the importance of de novo cysteine synthesis both as a potential parasite virulence factor and as a major metabolic difference from mammalian host cells.