Trastornos electrolíticos inducidos por fármacos y sustancias tóxicas / Electrolyte disorders induced by drugs and toxic substances

Las enfermedades pueden generar un desequilibrio de electrolitos como parte de su fisiopatología, al igual que los medicamentos usados crónicamente y algunas sustancias tóxicas disponibles en nuestro medio. A pesar de todos los datos estadísticos existentes, la incidencia global de los trastornos electrolíticos secundarios a fármacos o sustancias tóxicas permanece desconocida, y, posiblemente, subregistrada; por lo tanto, el objetivo de esta revisión es analizar los trastornos electrolíticos que causan algunos medicamentos y sustancias tóxicas, y describir el mecanismo a través del cual se producen las alteraciones, en particular, del sodio, potasio, magnesio, calcio y fósforo, con el fin de alertar a los profesionales de la salud en el momento de enfrentarse a este tipo de condiciones en su práctica clínica. El conocimiento de los efectos adversos relacionados con medicamentos y tóxicos es importante para prevenir, identificar y gestionar de forma eficaz, complicaciones que son potencialmente peligrosas. Esta revisión pretende ser un referente de apoyo para los profesionales de la salud en estas situaciones

Diseases can generate an electrolyte imbalance as part of their pathophysiology, as well as chronic use of some medications, and toxic substances available in our environment. Despite all the separate statistical data, the overall incidence of fluid and electrolyte disorders secondary to drugs or toxic substances remains unknown, and possibly underreported; therefore, the objective of this review is to analyze electrolyte disorders caused by some medications and toxic substances, and describe the mechanism through which changes in sodium, potassium, magnesium, calcium and phosphorus occur, in particular, in order to alert health professionals when facing this type of conditions in their clinical practice. Knowledge of drug and toxic-related adverse effects is important to effectively prevent, identify, and manage complications that can be potentially life-threatening. This review intends to be a reference for supporting health professionals in these situations

Enfermedad de Nora: proliferación osteocondromatosa parostal atípica / Nora´s Disease: atypical parosteal osteochondromatous proliferation

La proliferación osteocondromatosa parostal atípica es una entidad muy inusual de los dedos de los pies y de las manos, y ocasionalmente, en otros sitos del esqueleto; es, igualmente, una entidad muy infrecuente en nuestro medio; este es el segundo caso reportado en el Instituto Nacional de Cancerología (INC) de Bogotá, Colombia, y hay menos de 100 casos en la literatura en inglés. Es una entidad a la que fácilmente se olvida o se desconoce, por su rareza, presenta un riesgo importante de error en la mayoría de los casos por sobrediagnóstico. En la actualidad se debate si esta dolencia es o no una verdadera neoplasia, debido al conocimiento más profundo de los mecanismos de condrogénesis y osteogénesis a escala molecular, y que bien podrían transformar la metodología y la nomenclatura del diagnóstico y las modalidades terapéuticas de las neoplasias osteoesqueléticas y de los tejidos blandos. En este trabajo se presenta un caso de enfermedad de Nora, junto con un sucinto resumen de la clínica, las imágenes y los hallazgos en patología quirúrgica, y con una discusión y una actualización sobre el estado del conocimiento de esta enfermedad.

Bizarre parosteal osteochondromatous proliferation is a rare disease of the toes and fingers; occasionally occurring at other sites in the skeleton. However, it is highly uncommon in our population: this case is only the second reported at the National Cancer Institute of Colombia, and there are fewer than 100 cases mentioned in the English language literature. In most cases, the risk of over-diagnosis is high. Debate currently centers on whether this ailment is a true neoplasia, in light of what little is known of its chondrogenesis and ossification at the molecular level-greater knowledge of which could transform the diagnostic methodology and nomenclature, as well as therapeutic approaches for the osteoskeletal neoplasia and soft tissues. We present a case of Nora´s disease, accompanied by a concise clinical summary with surgical pathology images and findings, along with a discussion on the current state of knowledge of this disease.

National trends in parathyroid surgery from 1998 to 2008: a decade of change.

BACKGROUND: The introduction of limited explorations (LE) for parathyroidectomy broadened the management possibilities for hyperparathyroidism. We sought to document this evolution of change in parathyroid surgery. STUDY DESIGN: Members of the American Association of Endocrine Surgeons and the American College of Surgeons were sent a 49-question survey, and 256 surgeons, accounting for 46% of parathyroid operations nationwide, responded. Associations derived from questionnaire data were tested for significance using chi-square and Kruskal-Wallis methods. RESULTS: Currently, 10% of surgeons practice bilateral neck exploration, 68% practice LE, and 22% have a mixed practice. Five years ago, these percentages were, respectively, 26%, 43%, and 31%; and 10 years ago they were 74%, 11%, and 15%. Shift to LE was greatest among endocrine surgeons, high-volume surgeons, and surgeons trained by mentors who practiced LE. A focal, single-gland examination under general anesthesia and 23-hour observation are preferred by most surgeons. Half of all general surgeons, in contrast to fewer than 10% of endocrine surgeons, never monitor parathyroid hormone intraoperatively, even with LE. Dramatic differences were apparent among subsets of surgeons in operative volumes, indications for bilateral neck exploration, followup care, expertise with ultrasound and sestamibi, and perceptions of cure and complication rates. Evidence-based literature and guidance from surgical societies had the greatest influence on the decision to practice LE. CONCLUSIONS: This survey formally documents the evolution of practice patterns in parathyroid surgery over the last decade. Although LE has achieved wide acceptance, surgical management of hyperparathyroidism has become increasingly disparate. This trend may highlight a need to define best-practice guidelines.

Unrecognized adrenal insufficiency in patients undergoing laparoscopic adrenalectomy.

BACKGROUND: Subclinical Cushing's syndrome (SCS) is a well-described phenomenon where abnormalities of the hypothalamic-pituitary-adrenal axis exist in the absence of overt signs and symptoms of classic Cushing's syndrome. While this has been shown to exist in 5-20% of patients with adrenal lesions, no standardized biochemical regimen exists to screen for SCS. Consequently, many of these patients may not be diagnosed prior to adrenalectomy with the risk of postoperative adrenal insufficiency. We began checking morning (a.m.) serum cortisol levels on postoperative day 1 (POD1) following unilateral adrenalectomy for nonfunctioning adrenal lesions to determine the incidence of unrecognized adrenal insufficiency (AI) in these patients. METHODS: One hundred and five patients undergoing adrenalectomy at a tertiary care center from 1999 to 2007 were retrospectively evaluated. Patients with Cushing's syndrome, conditions associate with bilateral disease, and those receiving perioperative steroids were excluded, leaving 41 patients for analysis. A.m. serum cortisol levels were obtained in all patients POD1. Multiple factors were analyzed as possible predictors of AI. Analysis of variance (ANOVA), t-test, and chi-square test were used to determine statistical significance. RESULTS: The 41 patients' diagnoses included 13 pheochromocytomas, 15 nonsecreting adenomas, 5 aldosteronomas, 5 metastatic lesions, 1 adrenocortical carcinoma, and 2 other benign lesions. Three groups were identified based on POD1, a.m. cortisol levels: sufficient (>10 microg/dl; n = 25, 61%), low-normal (3.4-10 microg/dl; n = 7, 17%), and insufficient (<3.4 microg/dl; n = 9, 22%). Tumor size and presence of diabetes, hypertension, and obesity were predictive of postoperative AI (p < 0.05). CONCLUSIONS: AI after unilateral adrenalectomy without evidence of cortisol hypersecretion on preoperative screening was present in a significant number of patients in our series. Patients with diabetes, hypertension, obesity, and larger tumors may be at higher risk for postoperative AI. More thorough screening for cortisol hypersecretion may be warranted in patients with these characteristics, and obtaining routine postoperative cortisol levels may avoid potentially dangerous unrecognized adrenal insufficiency following adrenalectomy.

Effectiveness of peripheral thyrotropin receptor mRNA in follow-up of differentiated thyroid cancer.

Thyroid cells in peripheral circulation have been linked to thyroid cancer (TC). These cells express thyrotropin receptor (TSHR) messenger RNA (mRNA), which has been studied as a marker of initial TC diagnosis. We examined the utility of TSHR mRNA in long-term follow-up of TC patients. From 2002 to 2007, TSHR mRNA was prospectively measured by quantitative reverse-transcription polymerase chain reaction (RT-PCR) from peripheral blood samples in 259 patients, and those followed > or =3 months since initial thyroidectomy were studied. TSHR mRNA levels were correlated to thyroglobulin (Tg), imaging studies, and disease status during follow-up. Thirty-four patients underwent 20 +/- 14 months median follow-up for papillary (n = 31, 91%), follicular (n = 2) or Hurthle cell (n = 1) TC. Advanced-stage disease occurred in 24% at presentation, and 11 (32%) developed cervical node metastases or recurrence requiring reoperation during follow-up. Of 52 simultaneous TSHR mRNA and serum Tg measurements, 52% were concordant. TSHR mRNA missed disease in 21% patients, but was better than Tg in 27%, including all those with Tg antibodies. TSHR mRNA concurred with whole-body scan detectable disease for 11/14 patients (79%) and accurately predicted overall TC disease status in 77% patients. In discordant cases, TC recurrence was apparent from other imaging modalities [positron emission tomography (PET) scan or ultrasound]. TSHR mRNA in conjunction with Tg diagnosed TC recurrence with 90% sensitivity and 94% specificity. We conclude that TSHR mRNA demonstrates high concordance rates with present methods of detecting TC recurrence, and appears to be more accurate in patients with Tg antibodies. As a novel adjunct, TSHR mRNA may enhance long-term management of TC patients.

Avoidable reoperations for thyroid and parathyroid surgery: effect of hospital volume.

BACKGROUND: Hospital volume for thyroid and parathyroid surgery inversely correlates with perioperative complications. This correlation has not been made regarding the need for reoperation. METHODS: We retrospectively analyzed 395 reoperative thyroid (TR) and parathyroid (PR) surgeries at a tertiary care hospital from 1999 to 2007. Based on current standards of care, reoperations were classified as avoidable or unavoidable. Public discharge data were used to classify hospitals as low-volume centers (LVC; <20 cases/yr) or high-volume centers (HVC; >/=20 cases/yr). The chi(2) test was used to determine statistical significance. RESULTS: Hospital data were available for 335 reoperations (85%). There were 134 avoidable (34%) and 201 unavoidable (66%) procedures. Primary hyperparathyroidism (HPT) and thyroid cancer each accounted for a third of cases. Of PR from LVC, 77% were avoidable compared with 22% from HVC (P < .001). Of TR from LVC, 50% were avoidable versus 14% from HVC (P < .001). Operations for both primary HPT and thyroid cancer led to avoidable reoperations more frequently if performed at a LVC (P < .001). CONCLUSION: By objective criteria, many thyroid and parathyroid reoperations are avoidable. Most originate from LVC. In addition to decreasing complication rates, thyroid and parathyroid surgery performed at HVC would decrease the need for patients to undergo reoperations.

Peripheral thyrotropin receptor mRNA as a novel marker for differentiated thyroid cancer diagnosis and surveillance.

Thyroid cancer is the most prevalent endocrine cancer whose incidence rates, particularly among women, have increased over the last decade. Although survival outcomes following surgery (with or without radioactive iodine ablation treatment) remain favorable, a significant proportion of patients are at lifetime risk of locoregional lymph node recurrence and distant metastasis. Serum thyroglobulin (Tg) has been the only circulating marker in routine use for detecting thyroid cancer recurrence, but it lacks sensitivity and is unreliable when Tg antibodies are present. New molecular markers for thyroid cancer have been investigated, with most based on detection in thyroid nodule or tumor tissue specimens. Recently, it has become possible to detect thyroid cancer cells in peripheral blood by measuring the mRNA of thyroid-specific genes, such as the mRNA of Tg and thyrotropin receptor. These have become promising new circulating markers for thyroid cancer. This review highlights the progress in this field from the perspective of improved initial cancer diagnosis and enhanced ability to monitor thyroid cancer recurrence.

Predicting the success of limited exploration for primary hyperparathyroidism using ultrasound, sestamibi, and intraoperative parathyroid hormone: analysis of 1158 cases.

OBJECTIVE: The aim of this study was to determine the success of limited neck exploration (LE) for primary hyperparathyroidism (1 degrees HPT). METHODS: Between 1999 and 2007, 1407 patients with hyperparathyroidism underwent bilateral neck exploration (BE). Of these, 1158 patients with first-time sporadic 1 degrees HPT were analyzed prospectively. Based on surgeon-performed ultrasound (US) and sestamibi scan (MIBI), LE was initially performed. Regardless of results, BE followed to identify the presence of additional parathyroid pathology. RESULTS: Of 1158 patients, 242 (21%) were found to require concomitant thyroid surgery thus excluding LE. Of the remaining 916 patients, a single abnormal gland was identified on MIBI in 682 (74%), US in 731 (80%), and concordance of both in 588 (64%). Unsuspected multiglandular disease (MGD) was identified at BE in 22%, 22%, and 20% of patients, respectively. Adding intraoperative parathyroid hormone sampling (IOPTH) further reduced the rate of unsuspected MGD to 16%, 17%, and 16%. Overall, IOPTH correctly predicted MGD in only 22%. Neither concomitant nonsurgical thyroid disease nor more stringent selection criteria (preop Ca>11 mg/dL and PTH>120 pg/dL) altered success rates. In patients with MGD, a subsequent gland identified was larger than the index gland in 23%. Ninety-eight percent of BE patients were cured of 1 degrees HPT. CONCLUSIONS: This is the largest study to evaluate the prevalence of additional parathyroid pathology in patients who are candidates for LE. Limitations in localizing studies and IOPTH fail to identify MGD in at least 16% of patients, risking future recurrence.

Análisis de longitud telométrica en carcinogénesis gástrica / Telomere lenght analysis in gastric carcinogenesis

Antecedentes: El modelo de carcinogénesis gástrica de múltiples pasos implica alteraciones genéticas y epigenéticas pobremente definidas. Una de estas alteraciones conocida como disfunción telomérica ha sido propuesta como uno de los principales mecanismos generadores de la inestabilidad genética encontrada desde las etapas más tempranas en varios cánceres epiteliales, incluido el adenocarcinoma gástrico. Métodos: En el presente estudio, analizamos la longitud telomérica media (LTM) en tejidos gástricos tumorales y no tumorales, así como en condiciones precancerosas tales como gastritis atrófica, metaplasia y displasia, a partir de tejido fresco empleando las metodologías de Southern blot y Dot blot, con base en protocolos previamente descritos. Resultados: Se encontró una buena correlación entre los valores obtenidos para la LTM usando estas dos metodologías (r2: 0,84). No encontramos diferencias estadísticamente significativas en la LTM entre las muestras tumorales y no tumorales (9,38±3,2 Kb y 8,86±0,32 Kb, respectivamente, P: 0,53), tampoco encontramos una correlación significativa entre la LTM y variables tales como la edad, sexo, localización ó diagnostico histopatológico. Conclusiones: Aunque no se encontraron diferencias en la LTM en esta muestra de cáncer gástrico originaria de la población colombiana, es posible que la implementación en una muestra de mayor tamaño de otras metodologías moleculares más sensibles, tales como el Q-FISH y la PCR en tiempo real, permitan identificar diferencias en la longitud telomérica más pequeñas o específicas de cromosomas en cáncer gástrico (AU)

Introduction: Gastric cancer is the second most common cancer worldwide and the leading cause of cancer deaths in Colombia. Despite identification of some environmental and genetic risk factors, little is known about molecular mechanisms of gastric carcinogenesis. Recently, telomere instability has been suggested as a key factor in epithelial cancers including gastric cancer. Materials and Methods: In the current study mean telomere length (MTL) in tumoral and non tumoral tissues, as well as precancerous conditions such as atrophic gastritis, metaplasia and dysplasia were analyzed. Samples were obtained from endoscopy and gastric resection surgery procedures in different health institutions in Bogotá, Colombia. Genomic DNA was isolated from 57 tissue samples corresponding to 23 tumors, 1 dysplasia, 4 metaplasias, 6 atrophic gastritis, and 23 non tumoral tissues. The MTL was measured using Southern blot and Dot blot methodologies, as previously described. Results: A good correlation between values obtained using these both techniques (r2: 0.84) was found. No statistically significant differences in MTL between tumoral and non tumoral samples ( 9.38±3.2 Kb and 8.86±0.32 Kb, respectively, P: 0.53)were found. Also no any significant correlation among MTL and variables such as age, sex, localization or histopathological diagnoses was appreciated. Conclusions: Although differences in TLM in the studied gastric cancer samples from Colombian population were not found, it is possible that in larger patient series and using more sensitive complementary molecular analytical techniques such as Q-FISH and qPCR, smaller or chromosome specific telomere differences could be identified (AU)

Casos de rinoescleroma y sífilis nasal tratados con radioterapia (1935) / Rhinoescleroma and nasal syphilis cases treated with radiotherapy (1935)

Se trata de un grupo de pacientes, todas ellas mujeres jóvenes provenientes del área rural con rinoscleroma. La revisión plantea un problema que setenta años después sigue perfectamente vigente, haciendo referencia a la similitud de presentación clínca, complicaciones e imágenes tanto radiológicas como histológicas que puede haber entre tumores, enfermedades inflamatorias e infecciosas, donde el diagnóstico final dependerá de la perfección de la aplicación de múltiples disciplinas. El rinoscleroma refleja claramente el paso por distintas clasificaciones y orígnes etiólogicos, descrito por primera vez en la sociedad médica de Viena, en 1870, por Von Hebra y Kaposi, como una forma de sarcoma entre de origen glial y carcinoma, posteriormente la misma sociedad lo consideró una forma de sífilis. En 1840, Biercowsky y Kraskow habían demostrado la enfermedad en restos arqueológicos de Terracota y de la cultura maya, correspondientes a 300-600 años antes de Cristo. En 1872 y 1877, Mikuliez y Gerber describieron las primeras imágeneshistológicas; en 1882,Frisch aisló un germen que consideró el agente causal del rinoscleroma. Sin embargo, esto no puede demostrar hasta 1962, cien años después de la priemera descripción, cuando Steffen, Smith y Hoffman aislaron un germen que cumplía la totalidad de los postulados de Koch, llamado klebsiella rhinoscleromatis (1,5)reconocido, en su cápsulas tipo III y IV, por técnicas de fermetacio´n, inmunológicas, biología molecular, cultivos con subespecialización bioquímica e inmunoperoxidasa (2,3)

Sarcoma alveolar de partes blandas: reporte de caso y casuistica en el Instituto Nacional de Cancerología, Colombia / Alveolar soft-tissue sarcoma

El sarcoma alveolar de partes blandas es una neoplasia y enigmática, cuya histogénesis es controversial.Se analiza un caso con la imagen característica histológico de cristales intracitoplasmáticos y se revisan casos diagnosticados en el Instituto Nacional de Cancerología entre 1996 y 2003 con énfasis en las características morfológicas e inmunofenotípicas.

Lesion Lítica expansiva de húmero proximal, quiste óseo aneurismático versus osteosarcoma / Lythic lesion of the proximal humerus

Se presenta el caso de una niña de 5 años con una gran masa en el brazo izquierdo. La radiografía simple de húmero mostró una imagen lítica en el tercio proximal, interpretada como un quiste óseo aneurismático versus un osteosarcoma telangiectásica. Se describen las características de las imágenes y el cuadro histológico del tumor, haciendo énfasis en el diagnóstico diferencial.

Evaluacion de factores pronosticos en pacientes con melanoma maligno de piel: analisis multifactorial / Evaluation of prognosis factors in patients with malignant skin melanoma: multifactorial analysis

Considerando que el melanoma maligno por su comportamiento biologico facilita la aplicacion de diversos parametros clinicos y patologicos, realizamos el presente trabajo para determinar el pronostico de los pacientes que acudieron a la consulta de melanomas del Instituto Nacional de Cancerologia entre 1977 y 1982. 77 pacientes fueron admitidos por presentar la lesion en piel, seguir un protocolo de manejo y un adecuado estudio sistologico. Se tuvieron en cuenta 40 variables y se elaboraron por medio de un sistema computarizado las caracteristicas de la muestra, la formacion de curvas de sobrevida por el metodo de Kaplan y Meier (27) y la identificacion de los factores de importancia pronostica por medio del analisis multifactorial segun Cox (12). Ademas se practico un calculo de regresion multifactorial que permitio obtener la ecuacion para estimar la probabilidad de sobrevivir 5 anos para cada uno de los pacientes. Las variables de mayor significado pronostico fueron: presencia de metastasis, ulceracion, micrometria de Breslow, clasificacion de Clark, micrometria modificada y hallazgo de celulas tumorales en el vaciamiento. Todo lo anterior nos permite concluir que ante una lesion tan agresiva se requieren campanas de educacion a la comunidad para lograr que los pacientes consulten oportunamente, lo cual repercutiria en un diagnostico mas temprano y ademas son necesarios nuevos estudios de investigacion para entender la caprichosa evolucion de las celulas melanociticas. Como un hecho practico es importante recalcar la incapacidad de los vaciamientos...