Reacciones adversas poco comunes a antibióticos: Agranulocitosis por vancomicina / Rare adverse reactions to antibiotics: Vancomycin induced agranulocytosis

Las discrasias hemáticas inducidas por fármacos, son causadas por la interacción de diferentes fármacos con las células hematopoyéticas por medio de receptores específicos. Otros mecanismos fisiopatológicos pueden ser por toxicidad directa sobre la médula ósea o las células periféricas, por hipersensibilidad, por defectos inmunológicos secundarios a infecciones virales, por mecanismos mixtos o desconocidos. Las primeras asociaciones se describieron en la década de los años treinta. Los fármacos con mayor riesgo relativo de agranulocitosis o anemia aplásica son los antitiroideos, carbamazepina, las sulfonilureas, la indometacina, el piroxicam, entre otros. Se presentaa continuación el reporte de un caso clínico en paciente adulto quien con la administración de vancomicina presento agranulocitosis resolviendo el cuadro posterior a su suspensión.

The drug-induced blood dyscrasias are caused by the interaction of different drugs with the hematopoietic cells through specific receptors. Other pathophysiologic mechanisms may be by direct toxicity to bone marrow or peripheral cells, hypersensitivity, immunological defects secondary to viral infections, mixed or unknown mechanisms. The first associations were described in the thirties. Drugs with higher relative risk of a granulocytosis or aplastic anemia are antithyroid, carbamazepine, sulfonylurea, indomethacin and piroxicam among others. The report of a clinical case in an adult patient who after the administration of vancomycin presented agranulocytosis with resolution of the clinical picture after its suspension, is presented.

[Paraneoplastic dermatomyositis as a clue to occult gallbladder carcinoma]. / Dermatomiositis paraneoplásica como clave de un carcinoma de vesícula biliar oculto.

Adult-onset dermatomyositis (DM) is an idiopathic inflam- matory myopathy frequently associated with underlying cancer, including gastrointestinal tumors. However, its as- sociation with carcinomas of the hepatobiliary tract is exceptional. We present a case of paraneoplastic DM occurring as the first and only clinical manifestation of an underlying carcinoma of gallbladder.

[Food habits and winter diet of Charadrius melodus (Charadriiformes: Charadriidae) in Boca Ciega, Tamaulipas, Mexico]. / Hábitos alimenticios y dieta invernal de Charadrius melodus (Charadriiformes: Charadriidae) en Boca Ciega, Tamaulipas, México.

The Piping Plover (Charadrius melodus) is a migratory endangered species that arrives, along with a great number of other winter migratory birds, to Boca Ciega every year. In spite of the importance of this ecosystem, these species, are threatened by the current habitat change caused by the dredging activities in the area. With the aim to generate new information about the importance of this area during winter, we studied C melodus activities during the winter season in Laguna Madre, from December 2009 to March 2010. Our objectives were: 1) determine the importance of the area during winter, 2) describe C. melodus ethology, feeding substrate preferences and food items, 3) to analyze and describe the sympatric diversity associated with C melodus. A total of ninety nine individuals were observed during the monitoring. The Cochran and Kendall test showed a high significance of the species with the substrate and signs tests using a binomial distribution that indicated a high preference for algal type of substrate. The highest activity recorded for this species during this winter season was feeding. The principal food items found in sediments were larvae of Diptera: Chironomidae and Ephydridae. The sympatric species of C. melodus were two families of Charadriiforms: Scolopacidae (nine species) and Charadriidae (two species). We concluded that this is an important area for feeding, protection and rest sites for this species, and its protection and management is recommended.

Hábitos alimenticios y dieta invernal de Charadrius melodus (Charadriiformes: Charadriidae) en Boca Ciega, Tamaulipas, México / Food habits and winter diet of Charadrius melodus (Charadriiformes: Charadriidae) in Boca Ciega, Tamaulipas, Mexico

The Piping Plover (Charadrius melodus) is a migratory endangered species that arrives, along with a great number of other winter migratory birds, to Boca Ciega every year. In spite of the importance of this ecosystem, these species, are threatened by the current habitat change caused by the dredging activities in the area. With the aim to generate new information about the importance of this area during winter, we studied C. melodus activities during the winter season in Laguna Madre, from December 2009 to March 2010. Our objectives were: 1) determine the importance of the area during winter, 2) describe C. melodus ethology, feeding substrate preferences and food items, 3) to analyze and describe the sympatric diversity associated with C. melodus. A total of ninety nine individuals were observed during the monitoring. The Cochran and Kendall test showed a high significance of the species with the substrate and signs tests using a binomial distribution that indicated a high preference for algal type of substrate. The highest activity recorded for this species during this winter season was feeding. The principal food items found in sediments were larvae of Diptera: Chironomidae and Ephydridae. The sympatric species of C. melodus were two families of Charadriiforms: Scolopacidae (nine species) and Charadriidae (two species). We concluded that this is an important area for feeding, protection and rest sites for this species, and its protection and management is recommended.

Charadrius melodus es una especie migratoria en peligro de extinción. Cada año, la Laguna Madre recibe aves migratorias invernales, incluyendo a la especie antes mencionada, sin embargo su estabilidad se encuentra amenazada por el cambio de hábitat ocasionado por el dragado que se está realizando en la zona. La falta de estudios sobre C. melodus durante el invierno en la Laguna Madre, motivó la realización del trabajo (diciembre 2009-marzo 2010). Los objetivos fueron: 1) determinar la importancia del área invernal, 2) describir la etología y preferencias de sustrato en la alimentación, 3) analizar ítems alimenticios potenciales y describir la diversidad simpátrica asociadas a C. melodus. Se observaron 99 individuos durante el muestreo. Las pruebas de Cochran y Kendall presentaron una alta significancia de la especie con un tipo de sustrato y las pruebas de signos utilizando una distribución binomial indicaron que existe una alta preferencia hacia un tipo de sustrato. La mayor actividad registrada durante el periodo de muestreo fue la de alimentación. Los recursos alimenticios encontrados en las muestras de sedimentos fueron larvas de Dípteros. Las especies simpátricas a C. melodus pertenecen al orden Charadriiformes con dos familias: Charadriidae nueve especies y Scolopacidae dos especies. Por la importancia de la zona, se recomienda proteger Boca Ciega, pues representa sitios de alimentación, protección y descanso para el Chorlo melódico.

Cardiopatía dilatada en ataxia de Friedreich: el punto sin retorno / Dilated cardiomyopathy in Friedreich's ataxia: point of no return

Las cardiopatías infiltrativas se caracterizan por el depósito de sustancias en el miocardio que causan un impacto negativo en la arquitectura de la pared ventricular. La ataxia espino-cerebelosa de Friedreich es una enfermedad degenerativa, heredada, con carácter autosómico recesivo. Clínicamente se caracteriza por ataxia de extremidades y tronco, hiporreflexia, neuropatía periférica, retinopatía y cardiopatía, entre otros. La afectación cardíaca es muy frecuente y se detectan alteraciones en estudios pos-mortem en 95% a 100% de los pacientes. La tasa de mortalidad es elevada y se considera una enfermedad incurable, a pesar de la existencia actual de múltiples medicamentos en estudio basados en los fundamentos fisiopatológicos de esta afección.

Infiltrative heart diseases are characterized by deposit of substances in the myocardium that cause a negative impact on the architecture of the ventricular wall. Friedreich's spino-cerebellar ataxia is a degenerative disease, inherited in an autosomal recessive pattern. Clinically it is characterized by limb and trunk ataxia, hyporeflexia, peripheral neuropathy, retinopathy and heart disease among others. Cardiac involvement is common and on post-mortem studies cardiac abnormalities are found in 95% to 100% of patients. The mortality rate is high and it is considered an incurable disease, despite the current existence of multiple medications being studied, based on the pathophysiological basis of this condition.

Effect of lithium carbonate on subchondral bone in sexually mature Wistar rats.

Clinical and experimental studies have shown that lithium carbonate causes a number of clinical manifestations such as hyperparathyroidism, hypothyroidism, renal toxicity, and diabetes insipidus. The effect of this drug on the bone biology of experimental animals has not been studied to date. Therefore, the aim of the present experimental work was to study the effect of lithium on bone tissue in healthy sexually mature Wistar rats. Ten female Wistar rats, aged 312-412 months, 210-220 g body weight, were assigned to one of the following groups: untreated control group and experimental group receiving 45 mg/kg body weight/day of lithium carbonate in their drinking water during 3 months. Prior to euthanasia, blood samples were obtained in order to determine plasma phosphorus, calcium alkaline phosphatase, and lithium. After sacrifice, the tibiae were resected, processed, and embedded in paraffin. The following histomorphometric parameters were determined on digital photographs of the histologic sections: BV/TV (%), bone volume; Tb.Th (microm), trabecular thickness; Tb.N (mm(-2)/mm), trabecular number; Tb.Sp (microm), trabecular separation; Ob.S/BS (%), osteoblast surface; ES/BS (%), total erosive surface; Lc.S (%), lining cells surface; and GPC.Th (microm), thickness of growth plate cartilage. The results showed that administration of lithium carbonate cause bone loss in healthy sexually mature Wistar rats. Although the mechanism involved in bone toxicity remains to be clarified, the results obtained in the present study suggest that patients under long-term lithium therapy should be thoroughly evaluated, particularly those presenting other risk factors of osteopenia, such as menopause, low calcium intake, alcohol consumption, and glucocorticoid therapy.

Effect of topical administration of monosodium olpadronate on experimental periodontitis in rats.

BACKGROUND: Periodontitis is characterized by gingival inflammation, periodontal pocket formation, and bacterial plaque that lead to alveolar bone destruction. Research studies have recently begun to evaluate the effect of antiresorptive agents using experimental models of periodontitis. Bisphosphonates are the most frequently tested antiresorptive agents; their main effect is inhibition of bone resorption. The aim of this study was to perform a histomorphometric evaluation of the preventive effect of monosodium olpadronate (OPD), an aminobisphosphonate, on experimental periodontitis (EP). METHODS: Twenty male Wistar rats were used in this experiment. The animals were assigned to one of two groups: group I: EP; and group II: EP plus topical administration of OPD (EP + OPD). The contralateral side in both groups served as untreated controls (CI and CII), respectively. Mesio-distally oriented sections of each lower first molar were obtained for histomorphometric evaluation. RESULTS: The treated group (EP + OPD) exhibited marked inhibition of bone loss; interradicular bone volume was significantly greater than that observed in the EP group. The height of the periodontal ligament in the interradicular alveolar bone, which served as an indirect measure of bone loss, was found to be significantly increased in the EP group as compared to the EP + OPD group. Osteoclasts in the OPD treated group were detached from the bone surface, were round in shape, and exhibited a loss of polarity and lack of ruffled borders. CONCLUSIONS: The dose used herein was found to inhibit bone loss and to cause marked morphologic changes in osteoclasts. The drug effectively prevented bone loss caused by periodontitis.

The kidney transplant experience at Hospital de Especialidades, Centro Médico Nacional de Occidente, IMSS, Guadalajara México.

A total of 1,356 kidney transplants has been performed in the Hospital de Especialidades del Centro Médico Nacional de Occidente, IMSS, in Guadalajara Mexico, including 935 in the past 8 years. This represents an important increase of this activity in our country. Of the total transplants, 1,218 (90%) were from living donors and only 138 (10%) were from cadaveric donors, a number that we hope to increase. Most recipients were young adults, with an average age of 31 years old. The overall one-year graft and patient survival rates for living-donor kidney recipients were 90% and 82%, and for cadaveric kidney recipients they were 80% and 70%, respectively. Acute rejections occurred in 17% and chronic allograft nephropathy was diagnosed in 7% of our kidney transplant recipients. The main cause of patient death was infection, frequently invasive CMV. Cardiovascular complications were a relatively infrequent cause of death as has been seen in other international series. Hepatitis B and C have been widley studied. Hepatitis C is the most prevalent viral infection in our population. Both living and cadaveric donors in our series were young, which may explain the good results. We have had very few complications among living donors and no mortality. Two donors developed chronic renal insufficiency after the kidney donation (0.001%). This excellent safety record reflects the experience of our team. We hope to increase the number of cadaveric transplant donors with the renewed interest in enlarging the transplantation programs in Mexico while maintaining our high percentage of living donors in order to benefit more patients.

Leiomiosarcoma colorrectal: reporte de dos casos / Colorectal leiomyosarcoma: report of two cases

Casi todos los sarcomas colorrectales son leiomiosarcomas, que se originan en las células del músculo liso de la pared intestinal. Los síntomas de presentación y los hallazgos endoscópicos no son específicos, por lo que se requiere exploración quirúrgica para su diagnóstico. La resección completa es posible en el 50 a 60 por ciento de los casos. Las metástasis a la cavidad peritoneal e hígado son comunes. Sólo en 10 a 20 por ciento de los casos en quienes se practica resección completa presentan curación. Los pacientes con tumores de grado bajo de malignidad presentan una mayor supervivencia. A pesar de que los rangos de curación son bajos, la resección radical es un buen método paliativo. Ni la radioterapia ni la quimioterapia han mostrado ser efectivas como terapias adyuvantes. El papel de la resección preservadora de esfínteres y la excisión local en sarcomas rectales no es claro. El tratamiento convencional de las lesiones del tercio medio e inferior del recto es la resección abdominoperineal. En los tumores del colon, la resección segmentaria está indicada. La excisión local se fundamenta en la baja incidencia de metástasis a ganglios linfáticos locales en sarcomas colorrectales, pero la mayoría de los datos existentes sugieren que los rangos de recurrencia con excisión local son altos. Se presentan dos casos de pacientes masculinos atendidos en la Unidad de Coloproctología del Hospital General de México, los cuales presentaron rectorragia, pérdida de peso y marcadores inmunohistoquímicos positivos, con diagnóstico definitivo de leiomiosarcoma. La resección abdominoperineal para leiomiosarcoma del recto y la sigmoidectomía para leiomiosarcoma de sigmoides fueron los tratamientos quirúrgicos.Palabras clave: Leimiosarcoma colorrectal.

Alteraciones del ciclo menstrual en internas y residentes / Menstrual cycle charges in interns and residents

Determinar la incidencia de trastornos menstruales en internas y residentes asistenciales y de posgrado. Se entrevistaron las médicas utilizando un cuestionario elaborado para tal efecto. Hospital de la ciudad de Maracaibo tipo 3 y 2. Se analizaron 207 cuestionarios (87,7 por ciento) de 236 entrevistas: 172 (83,1 por ciento) residentes y 41 (16,9 por ciento) internas. Cincuenta y seis casos (27,15 por ciento) presentaron trastornos menstruales. La alteración del ciclo menstrual más frecuente fue el acortamiento de los mismos. El hospital, tipo de especialidad y año de residencia no tuvieron influencia. Las causas psíquicas fueron las que ocasionaron mayor número de alteraciones menstruales (84,5 por ciento) y al ser comparadas con causas de otro origen (15,5 por ciento) se encontró diferencia estadísticamente significativa (p=0,003). Las guardias fueron referidas como la causa más frecuente de irregularidad del ciclo (22,7 por ciento). Las médicas representan un grupo poblacional de alto riesgo a presentar alteraciones en el ciclo menstrual por su exposición a estrés psíquico

Valoración de la probabilidad de muerte del paciente traumatizado / Evaluation of death probability in traumatized patients

Se realizó un estudio retrospectivo con la finalidad de valorar las condiciones de ingreso de los pacientes traumatizados, y al mismo tiempo conocer la probabilidad de fallecer de cada uno de ellos. El estudio comprendió un periodo de 12 meses e incluyó 156 pacientes. Se obtuvieron los valores de la escala de trauma, basados en la escala abreviada de lesiones y la calibración del índice de severidad de lesiones. Se utilizó el método del índice revisado de la severidad del trauma para calcular la probabilidad de muerte de cada paciente. Con este método se encontró que los sujetos fallecidos tenían una probabilidad de morir mayor del 50 por ciento; sin embargo, 29 pacientes con la misma probabilidad sobrevivieron. Se concluye que los índices para valorar la severidad del trauma son útiles para la comprensión de la epidemiología y valoración de la calidad de atención del truma. Se enfatizan los lineamientos generales de la primera fase de reanimación

Quiste tirogloso: experiencia de cinco años en el Hospital ABC / Thyroglosal duct cyst: ABC Hospital's five years experience

El quiste tirogloso es el resultado de la falla en la obliteración del conducto tirogloso. Es la lesión quística cervical más frecuente. Durante el periodo 1988 a 1992, la experiencia del Hospital ABC incluyó 18 casos operados: 12 mujeres (66 por ciento) y seis hombres (34 por ciento). Predominó el grupo de cinco a diez años de edad (55 por ciento). El tiempo de evolución más frecuente fue menor a un mes (27 por ciento). El diagnóstico se basó en los hallazgos clínicos. La técnica quirúrgica más empleada fue la resección simple del quiste con tres casos de recidiva