Papel de las hormonas progesterona, estradiol y oxitocina en la función del miometrio durante el embarazo y el trabajo de parto / Role of progesterone, estradiol and oxytocin hormones in myometrial function during pregnancy and labor

Resumen El trabajo de parto es la transición de un estado de inactividad y relajación muscular a un estado de excitación, en el cual la capa muscular del útero (miometrio) realiza crecientes contracciones coordinadas para llevar a cabo la expulsión del feto y la placenta. Durante el inicio del trabajo de parto, el miometrio experimenta una serie de cambios fisiológicos, bioquímicos y moleculares, pasando de un estado de quiescencia a un fenotipo contráctil que inducirá el parto. En parte, esto es provocado por la acción de las hormonas progesterona, estradiol y oxitocina. En general, la progesterona mantiene la quiescencia del miometrio durante el embarazo al inhibir la expresión de moléculas proinflamatorias y proteínas asociadas a la contracción, mientras que al término del embarazo, el estradiol induce la expresión de dichas moléculas. Por su parte, la oxitocina induce un aumento en la concentración de calcio intracelular para llevar a cabo las contracciones de los miocitos uterinos. El objetivo del presente trabajo es presentar un resumen acerca de los mecanismos moleculares involucrados en la regulación de la actividad de las células miometriales por medio de las hormonas progesterona, estradiol y oxitocina, así como discutir las perspectivas de esta interesante área de investigación.

Abstract Labor is the transition from a state of inactivity and muscle relaxation to a state of muscle excitation, in which the muscular layer of the uterus (myometrium) performs increasingly coordinated contractions to deliver the fetus and expel the placenta. During the onset of labor, the myometrium undergoes a series of physiological, biochemical, and molecular changes, allowing the tissue to transition from a quiescent state to a contractile phenotype that will support labor. This is partly caused by the action of the hormones progesterone, estradiol, and oxytocin. In general, progesterone maintains the quiescence of the myometrium during pregnancy by decreasing the expression of proinflammatory molecules and contraction-associated proteins. In contrast, at the end of pregnancy, estradiol induces the expression of these molecules. For its part, oxytocin induces an increase in intracellular calcium concentration to carry out the contractions of uterine myocytes. The objective of this review is to present a summary of the molecular mechanisms involved in regulating myometrial cell activity through the hormones progesterone, estradiol and oxytocin, as well as to discuss the perspectives of this exciting area of research.

Tumor de músculo liso uterino de potencial maligno incierto (STUMP): reporte de caso y revisión de la literatura / Uterine smooth muscle tumor of uncertain malignant potential (STUMP): case report and literature review

Myometrial smooth muscle neoplasms are the most common gynecologic tumors with a prevalence of 70-80% at age 50. Among women undergoing hysterectomy or myomectomy for a suspected diagnosis of leiomyoma, 0.01% receive a diagnosis of STUMP. Clinically, the average age of presentation is between 41-48 years. Tumors ranging from 3 to 30 cm have been described. Signs and symptoms are similar to leiomyomas, such as abnormal uterine bleeding, anemia, dysmenorrhea, pelvic pain, pelvic mass, infertility or other types of pain secondary to compression of adjacent organs. Due to the limited literature available, there is no definite management consensus, and treatment and follow-up options are limited to observational studies. The standard treatment is total hysterectomy with or without bilateral salpingo-oophorectomy; if fertility has already been completed, there is no role for adjuvant hormonal therapy or chemotherapy. The overall 5-year survival is 92-100%. A case of a 31-year-old woman with STUMP is presented.

Embarazo ectópico intramural: reporte de caso / ntramural ectopic pregnancy: case report

El embarazo ectópico intramural es la gestación a nivel de miometrio sin tener conexión con las trom-pas de Falopio o cavidad endometrial, es extremadamente raro; representa menos del 1% de todos los embarazos ectópicos. Este tipo de embarazo es difícil de diagnosticar, las modalidades diagnósticas incluyen ultrasonido, tomografía computarizada y re-sonancia magnética. Se han descrito factores de riesgo para esta rara gestación ectópica que incluyen trauma uterino previo, ade-nomiosis, cirugía pélvica y fertilización in vitro. Descripción de caso clínico: Primigesta de 32 años que se presentó a consulta con amenorrea y prueba de embarazo positiva, se realiza ultra-sonido donde se observa endometrio lineal sin evidencia de saco gestacional. Se deja como impresión diagnóstica embarazo tem-prano y se cita en 2 semanas, al presentarse se envía a realizar gonadotropina coriónica humana fracción beta que reportó 600 UI/ml. 2 días después se repite la prueba y reporta 5000 UI/ml. La paciente inicia con dolor pélvico de moderada intensidad tipo cólico, acompañado de sangrado transvaginal. Se realiza un ter-cer ultrasonido pélvico que reporta imagen de 1.63 por 1.50 cms heterogénea, irregular compatible con un saco gestacional conte-niendo embrión sin latido cardiaco en su interior correspondiente a un embarazo intramural y presencia de mioma subseroso. Se decide realizar laparotomía exploratoria en donde se extrae saco gestacional y mioma, sin complicaciones. Conclusiones: Los es-tudios de imagen y laboratorio son necesarios para el diagnóstico del embarazo intramural, dado que es altamente inusual no hay un consenso sobre su manejo, en este caso el manejo fue qui-rúrgico...(AU)

Mioma intraligamentario de gran tamaño en una adolescente / Intra-ligamentary leiomyoma of giant elements in adolescent patient

Resumen ANTECEDENTES: Los leiomiomas uterinos son los tumores benignos ginecológicos más frecuentes en las mujeres en edad reproductiva; por tanto, son extremadamente raros en las adolescentes (menos de 1%) y solo se encuentran reportes de caso en la bibliografía. CASO CLÍNICO: Paciente de 16 años, con tumor suprapúbico de rápido crecimiento, acompañado de dolor abdominal generalizado, enviada a la unidad médica con diagnóstico de miomatosis uterina para descartar su malignidad. El ultrasonido pélvico reportó múltiples lesiones hipoecoicas diseminadas en el miometrio, similares a metástasis. La tomografía abdomino-pélvica informó hepatomegalia, a expensas del lóbulo izquierdo y leiomiomas intramurales de medianos y grandes elementos; los marcadores tumorales se encontraron en límites normales. En la laparotomía se encontró una tumoración interligamentaria izquierda de 25 cm; el estudio histopatológico reportó: leiomioma uterino de patrón histológico convencional. CONCLUSIONES: El cuadro clínico de los leiomiomas en adolescentes representa un reto clínico por la edad, signos, síntomas y necesidad de preservación de la función reproductiva, aspectos decisivos a la hora de decidir el tratamiento.

Abstract BACKGROUND: The uterine leiomyomas are the most common gynecological benign tumors in fertile females; however, they are very rare in adolescents (less than 1%) and there are only a few reports in the literature. CLINICAL CASE: A 16-year-old patient with a fast-growing suprapubic tumor, accompanied by generalized abdominal pain, sent to the hospital with diagnosis of pelvic tumor probable uterine miomatosis, to rule out malignant tumor. Pelvic ultrasound was performed with a report of multiple disseminated hypoechoic lesions in myometrium giving appearance of metastasis, without being the characteristic images of myomas, pelvic abdominal tomography reported hepatomegaly of the left lobe, intramural leiomyomas of medium and large elements, tumor markers within normal limits. The laparotomy was performed, left intraligamentary myoma of giant elements was located; and the histopathological study reported uterine leiomyoma of conventional histological pattern. CONCLUSIONS: The clinical of leiomyomas in adolescent patients represents a challenge for the gynecologist. The age, symptomatology, and preservation of reproductive function are important aspects to decide the therapeutic regimen.

Evaluation of KI-67 expression in uterine leiomyoma and in healthy myometrium: a pilot study

SUMMARY OBJECTIVE Evaluate the expression of KI-67 in uterine leiomyomas and adjacent myometrial tissue and verify the existence of a correlation between clinical parameters and KI-67 expression in tumors. METHODS This is a cross-sectional, controlled, analytical study. Samples of leiomyomas and myometrium were obtained from patients who underwent hysterectomy. The samples were processed by immunohistochemistry using KI-67 antibody, and the expression was evaluated by two blinded observers. Student›s T-test was used for comparison of means, and Pearson›s P test for correlation with clinical parameters. RESULTS A total of 9 patients were included in the study. The mean age was 40.7 years, ranging from 35 to 44 years. The mean expression of KI-67 in myometrium was 1.63%, and, in leiomyomas, 5.96% (p <0.001). The highest expression of KI-67 was moderately related to the severity of anemia, bleeding, and pain level. CONCLUSION The expression of KI-67 in normal myometrium was significantly lower than in leiomyomas. The highest expression of KI-67 was moderately related to the severity of anemia, bleeding, and pain level in the patients of this study.

RESUMO OBJETIVO Avaliar a expressão do KI-67 em leiomiomas uterinos e tecido miometrial adjacente e verificar a existência de correlação entre parâmetros clínicos e expressão do KI-67 em tumores. MÉTODOS Estudo transversal, controlado e analítico. Amostras de leiomiomas e miométrio foram obtidas de pacientes que realizaram histerectomia. As amostras foram processadas por imuno-histoquímica utilizando anticorpo para KI-67 e a expressão avaliada por dois observadores cegos. O teste t de Student foi utilizado para comparação de médias e o teste P de Pearson para correlação com parâmetros clínicos. RESULTADOS Um total de 9 pacientes foi incluído no estudo. A idade média foi de 40,7 anos, variando de 35 a 44 anos. A expressão média do KI-67 no miométrio foi de 1,63% e nos leiomiomas de 5,96% (p <0,001). A maior expressão do KI-67 foi moderadamente relacionada com a gravidade da anemia, sangramento e nível de dor. CONCLUSÃO A expressão do KI-67 no miométrio normal foi significativamente menor que nos leiomiomas. A maior expressão do KI-67 foi moderadamente relacionada à gravidade da anemia, sangramento e nível de dor nos pacientes deste estudo.

Útero de Couvelaire, consecuencia del desprendimiento prematuro de placenta normoinserta. Reporte de un caso / Couvelaire uterus, consequence of premature placental detachment. A case report

Resumen ANTECEDENTES El útero de Couvelaire, o apoplejía uteroplacentaria, es una infiltración hemática del miometrio uterino debida a la formación de un hematoma retroplacentario masivo. El útero de Couvelaire es una de las complicaciones más severas del desprendimiento prematuro de placenta; aparece en 0.4 a 1% de los embarazos. CASO CLÍNICO Paciente de 26 años de edad, primigesta, con 37 semanas de gestación y seis días establecidos por la fecha de la última menstruación, procedente de La Esperanza, Intibucá, Honduras. La paciente llegó al hospital con amaurosis, cifras tensionales elevadas, preeclampsia atípica y óbito extrahospitalario, con grado de maceración I. La paciente tuvo convulsiones, sin mayores datos. Al examen físico tuvo: presión arterial de 130-100 mmHg, Glasgow 10-15, frecuencia cardiaca fetal 0 lpm, altura de fondo uterino de 34 cm, dilatación del cuello uterino de 10 cm, altura de presentación +1 y presentación cefálica. Exámenes de laboratorio: proteinuria cualitativa +++, leucocitosis con predominio neutrofílico y creatinina aumentada. Los tiempos de coagulación se reportaron anormales. La paciente se recibió inestable en el servicio de Urgencias, por útero hipotónico. En la laparotomía exploradora se encontró al útero aumentado de tamaño, flácido, con infiltración de 90%, con predominio del lado izquierdo, diagnóstico compatible con útero de Couvelaire. CONCLUSIÓN Los hallazgos de útero de Couvelaire son excepcionales y deben tenerse en cuenta porque pueden resultar en mortalidad materna o fetal.

Abstract BACKGROUND Couvelaire uterus or uteroplacental apoplexy is a blood infiltration of the uterine myometrium due to the formation of a massive retroplacental hematoma. Couvelaire uterus is one of the most severe complications in placental detachment occurring in 0.4 to 1% of pregnancies. CLINIC CASE 26-year-old female patient, primigravida, with 37 weeks and six days given by her last menstruation day, from La Esperanza, Intibucá, Honduras. The patient presented amaurosis, high tension figures and extrahospitalary fetal death with maceration grade 1. Her mother refers the patient had seizures but she doesn't know the data. In the physical examination the patient had a blood pressure of 130/100 mmhg, glasglow 11/15, fetal heart rate of 0 bpm, uterine fundus height of 34 cm, cervix dilation of 10 cm, presentation height +1, and cephalic presentation. Laboratory tests included qualitative proteinuria +++, leukocytosis with neutrophilic predominance and increased creatinine levels. Coagulation times were reported abnormal. The patient was unstable so she was received in cubicle of severes by a hypotonic uterus. An exploratory laparotomy was performed by which the results were an enlarged flaccid uterus with 90% of infiltration with predominance in the left side, a diagnosis compatible with Couvelaire Uterus. CONCLUSION The findings of Couvelaire Uterus are infrequent, so we must take into account this pathology because it can lead to maternal and fetal mortality.

Histologia e morfometria em cornos uterinos de cadelas nulíparas, multíparas e tratadas com contraceptivos / Histology and morphometry in uterus horns of nulliparous bitches, multiparous ones and bitches treated with contraceptives

Dados histológicos e morfométricos foram obtidos de útero de cadelas nulíparas (n=6), multíparas (n=6) e de cadelas tratadas com contraceptivo (n=6). Para esse fim foram usadas seis amostras de cornos uterinos, em corte médio, para cada grupo. As mensurações das espessuras da parede uterina, endométrio total, miométrio total, miométrio interno, miométrio externo, estrato vascular e diâmetro das glândulas endometriais normais não foram estatisticamente significantes entre as cadelas multíparas e tratadas, com exceção para a altura do epitélio de glândulas normais. As mensurações das espessuras da parede uterina, endométrio total, miométrio total, miométrio interno, diâmetro das glândulas normais e altura do epitélio glandular foram significantes, comparando cadelas nulíparas com as multíparas e/ou tratadas, com exceção para as espessuras do miométrio externo e estrato vascular. Diante dos resultados obtidos, pode-se concluir que os dados numéricos confirmam que (1) o uso de anticoncepcionais e sucessivas gestações afetam a estrutura uterina em seu total; (2) o miométrio externo e estrato vascular foram as regiões que menos sofreram alterações comparando-se os 3 grupos; (3) as variações morfológicas ocorreram com a mesma intensidade no endométrio e miométrio totais para as cadelas tratadas e multíparas, e (4) a presença de glândulas endometriais dilatadas foi o diferencial encontrado nas cadelas tratadas, pois as mesmas estavam ausentes nas multíparas e nulíparas.

Histological and morphometric data were obtained from uterus of nulliparous bitches (n=6), multiparous ones (n=6), and bitches treated with contraceptive (n=6). Six samples of uterine horns, cut in average for each group. Measurements of the thickness of the uterine wall, total endometrium, total myometrium, internal myometrium, external myometrium, vascular layer and diameter of normal endometrial glands were not statistically significant between the treated and multiparous bitches, except for the height of the epithelium of normal glands. Measurements of thickness of the uterine wall, total endometrium, total myometrium, myometrium internal diameter and height of the glands of normal glandular epithelium were significant, comparing nulliparous with multiparous bitches and/or treated, except for thickness of the myometrium and vascular outer layer. It can be concluded that (1) the use of contraceptives and successive pregnancies affected uterine structures in its full, (2) the vascular layer and external myometrium were the regions with less variation, (3) morphological changes occurred with the same intensity in the total endometrium and myometrium of treated and multiparous bitches; and (4) the presence of dilated endometrial glands was the difference found in the treated bitches, because they were absent in nulliparous and multiparous ones.

Gravidez ectópica na cicatriz uterina de cesárea: relato de caso / Cesarean scar ectopic pregnancy: a case report

Gravidez ectópica na cicatriz de cesárea é a forma mais rara de gravidez ectópica e provavelmente uma das mais perigosas em função dos riscos de ruptura e hemorragia volumosa. Essa situação deve ser diferenciada da gravidez cervical e de abortamento em curso, para que o tratamento apropriado seja imediatamente oferecido. Desde o advento da ultra-sonografia transvaginal, a gravidez ectópica na cicatriz de cesárea pode ser diagnosticada precocemente na gestação e, para isso o ultra-sonografista deve estar familiarizado com e atento aos critérios diagnósticos, especialmente em mulheres com cicatriz de cesárea prévia. Descrevemos aqui um caso de gravidez ectópica em cicatriz de cesárea, cujo diagnóstico foi tardio, havendo apresentação de involução espontânea.

Ectopic pregnancy in a cesarean scar is the rarest form of ectopic pregnancy and probably the most dangerous one because of the risk of uterine rupture and massive hemorrhage. This condition must be distinguished from cervical pregnancy and spontaneous abortion in progress, so that the appropriate treatment can be immediately offered. Since the advent of endovaginal ultrasonography, ectopic pregnancy in a cesarean scar can be diagnosed early in pregnancy if the sonographer is familiarized with the diagnostic criteria of this situation, especially in women with previous cesarean scar. Here we describe a case of ectopic pregnancy in a cesarean scar in which the diagnosis was considerably late, with presentation of spontaneous regression.