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1.
J Clin Endocrinol Metab ; 106(5): 1530-1539, 2021 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-33367768

RESUMEN

Virilization is the medical term for describing a female who develops characteristics associated with male hormones (androgens) at any age, or when a newborn girl shows signs of prenatal male hormone exposure at birth. In girls, androgen levels are low during pregnancy and childhood. A first physiologic rise of adrenal androgens is observed at the age of 6 to 8 years and reflects functional activation of the zona reticularis of the adrenal cortex at adrenarche, manifesting clinically with first pubic and axillary hairs. Early adrenarche is known as "premature adrenarche." It is mostly idiopathic and of uncertain pathologic relevance but requires the exclusion of other causes of androgen excess (eg, nonclassic congenital adrenal hyperplasia) that might exacerbate clinically into virilization. The second modest physiologic increase of circulating androgens occurs then during pubertal development, which reflects the activation of ovarian steroidogenesis contributing to the peripheral androgen pool. However, at puberty initiation (and beyond), ovarian steroidogenesis is normally devoted to estrogen production for the development of secondary female bodily characteristics (eg, breast development). Serum total testosterone in a young adult woman is therefore about 10- to 20-fold lower than in a young man, whereas midcycle estradiol is about 10- to 20-fold higher. But if androgen production starts too early, progresses rapidly, and in marked excess (usually more than 3 to 5 times above normal), females will manifest with signs of virilization such as masculine habitus, deepening of the voice, severe acne, excessive facial and (male typical) body hair, clitoromegaly, and increased muscle development. Several medical conditions may cause virilization in girls and women, including androgen-producing tumors of the ovaries or adrenal cortex, (non)classical congenital adrenal hyperplasia and, more rarely, other disorders (also referred to as differences) of sex development (DSD). The purpose of this article is to describe the clinical approach to the girl with virilization at puberty, focusing on diagnostic challenges. The review is written from the perspective of the case of an 11.5-year-old girl who was referred to our clinic for progressive, rapid onset clitoromegaly, and was then diagnosed with a complex genetic form of DSD that led to abnormal testosterone production from a dysgenetic gonad at onset of puberty. Her genetic workup revealed a unique translocation of an abnormal duplicated Y-chromosome to a deleted chromosome 9, including the Doublesex and Mab-3 Related Transcription factor 1 (DMRT1) gene. LEARNING OBJECTIVES: Identify the precise pathophysiologic mechanisms leading to virilization in girls at puberty considering that virilization at puberty may be the first manifestation of an endocrine active tumor or a disorder/difference of sex development (DSD) that remained undiagnosed before and may be life-threatening. Of the DSDs, nonclassical congenital adrenal hyperplasia occurs most often.Provide a step-by-step diagnostic workup plan including repeated and expanded biochemical and genetic tests to solve complex cases.Manage clinical care of a girl virilizing at puberty using an interdisciplinary team approach.Care for complex cases of DSD manifesting at puberty, such as the presented girl with a Turner syndrome-like phenotype and virilization resulting from a complex genetic variation.


Asunto(s)
Hiperplasia Suprarrenal Congénita/terapia , Pubertad/fisiología , Virilismo/terapia , Hiperplasia Suprarrenal Congénita/sangre , Hiperplasia Suprarrenal Congénita/complicaciones , Hiperplasia Suprarrenal Congénita/genética , Adrenarquia/fisiología , Andrógenos/sangre , Niño , Femenino , Humanos , Pubertad/genética , Virilismo/sangre , Virilismo/diagnóstico , Virilismo/genética
2.
Life (Basel) ; 10(9)2020 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-32867158

RESUMEN

BACKGROUND: After application of iodinated contrast media (CM), a pronounced deterioration of the microcirculation in skin and myocardium was reported. Clinically, the repeated application of CM, especially, led to an increase of the renal resistance index (RRI). With respect to the transiency of the RRI increase, it is reasonable to assume that the deterioration of blood flow could be due to transient blood stasis caused by reversible morphologic cell alterations due to osmotic discrepancies between CM and human blood. Therefore, the hypothesis was investigated whether CM are able to induce in vivo such blood stasis and cell deformations in the renal vasculature of well-hydrated pigs. METHODS: The in vivo study was performed as a prospective randomized examination to compare the effects of two different CM in 16 pigs (German Landrace). Pigs were randomized to receive either Iodixanol (n = 8), or Iopromide (n = 8). Each animal received 10 injections separated by 5-min intervals via the suprarenal aorta at a rate of 10 mL/s according to the usual procedure during a cardiac catheter examination. Finally, the kidneys were explanted and processed for histology (H & E staining and fibrin staining according to Weigert) as well as for scanning electron microscopy (SEM) with regards to morphologic correlates explaining the changes in the microcirculation. RESULTS: In each of the predefined four categories of vascular diameters, blood stasis were found, but clearly more often after application of Iopromide than after application of Iodixanol (p < 0.001). In addition, Iopromide induced more blood stasis in all of the examined kidney regions compared to Iodixanol (p = 0.0001). There were no obstructive events in the middle cortex following the application of Iodixanol. Except for the region around a puncture channel of a placed-in catheter probe, no fibrin was detected in Weigert's fibrin-stained samples, neither around the histologically assessed thrombi nor in vessels with blood stasis. Complementary SEM analyses revealed in a few cases only a slight generation of fibrin and thrombi and deformations, such as echinocyte and "box-like" deformations. CONCLUSIONS: According to previous in vitro studies, pathological erythrocyte deformations, such as echinocyte and box-like formation of erythrocytes, were observed also in vivo. In addition, blood stasis and/or thrombi could be detected in histological samples from explanted kidneys from young pigs after repeated in vivo administration of CM. In only a few cases, mural platelet aggregates within minimal fibrin meshes occurred only after the application of Iopromide.

3.
J Clin Endocrinol Metab ; 105(3)2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31665438

RESUMEN

CONTEXT: Standardized description of external genitalia is needed in the assessment of children with atypical genitalia. OBJECTIVES: To validate the External Genitalia Score (EGS), to present reference values for preterm and term babies up to 24 months and correlate obtained scores with anogenital distances (AGDs). DESIGN, SETTING: A European multicenter (n = 8) validation study was conducted from July 2016 to July 2018. PATIENTS AND METHODS: EGS is based on the external masculinization score but uses a gradual scale from female to male (range, 0-12) and terminology appropriate for both sexes. The reliability of EGS and AGDs was determined by the interclass correlation coefficient (ICC). Cross-sectional data were obtained in 686 term babies (0-24 months) and 181 preterm babies, and 111 babies with atypical genitalia. RESULTS: The ICC of EGS in typical and atypical genitalia is excellent and good, respectively. Median EGS (10th to 90th centile) in males < 28 weeks gestation is 10 (8.6-11.5); in males 28-32 weeks 11.5 (9.2-12); in males 33-36 weeks 11.5 (10.5-12) and in full-term males 12 (10.5-12). In all female babies, EGS is 0 (0-0). The mean (SD) lower/upper AGD ratio (AGDl/u) is 0.45 (0.1), with significant difference between AGDl/u in males 0.49 (0.1) and females 0.39 (0.1) and intermediate values in differences of sex development (DSDs) 0.43 (0.1). The AGDl/u correlates with EGS in males with typical genitalia and in atypical genitalia. CONCLUSIONS: EGS is a reliable and valid tool to describe external genitalia in premature and term babies up to 24 months. EGS correlates with AGDl/u in males. It facilitates standardized assessment, clinical decision-making and multicenter research.


Asunto(s)
Trastornos del Desarrollo Sexual/diagnóstico , Genitales Femeninos/anatomía & histología , Genitales Masculinos/anatomía & histología , Edad Gestacional , Estudios Transversales , Europa (Continente) , Femenino , Genitales Femeninos/crecimiento & desarrollo , Genitales Masculinos/crecimiento & desarrollo , Humanos , Recién Nacido , Recien Nacido Prematuro , Masculino , Valores de Referencia , Reproducibilidad de los Resultados
4.
Sci Rep ; 7(1): 13125, 2017 10 13.
Artículo en Inglés | MEDLINE | ID: mdl-29030579

RESUMEN

The administration of iodinated contrast media (CM) can cause microcirculatory disorder leading to acute renal dysfunction. In a prospective, randomized investigation two CM (Iodixanol vs Iopromide) were compared in 16 pigs. Each animal received 10 intra-aortal injections (5 ml Iodixanol or 4.32 ml Iopromide). Microcirculation was assessed using contrast-enhanced ultrasound (CEUS) directly on the kidney surface using time-to-peak (TTP) and blood-volume-analysis. Macroscopic observations were documented. Post mortem residual CM distribution in the kidneys was detected using X-ray. TTP was significantly prolonged over the descending vasa recta of the Iopromide group. This coincided with a visible marble-like pattern on the kidney surface occurring in 30 out of 80 Iopromide-injections but in 4 out of 80 Iodixanol-injections (p = 0.007). The blood volume over the entire kidney did not change after Iodixanol-application, but decreased by about 6.1% after Iopromide-application. The regional blood volume in the renal cortex showed a tendency to decrease by about 13.5% (p = 0.094) after Iodixanol-application, and clearly decreased by about 31.7% (p = 0.022) after Iopromide-application. The study revealed a consistent influence of repeated injections of two different CM on the kidney perfusion using three different imaging methods (CEUS analysis, macroscopic observation and X-ray analysis).


Asunto(s)
Medios de Contraste/análisis , Riñón/diagnóstico por imagen , Animales , Medios de Contraste/efectos adversos , Hemodinámica/efectos de los fármacos , Yohexol/efectos adversos , Yohexol/análogos & derivados , Yohexol/análisis , Microcirculación/efectos de los fármacos , Microcirculación/fisiología , Porcinos , Ácidos Triyodobenzoicos/efectos adversos , Ácidos Triyodobenzoicos/análisis
5.
Hepatology ; 56(3): 873-83, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22487943

RESUMEN

UNLABELLED: The strength of antiviral T cell responses correlates with clearance of hepatitis B virus (HBV) infection, but the immunological mechanisms mitigating or suppressing HBV-specific T cells are still poorly understood. In this study, we examined the role of CD4(+) Foxp3(+) regulatory T cells (Tregs) in a mouse model of acute HBV infection. We initiated HBV infection via an adenoviral vector transferring a 1.3-fold overlength HBV genome (AdHBV) into transgenic DEREG mice, where Tregs can be transiently but selectively depleted by injection of diphtheria toxin. The effect of Treg depletion on the outcome of HBV infection was characterized by detailed virological, immunological, and histopathological analysis. Numbers of Tregs increase in the liver rapidly after initiation of HBV replication. Initial depletion of Tregs revealed their complex regulatory function during acute infection. Tregs mitigated immunomediated liver damage by down-regulating the antiviral activity of effector T cells by limiting cytokine production and cytotoxicity, but did not influence development of HBV-specific CD8 T cells or development of memory T cells. Furthermore, Tregs controlled the recruitment of innate immune cells such as macrophages and dendritic cells to the infected liver. As a consequence, Tregs significantly delayed clearance of HBV from blood and infected hepatocytes. CONCLUSION: Tregs limit immunomediated liver damage early after an acute infection of the liver, thereby contributing to conservation of tissue integrity and organ function at the cost of prolonging virus clearance.


Asunto(s)
Factores de Transcripción Forkhead/inmunología , Hepatitis B/inmunología , Hepatitis B/virología , Hígado/inmunología , Linfocitos T Reguladores/inmunología , Enfermedad Aguda , Animales , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos
7.
Surgery ; 140(6): 907-13; discussion 913, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-17188137

RESUMEN

BACKGROUND: Localization of hyperfunctioning parathyroid glands in patients with previous cervical operations is not always successful with noninvasive methods such as ultrasound, sestamibi scan, or magnetic resonance imaging. The aim of our study was to evaluate the results of selective venous sampling (SVS) of intact parathyroid hormone (PTH) in patients undergoing surgery for primary (75%) or secondary (25%) hyperparathyroidism (HPT). METHODS: Between January 2000 and January 2006, SVS for PTH was performed in 51 consecutive patients with persistent or recurrent HPT or patients with previous cervical explorations. The results of SVS were compared with those of noninvasive localization studies. RESULTS: Successful surgical treatment was achieved in 47 of 51 patients (92%). SVS had a sensitivity of 83.3% for the correct localization of a parathyroid adenoma (79.5%) or hyperplastic parathyroid glands (91.6%). False-positive or indeterminate results of SVS were found in 6% and 2%, respectively, of the patients. Ultrasound detected enlarged parathyroid glands with a sensitivity of 33.3%, and sestamibi scan with a sensitivity of 57.1%. CONCLUSIONS: Compared with noninvasive localization studies, SVS for PTH yielded the best results for recurrent or persistent HPT and for patients with previous neck explorations. SVS is strongly recommended in reoperative surgery for HPT with indeterminate results of noninvasive methods.


Asunto(s)
Hiperparatiroidismo Primario/sangre , Hiperparatiroidismo Primario/cirugía , Hiperparatiroidismo Secundario/sangre , Hiperparatiroidismo Secundario/cirugía , Glándulas Paratiroides/patología , Hormona Paratiroidea/sangre , Adulto , Anciano , Cateterismo/métodos , Diagnóstico por Imagen/métodos , Femenino , Humanos , Hiperparatiroidismo Primario/diagnóstico , Hiperparatiroidismo Secundario/diagnóstico , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Glándulas Paratiroides/diagnóstico por imagen , Glándulas Paratiroides/metabolismo , Estudios Prospectivos , Cintigrafía/métodos , Reoperación , Sensibilidad y Especificidad , Tecnecio Tc 99m Sestamibi , Ultrasonografía
8.
Gastroenterology ; 129(5): 1430-6, 2005 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16285944

RESUMEN

BACKGROUND & AIMS: Studies in animals and humans suggest a role for peptide YY (PYY3-36) in regulating satiety. The physiologic role of PYY3-36, however, has not been investigated in detail. METHODS: The present study was designed to examine PYY release in response to 2 meals differing in their calorie content and to relate the plasma levels to those obtained after exogenous infusion. In a second step, the effect of graded intravenous doses (0, 0.2, 0.4, and 0.8 pmol.kg(-1).min(-1)) of synthetic human PYY3-36 on food intake was investigated in healthy male volunteers in a double-blind, placebo-controlled fashion. RESULTS: Plasma PYY concentrations increased in response to food intake reflecting the size of the calorie load. Graded PYY3-36 infusions resulted in a dose-dependent reduction in food intake (maximal inhibition, 35%; P < .001 vs control) and a similar reduction in calorie intake (32%; P < .001). Fluid ingestion was also reduced by PYY (18% reduction; P < .01). Nausea and fullness were the most common side effects produced by PYY, especially at the highest dose. Furthermore, subjects experienced less hunger and early fullness in the premeal period during PYY3-36 infusion at the highest dose (P < .05). CONCLUSIONS: This study shows that intravenous infusions of PYY3-36 decrease spontaneous food intake; the inhibition is, however, only significant at pharmacologic plasma concentrations. Whether PYY3-36 has a physiologic role in the regulation of satiety in humans remains to be defined.


Asunto(s)
Apetito/efectos de los fármacos , Ingestión de Alimentos/efectos de los fármacos , Péptido YY/administración & dosificación , Adulto , Método Doble Ciego , Conducta Alimentaria/efectos de los fármacos , Femenino , Humanos , Infusiones Intravenosas , Masculino , Fragmentos de Péptidos , Péptido YY/efectos adversos , Péptido YY/sangre , Placebos , Respuesta de Saciedad/efectos de los fármacos
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