Paraganglioma cuerpo carotídeo: experiencia en 20 años y revisión de la literatura / Carotid body paraganglioma: 20-year experience and literature review

Resumen El paraganglioma carotideo es un tumor infrecuente, originado de las células de la cresta neural. Raramente son secretores y tienen un bajo potencial maligno. El diagnóstico es difícil y requiere una alta sospecha clínica, combinada con estudios imagenológicos. Su tratamiento está basado en la cirugía, con especial cuidado de las estructuras vasculonerviosas que se encuentran en intimo contacto. Se describe la casuística de paragangliomas de cuerpo carotídeo en Clínica Las Condes y compararla con una revisión de la literatura actualizada del tema.

Abstract Carotid paraganglioma is a rare tumor, originated from neural crest cells. Usually they lack hormone secretion function, and have a low malignant potential. Diagnosis is difficult, and requires high clinical suspicious, combined with image and pathologic findings. Its treatment is based on surgery, with special care of close anatomic relation with important vascular-nervous structures. Here, we present cases of carotid paragangliomas evaluated at Clinica Las Condes comparing them with an updated literature review.

Prevalence and molecular characterisation of carbapenemase-producing Enterobacterales in an outbreak-free setting in a single hospital in Uruguay.

OBJECTIVES: This study aimed to characterise all carbapenemase-producing enterobacteria (CPE) isolates obtained from an outbreak-free setting in Uruguay. METHODS: We studied 12 CPE isolated from Hospital de Clínicas between 2012-2016. Bacterial identification and antibiotic susceptibility testing were performed using VITEK®2 and Sensititre or agar dilution, respectively. Antimicrobial resistance genes and mobile genetic elements were identified by PCR and sequencing. Multilocus sequence typing was performed for Klebsiella pneumoniae. Plasmid conjugation was assessed, plasmid size was estimated by S1-PFGE and plasmid incompatibility groups were sought by PCR. RESULTS: Among 8364 enterobacteria, 12 CPE were isolated from urine, blood culture, wound, peritoneal fluid and punch samples. NDM-1 was the most prevalent carbapenemase, followed by VIM-2 and KPC-2. All isolates were resistant to gentamicin, cefotaxime, ceftazidime, trimethoprim/sulfamethoxazole, ciprofloxacin and imipenem and were susceptible to fosfomycin. We characterised six class 1 integrons: dfrA12-orfF-aadA2; aacA4-blaOXA-2-orfD; aadB-aadA2; dfrA1; aadB-blaOXA-10-aadA1; and blaVIM-2-dfrA7. An association between various aminoglycoside, ß-lactam and fluoroquinolone resistance genes were observed, some of them located in transferable plasmids belonging to incompatibility groups IncC, IncHI1 and IncM1. We described a new composite transposon (assigned Tn6935) including blaNDM-1 flanked by two directly-oriented copies of a Tn3-like element ISKox2-like family transposase. The sequence types of K. pneumoniae isolates were ST11, ST14 and ST661. CONCLUSIONS: The presence of CPE is sporadic and could be due to measures taken by the Public Health Committee. Nevertheless, the coexistence of several resistance mechanisms and their presence in conjugative plasmids and high-risk clones is worrisome.

Diagnóstico y tratamiento del síndrome de piel sensible: un algoritmo para la práctica clínica habitual / Diagnosis and Treatment of Sensitive Skin Syndrome: An Algorithm for Clinical Practice

Tradicionalmente, la piel sensible se ha considerado como un problema cosmético o como una alteración puramente psicosomática con un fuerte componente subjetivo. Sin embargo, diversos estudios científicos sobre sus procesos fisiopatológicos y su etiopatogenia han demostrado que se trata de una entidad compleja que ya diversos autores consideran un síndrome neurodermatológico. Sus características hacen que su diagnóstico y tratamiento puedan resultar complicados en la práctica clínica habitual, siendo necesarias herramientas sencillas que se puedan usar de rutina, tanto para identificar esta entidad, que puede presentarse acompañada de otra patología, como para su manejo independiente. En este trabajo realizamos una revisión práctica de los avances científicos más recientes el campo de la piel sensible que justifican su consideración individual y ofrecen herramientas para identificarla y tratarla. Proponemos algoritmos de diagnóstico y de tratamiento basados en las evidencias de la literatura y en la opinión de los expertos que firman este artículo

Sensitive skin has traditionally been viewed as a cosmetic problem or as a purely psychosomatic alteration with a major subjective component. Different studies of its pathophysiologic etiology, however, have shown it to be a complex entity that several authors now consider to be a neurodermatological syndrome. Because of this complexity, skin sensitivity can be difficult to diagnose and treat, particularly considering that it may present with another disease. Simple tools applicable to clinical practice are thus necessary to identify and manage this disease as an independent entity. In this study, we perform a practical review of the most recent scientific advances in the area of sensitive skin that justify it being considered an individual entity, and provide tools for its identification and treatment. We propose diagnostic and treatment algorithms based on evidence from the literature and our experience and expertise

Diagnosis and Treatment of Sensitive Skin Syndrome: An Algorithm for Clinical Practice. / Diagnóstico y tratamiento del síndrome de piel sensible: un algoritmo para la práctica clínica habitual.

Sensitive skin has traditionally been viewed as a cosmetic problem or as a purely psychosomatic alteration with a major subjective component. Different studies of its pathophysiologic etiology, however, have shown it to be a complex entity that several authors now consider to be a neurodermatological syndrome. Because of this complexity, skin sensitivity can be difficult to diagnose and treat, particularly considering that it may present with another disease. Simple tools applicable to clinical practice are thus necessary to identify and manage this disease as an independent entity. In this study, we perform a practical review of the most recent scientific advances in the area of sensitive skin that justify it being considered an individual entity, and provide tools for its identification and treatment. We propose diagnostic and treatment algorithms based on evidence from the literature and our experience and expertise.

Carcinoma adenoide quístico de cavidad nasal y senos paranasales: experiencia de 5 años en Clínica Las Condes de Santiago de Chile / Adenoid cystic carcinoma of nasal cavity and paranasal sinuses: 5 years experience in las Condes Clinic of Santiago of Chile

RESUMEN Introducción: El carcinoma adenoide quístico es una neoplasia originada en glándulas exocrinas de todo el cuerpo, principalmente en glándulas salivales mayores. En cavidad nasal y senos paranasales es poco frecuente y se caracteriza por presentar una alta frecuencia de recurrencia y de metástasis a distancia posterior a su remisión y a pesar de su tratamiento. Objetivo: Describir características de una serie de casos de pacientes con carcinoma adenoide quístico de cavidad nasal y senos paranasales operados. Material y método: Estudio descriptivo-retrospectivo. Período enero de 2012 y enero de 2017. La información se obtuvo a partir de las fichas electrónicas de la Clínica Las Condes. Se describen procedencia, edad y sexo, características clínicas, hallazgos anatomopatológicos, métodos diagnósticos, tratamiento, evolución. Resultados: Total de 5 pacientes operados, 3 mujeres y 2 hombres. La edad promedio fue de 63 años, con rango de 33 años a 90 años de edad. 100% de los casos sin factores asociados. La presentación clínica más frecuente fue la obstrucción nasal unilateral, seguida por el dolor facial. Dos pacientes se presentaron con diagnóstico inicial, dos por recurrencia y uno por persistencia. En tres casos el tumor se origina de seno maxilar y en dos en seno etmoidal. Todos presentaron enfermedad avanzada, etapa IV y III. Tres pacientes histológicamente fueron de bajo grado y dos de alto grado. En los cinco casos el tratamiento primario fue quirúrgico, en el 60% endoscópico, 20% abierto y 20% combinado. En cuatro casos se usó radioterapia posoperatoria y en tres de éstos, quimioterapia concomitante. Todos se encuentran sin signos de recidiva tumoral en último control. Conclusiones: El carcinoma adenoide quístico de cavidad nasal y senos paranasales es bastante infrecuente, su incidencia es menor a 1/100.000 casos por año. Es más frecuente en mujeres entre 40 y 50 años. Se identifica más con su origen en el seno maxilar (50%) y de patrón cribiforme. Clínicamente se presenta en estadíos avanzados ya que en etapa precoz es asintomático o presenta clínica inespecífica inflamatoria. El diagnóstico se realiza con biopsia complementada con imagenología. El tratamiento más utilizado es la cirugía endoscópica o abierta asociado a radioterapia posoperatoria, a pesar de la cual, se presentan con alta recurrencia a largo plazo.

ABSTRACT Introduction: Adenoid Cystic Carcinoma is a neoplasm originating in exocrine glands throughout the body, mainly in the major salivary glands. In the nasal cavity and paranasal sinuses is rare and characterized by a high frequency of recurrence and distant metastasis after remission and despite its treatment. Aim: To describe characteristics of a series of patients with operated adenoid cystic carcinoma of the nasal cavity and paranasal sinuses. Material and method: Descriptive-retrospective study. Period January 2012 and January 2017. The information was obtained from the electronic tabs of the Las Condes Clinic. It describes origin, age and sex, clinical characteristics, anatomopathological findings, diagnostic methods, treatment, evolution. Results: Total 5 patients operated, 3 women and 2 men. The average age was 63 years, ranging from 33 years to 90 years of age. 100% of the cases without associated factors. The most frequent clinical presentation was unilateral nasal obstruction, followed by facial pain. 2 patients presented with initial diagnosis, 2 due to recurrence and 1 due to persistence. In 3 cases the tumor originates from the maxillary sinus and in 2 in the ethmoidal sinus. All had advanced disease, stage IV and III. 3 patients were histologically low grade and 2 high grade. In all 5 cases, the primary treatment was surgical, 60% endoscopic, 20% open and 20% combined. In 4 cases, postoperative radiotherapy was used and in 3 of this concomitant chemotherapy. All are without signs of tumor recurrence in the last control. Conclusion: Adenoid Cystic Carcinoma of the nasal cavity and paranasal sinuses is quite infrequent; its incidence is less than 1/100,000 cases per year. It is more common in women between 40 and 50 years. It is identified more with its origin in the maxillary sinus (50%) and cribriform pattern. Clinically it presents in advanced stages since at an early stage, it is asymptomatic or it presents nonspecific inflammatory clinic. Diagnosis is performed with biopsy supplemented with imaging. The most commonly used treatment is endoscopic or open surgery associated with postoperative radiotherapy, despite which, they present with high recurrence in the long term.

Uso del láser CO2 en la cirugía de la disfagia cricofaríngea: caso clínico / CO2 Laser use in the surgery of the cricopharyngeal muscle dysfunction: case report

La miotomía cricofaríngea es una técnica quirúrgica introducida hace años para el tratamiento de la disfagia asociada a disfunción del músculo cricofaríngeo con o sin divertículo de Zenker, mostrando resultados exitosos que revierten la sintomatologta y mejoran la calidad de vida del paciente. Con los avances científicos surge la cirugía láser endoscópica que permite ser una alternativa quirúrgica segura, viable y efectiva respecto a la miotomía clásica abierta, según diferentes series publicadas, mostrando disminuir los tiempos de anestesia, quirúrgico y de recuperación. En este artículo describimos un caso clínico, la técnica quirúrgica utilizada y los resultados en un paciente con disfagia por disfunción cricofaríngea con buen resultado posoperatorio.

Cricopharyngeal myotomy is a surgical technique introduced years ago for the treatment of dysphagia associated with cricopharyngeal muscle dysfunction with or without Zenker’s diverticulum, showing successful results that reverse the symptoms and improve the quality of life of patients. With scientific advances endoscopic laser surgery allows to be an open safe, feasible and effective for classical surgical myotomy alternative, according to various published series showing decreasing times anesthesia, surgical and recovery emerges. In this article we describe a case, the surgical technique used and results in a patient with dysphagia by cricopharyngeal dysfunction with good postoperative outcome.

Tumores del espacio parafaríngeo: revisión del tema / Parapharyngeal space tumors: review

Los tumores del espacio parafaríngeo son poco frecuentes, por lo tanto existe experiencia publicada limitada respecto a su diagnóstico y tratamiento. Por este motivo, representan un reto diagnóstico y terapéutico. En la mayoría de los casos se puede llegar a un diagnóstico con una adecuada anamnesis, examen físico, imagenología, y complementando con punción aspirativa con aguja fina. La diferenciación entre un tumor preestiloídeo de uno retroestiloídeo es fundamental para orientar el diagnóstico diferencial. El tratamiento de elección es la escisión quirúrgica, advirtiendo al paciente las posibles vías de abordaje, la comorbilidad asociada a cada una de estas vías, sobre todo a nivel de función de nervios craneanos, y la eventual necesidad de coadyuvancia en caso de requerirse.

Parapharyngeal space tumors are rare, so there is limited published experience regarding their diagnosis and treatment. Therefore, they represent a diagnostic and therapeutic challenge. In most cases, diagnosis can be made with an adequate anamnesis, physical examination, imaging, and the use of fine needle aspiration. Differentiation between prestyloid and poststyloid tumor is a key to guiding the differential diagnosis. The treatment of choice is surgical excision, warning the patient the possible surgical approaches, comorbidity associated with each of these pathways, especially at the level of function of cranial nerves, and the eventual need of coadjuvant treatment if required.

Speckle fields generated with binary diffusers and synthetic pupils implemented on a spatial light modulator.

Digitally controllable Gaussian speckle fields were experimentally generated by implementing binary diffusers and synthetic pupils on a liquid crystal spatial light modulator. The synthetic pupil comprises a Ronchi phase mask and a proper filtering of its diffraction orders. The binary diffuser is displayed inside an aperture defined onto the Ronchi phase mask. We demonstrated that this implementation replaces the need of using a ground glass and a physical pupil. In this way, the average speckle size, the statistical independence among the generated speckle patterns, and the average intensity distribution can be dynamically controlled.

Causa poco común de obstrucción nasosinusal recurrente: enfermedad de Rosai-Dorfman / Uncommon cause of recurrent sinus obstruction: Rosai-Dorfman disease

La enfermedad de Rosai-Dorfman corresponde a una enfermedad rara con menos de 1.000 casos reportados. Sus características clínicas corresponden a un aumento de volumen en ganglios cervicales, sin embargo, presenta compromiso extranodal como única manifestación entre el 25 por ciento y 50 por ciento de los casos. La ubicación nasosinusal ha sido reportada previamente, pese a ello, es más frecuente encontrarla en otras ubicaciones. El diagnóstico se basa en el estudio histopatológico encontrándose el fenómeno de emperipolesis, con células positivas a la proteína S-100. Esta enfermedad es frecuentemente confundida con neoplasias malignas, por lo que debe ser reconocida y sospechada. Se presenta el caso de un paciente de 15 años con historia obstrucción nasal de larga data, con múltiples recurrencias de la enfermedad de Rosai-Dorfman, demostrada mediante histopatología.

The Rosai-Dorfman disease corresponds to a rare disease with less than 1,000 reported cases. Their clinical characteristics correspond to a volume increase in cervical nodes, There is an extranodal involvement as the only manifestation of between 25 percent percent and 50 percent percent of cases. The sinonasal location has been previously reported. Diagnosis is based on histopathology with the phenomenon of emperipolesis with cells positive for S-100 protein. This disease is often confused with malignancy, so it must be recognized and suspected. A case of a patient 15 years with a history of longstanding nasal obstruction, with multiple recurrences of Rosai-Dorfman disease, demonstrated by histopathology.

Selection of antagonistic bacteria isolated from the Physalis peruviana rhizosphere against Fusarium oxysporum.

AIMS: Cape gooseberries (Physalis peruviana) have become increasingly important in Colombia for both domestic consumption and the international export market. Vascular wilting caused by Fusarium oxysporum is the most damaging disease to P. peruviana crops in Colombia. The control of this pathogen is mainly carried out by chemical and cultural practices, increasing production costs and generating resistance. Therefore, the objectives of this study were to test rhizobacteria isolates from P. peruviana rhizosphere against F. oxysporum under in vitro and in vivo conditions. METHODS AND RESULTS: Over 120 strains were isolated, and five were selected for their high inhibition of F. oxysporum growth and conidia production under in vitro conditions. These strains inhibited growth by 41-58% and reduced three- to fivefold conidia production. In the in vivo assays, all the tested isolates significantly reduced fungal pathogenicity in terms of virulence. Isolate B-3.4 was the most efficient in delaying the onset of the first symptoms. All isolates were identified as belonging to the genus Pseudomonas except for A-19 (Bacillus sp.). CONCLUSIONS: Our results confirmed that there are prospective rhizobacteria strains that can be used as biological control agents; some of them being able to inhibit in vitro F. oxysporum growth and sporulation. SIGNIFICANCE AND IMPACT OF THE STUDY: Incorporating these bacteria into biological control strategies for the disease that causes high economical losses in the second most exported fruit from Colombia would result in a reduced impact on environment and economy.

Cuerpos extraños en vía aérea / Foreign body in airway

Los cuerpos extraños de la vía aérea constituyen un evento muy peligroso especialmente en niños, constituye la causa principal de muerte accidental en menores de un año y el riesgo se mantiene hasta los tres años. La prevención y el rápido diagnóstico puede salvar muchas vidas. La clínica en general puede ser muy variable desde el momento dramático de la inhalación con sofocación y ahogo hasta un examen normal una vez pasado el episodio agudo. Por esta razón el índice de sospecha y una buena historia a las personas que acompañan a los niños es fundamental.

Foreign body inhalation is a dangerous event, specially in children. It is the most common cause of accidental death in children under 1 year and the risk remains up to age 3 years. Prevention and rapid diagnosis can be life saving. The clinic presentation and radiologic findings may be variable, since the dramatic event of sudden sofocation and choking until normal exam upon the acute presentation has stopped. A good history and high index of suspicious is paramount.

The fractional urinary fluoride excretion of adults consuming naturally and artificially fluoridated water and the influence of water hardness: a randomized trial.

AIMS: To assess whether there was any significant difference in the average fractional urinary fluoride excretion (FUFE) values among adults consuming (NaF) fluoridated Ca-free water (reference water), naturally fluoridated hard water and an artificially (H2SiF6) fluoridated soft water. DESIGN: Sixty adult females (N=20 for each treatment) participated in this randomized, double-blind trial. The experimental design of this study provided an indirect estimation of the fluoride absorption in different types of water through the assessment of the fractional urinary fluoride excretion of volunteers. RESULTS: Average daily FUFE values (daily amount of fluoride excreted in urine/daily total fluoride intake) were not significantly different between the three treatments (Kruskal-Wallis; p = 0.62). The average 24-hour FUFE value (n=60) was 0.69; 95% C.I. 0.65-0.73. CONCLUSIONS: The results of this study suggest that the absorption of fluoride is not affected by water hardness.

Tratamiento quirúrgico del ronquido y la apnea obstructiva del sueño / Snoring and sleep apnea syndrome: surgical treatment

La roncopatía y la apnea obstructiva del sueño son problemas muy comunes en la población general. Su causa es un colapso de la vía aérea superior en cualquiera de sus niveles, nasal, orofaringeo y/o hipofaringeo (base de lengua). La roncopatía es un problema fundamentalmente social. Por otro lado la apnea obstructiva del sueño constituye un problema de riesgo médico por la mayor tasa de accidentes de tráfico, accidentes cardiovasculares, etc. Si bien es cierto ambas entidades son de resolución médica mediante el uso de CPAP, se han descrito un sinnúmero de técnicas quirúrgicas desde 1981 con el fin de ayudar a aquellos pacientes que no desean o no toleran el uso de CPAP.

Snoring and Sleep Apnea Syndrom are common disorders among general population. Both entities are produced by collapse of the Upper airway usually at multiples levels, nose, oropharinx and /or hypopharinx (base of tongue). Whereas snoring is social problem, sleep apnea syndrome is a medical entity because of the higher rates of traffic accidents and cardiovascular diseases. The current mainstay for treating these disorders is the CPAP, however many surgical procedures have been described since 1981 in order to help a group of patients who cannot or will not accept CPAP as a permanent form of management.

Genotypic and technological characterization of Lactococcus lactis isolates involved in processing of artisanal Manchego cheese.

AIMS: Genotypic and technological characterization of wild lactococci isolated from artisanal Manchego cheese during the ripening process for selection of suitable starter cultures. METHODS AND RESULTS: A total of 114 isolates of lactococci were typed using randomly amplified polymorphic DNA-polymerase chain reaction (RAPD-PCR). Sixteen distinct RAPD-PCR patterns, at a similarity level of 73%, were obtained. On the basis of species-specific PCR reaction, the isolates were assigned to the species Lactococcus lactis subsp. lactis and Lactococcus lactis subsp. cremoris with L. lactis subsp. lactis being predominant at both dairies. Twenty-six isolates were technologically characterized to select those with the best properties. Most of them showed good technological properties although some could produce tyramine. CONCLUSIONS: The presence of coincident genotypes at both dairies has been demonstrated, which would suggest that they are well adapted to the Manchego cheese environment. Interesting differences were found in the technological characterization and the potential role of autochthonous lactococci strains as starter culture has been displayed. SIGNIFICANCE AND IMPACT OF THE STUDY: The great economic importance of Manchego cheese encouraged a deeper knowledge of its microbiota, to select strains with the best properties to use as starter cultures in industrial Manchego cheeses, preserving the autochthonous characteristics.

Fractional urinary fluoride excretion of young female adults during the diurnal and nocturnal periods.

OBJECTIVES: This study aimed to confirm a previously obtained value for the fractional urinary fluoride excretion (FUFE) over a 24-hour period in adults and to assess whether there are significant differences between FUFE measured during the diurnal (7 a.m. and 6 p.m.) and the subsequent nocturnal (6 p.m. until 7 a.m. of the following day) periods. METHODS: Urine was collected over 24 h from 60 healthy female volunteers residing in Santiago, Chile. The individuals' fluoride intakes over the diurnal and nocturnal periods were calculated from their corresponding F ingestion, measured by dietary analysis. Separate urine collections during both periods were obtained from each volunteer. The fluoride concentrations were measured with a fluoride-ion-selective electrode either directly (urine, water and beverages) or after sample treatment with the microdiffusion technique (food). RESULTS: The average 24-hour FUFE value was 0.69, with a 95% CI of 0.65-0.72, while the average FUFE for the diurnal period was 0.46 (95% CI: 0.42-0.50), and the corresponding result for the nocturnal period showed a significantly higher (paired t test, p < 0.0001) amount of 1.09 (95% CI: 0.97-1.22). CONCLUSIONS: A recently published result for the daily FUFE value (0.71) in adults was confirmed. The diurnal average FUFE value is significantly lower than the average nocturnal one. Accepting that approximately 10% of the fluoride intake is not absorbed, the daily fluoride retention can be preliminarily estimated as 20% of the ingested fluoride.

Tumores de cabeza y cuello / Head and neck tumors

Los tumores de cabeza y cuello corresponden a un heterogéneo grupo de enfermedades, destacando entre ellas el carcinoma epidermoide de laringe, faringe y cavidad oral, así como las neoplasias glandulares (tiroides y glándulas salivales). Constituyen una patología altamente desafiante, considerando la complejidad anatómica de la región cérvico-facial y las repercusiones funcionales y estéticas que pueden producir tanto la enfermedad como su tratamiento. Estos tumores se manifiestan clínicamente como masas palpables o por la producción de síntomas persistentes en la vía aéreo-digestiva superior. La imagenología y los estudios endoscópicos complementan la evaluación del paciente; la histopatología es esencial para determinar el diagnóstico definitivo. El manejo de los tumores de cabeza y cuello debe estar a cargo de equipos multidisciplinarios, siendo la cirugía y la radioterapia los pilares del tratamiento. El pronóstico de esta enfermedad está determinado, principalmente, por el tipo histológico y el estadio tumoral.

Paragangliomas de cabeza y cuello / Parangangliomas of the head and neck

Los parangangliomas son tumores altamente vascularizados que se originan de células provenientes de la cresta neural. El tratamiento de elección es la resección quirúrgica completa, lo cual se ve dificultado por su abundante irrigación y por su estrecha relación anatómica con importantes estructuras vásculo-nerviosas. En el presente estudio se revisa retrospectivamenete la experiencia del Departamento de Otorrinolaringología de Clínica Las Condes en el manejo quirúrgico de estas neoplasias. Entre los años 1998 y 2003 se trataron 5 pacientes portadores de paragangliomas de cabeza y cuello: un glomus yugular (GY), 2 glomus carotídeo (GC) y 2 glomus timpánicos (GT). El estudio imagenológico consistió en tomografía computarizada (TC) para todos los casos, complementada con resonancia nuclear magnética (RNM) y/o angiografía en algunos pacientes. El abordaje quirúrgico fue el indicado para cada lesión: timpanotomía retroauricular (GT), cervicotomía (GC) y abordaje infratemporal tipo A de Fisch (GY). En todos se logró una resección tumoral completa, sin presentarse complicaciones perioperatorias de consideración ni recurrencias hasta la fecha. Contando con un adecuado estudio imagenológico y una cuidadosa planificación quirúrgica, la resección de los paragangliomas de cabeza y cuello puede realizarse con un bajo índice de complicaciones, reservando la radioterapia como alternativa terapéutica únicamente en aquellos casos inoperables.

The fractional urinary fluoride excretion in young children under stable fluoride intake conditions.

The purpose of this study was to determine the fraction of the total daily fluoride intake that is excreted through the urine (FUEF) of children aged 3-5 years under usual intake conditions. Participating children were residents of an area with a fluoride (F) concentration of 0.5-0.6 mg/L in their drinking water. Assessments were made on two successive 24-h periods on 20 children, measuring the total amount of fluoride ingested through liquid and food consumption, and from ingestion of fluoridated toothpaste (500 microg F/g), together with the determination of the amount of fluoride excreted through urine. Fluoride retention was also estimated assuming a constant average F fraction of 10% excreted through faeces. It was found that the average proportion of liquids, solid foods, and toothpaste to the daily fluoride intake (1.02-mg F/day on average) were 40.8, 34.6, and 24.5%, respectively. The average FUEF value was 35.5% (95% C.I.=31.7-39.3%), and the estimated fractional F retention was 54.5%. The present data suggest a slight relationship between FUEF values and the inverse of the daily fluoride dose (1/dose) (r=0.513; P=0.021). When the present results are combined with those from previous studies on F-retention and urinary excretion, the correlation between both FUEF and fractional retention and 1/dose are very strong and highly significant (r=0.98, P<0.0001, and r=-0.986, P<0.0001, respectively). A possible mechanism is suggested in order to explain this latter finding. The potential usefulness of the current FUEF value for the estimation of daily F intake (or dose) from urinary F excretion data is also discussed.

Tumores parafaríngeos en niños: descripción de dos casos clínicos / Parapharyngeal tumors in pediatrics: 2 clinical cases

Se presentan dos casos clínicos de tumores parafaríngeos de niños tratados en el Servicio de ORL del Hospital Regional Valdivia. El primero corresponde a un coristoma que histológicamente constituye tejido neuroglial maduro el cual fue tratado con cirugía exclusiva. El segundo caso es un Rabdomiosarcoma embrionario que fue sometido a una resección con quimioterapia y radioterapia según protocolo y a una cirugía de rescate por una recidiva local. Se revisa la literatura con especial énfasis a la anatomía, técnica quirúgica e histología de los tumores que afectan el espacio parafaríngeo

Estimation of the fraction of an ingested dose of fluoride excreted through urine in pre-school children.

OBJECTIVE: To determine the fraction of an ingested fluoride dose of 1 mg in 50 mL orange juice that is excreted through the urine (FUEF) of children aged 3-5 years. METHODS: Eighty-eight controlled determinations involving 24-hour urinary collections from a total of 48 children were carried out during consecutive control and test days. Net fluoride urinary excretion due to the ingested dose was calculated as the difference between the total amount of fluoride excreted by each child on test and control days. RESULTS: Excretion of the fluoride ingested from the single fluoride dose presented an average value of 30.7% (95% CI: 28.9-32.5%). No significant associations were found between individual FUEF values with either anthropometrical variables or urinary pH values. The average FUEF value found in the present study lies between previously reported values for infants and young adults. The epidemiological usefulness of the FUEF values in estimating daily fluoride dose in pre-school children is discussed.