Risk factors for hypocalcemia after total thyroidectomy.

BACKGROUND: Hypocalcemia is a common complication of total thyroidectomy; transient hypocalcemia has been reported in up to 68% of the patients. MATERIALS AND METHODS: Chart review of all patients undergoing total thyroidectomy from 2016 to 2020. Clinical, biochemical, and pathological information was registered. We sought correlations between the different variables and the occurrence of post-operative hypocalcemia. This is a retrospective study carried out at a tertiary care teaching hospital. OBJECTIVES: The aim of the study was to ascertain the incidence of hypocalcemia after thyroidectomy and to establish potential clinical and pathological risk factors for its development. RESULTS: Three hundred and thirty-seven patients were included in this study (78% female), with a median age of 47 years. The majority (75%) harbored thyroid neoplasms. Post-operative hypocalcemia developed in 43 patients (12.7%). On bivariate analysis, the most significant risk factor was an intraoperative injury of the parathyroid glands (OR = 2.49, 95% CI = 1.11-5.59), followed by a surgical time > 2.5 h (OR = 2.0, 95% CI = 1.03-4.19), concomitant lymph node dissection (OR = 2.45, 95% CI = 1.2-4.9), and placement of drains (OR = 2.40, 95% CI = 1.19-4.87). Only parathyroid injury remained statistically significant on multivariable analysis. CONCLUSIONS: The most significant risk factor for the development of post-operative hypocalcemia after thyroidectomy is injury of the parathyroid glands, which is usually noticed by the surgeon.

INTRODUCCIÓN: La hipocalcemia es una complicación común después de una tiroidectomía; la hipocalcemia transitoria ha sido reportada hasta en el 68% de los pacientes posoperados. MATERIALS Y MÉTODOS: Revisión de expedientes de pacientes a los cuales se les realizo una tiroidectomía total entre el 2016 y 2020. La información clínica, bioquímica y patológica fue recopilada. Se busco una correlación entre las variables y el desarrollo de hipocalcemia. Es un estudio retrospectivo en un hospital escuela de atención terciaria. OBJETIVOS: Determinar la incidencia de hipocalcemia pos-tiroidectomía y establecer posibles factores de riesgo clínicos y patológicos para desarrollarlo. RESULTADOS: Se incluyeron 337 pacientes en este estudio (78% mujeres), con edad media de 47 años. La mayoría (75%) presentaron neoplasias tiroideas. Cuarenta y tres pacientes desarrollaron hipocalcemia (12.7%). En el análisis bivariado el factor de riesgo mas importante fue la lesión de paratiroides (RM = 2.49, IC95% = 1.11-5.59), seguido por un tiempo quirúrgico > 2.5 horas (RM = 2.0, IC 95% = 1.03­4.19), disección linfática (RM = 2.45, IC95% = 1.2-4.9) y la colocación de drenajes (RM = 2.40, IC95% = 1.19-4.87). Únicamente la lesión de paratiroides mantuvo significancia en el análisis multivariado. CONCLUSIONES: La lesión de paratiroides es el factor de riesgo mas grande para desarrollar hipocalcemia y generalmente es identificado por el cirujano.

Location and Vascular Classification of 188 parathyroid glands in New Zealand White Rabbits / [Localização e Classificação Vascular de 188 glândulas paratireoidianas em coelhos brancos da Nova Zelândia]

The function and protection of the parathyroid glands are increasingly popular research topics. New Zealand white rabbits are the most commonly used animal model of parathyroid ischemia. However, information on the vasculature of their parathyroid glands is limited. We used 94 healthy New Zealand white rabbits, 3-4 months of age and 2-3kg in weight, for exploration of the parathyroid glands, which were stained using hematoxylin and eosin (HE) after removal. The following types were classified according to the relationship between the position of the inferior parathyroid gland and the thyroid: Type A, Close Type, Type B, and Distant Type. There were 188 cases, 4 where the inferior parathyroid glands were located near the dorsal side of thyroid (2.13%), 8 where the inferior parathyroid glands were located superior to the upper pole of the thyroid (4.26%), 20 where the inferior parathyroid glands were located parallel to the thyroid (10.64%), and 155 cases where the inferior parathyroid glands were located inferior to the lower pole of thyroid (82.45%). Identifying the location and classifying the vasculature of the parathyroid glands in New Zealand white rabbits will provide an anatomical model to assist in future research.(AU)

A função e proteção das glândulas paratireoidianas é um tópico de pesquisa cada vez mais popular. Coelhos brancos da Nova Zelândia são o modelo animal mais comumente usada para isquemia da paratireóide. Porém, informação sobre a vasculatura de suas glândulas paratireóides é limitada. Foram usados 94 coelhos brancos da Nova Zelândia saudáveis, com 3-4 meses de idade, 2-3kg de peso, para exploração das glândulas paratireóides, que foram coradas com hematoxilina e eosina (HE) após a remoção. Os seguintes tipos foram classificados de acordo com a relação entre a posição da glândula paratireoidiana inferior e a tireoide: Tipo A, Tipo Próximo, Tipo B e Tipo Distante. Houve 188 casos, 4 em que as glândulas paratireoidianas inferiores estavam localizadas próximas ao lado dorsal da tireoide (2.13%), 8 onde as glândulas paratireoidianas inferiores estavam localizadas superiores ao polo superior da tireoide (4.26%), 20 onde as glândulas paratireoidianas inferiores estavam localizadas paralelo à tireoide (10.64%) e 155 casos em que as glândulas paratireoidianas inferiores estavam localizadas inferiores ao polo inferior da tireoide (82.45%). A identificação da localização e a classificação da vasculatura das glândulas paratireóides em coelhos brancos da Nova Zelândia fornecerão um modelo anatômico para auxiliar em pesquisas futuras.(AU)

Parathyroid hormone levels after parathyroidectomy for secondary hyperparathyroidism

SUMMARY OBJECTIVE: The parathormone level after parathyroidectomy in dialysis patients are of interest. Low levels may require cryopreserved tissue implantation; however, the resection is necessary in case of recurrence. We analyzed post parathyroidectomy parathormone levels in renal hyperparathyroidism. METHODS: Prospective observation of postoperative parathormone levels over defined periods in a cohort of dialysis patients that underwent total parathyroidectomy and immediate forearm autograft from 2008 to 2010, at a single tertiary care hospital. RESULTS: Of 33 patients, parathormone levels until 36 months could be divided into four patterns. Patients with stable function (Pattern 1) show relatively constant levels after two months (67% of the cases). Early function and later failure (Pattern 2) were an initial function with marked parathormone reduction before one year (18%). Graft recurrence (Pattern 3) showed a progressive increase of parathormone in four cases (12%). Complete graft failure (Pattern 4) was a nonfunctioning implant at any period, which was observed in one patient (3%). Parathormone levels of Pattern 3 became statistically different of Pattern 1 at 36 months. CONCLUSIONS: Patients that underwent the total parathyroidectomy and autograft present four different graft function patterns with a possible varied therapeutic management.

Hiperparatiroidismo primario: conceptos para el cirujano general / Primary hyperparathyroidism: concepts for the general surgeon

Durante las últimas décadas, la incidencia del hiperparatiroidismo primario ha venido en aumento, muy probablemente relacionado con la mayor accesibilidad a los estudios diagnósticos; sin embargo, la forma más común de presentación clínica del hiperparatiroidismo primario es asintomática, en más del 80 % de los pacientes. En la actualidad, es menos frecuente el diagnóstico por las complicaciones renales (urolitiasis) u óseas (osteítis fibrosa quística) asociadas. Un tumor benigno de la glándula paratiroides (adenoma único), es la principal causa de esta enfermedad. Por tanto, su tratamiento usualmente es quirúrgico. A pesar de ello, no es frecuente el manejo de esta patología por el cirujano general. En este artículo se revisan conceptos claves para el diagnóstico y manejo de esta enfermedad para el médico residente y especialista en Cirugía general

During the last decades, the incidence of primary hyperparathyroidism has been increasing, most probably related to the greater accessibility to diagnostic studies; however, the most common form of clinical presentation of primary hyperparathyroidism is asymptomatic in more than 80% of patients. Diagnosis is less frequent due to associated renal (urolithiasis) or bone (osteitis fibrosa cystica) complications. A benign tumor of the parathyroid gland (single adenoma) is the main cause of this disease. Therefore, its treatment is usually surgical. Despite this, the management of this pathology by the general surgeon is not frequent. This article reviews key concepts for the diagnosis and management of this disease for the resident physician and specialist in General Surgery

[Ectopic hyperparathyroidism. Detection of mediastinal localization]. / Hiperparatiroidismo ectópico. Detección de la localización mediastinal.

The ectopic parathyroid tissue is a frequent cause of recurrent hyperparathyroidism (HPT), accounting 16% in primary HPT and 14% in secondary cases. Although intrathoracic ectopic glands represent 25-35% of all ectopic cases, only 2% requires thoracic surgery. The aim of this study is to report a case series of patients with ectopic mediastinal HPT treated by thoracic approach in a private institution in Argentina. This is a retrospective analysis from January 2006 to June 2019. All patients diagnosed with ectopic hyperparathyroidism who required a thoracic surgical approach were included. During this period, 728 patients with primary HPT and secondary HPT were treated. Six with primary HPT and 3 with secondary HPT required a thoracic approach. Six video-assisted thoracoscopy surgeries (VATS) and 3 sternotomies were performed. None of them presented serious posoperative complications. Frozen section biopsy was used in all cases. iPTH was measured in 8 cases, with a mean drop of 65% after 15 minutes. Final pathology reports confirmed 5 adenomas and 4 hyperplasias. Our case series reported an incidence of 1.65% (12/728) mediastinal parathyroids, while 1.24% (9/728) received surgical treatment at our institution. Intraoperative frozen section and PTHi are useful to confirm the diagnosis and to avoid recurrences. Although VATS is a safe and efficient treatment option, it depends on surgical training and availability. In terms of diagnostic imaging resources, sestamibi remains the current gold standard. However, 18F-choline PET/CT may arise as a new diagnostic tool. The possibility of obtaining evidence-based conclusions requires studies with higher number of patients.

El tejido paratiroideo ectópico es una causa frecuente de recurrencia del hiperparatiroidismo (HPT) siendo de 16% en primarios y 14% en secundarios. La localización intratorácica representa el 20-35%, pero solo un 2% requiere una cirugía torácica. El objetivo fue analizar una cohorte de pacientes con diagnóstico de HPT mediastinal operados en un hospital de alta complejidad de Argentina. Se realizó un estudio retrospectivo de todos los operados por HPT entre enero de 2006 y julio 2019 en ese hospital. Se incluyeron aquellos que requirieron acceso torácico por HPT ectópico. En este período se trataron 728 pacientes con HPT primario y secundario. Seis con primario y 3 con secundario requirieron cirugía torácica. Se realizaron 6 videotoracoscopias (VATS) y 3 esternotomías, sin complicaciones graves. Se utilizó biopsia por congelación en todos y dosaje de paratohormona intraoperatoria (PTHi) en 8 casos, que descendió en promedio 65% respecto al valor basal. Se confirmaron 5 adenomas y 4 hiperplasias. La enfermedad paratiroi dea mediastinal representó el 1.65% (12/728), mientras que recibieron tratamiento quirúrgico en nuestra institución 1.24% (9/728). La biopsia por congelación y el descenso de PTHi resultan útiles para confirmar el foco y eventualmente disminuir el riesgo de recurrencia. La VATS es segura pero depende del entrenamiento y de la disponibilidad en el medio asistencial. Si bien el sestamibi es el método con mayor sensibilidad, se propone el uso de 18F-colina PET/TC ante la sospecha de HPT ectópico. La posibilidad de obtener conclusiones basadas en la evidencia requiere de estudios con mayor número de pacientes.

Hiperparatiroidismo ectópico: Detección de la localización mediastinal / Ectopic hyperparathyroidism. Detection of mediastinal localization

El tejido paratiroideo ectópico es una causa frecuente de recurrencia del hiperparatiroidismo (HPT) siendo de 16% en primarios y 14% en secundarios. La localización intratorácica representa el 20-35%, pero solo un 2% requiere una cirugía torácica. El objetivo fue analizar una cohorte de pacientes con diagnóstico de HPT mediastinal operados en un hospital de alta complejidad de Argentina. Se realizó un estudio retrospectivo de todos los operados por HPT entre enero de 2006 y julio 2019 en ese hospital. Se incluyeron aquellos que requirieron acceso torácico por HPT ectópico. En este período se trataron 728 pacientes con HPT primario y secundario. Seis con primario y 3 con secundario requirieron cirugía torácica. Se realizaron 6 videotoracoscopias (VATS) y 3 esternotomías, sin complicaciones graves. Se utilizó biopsia por congelación en todos y dosaje de paratohormona intraoperatoria (PTHi) en 8 casos, que descendió en promedio 65% respecto al valor basal. Se confirmaron 5 adenomas y 4 hiperplasias. La enfermedad paratiroi dea mediastinal representó el 1.65% (12/728), mientras que recibieron tratamiento quirúrgico en nuestra institución 1.24% (9/728). La biopsia por congelación y el descenso de PTHi resultan útiles para confirmar el foco y eventualmente disminuir el riesgo de recurrencia. La VATS es segura pero depende del entrenamiento y de la disponibilidad en el medio asistencial. Si bien el sestamibi es el método con mayor sensibilidad, se propone el uso de 18F-colina PET/TC ante la sospecha de HPT ectópico. La posibilidad de obtener conclusiones basadas en la evidencia requiere de estudios con mayor número de pacientes.

The ectopic parathyroid tissue is a frequent cause of recurrent hyperparathyroidism (HPT), accounting 16% in primary HPT and 14% in secondary cases. Although intrathoracic ectopic glands represent 25-35% of all ectopic cases, only 2% requires thoracic surgery. The aim of this study is to report a case series of patients with ectopic mediastinal HPT treated by thoracic approach in a private institution in Argentina. This is a retrospective analysis from January 2006 to June 2019. All patients diagnosed with ectopic hyperparathyroidism who required a thoracic surgical approach were included. During this period, 728 patients with primary HPT and secondary HPT were treated. Six with primary HPT and 3 with secondary HPT required a thoracic approach. Six video-assisted thoracoscopy surgeries (VATS) and 3 sternotomies were performed. None of them presented serious posoperative complications. Frozen section biopsy was used in all cases. iPTH was measured in 8 cases, with a mean drop of 65% after 15 minutes. Final pathology reports confirmed 5 adenomas and 4 hyperplasias. Our case series reported an incidence of 1.65% (12/728) mediastinal parathyroids, while 1.24% (9/728) received surgical treatment at our institution. Intraoperative frozen section and PTHi are useful to confirm the diagnosis and to avoid recurrences. Although VATS is a safe and efficient treatment option, it depends on surgical training and availability. In terms of diagnostic imaging resources, sestamibi remains the current gold standard. However, 18F-choline PET/CT may arise as a new diagnostic tool. The possibility of obtaining evidence-based conclusions requires studies with higher number of patients.

Resection of supernumerary mediastinal parathyroid as a treatment for persistent secondary hyperparathyroidism. / Resección de paratiroides mediastinal supernumeraria como tratamiento del hiperparatiroidismo secundario persistente.

BACKGROUND: Secondary refractory hyperparathyroidism (SHPT) is usually resolved with total parathyroidectomy. On the other hand, SHPT is associated with persistent hyperparathyroidism as a result of inadequate resection of the parathyroid tissue or by a fifth gland not previously detected. The objective of this work is to present the case of a patient with persistent SHPT and the surgical strategy used for the resection of a hyperfunctional ectopic parathyroid in the thorax. CLINICAL CASE: 48-year-old female, with a history of chronic kidney disease with persistent SHPT, as well as subtotal parathyroidectomy, subsequent resection of parathyroid remnants twice. She was treated with medical management without obtaining adequate response. Previous location of hypercaptant lesion by single photon emission computed tomography, the patient underwent a sternotomy with 3 × 2 cm mediastinal ectopic parathyroid fixed to aortic root. The patient evolved satisfactorily with a decrease in parathyroid hormone levels, with a 18-month follow-up of the procedure with normal paratohormone values and entered the renal transplant protocol while waiting for a donor. CONCLUSION: Sternotomy is a safe approach to perform parathyroidectomy of the ectopic gland, provided that it is well identified the site of the lesion and there are specific conditions appropriate to perform the procedure.

INTRODUCCIÓN: El hiperparatiroidismo secundario (HPS) refractario suele resolverse con paratiroidectomía total. Por otro lado, el HPS se asocia a hiperparatiroidismo persistente como resultado de una resección inadecuada del tejido paratiroideo o por una quinta glándula no detectada previamente. Se presenta el caso de una paciente con HPS persistente con la estrategia quirúrgica utilizada para la resección de una paratiroides ectópica hiperfuncionante en el tórax. CASO CLÍNICO: Mujer de 48 años con antecedente de enfermedad renal crónica con HPS persistente, paratiroidectomía subtotal y posterior resección de remanente de paratiroides en dos ocasiones. Se mantuvo con manejo médico sin obtener adecuada respuesta. Previa localización de una lesión hipercaptante por tomografía computarizada por emisión de fotón único se sometió a esternotomía con resección de paratiroides ectópica mediastinal de 3 × 2 cm, fija a la raíz aórtica. La paciente evolucionó satisfactoriamente, con descenso de la hormona paratiroidea. En seguimiento a 18 meses del procedimiento se mantiene con valores normales de hormona paratiroidea e ingresó a protocolo de trasplante renal a la espera de donador. CONCLUSIÓN: La esternotomía es un abordaje seguro para realizar la paratiroidectomía de la glándula ectópica, siempre y cuando se tenga bien identificado el sitio de la lesión y existan condiciones clínicas adecuadas para realizar el procedimiento.

Adenoma paratiroideo mediastínico como causa de hiperparatiroidismo primario / Mediastinal parathyroid adenoma as a cause of primary hyperparathyroidism

Resumen Las glándulas paratiroides participan en la regulación de las concentraciones de calcio al producir parathormona como respuesta a la hipocalcemia. Los adenomas paratiroideos, que rara vez se encuentran en mediastino, son la causa más importante de hiperparatiroidismo primario, una enfermedad rara con manifestaciones clínicas graves y que se diagnostica por la com binación de concentraciones elevadas de calcio sérico y paratohormona. Se considera que el adenoma paratiroideo ectópico se deriva de la migra ción de las glándulas paratiroides al mediastino y se conoce como una causa importante del fracaso de la exploración primaria del hiperparatiroi dismo primario. Se presenta un caso de adenoma paratiroideo mediastíni co en una mujer de 48 años que llevó a la aparición de hiperparatiroidismo primario. El adenoma se extirpó mediante esternotomía media total.

Abstract Parathyroid glands participate in regulation of calcium concentrations by producing parathormone in response to hypocalcemia. Parathyroid adeno mas, which are rarely found in the mediastinum, are the most important cause of primary hyperparathyroidism, which is a rare disease with serious clinical manifestations and is diagnosed by combination of high concentrations of serum calcium and parathormone. It is considered that ectopic parathyroid adenoma is derived from the migration of the parathyroid glands to the mediastinum and is known as an important cause of the failure of primary exploration of primary hyperparathyroidism. We present a case of medias tinal parathyroid adenoma in a 48-year-old woman that led to appearance of primary hyperparathyroidism. Adenoma was removed by total median sternotomy.

Imágenes de adenomas paratiroideos ectópicos. Una revisión de la literatura / Imaging Ectopic Parathyroid Adenomas. A Literature Review

Objetivos: 1) Revisar la anatomía y epidemiología de los adenomas paratiroideos ectópicos (APE); 2) resumir el papel de las modalidades de imagen relevantes en su localización; y 3) revisar brevemente los enfoques quirúrgicos para los mismos. Métodos: Reseña literaria de artículos publicados en inglés desde 1984 hasta agosto de 2017. Resultados: El resumen de la literatura indica que la prevalencia de APE es de, aproximadamente, el 20 % en pacientes con hiperparatiroidismo primario que no han sido intervenidos quirúrgicamente, pero en pacientes reintervenidos es tan alta que alcanza el 66 %. Los APE pueden estar localizados en cualquier lugar, desde la bifurcación de la carótida hasta la ventana aortopulmonar. El ultrasonido tiene una agudeza diagnóstica limitada en su identificación, excepto para los que están localizados cerca de la glándula tiroides y al ligamento tirotímico. Requiere gran experiencia del operador. Si se comparan las técnicas de gammagrafía Sestamibi- 99mTc de fase dual, la imagen híbrida con tomografía computarizada de emisión de fotón simple (SPECT) y con tomografía computarizada (TC), la técnica SPECT/TC es superior a la gammagrafía planar o SPECT en la localización de los APE. La TC en cuatro dimensiones (4DTC) delinea con precisión las relaciones anatómicas importantes y es altamente sensible para la localización de los APE. Aunque la 4DTC requiere radiación, medio de contraste intravenoso yodado y experiencia del lector, provee buena información para detectar lesiones en varios sitios ectópicos y guiar el abordaje quirúrgico. Los APE frecuentemente requieren enfoques quirúrgicos alternativos. Se puede intentar una nueva paratiroidectomía en pacientes que han sido previamente sometidos a una exploración bilateral del cuello, por un cirujano experimentado, una vez que la lesión se localice mediante dos modalidades de imágenes. La remoción de la enfermedad no localizada requiere una exploración cuidadosa y sistemática de las localizaciones superiores e inferiores de las glándulas. Conclusión: Los APE plantean desafíos tanto para su localización como para la extirpación quirúrgica. Con el fin de obtener resultados óptimos se requiere contar con la experiencia de un alto número de pacientes y una atención multidisciplinaria.

Objective: (1) To review the anatomy and epidemiology of ectopic parathyroid adenomas (EPAs), (2) summarize the role of relevant imaging modalities in the localization of EPAs, and (3) briefly review surgical approaches for EPAs. Methods: Literature review of published English-language articles from 1984 through August 2017. Results: Summary of the literature indicates that the prevalence of EPA is approximately 20% in unexplored patients with primary hyperparathyroidism, but it is as high as 66% in re-operative patients. EPAs may be located anywhere from the carotid bifurcation to the aortopulmonary window. Ultrasound has limited accuracy in identifying EPAs except near the thyroid and thyrothymic ligament and requires expert experience from the user. Among dual-phase 99mTc sestamibi scintigraphy techniques, hybrid imaging with both singlephoton emission computed tomography (SPECT) and computed tomography (CT), (SPECT/CT) is superior to planar scintigraphy or SPECT alone at localizing EPAs. Four-dimensional computed tomography (4DCT) precisely delineates important anatomic relationships and is highly sensitive in localizing EPAs. Although 4DCT requires radiation, intravenous iodinated contrast, and reader experience, it is well-equipped to detect lesions at various ectopic sites and guide the surgical approach. EPAs frequently require alternative surgical approaches. Re-operative parathyroidectomy may be attempted in patients having previously undergone bilateral neck exploration by an experienced surgeon once the lesion is colocalized by 2 repeat imaging modalities. Removal of nonlocalized disease requires a careful and systematic exploration of superior and inferior gland locations. Conclusion: EPAs pose challenges during both localization and surgical removal. High-volume experience and multidisciplinary care are necessary for optimal outcomes.

Evaluación mediante ultrasonido de las glándulas paratiroides / Ultrasound Evaluation of the Parathyroid Glands

La principal indicación para el estudio de las glándulas paratiroides son las masas y, específicamente, la sospecha de adenomas, que son la patología más frecuente. Entre las diferentes modalidades diagnósticas disponibles, las de mayor sensibilidad para su detección son el ultrasonido y la gammagrafía con sestamibi, que en conjunto alcanzan la mayor especificidad para el diagnóstico. La evaluación mediante ultrasonido de las glándulas paratiroides tradicionalmente se ha considerado compleja y operador-dependiente; sin embargo, con las nuevas tecnologías de alta resolución es mucho más sencilla y nos obligamos a identificarlas en forma rutinaria, sean normales o patológicas. En este trabajo se hace una revisión sobre la anatomía normal, las técnicas de exploración y los hallazgos normales y anormales en ultrasonido de paratiroides para realizar un abordaje sencillo en la práctica diaria.

The main indication for the study of the parathyroid glands is the suspicion of masses and specifically the suspicion of adenomas, which are the most frequent pathology. Among the different diagnostic modalities available, the most sensitive for detection are ultrasound and Sestamibi scintigraphy, which together achieve the highest specificity for diagnosis. Ultrasound evaluation of the parathyroid glands has traditionally been considered complex and operator dependent, but with the new high resolution technologies it is much simpler and we are obliged to identify them routinely, whether normal or pathological. In the present work, a review is made on the normal anatomy, exploration techniques and normal and abnormal findings in parathyroid ultrasound to perform a simple and practical approach to daily practice.

Tratamento cirúrgico do hiperparatireoidismo secundário: revisão sistematizada da literatura / Surgical treatment of secondary hyperparathyroidism: a systematic review of the literature

O hiperparatireoidismo (HPT) secundário tem prevalência elevada em doentes renais crônicos. Decorre de alterações na homeostase mineral, principalmente do cálcio, que estimulam as glândulas paratireoides, com aumento na secreção de paratormônio (PTH). O estímulo prolongado pode levar à autonomia na função paratireóidea. Inicialmente, o tratamento é clínico, mas a paratireoidectomia (PTx) pode ser necessária. A PTx pode ser total, subtotal e total seguida de autoimplante de tecido paratireóideo. Este trabalho compara as indicações e resultados dessas técnicas na literatura. Foi realizada revisão sistematizada dos trabalhos publicados entre janeiro de 2008 e março de 2014 sobre tratamento cirúrgico do hiperparatireoidismo secundário nas bases de dados MedLine e LILACS. Foram utilizados os termos: hiperparatireoidismo; hiperparatireoidismo secundário; glândulas paratireoides e paratireoidectomia. Foram restritos a pesquisas apenas em humanos; artigos disponíveis em meio eletrônico; publicados em português, espanhol, inglês ou francês. A amostra final foi constituída de 49 artigos. A PTx subtotal e a total mais autoimplante foram as técnicas mais utilizadas, sem consenso sobre a técnica mais efetiva. Embora haja certa preferência pela última, a escolha depende da experiência do cirurgião. Há consenso sobre a necessidade de identificar todas as paratireoides e sobre a criopreservação de tecido paratireóideo, quando possível, para enxerto em caso de hipoparatireoidismo. Exames de imagem podem ser úteis, especialmente nas recidivas. Tratamentos alternativos do HPT secundário, tanto intervencionistas quanto conservadores, carecem de estudos mais aprofundados.

Secondary hyperparathyroidism (HPT) has a high prevalence in renal patients. Secondary HPT results from disturbances in mineral homeostasis, particularly calcium, which stimulates the parathyroid glands, increasing the secretion of parathyroid hormone (PTH). Prolonged stimulation can lead to autonomy in parathyroid function. Initial treatment is clinical, but parathyroidectomy (PTx) may be required. PTx can be subtotal or total followed or not followed by parathyroid tissue autograft. We compared the indications and results of these strategies as shown in the literature through a systematic literature review on surgical treatment of secondary HPT presented in MedLine and LILACS from January 2008 to March 2014. The search terms were: hyperparathyroidism; secondary hyperparathyroidism; parathyroidectomy and parathyroid glands, restricted to research only in humans, articles available in electronic media, published in Portuguese, Spanish, English or French. We selected 49 articles. Subtotal and total PTx followed by parathyroid tissue autograft were the most used techniques, without consensus on the most effective surgical procedure, although there was a preference for the latter. The choice depends on surgeon’s experience. There was consensus on the need to identify all parathyroid glands and cryopreservation of parathyroid tissue whenever possible to graft if hypoparathyroidism arise. Imaging studies may be useful, especially in recurrences. Alternative treatments of secondary HPT, both interventional and conservative, require further study.

Localizacao de glandulas paratireoides ectopicas e supranumerarias em pacientes com hiperparatireoidismo secundario e terciario: descricao cirurgica e correlacao com ultrassonografia e cintilografia Tc99m-Sestamibi pre-operatorios / Localization of ectopic and supernumerary parathyroid glands in patients with secondary and tertiary hyperparathyroidism: surgical description and correlation with preoperative ultrasonography and Tc99m-Sestamibi scintigraphy

Introdução: O hiperparatireoidismo é uma consequência metabólica esperada na doença renal crônica (DRC). Paratireoides (PT) ectópicas e/ou supranumerárias podem ser causa de falha cirúrgica nos pacientes submetidos à paratireoidectomia total (PTX). Objetivo: Definir cirurgicamente a localização das PT, em pacientes com hiperparatireoidismo associado à DRC, e correlacionar esses achados com os exames pré-operatórios. Materiais e métodos: Foi conduzido um estudo retrospectivo com 166 pacientes submetidos à PTX. A localização das PT no intraoperatório foi registrada, sendo classificada como tópica ou ectópica. A localização pré-operatória, definida pela ultrassonografia (USG) e pela cintilografia Tc99m-Sestamibi (MIBI), foi comparada com aos achados cirúrgicos. Resultados: Nos 166 pacientes, foram identificadas 664 PT. Foram classificadas como tópicas e ectópicas 577 (86,4%) e 91(13,6%) glândulas, respectivamente. Oito PT supranumerárias foram encontradas (7 tópicas e 1 ectópica). As localizações mais comuns de PT ectópicas foram as regiões retroesofágica e tímica. Associadas, a USG e a MIBI não identificaram 56 glândulas (61,5%) ectópicas. Entretanto, a MIBI foi positiva para 69,7% daquelas localizadas nas regiões tímicas e mediastinal. Conclusão: A presença de glândulas ectópicas e supranumerárias em pacientes com hiperparatireoidismo associado à DRC é significativa. Os exames de imagem pré-operatórios não localizaram a maioria das glândulas ectópicas. A MIBI pode ter importância na identificação de PT nas regiões tímica e mediastinal. .

Introduction: Hyperparathyroidism is an expected metabolic consequence of chronic kidney disease (CKD). Ectopic and/or supernumerary parathyroid glands (PT) may be the cause of surgical failure in patients undergoing total parathyroidectomy (PTX). Aim: To define the locations of ectopic and supernumerary PT in patients with renal hyperparathyroidism and to correlate intraoperative findings with preoperative tests. Materials and methods: A retrospective study was conducted with 166 patients submitted to PTX. The location of PT during surgery was recorded and classified as eutopic or ectopic. The preoperative localizations of PT found by ultrasonography (USG) and Tc99m-Sestamibi scintigraphy (MIBI) were subsequently compared with intraoperative findings. Results: In the 166 patients studied, 664 PT were found. Five-hundred-seventy-seven (86.4%) glands were classified as eutopic and 91(13.6%) as ectopic. Eight supernumerary PT were found. The most common sites of ectopic PT were in the retroesophageal and thymic regions. Taken together, USG and MIBI did not identify 56 (61.5%) ectopic glands. MIBI was positive for 69,7% of all ectopic glands located in the mediastinal and thymic regions. Conclusion: The presence of ectopic and supernumerary PT in patients with renal hyperparathyroidism is significant. Although preoperative imaging tests did not locate most of ectopic glands, MIBI may be important for identifying ectopic PT in the mediastinal and thymic regions. .

Tumores marrons múltiplos em paciente com carcinoma de paratireoide / Multiple brown tumors in patient with parathyroid carcinoma

Os tumores marrons são complicações que entram no amplo espectro clínico de manifestações do hiperparatireoidismo, geralmente surgindo como lesões líticas, únicas, frequentemente associadas, na forma primária, ao adenoma de paratireoide (principal causa) e, na forma secundária, à insuficiência renal crônica. Porém, há relatos de apresentação múltipla. No presente artigo descreve-se um caso incomum de tumor marrom associado à carcinoma de paratireoide, apresentando outra peculiaridade rara, que é a manifestação como lesões múltiplas...

Brown tumors are complications that can be included in the wide clinical spectrum of hyperparathyroidism manifestations, usually emerging as lithic, single lesions that are frequently associated, in the primary form, with parathyroid adenoma (main cause) and, in the secondary form, with chronic kidney insufficiency. There are, however, reports of multiple manifestations. This paper describes an unusual case of brown tumor associated with parathyroid carcinoma, and also reports on the rare manifestation of the tumor with multiple lesions...

Supernumerary parathyroid glands in hyperparathyroidism associated with multiple endocrine neoplasia type 1 / Paratireoides supranumerárias em hiperparatireoidismo primário associado a neoplasia endócrina múltipla tipo 1

OBJECTIVE: To evaluate frequency, anatomic presentation, and quantities of supernumerary parathyroids glands in patients with primary hyperparathyroidism (HPT1) associated with multiple endocrine neoplasia type 1 (MEN1), as well as the importance of thymectomy, and the benefits of localizing examinations for those glands. METHODS: Forty-one patients with hyperparathyroidism associated with MEN1 who underwent parathyroidectomy between 1997 and 2007 were retrospectively studied. The location and number of supernumerary parathyroids were reviewed, as well as whether cervical ultrasound and parathyroid SESTAMIBI scan (MIBI) were useful diagnostic tools. RESULTS: In five patients (12.2%) a supernumerary gland was identified. In three of these cases (40%), the glands were near the thyroid gland and were found during the procedure. None of the imaging examinations were able to detect supernumerary parathyroids. In one case, only the pathologic examination could find a microscopic fifth gland in the thymus. In the last case, the supernumerary gland was resected through a sternotomy after a recurrence of hyperparathyroidism, ten years after the initial four-gland parathyroidectomy without thymectomy. MIBI was capable of detecting this gland, but only in the recurrent setting. Cervical ultrasound did not detect any supernumerary glands. CONCLUSION: The frequency of supernumerary parathyroid gland in the HPT1/MEN1 patients studied (12.2%) was significant. Surgeons should be aware of the need to search for supernumerary glands during neck exploration, besides the thymus. Imaging examinations were not useful in the pre-surgical location of these glands, and one case presented a recurrence of hyperparathyroidism.

OBJETIVO: Avaliação da frequência, da localização anatômica e do número de paratireoides extranumerárias em pacientes com hiperparatireoidismo primário (HPT1) associado a neoplasia endócrina múltipla tipo 1(NEM1), além da avaliação da importância da timectomia e da utilidade dos exames radiológicos para localização destes. MÉTODOS: Foram avaliados de forma retrospectiva 41 pacientes portadores de NEM1 com HPT1 submetidos a paratireoidectomia entre 1997 e 2007. O número de glândulas supranumerárias encontradas e a sua localização foram revisados, assim como a utilidade do ultrassom cervical e do SESTAMIBI (MIBI) de paratireoide como ferramentas diagnósticas. RESULTADOS: Em cinco pacientes (12,2%) foram identificadas glândulas supranumerárias. Em três destes (40%), as glândulas estavam próximas à glândula tireoide e foram encontradas durante a exploração cirúrgica. Os exames de imagem não foram úteis para a localização destas glândulas. Em um caso, apenas o exame anatomopatológico foi capaz de encontrar uma glândula extranumerária microscópica localizada no timo. No último caso, uma quinta glândula foi ressecada por meio de esternotomia após a recidiva do hiperparatireoidismo, cerca de 10 anos após a paratireoidectomia realizada sem timectomia na ocasião. Neste caso o MIBI detectou esta paratireoide apenas após a recidiva da doença. Em nenhum dos casos o ultrassom cervical foi capaz de detectar glândulas extranumerárias. CONCLUSÃO: A frequência de paratireoides supranumerárias em nossa casuística foi significativa (12,2%). Durante a exploração cervical, o cirurgião deve estar atento para localizar glândulas extranumerárias além do timo. Exames de imagem não foram úteis na localização préoperatória dessas glândulas, e em um caso houve recidiva do hiperparatireoidismo.

Fatores de risco de paratireoidectomia acidental em tireoidectomia / Risk factors for incidental parathyroidectomy during thyroidectomy

A paratireoidectomia acidental é um acontecimento frequente nas tireoidectomias. A literatura demonstra um achado de glândulas paratireoides, variando entre 6,4 por cento a 31 por cento em espécimes de exame anatomopatológico de glândula tireoide. OBJETIVO: Avaliar a quantidade de glândulas paratireoides encontradas em espécimes cirúrgicos de tireoidectomia e correlacionar com as variáveis demográficas e histopatológicas. MÉTODOS: Trabalho retrospectivo baseado nos laudos anatomopatológicos de tireoidectomias realizadas entre janeiro de 2007 a dezembro de 2008. RESULTADOS: O total de pacientes tireoidectomizados foi de 442, sendo o achado de glândulas paratireoides de 2,93 por cento, o que corresponde a 13 deste total. A presença de carcinoma papilífero de tireoide associado à paratireoidectomia acidental foi de 10,11 por cento contra a presença de patologia benigna de 1,4 por cento. CONCLUSÃO: O carcinoma papilífero de tireoide foi a variável associada ao maior número de paratireoidectomias acidentais.

Incidental parathyroidectomy is a common event in thyroid surgery. The literature shows a finding of parathyroid glands ranging from 6.4 percent to 31 percent in pathological specimens of the thyroid gland. OBJECTIVE: To collect the amount of parathyroid glands found in surgical specimens of thyroidectomy and correlate with the histopathological and demographic variables. METHODS: Retrospective study based on pathological reports of thyroidectomy from January 2007 to December 2008. RESULTS: 442 patients were submitted to total thyroidectomy, and 2.93 percent had parathyroid glands, which corresponded to 13 of this total. The presence of papillary thyroid carcinoma associated with incidental parathyroidectomy was 10.11 percent, compared to the benign lesion: 1.4 percent. CONCLUSION: Papillary thyroid carcinoma was the variable associated with increased number of incidental parathyroidectomy.

Total parathyroidectomy in a large cohort of cases with hyperparathyroidism associated with multiple endocrine neoplasia type 1: experience from a single academic center

Most cases of sporadic primary hyperparathyroidism present disturbances in a single parathyroid gland and the surgery of choice is adenomectomy. Conversely, hyperparathyroidism associated with multiple endocrine neoplasia type 1 (hyperparathyroidism/multiple endocrine neoplasia type 1) is an asynchronic, asymmetrical multiglandular disease and it is surgically approached by either subtotal parathyroidectomy or total parathyroidectomy followed by parathyroid auto-implant to the forearm. In skilful hands, the efficacy of both approaches is similar and both should be complemented by prophylactic thymectomy. In a single academic center, 83 cases of hyperparathyroidism/ multiple endocrine neoplasia type 1 were operated on from 1987 to 2010 and our first surgical choice was total parathyroidectomy followed by parathyroid auto-implant to the non-dominant forearm and, since 1997, associated transcervical thymectomy to prevent thymic carcinoid. Overall, 40% of patients were given calcium replacement (mean intake 1.6 g/day) during the first months after surgery, and this fell to 28% in patients with longer follow-up. These findings indicate that several months may be needed in order to achieve a proper secretion by the parathyroid auto-implant. Hyperparathyroidism recurrence was observed in up to 15% of cases several years after the initial surgery. Thus, long-term follow-up is recommended for such cases. We conclude that, despite a tendency to subtotal parathyroidectomy worldwide, total parathyroidectomy followed by parathyroid auto-implant is a valid surgical option to treat hyperparathyroidism/multiple endocrine neoplasia type 1. Larger comparative systematic studies are needed to define the best surgical approach to hyperparathyroidism/multiple endocrine neoplasia type 1.

Contact endoscopy for identifying the parathyroid glands during thyroidectomy.

Aim of this study was to analyse contact endoscopy as an auxiliary method for identifying parathyroid glands during thyroid surgery and to identify other variables that may interfere with this correlation. Overall, 125 patients underwent thyroid surgery between January 2004 and February 2006. The variables analysed were: the total duration of surgery; time taken to locate and identify parathyroid glands; improvement in identifying these; numbers of parathyroid glands located by the surgeon and confirmed by contact endoscopy; histopathological diagnosis; presence of thyroiditis; thyroid weight; number of parathyroid glands left in thyroid specimens; and number of parathyroid gland autotransplantations. A total of 331 parathyroid glands were observed by the surgeon. However, 282 glands were identified by contact endoscopy. Nine parathyroid glands (7.2%) were observed together with thyroid specimens (Kappa = 0.534). The longer the total duration of surgery (p = 0.03) and time taken to locate and identify (p = 0.00) the parathyroid glands by contact endoscopy, the lower the observed agreement. The second year of performing contact endoscopy led to better agreement between the results (p = 0.02). In conclusion, contact endoscopy is an efficient auxiliary method for identifying parathyroid glands during thyroid surgery. During the period studied, association between total duration of surgery and time taken to locate and identify parathyroid glands was statistically significant.

Estudo prospectivo da hipocalcemia clínica e laboratorial após cirurgia da tireoide / Prospective study of clinical and laboratorial hypocalcemia after thyroid surgery

A hipocalcemia pode ser detectada clínica e laboratorialmente após a tireoidectomia. Objetivo: Analisar a incidência e fatores de risco da hipocalcemia clínica e laboratorial após cirurgia da glândula tireoide. Métodos: Trata-se de um estudo prospectivo de 91 pacientes submetidos à tireoidectomia. Aspectos demográficos, intraoperatórios e anatomopatológicos foram correlacionados com os achados de hipocalcemia. Rresultados: Foram considerados fatores de risco para o hipoparatireoidismo clínico a faixa etária acima dos 50 anos (p = 0,022) e realização de cirurgia não parcial (p < 0,001). Foi considerado fator de risco para o hipoparatireoidismo laboratorial a 48 horas a cirurgia não parcial (p = 0,004). Não houve fator de risco para o surgimento do hipoparatireoidismo laboratorial a um mês. Houve significância entre hipotireoidismo laboratorial a 48 horas e a um mês. Conclusões: A extensão da tireoidectomia é fator de risco para o hipoparatireoidismo clínico e laboratorial, enquanto a faixa etária é fator para o hipoparatireoidismo clínico. A detecção de hipoparatireoidismo laboratorial com 48 horas de pós-operatório é fator predisponente para o hipoparatireoidismo laboratorial com um mês de pós-operatório, mas caracterizou-se o caráter temporário da maior parte dos casos.

Hypocalcemia can be detected clinically and through lab tests after thyroidectomy. AIM: To analyze the incidence and risk factors of clinical and laboratorial hypocalcemia after thyroid surgery. Methods: Prospective study of 91 patients undergoing thyroidectomy. Demographics, intraoperative, and pathological aspects were correlated to our hypocalcemia findings. Results: Age higher than 50 (p = 0.022) and complete thyroidectomy (p < 0.001) were considered risk factors for hypoparathyroidism. Complete thyroidectomy was considered a risk factor for the 48-hour laboratorial hypoparathyroidism (p = 0.004). There was no risk factor associated with the one-month laboratorial hypoparathyroidism. There was significance between the 48-hour and the one-month laboratorial hypoparathyroidism. Conclusions: Thyroidectomy extension is a risk factor for both the clinical and laboratorial hypoparathyroidism, whereas age is a risk factor for clinical hypoparathyroidism. The detection of 48-hour laboratorial hypoparathyroidism is a predisposing factor for the one-month laboratorial hypoparathyroidism. However, most of the cases were temporary.