[Post-tonsillectomy hyponatremia: a posible lethal complication]. / Hiponatremia post-adenotonsilectomía en niños: una posible complicación letal.

Death following tonsillectomy in children is very rare. It is most commonly due to bleeding or aspiration. But, there is another potentially lethal complication following the pediatric tonsillectomy, post-surgical hyponatremia. Acute hyponatremia can lead to catastrophic neurological sequelae. Although this cmplication is not related to the surgical technique, it is potentially life-threatening. The most important factor for hospital acquired hyponatremia is the administration of excessive amounts of hypotonic fluid in situations in wich antidiuretic hormone (ADH) is secreted for non osmotic reasons. We will discuss the etiology and pathophysiology of post-operative hyponatremia. We expect that fatal post-operative hyponatremia can be avoided in pediatric tonsillectomy patients.

[Primary nasal tuberculosis: a forgotten disease?]. / Tuberculosis nasal primaria: una patología olvidada?

Nasal tuberculosis represents a rare manifestation of infection by Mycobacterium tuberculosis. Clinically, it appeared to resemble cancer presenting as a nasopharyngeal mass with concomitant enlarged lymph nodes. It is important to consider tuberculosis in the differential diagnosis of all nasopharyngeal lesions and take biopsy samples for histological and bacteriological studies. Antituberculosis treatment is satisfactory with standard anti-tuberculous chemotherapy. Although this is a rare finding, it should be considered when a patient presents with nasal obstruction.

[Riedel's thyroiditis: a report of a case with fatal outcome]. / Tiroiditis de Riedel: a propósito de un caso de evolución letal.

The Riedel's thyroiditis is a chronic inflammatory disease of the thyroid gland characterized by a process of fibrosis that destroys the gland partially, extending to the adjacent cervical structures. Its origin is unknown, although there are several theories in this respect. The clinical manifestations are not specific and it confuses frequently with neoplasia or infection, like a hard and painless thyroid mass that causes compressive symptoms. In this work, we report a case with lethal outcome.

[Rosai-Dorfman disease (sinus histiocytosis with multiple lymphadenopathy]. / Enfermedad de Rosai-Dorfman (histiocitosis sinusal con linfadenopatías masivas): a propósito de un caso.

The entity known as sinus histiocytosis with massive lymphadenopathy (SHML), or Rosai-Dorfman disease, is an uncommon benign proliferation of hematopoietic and fibrous tissue is that often present in the head and neck region. Its initial manifestations include bilateral cervical adenopathies, and in a high percentage it has an extranodal affectation. Its cause is unknown and it usually resolves satisfactorily. We present a case and we revise the literature.

[Monostotic fibrous dysplasia of the frontal sinus with orbital extension]. / Displasia fibrosa monostótica de seno frontal con extensión orbitaria.

We present the case of a localized monostotic fibrous dysplasia in the frontal sinus with orbital extension and persistency after the first surgery; it had to be operated again with a fronto-orbitary reconstruction. The fibrous dysplasia is a rare bony alteration with transformation of the healthy bony tissue for a disestructuredone. Its etiology is unknown and can be associated to different syndromes, such as Albright's Disease. Its treatment is surgical, but presents a high percentage of recurrence, this is the xenson why it needs a close follow up.

[Asymptomatic bilateral cystic lesion in the petrous apex: differential diagnosis]. / Lesión quística bilateral asintomática en la punta del peñasco: diagnóstico diferencial.

We report in this work the casual find of two bilateral and symmetrical cystic images on the apex petrosus, asymptomatic and with periodic controls. In the review of the literature we haven't found another case of this entity. The differential diagnosis of this pathology is showed. We expose the most characteristic imagings.

Osteosarcoma de senos paranasales y base de cráneo / Paranasal sinuses and cranial base osteosarcoma

Los osteosarcomas son tumores osteoides malignos poco frecuentes en cabeza y cuello. Suelen aparecer a nivel maxilar y mandibular, con escasa tendencia a la metástasis a distancia pero con gran recurrencia local. En este trabajo presentamos un caso en una localización más infrecuente, la región etmoido-orbital y base de cráneo; se trata de un osteosarcoma de gran tamaño, bien diferenciado con áreas que semejan la displasia fibrosa.Presentamos el caso clínico y revisamos la literatura (AU)

[Sinonasal hemangiopericytoma]. / Hemangiopericitoma nasosinusal.

The hemangiopericytoma is an infrequent vascular tumour in the nose, that produces epistaxis and obstructive respiratory clinical like principal symptoms. It has, in the nose, special clinical characteristics that makes it different of the others localitations. We report a case of nasosinusal hemangiopericytoma with appearance of polyposis and treated with nasosinusal endoscopic surgery; after that, the patient had a complete remission and subsequent follow-up without recurrence. We review the literature and study the most important characteristics.