Tumores Neuroendocrinos: un desafío transversal / Update on neuroendocrine tumors

Neuroendocrine Tumors (NETs) encompass a wide variety of tumors arising from neuroendocrine cells, which produce bioactive substances. The incidence of NETs increased significantly lately, becoming one of the most common tumors of the digestive tract. Their clinical presentation is as diverse as their capacity for hormone production. Carcinoid syndrome is the most common hormonal syndrome produced by NETs and is characterized by diarrhea, flushing and cardiac valvular lesions. New research brought multiple changes in the classification of these neoplasms and a new understanding about their diagnosis and treatment, promoting a multidisciplinary approach. Somatostatin analogues, radiation, biological, and cytotoxic drugs have improved the prognosis of these patients, which entails a great challenge for healthcare providers.

Evaluación de la recolección de orina de 24 horas a partir de la creatininuria: fórmulas para estimarla y su rendimiento / Performance of formulas for the evaluation of 24-hour urine collections using urine creatinine excretion

Creatinine excretion is widely used as a method to evaluate the adequacy of urine collection in different clinical settings. Many factors influence its elimination, such as protein intake, exercise, muscle mass, age, and sex, among many others. As 24-hour urine collections can be cumbersome, several equations have been developed to aid clinicians to correctly interpret results derived from them. In this review article, we report the factors that can modify creatinine excretion and we evaluate the accuracy of different published equations to estimate 24-hour urine creatinine excretion.

Hipofosfatemia inducida por drogas: fierro carboximaltosa e imatinib. Casos clínicos / Hypophosphatemia induced by carboxymaltose iron and imatinib. Report of two cases

Hypophosphatemia is a relatively frequent and a potentially serious adverse drug effect. Clinically it is characterized by bone pain and muscle weakness. There are several mechanisms by which a drug can induce hypophosphatemia and they can be classified according to whether or not they are mediated by an excess of Fibroblast Growth Factor 23 (FGF23). We report two patients with the condition: (i) A 49-year-old woman with Chronic Myeloid Leukemia (CML) and gastric sleeve surgery at 46 years of age. After receiving intravenous carboxymaltose iron in one occasion due to refractory anemia, she developed symptomatic hypophosphatemia. Urinary phosphate losses associated with high FGF23 levels were confirmed. Plasma phosphate returned to normal values 90 days after the iron administration. (ii) A 40-year-old man with a history of CML in whom imatinib was started. He developed symptomatic hypophosphatemia due to non FGF23-mediated hyperphosphaturia. As treatment with imatinib could not be interrupted, hypophosphatemia and its symptoms resolved with oral phosphate intake. These cases illustrate the importance of recognizing and treating drug-induced hypophosphatemia in a timely manner, and thus avoid the morbidity associated with this entity.

Hipofisitis linfoplasmocitaria y fibrosis retroperitoneal asociadas a un síndrome poliglandular autoinmune: enfermedades relacionadas con IgG4. Caso clínico / Hypophysitis and retroperitoneal fibrosis associated with autoimmune polyglandular syndrome and IgG4-related disease: report of one case

We report a 23 year old woman presenting with a nephrotic syndrome due to minimal change disease, central diabetes insipidus, primary hypothyroidism, vitiligo and universal alopecia. Eleven years later, she presented secondary amenorrhea due to hypogonadotropic hypogonadism, with mild hyperprolactinemia and central adrenal insufficiency. A magnetic resonance imaging of the sella turcica showed a pituitary mass with suprasellar extension that was resected using a transsphenoidal approach. Pathology confirmed the presence of a lymphoplasmacytic hypophysitis. She needed a second surgical resection due to mass growth and neuro-ophthalmologic impairment. One year later, systemic lupus erythematosus, arterial hypertension and type 2 diabetes mellitus were diagnosed. Two years later, due to back pain, constipation and renal failure, retroperitoneal fibrosis was found, satisfactorily treated with glucocorticoids and colchicine. Hence, this clinical vignette shows the coexistence of autoimmune polyglandular syndrome with retroperitoneal fibrosis and lymphoplasmacytic hypophysitis. Tissue analysis showed the presence of IgG4 producing plasma cells in the pituitary and retroperitoneum, which constitute a basis for the diagnosis of IgG4 related disease.

Clomiphene citrate treatment for late onset hypogonadism: rise and fall

ABSTRACT Objective: Previous series have demonstrated that Clomiphene Citrate (CC) is an effective treatment to increase Total Testosterone (TT) in Late Onset Hypogonadism (LOH) patients. However, what happens to TT levels after ending CC treatment is still debatable. The objective of this study is to evaluate TT levels 3 months after the discontinuation of CC in patients with LOH who were previously successfully treated with the same drug. Materials and Methods: Twenty-seven patients with LOH that were successfully treated (achieved TT levels >11nmol/l) with CC 50mgs daily for 50 days were prospectively recruited in our Andrological outpatient clinic. CC was then stopped for 3 months and TT levels were measured at the end of this period. Results: Mean TT level before discontinuation of CC was 22.7±8.1nmol/L (mean±SD). Three months after discontinuation, mean TT level significantly decreased in all patients, 10.2±3.9nmol/l (p<0.01). Twenty-one patients (78%) decreased TT levels under 11nmol/L. Six patients (22%) had TT levels that remained within the normal recommended range (≥11nmol/l). No statistical significant differences were observed between both groups. Conclusion: In the short term LOH does not seem to be a reversible condition in most patients after CC treatment. More studies with longer follow-up are needed to evaluate the kinetics of TT in LOH.

Vasculitis de grandes vasos en paciente con vasculitis ANCA (+): Caso clínico / Large vessel involvement in ANCA-associated vasculitis: Report of one case

Pauci-immune glomerulonephritis in systemic vasculitides usually have anti-neuthrophil cytoplasmic antibodies (ANCA). However, vasculitides of large vessels such as Takayasu’s and giant cell (temporal) arteritis do not. Exceptionally ANCA(+) small vessel vasculitides are associated with large vessel vasculitis. It may be a coincidence or both vasculitides have a common pathogenesis. We report a 30 years old woman on hemodialysis due to a chronic glomerulonephritis ANCA(+) diagnosed nine years ago. Eight years later, she presented with an aortitis with severe stenosis of distal aorta and vasculitis of left subclavian artery. She was treated with adrenal steroids and cyclophosphamide. During the ensuing five years she has been stable and without signs of reactivation of the disease.