Estudios clínicos y genéticos en tres miembros de una familia afectados con adenomas hipofisarios aislados con prolactinomas homogéneos / Clinical and genetic studies of a three-member familial isolated pituitary adenoma with homogeneous prolactinomas

La mayoría de los adenomas hipofisarios son esporádicos, pero un 3-5% puede ocurrir en un contexto familiar y hereditario. Este es el caso de la neoplasia endocrina múltiple de tipo 1 (NEM1), complejo de Carney (CNC) y adenomas hipofisarios aislados familiares (FIPA). El FIPA es una condición infrecuente, que ocurre en un contexto familiar, no asociada a NEM t ipo1 ni CNC. Los FIPA pueden ser homogéneos (todos los adenomas tienen el mismo fenotipo) o heterogéneos (diferente fenotipo tumoral). Describimos una familia congolesa en la que dos hermanas y una prima fueron diagnosticadas a los 29, 32 y 40 años, respectivamente, con un prolactinoma (FIPA homogéneo). Las pacientes presentaron macroadenomas no invasivos al momento del diagnóstico, con buena respuesta biológica y tumoral al tratamiento con cabergolina hasta una dosis máxima de 1.5 mg/semanal. De las dos hermanas, una cursó un embarazo sin complicaciones. Durante el seguimiento de 12 años, ninguna de ellas presentó elementos clínicos o biológicos compatibles con NEM1 o CNC, por lo que dichos genes no se estudiaron. El análisis genético en dos de las pacientes permitió descartar la posibilidad de una mutación germinal del gen aryl hydrocarbon receptor interacting protein (AIP). Se considera que el 80% de los pacientes con FIPA no presentan mutación del gen AIP, por lo que se requieren futuros estudios en este tipo de familias, para poder determinar otros genes afectados involucrados en su fisiopatología.

Most pituitary adenomas are sporadic, but 3-5% can occur in a family and hereditary context. This is the case of multiple endocrine neoplasia type 1 (MEN1), Carney complex (CNC) and familial isolated pituitary adenomas (FIPA). FIPA is an infrequent condition that occurs in a family context, not associated with MEN type1 or CNC. FIPA kindred can be homogeneous (all adenomas affected in the family having the same tumor phenotype) or heterogeneous (different tumor phenotypes in the affected members). We describe a Congolese family in which two sisters and a cousin were diagnosed with a prolactinoma (homogenous FIPA) at the ages of 29, 32 and 40 years, respectively. The patients presented with macroadenomas at the time of diagnosis, non-invasive tumors and good biological response to cabergoline treatment (maximum dose of 1.5 mg/weekly). Of these two sisters, one went through a pregnancy without complications. Because no MEN1 and CNC clinical and biochemical features were detected during the 12-year follow-up, these genes were not investigated. The genetic analysis of the aryl hydrocarbon receptor interacting protein (AIP) was normal. As nearly 80% of patients with FIPA do not have a mutation in the AIP gene, future studies in these families are required to identify other affected genes involved in their physiopathology.

Conversion to Graves disease from Hashimoto thyroiditis: a study of 24 patients

ABSTRACT Objective: The conversion of Hashimoto's thyroiditis (HT) to hyperthyroidism due to thyrotropin receptor antibodies is intriguing and considered rare. The contribution of TSH receptor blocking antibodies (TRAb), which may be stimulators (TSAb) or blockers (TBAb), is suspected. We describe clinical and biological variables in a series of patients switching from Hashimoto's thyroiditis to Grave's disease. Subjects and methods: Retrospective case study of 24 patients with Hashimoto's thyroiditis followed during 48 ± 36 months that developed later Graves' disease (GD). These variables were analysed in the hypo and hyperthyroid phase: age, sex, initial TSH, free triiodothyronine (fT3), free thyroxine (fT4), anti-TPO, TBII antibodies, parietal cell autoantibodies, time between hypo and hyperthyroidism, thyroid volume and levothyroxine doses (LT). Results: In HT, mean TSH was 9.4 ± 26.1 UI/L and levothyroxine treatment was 66.2 ± 30.8 µg/day. The switch to GD was observed 38 ± 45 months after HT diagnosis. As expected, we found significant differences on TSH, FT3, FT4 and TBAb levels. Three out of 14 patients had parietal cell autoantibodies. In two of these three cases there was an Helicobacter pylori infection. There were no significant differences between HT and GD groups with respect to thyroid volume. Conclusions: To our knowledge, large series documenting the conversion of HT to GD are scarce. Although rare, this phenomenon should not be misdiagnosed. Suspicion should be raised whenever thyroxine posology must be tapered down during the follow-up of HT patients. Further immunological and genetic studies are needed to explain this unusual autoimmune change.

Use of cinacalcet and sunitinib to treat hypercalcaemia due to a pancreatic neuroendocrine tumor

SUMMARY Neuroendocrine tumors (NETs) can secrete hormones, including ectopic secretions, but they have been rarely associated with malignant hypercalcemia. A 52-year-old man with a history of diabetes mellitus was diagnosed with a pancreatic tumor. A pancreatic biopsy confirmed a well-differentiated pancreatic NET (pNET). The patient subsequently developed liver metastasis and hypercalcemia with high 1,25 OH vitamin D and suppressed parathyroid hormone (PTH) levels. Hypercalcemia was refractory to chemotherapy, intravenous saline fluids, diuretics, calcitonin and zoledronate. Cinacalcet administration (120 mg/day) resulted in a significant calcium reduction. Hypocalcemia was observed when sunitinib was added three months later and cinacalcet was stopped. Subsequently, the calcium and PTH levels normalized. After six months, we observed 20% shrinkage of the pancreatic tumor and necrosis of a liver metastasis. Cinacalcet is an allosteric activator of the calcium receptor agonist, and it is used for severe hypercalcemia in patients with primary (benign and malignant) hyperparathyroidism. In this patient, cinacalcet demonstrated a calcium lowering effect, normalized hypophosphatemia, and improved the clinical condition of the patient. The mechanism through which cinacalcet improved PTH-rp mediated hypercalcemia is still unclear, but studies have suggested that a potential mechanism is the activation of calcitonin secretion. Sunitinib is an oral multi-targeted tyrosine kinase inhibitor used to treat advanced pNETs. The hypocalcemic effects of sunitinib have not been previously described in a patient with pNET. Here, we report for the first time the successful combination of cinacalcet and sunitinib in the treatment of a pNET patient presenting with malignant hypercalcemia.

Asociación de craneofaringioma y síndrome de Klinefelter en la transición puberal: un desafío diagnóstico / Craniopharyngioma and Klinefelter syndrome during the pubertal transition: A diagnostic challenge

Los craneofaringiomas son de los tumores hipofisarios más frecuentes en la niñez y, sea por su evolución o por el tratamiento que requieren, pueden comprometer el desarrollo puberal. El síndrome de Klinefelter es la causa más frecuente de hipogonadismo hipergonadotrópico en el varón. La presentación concomitante de ambas entidades es extremadamente baja (1/10(9)) y plantea un interrogante acerca de una probable asociación fisiopatológica. Se presenta el caso de un paciente belga de 18 años, con diagnóstico de craneofaringioma en la niñez y panhipopituitarismo luego del tratamiento quirúrgico y radioterápico. Al llegar a los 14 años, se inició la inducción puberal con gonadotropinas. Ante la falta de respuesta clínica, se completó una evaluación genética, que evidenció, de manera homogénea, una trisomía XXY. La falta de respuesta al tratamiento de inducción con gonadotropina exógena reveló la asociación de hipogonadismo primario y secundario, que demostró la importancia del seguimiento multidisciplinario que estos pacientes requieren.

Craniopharyngioma is the most common pituitary tumor in childhood. It can compromise the pubertal development because of its evolution or treatment. Syndrome of Klinefelter is the most common cause of hipergonadotrophic hypogonadism in males. The concomitant presentation of both entities is extremely low (1/10(9)) and the pathophysiological association is questionned. We present the case of a 18-year-old Belgian patient. He had a diagnosis of craniopharyngioma in childhood and he presented with panhypopituitarism after radiotherapy and surgical treatment. At the age of 14, he started pubertal induction with gonadotropin therapy without clinical response. A genetic evaluation confirmed a homogeneous 47, XXY karyotype. Failure of exogenous gonadotropin therapy revealed the hidden association of primary and secondary hypogonadism, demonstrating the importance of the followup and a multidisciplinary approach in these patients.

El síndrome de Pasqualini: hipoandrogenismo con espermatogénesis conservada

Pasqualini y Bur publican el primer caso de eunucoidismo con espermatogénesis conservada en 1950 en la Revista de la Asociación Médica Argentina. El síndrome de hipoandrogenismo con espermatogénesis incluye: (a) eunucoidismo bien definido, (b) testículos de volumen normal con espermatogénesis completa, llegando a espermatozoides maduros en una elevada proporción de tubos seminíferos, con células de Leydig indiferenciadas e inmaduras, (c) compensación funcional completa mediante la administración de gonadotrofina coriónica, mientras ésta se aplique (d) gonadotrofinas urinarias totales dentro de límites normales, y (e) esta definición fue ampliada con la actividad normal de las otras hormonas adenohipofisarias y la ausencia de malformaciones congénitas en la mayoría de los casos. En la fisiopatogenia del síndrome de Pasqualini, conocido también como síndrome del "eunuco fértil", se demostró primero la ausencia de hormona luteinizante (LH) en el plasma y orina de estos pacientes. El segundo gran avance fueron los estudios funcionales y genéticos que validaron la hipótesis de un déficit funcional de LH en estos hombres, extendido luego a las mujeres. Varios grupos, incluyendo el nuestro, demostrarían en estos casos una LH con diferentes grados de actividad inmunológica pero biológicamente inactiva, a partir de una o más mutaciones invalidantes en el gen LHB. Por último, la comprensión acabada del síndrome de Pasqualini permitiría revertir el fenotipo y la infertilidad de estos pacientes a partir de la utilización de gonadotrofina coriónica y las modernas técnicas de fertilidad in vitro. Este artículo es una revisión histórica y un homenaje a la memoria de Rodolfo Q. Pasqualini.

Pasqualini and Bur published the first case of eunuchoidism with preserved spermatogenesis in 1950 in Revista de la Asociación Médica Argentina. The hypoandrogenism with spermatogenesis syndrome included: (a) eunuchoidism, (b) testis with normal spermatogenesis and full volume, with mature spermatozoa in a high proportion of seminiferous tubes and undifferentiated and immature Leydig cells (c) full functional compensation through the administration of chorionic gonadotropin hormone, while hCG is administered (d) total urinary gonadotrophins within normal limits (e) this definition supposes the normal activity of the pituitary and the absence of congenital malformations in general. A first step in the understanding of the physiopathogeny of Pasqualini syndrome or the so called "fertile eunuch" syndrome was the absence of LH in plasma and urine of patients. The second breakthrough was the functional and genetic studies that validated the hypothesis of a functional deficit of LH in these men: it will then also be described in some women. Different groups including ours demonstrated in these cases a LH with varying degrees of immunological activity but biologically inactive in most of the patients, due to one or more inactivating mutations in the LHB gene. Finally, the full comprehension of Pasqualini syndrome allowed to reverse the hypoandrogenic phenotype and to restore fertility in these patients through the use of chorionic gonadotropin and the modern in-vitro fertility techniques. This article is an historical review and a tribute to the memory of Rodolfo Q. Pasqualini.