Management of hypopituitarism: a perspective from the Brazilian Society of Endocrinology and Metabolism

ABSTRACT Hypopituitarism is a disorder characterized by insufficient secretion of one or more pituitary hormones. New etiologies of hypopituitarism have been recently described, including head trauma, cerebral hemorrhage, and drug-induced hypophysitis. The investigation of patients with these new disorders, in addition to advances in diagnosis and treatment of hypopituitarism, has increased the prevalence of this condition. Pituitary hormone deficiencies can induce significant clinical changes with consequent increased morbidity and mortality rates, while hormone replacement based on current guidelines protects these patients. In this review, we will first discuss the different etiologies of hypopituitarism and then address one by one the clinical aspects, diagnostic evaluation, and therapeutic options for deficiencies of TSH, ACTH, gonadotropin, and GH. Finally, we will detail the hormonal interactions that occur during replacement of pituitary hormones.

Prolonged Neonatal Jaundice with Deranged Thyroid Function Test

@#Congenital central hypothyroidism (CCH) is a rare disorder that results from deficient biosynthesis of thyroid hormone due to defective thyroid gland stimulation by thyroid stimulating hormone (TSH). Diagnosis is typically established biochemically by low free thyroxine (fT4) and inappropriately low or normal TSH levels after excluding all other causes of discordant thyroid function test (TFT). Here, we report a case of a baby girl who presented with prolonged jaundice at day 15 of life with normal cord blood TSH performed as routine screening for congenital hypothyroidism. Serial TFT revealed declining serum fT4 with normal TSH consistent with CCH. Her jaundice resolved prior to levothyroxine replacement. CCH is commonly missed on cord blood TSH-based newborn screening leading to a delay in diagnosis, potentially resulting in neurodevelopmental delay. Hence, although CCH has a lower incidence than congenital primary hypothyroidism, a high index of suspicion is essential for timely diagnosis.

Dynamic changes of central thyroid functions in the management of Cushing's syndrome

ABSTRACT Objective The aim of this study was to determine the frequency of central thyroid dysfunctions in Cushing's syndrome (CS). We also aimed to evaluate the frequency of hyperthyroidism due to the syndrome of the inappropriate secretion of TSH (SITSH), which was recently defined in patients with insufficient hydrocortisone replacement after surgery. Materials and methods We evaluated thyroid functions (TSH and free thyroxine [fT4]) at the time of diagnosis, during the hypothalamo-pituitary-adrenal axis recovery, and after surgery in 35 patients with CS. The patients were separated into two groups: ACTH-dependent CS (group 1, n = 20) and ACTH-independent CS (group 2, n = 15). Patients' clinical and laboratory findings were evaluated in five visits in the outpatient clinic of the endocrinology department. Results The frequency of baseline suppressed TSH levels and central hypothyroidism were determined to be 37% (n = 13) and 26% (n = 9), respectively. A negative correlation was found between baseline cortisol and TSH levels (r = -0.45, p = 0.006). All patients with central hypothyroidism and suppressed TSH levels showed recovery at the first visit without levothyroxine treatment. SITSH was not detected in any of the patients during the postoperative period. No correlation was found between prednisolone replacement after surgery and TSH or fT4 levels on each visit. Conclusion Suppressed TSH levels and central hypothyroidism may be detected in CS, independent of etiology. SITSH was not detected in the early postoperative period due to our adequate prednisolone replacement doses.

A rare association of central hypothyroidism and adrenal insufficiency in a boy with Williams-Beuren syndrome

Primary hypothyroidism related to morphological and volumetric abnormalities of the thyroid gland is one of the commonest of several endocrine dysfunctions in Williams-Beuren syndrome (WBS). We report a 10-month-old boy with WBS who presented with central hypothyroidism. During the neonatal period, he had prolonged jaundice, feeding difficulties and episodes of colic that continued during early infancy. Additionally, there was slowing of growth and mild developmental delay. He underwent surgical repair for supravalvular aortic stenosis at 6 months of age. An evaluation done to exclude cortisol deficiency before initiating levothyroxine lead to the detection of secondary adrenal insufficiency, unreported previously in WBS. In addition, insulin-like growth factor-1 (IGF-1) and IGF-binding protein-3 levels were low. This report of hypopituitarism in WBS indicates a need for complete evaluation of pituitary dysfunction in children with WBS.

Histiocytosis: An Uncommon Presentation with Hypopituitarism.

Langerhans cell histiocytosis is a multi system disorder with a certain predilection for involving hypothalamic pituitary axis. We hereby report a 7 year old girl presenting with polyuria, polydipsia and growth retardation. The girl had a past history of pain in right hip joint and nodular region over chest. Water deprivation test confirmed the diagnosis of central diabetes inspidus. Other investigations revealed Growth hormone deficiency and central hypothyroidism. X-ray and MRI hip revealed absent right inferior pubic ramus with bone marrow biopsy confirming the diagnosis of histiocytosis. Patient was treated with nasal Arginine Vasopressin spray, subcutaneous growth hormone and oral thyroxine.

Delayed Recognition of Central Hypothyroidism in a Neonate Born to Thyrotoxic Mother.

We describe a neonate born to a mother with uncontrolled thyrotoxicosis, who was euthyroid during first week of life and later developed central hypothyroidism.

Hipotiroidismo central en pacientes con el síndrome de Prader-Willi durante los 2 primeros años de vida / Central hypothyroidism in patients with Prader-Willi syndrome during the first 2 years of life

Introducción. El síndrome de Prader-Willi SPW) es un trastorno genético causado por la pérdida de expresión de genes de origen paterno en la región cromosómica compleja 15q11-q13. El fenotipo clínico ha sido bien caracterizado, especialmente relacionado con la disfunción hipotalámica. Aunque entre 20 a 30% de los pacientes con SPW tienen hipotiroidismo central (HC), no ha sido bien definida la función tiroidea durante los dos primeros años de vida. Objetivo: evaluar la función hipotalámica-pituitaria-tiroidea en lactantes con SPW. Diseño del estudio: 18 pacientes con SPW entre 0,16 y 2 años de edad fueron incluídos en un estudio prospectivo. El diagnóstico de SPW se basó en los hallazgos clínicos y en el análisis molecular. Se calcularon los escores de desviacion estándar (SDS) de la T4 total (T), T4 libre (L), T3 y TSH en suero en todos los pacientes incluídos en el estudio. Resultados: En 14 de los 18 pacientes con SPW, se encontraron niveles de T4T y/o T4L menores a -2 SDS (44,4 y 55,5%, respectivamente), mientras que solamente en 1 paciente con SPW el nivel de T3 estaba por debajo de -2 SDS. Conclusión: Este estudio muestra que la incidencia de HC es alta en lactantes con SPW. Los pediatras deben tener en cuenta el diagnostico de HC en este período crítico de la acción de la hormona tiroidea en el desarrollo neurológico (AU)

Introduction. Prader-Willi syndrome (PWS) is a genetic disorder caused by the loss of expression of paternally transcribed genes in a highly imprinted region of chromosome 15q11- q13. The clinical phenotype has been well characterized, mostly related to hypothalamic dysfunction. Even though central hypothyroidism (CH) has been documented in 20 to 30% of PWS patients, thyroid function has not been well characterized during the first 2 years of life. Objective: to evaluate hypothalamic-pituitary-thyroid function in infant PWS patients. Study design: Eighteen PWS patients, aged 0.16 to 2 years, were included in a prospective study. PWS diagnosis was based on clinical features and molecular analysis. Serum total (T) T4, free (F) T4, T3 and TSH standard deviation scores (SDS) were calculated in all PWS patients included in the study. Results: In 14 out of 18 PWS patients, serum TT4 and/or FT4 levels less than -2 SDS ( 44.4 and 55.5 %, respectively) were found, while in only 1 PWS patient serum T3 levels was below -2 SDS. Conclusion: This study shows that there is a high incidence of CH in infant PWS patients. Pediatricians should be aware of this diagnosis in this critical period of thyroid hormone action on neurological development (AU)