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DISORDERS OF THE ANTERIOR PITUITARY AND
HYPOTHALAMUS
DR. JUAN CARLOS BECERRA MARTÍNEZ
CÁTEDRA DE MEDICINA INTERNA-MC3087
Tecnológico de MonterreyCampus Guadalajara
Anterior Pituitary Hormone Expression and Regulation
Harrison’s 18th Edition.
Harrison’s 18th Edition.
(GnRH) pulses induce secretory pulses of (LH).
Harrison’s 18th Edition.
Etiology of Hypopituitarism
Harrison’s 18th Edition.
Development/structural Pituitary dysplasia/aplasia Congenital CNS mass, encephalocele Primary empty sella
Congenital hypothalamic disorders (septo-optic dysplasia: dysgenesis of the corpus callosum)
Prader-Willi syndrome:○ Hypogonadotropic hypogonadism, hyperphagia-obesity, chronic muscle
hypotonia, mental retardation, and adult-onset diabetes mellitus Laurence-Moon-Biedl syndrome:
○ Mental retardation, renal abnormalities, obesity, and hexadactyly, brachydactyly, or syndactyly. GnRH deficiency occurs in 75%
Kallmann syndrome:○ Defective (GnRH) synthesis and is associated with anosmia or hyposmia
due to olfactory bulb agenesis.
Etiology of Hypopituitarism
Harrison’s 18th Edition.
Traumatic Surgical resection Radiation damage Head injuries
Etiology of Hypopituitarism
Harrison’s 18th Edition.
Neoplastic Pituitary adenoma Parasellar mass (germinoma, ependymoma, glioma) Rathke's cyst: pars intermedia benign cystsCraniopharyngioma Hypothalamic hamartoma, gangliocytoma Pituitary metastases (breast, lung, colon carcinoma) Lymphoma and leukemia Meningioma
Etiology of Hypopituitarism
Harrison’s 18th Edition.
Infiltrative/inflammatoryLymphocytic hypophysitis:
○ Postpartum ○ MRI resembles an adenoma○ Resolves after several months of glucocorticoid
treatmentHemochromatosis: hereditary, (liver, pancreatic, heart)SarcoidosisHistiocytosis X: clonal proliferation of Langerhans cells
Etiology of Hypopituitarism
Harrison’s 18th Edition.
Vascular Pituitary apoplexy Pregnancy-related (infarction with diabetes;
postpartum necrosis) Sickle cell disease Arteritis
Etiology of Hypopituitarism
Harrison’s 18th Edition.
Infections Fungal (histoplasmosis)Parasitic (toxoplasmosis) Tuberculosis Pneumocystis carinii
Etiology of Hypopituitarism
Harrison’s 18th Edition.
Trophic hormone failure associated with pituitary compression or destruction usually occurs sequentially: GH > FSH > LH > TSH > ACTH.
During childhood, growth retardation is often the presenting feature, and in adults, hypogonadism is the earliest symptom.
Tests of Pituitary Sufficiency
Harrison’s 18th Edition.
Tests of Pituitary Sufficiency
Harrison’s 18th Edition.
Tests of Pituitary Sufficiency
Harrison’s 18th Edition.
Treatment: Hypopituitarism
Harrison’s 18th Edition.
Hypothalamic, Pituitary, and Other Sellar Masses
Harrison’s 18th Edition.
Hypothalamic, Pituitary, and Other Sellar Masses
Harrison’s 18th Edition.
Features of Sellar Mass Lesions
Harrison’s 18th Edition.
Features of Sellar Mass Lesions
Harrison’s 18th Edition.
Features of Sellar Mass Lesions
Harrison’s 18th Edition.
Features of Sellar Mass Lesions
Harrison’s 18th Edition.
Screening Tests for Functional Pituitary Adenomas
Harrison’s 18th Edition.
Treatment: Transsphenoidal Surgery
Harrison’s 18th Edition.
Treatment: Transsphenoidal Surgery
Harrison’s 18th Edition.
Treatment: Prolactinoma
Harrison’s 18th Edition.
Treatment: Prolactinoma
Harrison’s 18th Edition.
Oral dopamine agonists (cabergoline and bromocriptine) are the mainstay of therapy for patients with micro- or macroprolactinomas.
Dopamine agonists suppress PRL secretion and synthesis as well as lactotrope cell proliferation.
Treatment: Growth Hormone
Harrison’s 18th Edition.
Causes of Acromegaly
Harrison’s 18th Edition.
Causes of Acromegaly
Harrison’s 18th Edition.
Management of Acromegaly
Harrison’s 18th Edition.
Management of Acromegaly
Harrison’s 18th Edition.
Somatostatin AnaloguesOctreotideLanreotide,Sandostatin-LAR is a sustained-release, long-
acting formulation of octreotide incorporated into microspheres that sustain drug levels for several weeks after intramuscular injection.
Management of Acromegaly
Harrison’s 18th Edition.
GH Receptor AntagonistPegvisomant antagonizes endogenous GH
action by blocking peripheral GH binding to its receptor.
ACTH Deficiency
Harrison’s 18th Edition.
The total daily dose of hydrocortisone replacement preferably should not exceed 25 mg daily, divided into two or three doses.
Prednisone (5 mg each morning) is longer-acting and has fewer mineralocorticoid effects than hydrocortisone.
Cushing's Syndrome (ACTH-Producing Adenoma)
Harrison’s 18th Edition.
Cushing's Syndrome (ACTH-Producing Adenoma)
Harrison’s 18th Edition.
Cushing's Syndrome (ACTH-Producing Adenoma)
Harrison’s 18th Edition.
Ketoconazole, an imidazole derivative antimycotic agent, inhibits several P450 enzymes and effectively lowers cortisol in most patients with Cushing's disease when administered twice daily (600–1200 mg/d).
Metyrapone (2–4 g/d) inhibits 11-hydroxylase activity and normalizes plasma cortisol in up to 75% of patients.
Mitotane (o,p′-DDD; 3–6 g/d orally in four divided doses) suppresses cortisol hypersecretion by inhibiting 11-hydroxylase
Other agents include aminoglutethimide (250 mg tid), trilostane (200–1000 mg/d), cyproheptadine (24 mg/d), and IV etomidate (0.3 mg/kg per hour).
Recommended