Introduction to Endocrinology. Hypothalamic and Pituitary diseases Prolactinoma + Acromegaly Dr. Peter Igaz MD PhD DSc 2nd Department of Medicine Semmelweis University
Fields of Endocrinology Diseases of the pituitary (Hypothalamus) Thyroid Parathyroid Adrenal diseases Gonads/reproductive endocrinology Diabetes mellitus Multiple endocrine Neoplasias Autoimmune polyendocrine syndromes
Principles of Endocrinology Primary vs. Secondary (pituitary) dysfunctions (Tertiary) First laboratory investigations, then imaging
Causes of hypothalamic dysfunction Tumors (astrocytoma, glioma, germinoma, craniopharyngeoma, large pituitary tumor, lymphoma) Haemorrhages Developmental abnormalities (arachnoideal cyst, holoprosencephaly) Granulomatous inflammation (histiocytosis X, sarcoidosis, TBC) inflammation (encephalitis, meningitis) Trauma Irradiation Hereditary diseases
Diseases of the hypothalamus Deficiency of trophormones (CRH, TRH, GnRH, GHRH) growth failure, hypopituitarism, disorders of sexual development (isolated GnRH-deficiency Kallmann-syndrome) Deficiency of posterior pituitary hormones Non-endocrine consequences of hypothalamic damage: Feeding disorders (anorexia, hyperphagia, obesitas) Disorders of fluid intake (adipsia, polydipsia) Disorders of thermoregulation (hyperthermia, hypothermia) Somnolentia, coma, lightmindedness Mood lability
Hypothalamic forms of obesity Dystrophia adiposogenitalis (Fröhlichsyndrome) obesity, hypogonadism, visual disturbances, skeletal malformations, white skin, intracrnaial tumor Laurence-Moon-Biedl syndrome (AR, 1:160.000) Laurence-Moon: obesity, spastic paraparesis, retinitis pigmentosa, mental retardation, hypogonadis Biedl-Bardet: polydactily, retinitis pigmentosa, mental retardation, hypogonadism, renal malformations Prader-Willi-Labhart syndrome
Diseases of the pituitary Adenomas (Micro-, Macro-, Incidentaloma) Anterior pituitary Hormone overproduction (60-70%) Prolaktin GH ACTH TSH (very rare) Hormonally inactive pituitary tumors (also the gonadotropin-secreting) (30-35%) Hypopituitarismus Posterior pituitary Diabetes insipidus SIADH
Limit: 10 mm Micro- and Macroadenoma Consequences: Hormone overproduction Mass effects Vision loss Hormon losses (1. GH, 2. LH/FSH, 3. TSH, 4. ACTH) increased Prolactin (Stalk lesion) Intracranial hypertension Neurological Complications Mostly benign, pituitary cancer is extremely rare, defined by the presence of intracerebral metastases
Frequency of pituitary adenomas Pituitary tumors are the most prevalent intracranial neoplasms Prevalence 77/100.000 1. Prolactinoma 2. Hormonally inactive tumors (gonadotropin secretion without clinical consequences) 3. GH 4. PRL + GH 5. Cushing-disease 6. TSH (Incidence: 1-2/10 Million/year)
Pituitary incidentaloma Definition: Pituitary adenomas discovered by brain imaging MRI (or CT) that was not indicated with the suspicion of pituitary disease (similar definition for adrenal incidentaloma) Very frequent, about 10 % of the population has pituitary incidentalomas on MRI (Inhomogenities of the pituitary) Mostly hormonally inactive microadenomas without clinical relevance
Examination of pituitary adenomas Hormonal Work-up - Screening Prolactin Cortisol, ACTH TSH, ft4 IGF-1 LH, FSH, Sexual steroids Imaging (MRI) Ophtalmological examination
Treatment of pituitary adenomas Surgery Macroadenomas, Vision loss, neurological complications, Liquorrhoea, Hormone overproduction (with the exception of most prolactinomas) Medical treatment (Prolactinoma, Acromegaly) Irradiation (gamma-knife)
Prolactinoma The most common form of pituitary adenoma Microprolaktinoma vs. Macroprolaktinoma (Limit 10 mm) Prevalence 44/100.000 Characteristic Symptoms in women, often without symptoms in elderly men
Symptoms of Prolactinoma Women Galactorrhoea Amenorrhoea/ Raromenorrhoea Osteoporosis Men Loss of libido Impotence Osteoporosis Mass effects both genders Vision loss Hormone losses Neurological complications
Normal Prolactin levels Normal range: 5-20 ng/ml Prolaktin levels associated with Prolactinoma are mostly >200 ng/ml. In case of macroprolactinoma, PRL is usually >1000 ng/ml. Hook-Effect in case of very high PRL levels, laboratory measurement can be falsely negative Macroprolactin prolactin polymers nonfunctional, false positive results PEG-Reaction is needed to exclude it
Other causes of hyperprolactinemia Drugs Pituitary lesions (Trauma, Surgery, large tumors (Macroadenomas), infiltrative lesions /e.g. sarcoidosis/) Estrogen Hypothyroidism Trauma or irritation of the thoracic wall Chronic renal insufficiency
Drugs causing hyperprolactinemia Dopamin-antagonists (D2-Receptor Antagonists) Antipsychotic Drugs Risperidone Antidepressives Antiemetic drugs e.g. Metoclopramide Antihypertensive drugs (Verapamil, Reserpin, Methyldopa)
Macroprolactinoma
Treatment of Prolactinoma Drug treatment Dopamin Agonists Bromocriptin Ergot-Derivative Quinagolid Cabergolin - Ergot-Derivative Surgery threatening vision loss, neurologic consequences, ineffective drug treatment, missing compliance Irradiation
Acromegaly and Gigantism Rare disease Prevalence: 30-70/Million
Symptoms of Acromegaly Growth of the Acras : Hands (Sausage fingers), Legs, Nose, tongue (Macroglossia), Ears, Lips, Carpal Tunnel syndrom Hand shoe size? Shoe size? Visceromegaly (Cardiomegaly) Hypertension, Heart insufficiency, Sleep apnoe Increased tumor incidence Colon polyposis, Colorectal Cc. Sweating Diabetes mellitus Endocrine dysfunctions (Raromenorrhoea, Impotence)
Death causes in acromegaly Cardiovascular (Heart insufficiency) 60% Respiratory (25 %) Tumor disease (15%)
Laboratory diagnosis of Acromegaly Screening Serum IGF-1 Confirmation- OGTT (Oral glucose tolerance test) 75 g Glucose per os, Blood taken at 0, 30, 60, 90, 120, 180 Normally GH goes below 1 ng/ml, in acromegaly it remains over 2 ng/ml, and a paradoxical increase of GH can even be observed
Treatment of acromegaly 1. Surgery Success rate for microadenomas: 70-90% Success rate for macroadenomas: 50-70% 2. Drug treatments Somatostatin Analogues (Octreotid, Lanreotid, Pasireotid) GH-Receptor antagonist, Pegvisomant (Somavert) Dopamin agonists (Cabergolin) 3. Irradiation