Anterior and posterior lobe pituitary hypofunction. Syndrome of inappropriate antidiuretic hormone secretion (SIADH)

Transcription

1 Anterior and posterior lobe pituitary hypofunction Syndrome of inappropriate antidiuretic hormone secretion (SIADH) Miklós Tóth Professor of Medicine and Endocrinology 5 February, 2018 Semmelweis University 2nd Department of Medicine

2 Pituitary disorders Pituitary hypofunction - anterior lobe - posterior lobe Pituitary masses - functioning tumors - non-functioning tumors

3 Anatomy of the sellar region

4 Inherited pituitary insufficiency Williams, Textbook of Endocrinology, 13th ed, Table 8-1

5 Causes of Acquired Pituitary Insufficiency Traumatic Infiltrative/Inflammatory Infections Vascular Neoplastic Functional

6 Causes of Acquired Pituitary Insufficiency Traumatic 1.Surgical resection 2.Radiation damage 3.Traumatic brain injury Infiltrative/Inflammatory 1.Primary hypophysitis 2.Lymphocytic 3.Granulomatous 4.Xanthomatous 5.Secondary hypophysitis 6.Sarcoidosis 7.Histiocytosis X 8.Infections 9.Wegener granulomatosis 10.Takayasu disease 11.Hemochromatosis Infections 1.Tuberculosis 2.Pneumocytis jirovecii infection 3.Fungal (histoplasmosis, aspergillosis) 4.Parasites (toxoplasmosis) 5.Viral (cytomegalovirus) Vascular 1.Pregnancy-related 2.Aneurysm 3.Apoplexy 4.Diabetes 5.Hypotension 6.Arteritis 7.Sickle cell disease Neoplastic 1.Pituitary adenoma 2.Parasellar mass 3.Rathke s cyst 4.Dermoid cyst 5.Meningioma 6.Germinoma 7.Ependymoma 8.Glioma 9.Craniopharyngioma 10.Hypothalamic harmatoma, gangliocytoma 11.Pituitary metastatic deposits 12.Hematologic malignancy 13.Leukemia 14.Lymphoma Williams, Textbook of Endocrinology, 13th ed, Table 8-1 Functional 1.Nutritional 2.Caloric restriction 3.Malnutrition 4.Excessive exercise 5.Critical illness 6.Acute illness 7.Chronic renal failure 8.Chronic liver failure 9.Hormonal 10.Hyperprolactinemia 11.Hypothyroidism 12.Drugs 13.Anabolic steroids 14.Glucocorticoid excess 15.GnRH agonists 16.Estrogen 17.Dopamine 18.Somatostatin analogue 19.Thyroid hormone excess

7 Causes of acquired GH deficiency in 1034 hypopituitary adult patients Pituitary tumor 53.9% Craniopharyngioma 12.3% Idiopathic 10.2% CNS tumor 4.4% Empty sella syndrome 4.2% Sheehan syndrome 3.1% Head trauma 2.4% Hypophysitis 1.6% Surgery * 1.5% Granulomatous diseases 1.3% Irradiation * 1.1% CNS malformation 1.0% Perinatal trauma or infection 0.5% Other 2.5% Abs R et al, Clin Endocrinol, 1999

8 Pituitary hypofunction ACTH deficiency TSH deficiency GH deficiency Gonadotropin deficiency (both LH and FSH) Prolactin deficiency Arginin-vasopressin deficiency

9 Prevalence of GH deficiency in patients with pituitary disorders Jameson, De Groote, 7th Ed, Figure 11-8

10 Varying sensitivity of pituitary axes following radiotherapy Jameson, De Groote, 7th Ed, Table 18-4

11 Summary of clinical features of hypopituitarism Hormone deficiency Presentation Adrenocorticorticotrophic hormone Gonadotrophins Thyroid-stimulating hormone Growth hormone Prolactin Antidiuretic Hormone Acute Symptoms and signs Fatigue, weakness, dizziness, nausea, vomiting, circulatory failure. As in Addison's disease, except lack of hyperpigmentation, absence of hyperkalaemia Chronic Tiredness, pallor, anorexia, nausea, weight loss, myalgia, hypoglycaemia Children Delayed puberty Men Women Impaired fertility, impotence, reduced libido, decreased muscle mass and strength, decreased bone mass, decreased erythropoiesis and hair growth, fine wrinkles, testicular hypotrophy Amenorrhoea, oligomenorrhoea, infertility, loss of libido, dyspareunia, fine wrinkles, breast atrophy, osteoporosis, premature, atherosclerosis Children Growth retardation Adult Fatigue, cold intolerance, constipation, weight gain, dry skin, slow relaxing reflexes Children Growth retardation, short stature, increased adiposity Adult Reduced exercise capacity, impaired psychological wellbeing, increased cardiovascular risk, increased central obesity, reduced lean body mass Failure of lactation Polyuria, polydipsia including nocturnal

12 Baseline investigation of pituitary (hypo)function 1. Adrenocortical axis: serum cortisol 2. Thyroid axis: total T4 or free T4, TSH 3. Gonadal axis: men - testosterone, SHBG, LH, FSH women - oestradiol, LH, FSH, progesterone (day 21 if menstruating) 4. Prolactin 5. Insulin-like growth factor-1 6. Paired plasma and urine osmolality

13 Signs and symptoms of ACTH deficiency ~ glucocorticoid deficiency fatigue generalized weakness loss of appetite weight loss anorexia nausea hypotension

14 Laboratory diagnosis of glucocorticoid deficiency Baseline tests Morning basal plasma cortisol 5 g/dl ( 140 nmol/l) grey zone 18 g/dl ( 500 nmol/l) confirms GC deficiency 5-18 g/dl ( nmol/l) excludes GC deficiency Plasma ACTH high in primary hypadrenia low in secondary hypadrenia Bronstein, J Clin Endocrinol Metab 101: , 2016

15 Laboratory diagnosis of glucocorticoid deficiency Dynamic tests Indication baseline se. cortisol within the grey zone Adrenal stimulation Short ACTH-test (250 µg ACTH-[1-24]-tetracosactid) cut-off value: µg/dl ( nmol/l) Hypothalamic testing insulin induced hypoglycemia stimulates ACTH and GH secretion Bronstein, J Clin Endocrinol Metab 101: , 2016

16 Treatment of ACTH deficiency Chronic maintenance therapy hydrocortisone, per os, mg/day in 2-3 proportions/day cortisone acetate, mg/day Supplemental hydrocortisone therapy increased oral doses during minor disease administration of im. hydrocortisone Treatment of hypadrenic crisis bolus hydrocortisone + slow iv. infusion mg /day

17 Acute adrenal crisis

18 Signs and symptoms of TSH deficiency = thyroid hormone deficiency mental and growth retardation fatigue loss of memory weight gain high blood pressure constipation cold intolerance fluid retention hair loss

19 Treatment of TSH deficiency levothyroxine, per oral partial deficiency: Daily dose complete deficiency: ug/day ug/day Monitoring: clinical symptoms + serum ft4 levels

20 Clinical consequence of adult somatotropin deficiency Body Composition General and central adiposity Reduced lean mass Reduced bone mass Function Reduced exercise capacity Muscle weakness Impaired cardiac function Hypohydrosis Quality of Life Low mood Fatigue Low motivation Reduced satisfaction Cardiovascular Risk Profile Abnormal lipid profile Insulin resistance Increased inflammatory markers Intimal media thickening Laboratory Blunted peak GH to stimulation Low IGF-1 (in 50-60%) Hyperinsulinemia High LDL and low HDL cholesterol

21 Male patient before and 5 years after acquiring GH deficiency Jameson, De Groote, 7th Ed, Figure 11-6

22 Diagnosis of GH deficiency Screening IGF-1 has restricted usefulness IGF-1 is normal in 20% of males wiith GH def Confirmatory tests Insulin tolerance test (insulin-induced hypoglycemia test) GH-RH-arginin test Glucagon test Fleseriu, J Clin Endocrinol Metab 101: , 2016

23 Insulin-induced hypoglycemia test INDICATIONS Assessment of ACTH and cortisol reserve Assessment of GH reserve in children with definite growth retardation Assessment of GH response in adults Differentiation of Cushing's syndrome from depression (rarely needed) CONTRAINDICATIONS Ischaemic heart disease Epilepsy or unexplained blackouts Untreated hypothyroidism (impairs GH and cortisol response). Severe longstanding hypoadrenalism (liver glycogen stores are depleted, causing severe hypoglycaemia during the ITT) / Serum cortisol <100nmol/L Glycogen storage disease

24 Insulin-induced hypoglycemia test PREPARATIONS Fast overnight (water permitted); perform test recumbent. Discontinue hydrocortisone 24 hours (or at least prior 2 doses) Medications can be given after completion of the test ie by lunchtime. Calculate Actrapid Insulin dose: Usual dose 0.15 U/kg Acromegaly, type 2 diabetes, Cushing's 0.3 U/kg 50 mls 50% dextrose must be available for immediate administration (but only use if persistent severe hypoglycaemia). If this is required, continue sampling!

25 Insulin-induced hypoglycemia test PROCEDURE Site indwelling cannula. At 0 minutes, take baseline bloods and then inject insulin i.v. Take samples for GH, cortisol and glucose (check glucose on glucometer with each sample) at 0, 30, 45, 60, 90, and 120 mins, flushing the cannula with saline between samples. At 30 minutes check whole blood glucose with Glucometer and repeat the insulin dose if not hypoglycaemic (this will mean prolonging sampling by 30 min). If insulin dose repeated: restart the clock and collect at t= 0, 30, 45, 60, 75, 90, 120, 150 mins. Adequate hypoglycaemia ( 2.2mmol/l) necessary. Record symptoms in the notes. There must be at least 2 specimens following adequate hypoglycaemia. Patient need not be hypoglycaemic throughout. Lowest glucose level following IV insulin is usually at minutes, with spontaneous resolution. Obtain specimen for glucose before reversal. If needed, reverse hypoglycaemia orally (juice/lucozade). If severe/patient unrousable consider i.v. 20% dextrose (10-15 ml) or 1 mg i.m. glucagon (1 amp), and continue sampling. If patient has a hypoadrenal crisis give i.v. 0.9% saline and hydrocortisone 100 mg. Once test completed, give supervised meal. Patient should not drive for 2 hours after the test.

26 Insulin-induced hypoglycemia test INTERPRETATION The test cannot be interpreted unless hypoglycaemia ( 2.2mmol/l) is achieved. Adequate cortisol response is defined as a rise to above 500 nmol/l. Patients with normal cortisol response (as defined above) can withstand major surgery without steroid replacement. Patients with satisfactory basal values (>250 nmol/l) but subnormal stimulated values require cover for major illnesses and surgery and carry a steroid card and/or MedicAlert bracelet. All other patients with subnormal responses require hydrocortisone replacement Adequate GH response is a rise >6 ng/ml Severe GH deficiency is defined GH peak < 3 ng/ml In children a rise to greater than 12 ng/ml is considered normal.

27 Management of adult GH deficiency Williams, Textbook of Endocrinology, 13th ed, Table 8-1

28 Side effects of adult growth hormone treatment Edema Arthralgia Myalgia Muscle stiffness Paresthesias Carpal tunnel syndrome Atrial fibrillation Headache Benign intracranial hypertension Hyperglycemia Sleep apnoe Iatrogenic acromegaly

29 Frequency of T2DM and cancer in patients with GHRD Jameson, De Groote, 7th Ed, Figure

30 Clinical features of male hypogonadotropism Prepubertal onset Postpubertal onset high-pitched voice decreased libido absent terminal facial hair decreased spontaneous erections absent/decreased body hair slow beard growth eunochoidal body proportions decreased body hair female escutcheon testicular atrophy if long standing testicular volume < 6 cm 3 decrased muscle and bone mass testicular length < 2.5 cm cryptorchidism may be present penile length < 5 cm hypopigmented scrotum, absent rugae small prostate decresed libido decreased muscle and bone mass

31 Managment of male hypogonadotropism Goals of therapy replace or restore sex steroid hormones maintain normal reproductive functions

32 Treatment of gonadotropin deficiency in males Testosterone substitution - oral, transdermal, intramuscular testosteron preparation Induction of spermatogenesis - hcg, LH-/FSH preparations

33 Androgen replacement therapy in men Intramuscular injections testosterone enanthate, testosterone cypionate Transdermal preparations gel and patch systems Oral preparations testosterone undecanoate Side effects acne, gynecomastia, prostatic hypertrophy reduced fertility hepatotoxicity, polycythemia Absolute contraindication prostate cancer

34 Induction of spermatogenesis Human chorionic gonadotropin (hcg), im IU, two to three times a week for months Human menopausal gonadotropin or purified FSH, im 75 IU three times a week Alternative: pulsatile GnRH therapy continous mini-pump

35 Diabetes insipidus Large volume of urine Dilute and tasteless = diabetes = insipid Absence vasopressin Inadequate response to vasopressin Four syndromes of diabetes insipidus central diabetes insipidus nephrogenic diabetes insipidus diabetes insipidus of pregnancy primary polydipsia lack of AVP lack of response to AVP increased metabolism of AVP normal AVP effect

36 Diabetes insipidus Diagnosis of polyuria collect and measure 24-hour urine keep a diary for 24 hours record volume and time of each voided urine record volume of fluid intake Severity of polyuria mild: moderate: severe: ml/day ml/day > 7000 ml

37 Diagnostics of diabetes insipidus I. Water deprivation test measured parameters (every 2-3 hours) body weight urinary volume serum and urinary osmolality after 8 h, administer 2 µg desmopressin Stop test, if body weight loss > 3% or serum osmolality > 305 mosm/kg every hour every hour every 2-3 hours Fleseriu, J Clin Endocrinol Metab 101: , 2016

38 Diagnostics of diabetes insipidus II. Diagnostic criteria of diabetes insipidus despite high serum osmolality (> 295 mosmol/l) urinary osmolality < 600 mosmol/l Differentiation between central and nephrogenous diabetes insipidus after administering desmopressin urinary osmolality > 800 mosmol/l - central DI < 300 mosmol/l - nephrogenous DI in case of partial concentration further testing needed Fleseriu, J Clin Endocrinol Metab 101: , 2016

39 Imaging in central diabetes insipidus Hypothalamic-pituitary MRI posterior pituitary bright signal on T1-weighted MRI sellar tumors, most often craniopharyngeomas stalk mass germinoma, lymphocytic hypophysitis, metastasis, etc

40 Treatment of central diabetes insipidus Desmopressin intranasal 5-20 µg/day, bid per os µg/day, bid Side effects / overtreatment water intoxication, hyponatraemia Preferred approach to chronic treatment slight undertreatment being compensated by normal thirst mechanisms

41 Hypothalamic diabetes insipidus Congenital Acquired Hereditary (X-linked or autosomal dominant), DIDMOAD Pituitary surgery Tumors (craniopharyngioma, germinoma, pinealoma metastases) Traumatic brain injury Granuloma (TB, sarcoid, histiocytosis X) Infections (encephalitis, meningitis) Vascular disorders (Sheehan s syndrome, aneurysms, subarachnoid hemorrhage, GI bleed) Hypophysitis (A/immune, lymphocytic) Idiopathic Pregnancy

42 Nephrogenic Diabetes Insipidus Congenital Acquired Hereditary (X-linked recessive or autosomal dominant) Chronic renal disease (polycystic kidneys, obstructive uropathy) Metabolic disease (hypercalcemia, hypokalemia) Drugs (lithium, demeclocycline) Osmotic diuresis (glucose, mannitol) Amyloidosis Myelomatosis Dipsogenic Diabetes Insipidus Compulsive water drinking Affective disorders (e.g., schizophrenia) Craniopharyngioma/Rathke s cleft cyst Sarcoidosis

43 Primary polydipsia Synonyms: dipsogenic diabetes insipidus psychogen polydipsia Causes: psychiatric disorders: schizophrenia, drugs that cause dry mouth habitual throughout a lifetime

44 Syndrome of inappropriate antidiuretic hormone secretion SIADH Inappropriate overproduction of ADH. Definition: SIADH is a condition when plasma levels of AVP are elevated at times when the physiologic secretion of vasopressin from the posterior pituitary would normally be osmotically suppressed. The hallmark of SIADH is hypoosmolality.

45 Plasma AVP levels in patients with SIADH Williams, Textbook of Endocrinology, 13th ed, Figure 10-6

46 Symptoms of hypoosmolality ~ hyponatremia Jameson, De Groote, 7th Ed, Table 112-1

47 Etiology of SIADH Jameson, De Groote, 7th Ed, Table 18-4

48 Causes of hyponatremia Jameson, De Groote, 7th Ed, Table 112-2

49 Most important diagnostic criteria of SIADH Serum osmolality <275 mosm/kg H 2 O Urinary osmolality >100 mosm/kg H 2 O Urinary sodium > 20(-30-40) mmol/liter Clinical euvolemia Euadrenia and euthyreosis Absence of use of diuretics Exclusion of hypocortisolism and hypothyroidism

50 Therapy of SIADH Hypertonic saline Isotonic saline Fluid restriction AVP antagonists Urea Furosemide and NaCl Williams, Textbook of Endocrinology, 13th ed, Figure 10-6

51 Antagonizing the effect of AVP Non-specific antagonists lithium demeclocyclin Peptid antagonists Non-peptid antagonists VPA-985 (lixivaptan) YM-087 (conivaptan) OPC tolvaptan - Samsca SR satavaptan - Aquilda

52 Differential diagnosis of SIADH Glucocorticoid deficiency Hypothyroidism Chronic renal disorder Cardiac decompensation Liver cirrhosis Jameson, De Groote, 7th Ed, Figure 18-8

53 Köszönöm a figyelmet!