Endocrine Physiology: Case Studies in Adrenal Disorders

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Endocrine Physiology Case Studies in Adrenal
Disorders

• C.W. Spellman, PhD, DO
• Assoc. Prof. Medicine
• Assist. Dean, Dual Degree Program
• Head, Endocrinology Dir. Diabetes Clinics
• UNTHSC

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Reference Lab Values for Cases

• Glucose 60 -110 mg/dL
• Na 136 -144 mEq/dL
• K 3.8 - 5.4 mEq/dL
• HCO3 23 - 26 m Eq/dL
• BUN 8 - 14 mg/dL
• Creatinine 0.6 - 1.5 mg/dL
• Calcium 8.5 - 10.5 mg/dL
• Hb 13.5-15.5 g/dL

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Reference Values, cont.

• ACTH 10 - 75 pg/ml
• TSH 0.3 - 5.0 mIU/ml
• a.m. Cortisol 5 - 25 ?g/dl
• ACTH Stim. cortisol 18 - 20 ?g/dl or
• ?7 ?g/dl baseline
• 24 h urine free cortisol 10 - 50 ug/24 hr
• Aldosterone
• Aldosterone renin

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Cushings Syndrome

• Cushings syndrome
• Excess glucocorticoids due to
• Pituitary tumor 70 - 80
• Adrenal tumor 10 - 20
• Ectopic ACTH tumor 10
• Iatrogenic
• Classic syndrome
• Weight gain, Plethora, Striae, HTN,
• Proximal muscle weakness

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Clinical Features of Cushings Syndrome

• Weight gain 90 ? Menses 60
• Moon face 75 Acne 40
• HTN 75 Bruising 40
• Striae 65 Osteopenia
  40
• Hirsuitism 65 Edema 40
• Glucose intol 65 Hyperpig. 20
• Muscle weak. 60 K meta. alk. 15
• Plethora 60

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Case 1 Young Lady With Weight Gain

• A 24 y lady was in good health in the Spring of
  1999. She married in August and her husband
  brought her to the Endocrine clinic in December.
  
• Complaints
• 80 lb weight gain
• Fatigue
• Stretch marks
• Shortness of breath

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Case 1, cont.

• PE BP180/100 HR84 RR20 T99
• Ht65 Wt250 lbs
• HEENT ? buccal fat
• Neck ? dorsal fat
• Chest ? supraclavicular
• Lung CTA
• Cor RRR, no S3 or S4, normal PMI
• Abd Obese
• Extrem Thin, prox. muscle weakness
• Skin Wide red striae, ecchymoses
• Neurol normal

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Case 1, cont.

• Lab evaluations
• Na 136
• K 3.6
• Gluc 190
• Cr 0.9

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Case 1, Questions

• What do you think the diagnosis is?
• If the lesion was in the pituitary, predict
• ACTH
• Cortisol
• If the disease was in the adrenals, predict
• ACTH
• Cortisol
• If the lesion was an ectopic tumor, predict
• ACTH
• Cortisol

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Case 1, Questions

• How could you determine if this lady had adrenal
  disease? Pituitary tumor? Ectopic tumor?
• Why is the glucose elevated?
• Why is she weak?
• What are the skin changes due to?
• Why has she gained weight?
• Why is the potassium low?

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Clinical Features of Primary Adrenal Insufficiency

• Gradual onset 95
• Weakness fatigue 100
• Wt loss/anorexia 100
• Hyperpigmentation 92
• Hypotension / tachycardia 88
• Hyponatremia 88
• Hyperkalemia 64
• Muscle, GI pain 56

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Clinical Features of Secondary Adrenal
Insufficiency

• Gradual onset 95
• Weakness fatigue 100
• Wt loss/anorexia 100
• Pale 100
• Hair loss
• Anemia
• Electrolytes usually normal

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Case 2 Medical Student with Weakness, Fatigue
and Nausea

• 25 y 2nd y medical student develops weakness,
  fatigue and nausea. She is unable to complete
  the OB-GYN rotation.
• The OB attending briefly evaluates the student,
  suspects and endocrine problem and refers her to
  our clinics.

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Case 2, cont

• PE BP90/60 HR96 RR16 T98
• Ht68 Wt 130 lbs
• HEENT nor
• Neck nor
• Lung nor
• Cor nor
• Abd nor
• Extrem nor
• Skin uniformly tan
• Neurol nor

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Case 2, cont

• Lab
• Na 124
• K 5.9
• Glucose 70
• TSH 1.55
• Hb 15.4

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Case 2, Questions

• What do you think the diagnosis is?
• If the lesion was in the adrenals, predict
• Cortisol
• Aldosterone
• ACTH
• Why is the sodium low?
• Why is the potassium high?
• If the lesion was in the pituitary, predict
• Cortisol
• Aldosterone
• ACTH

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Case 2, Questions

• If the patient had secondary disease, how would
  the physical examination have been different?
• If the patient had secondary disease, how would
  the electrolytes have been different?

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Aldosteronism

• Old name Conns syndrome
• 2x more common in ? than ?
• Occurs 30 50 y age group
• Si/Sx
• Diastolic HTN
• Headache
• Hypokalemia
• LVH occurs
• Renal disease
• 50 develop proteinuria
• 15 develop renal failure

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Aldosteronism

• Older data suggest that aldosteronism
• New data suggest that up to 10 of HTN is due to
  aldosteronism
• Suspect aldosteronism
• Diastolic HTN
• Hypokalemia (K 3 meq/L)

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Causes of Aldosteronism

• Aldosterone-producing adenoma
• 75 of cases of aldosteronism
• Usually solitary nodules (0.5 - 2.5 cm)
• Almost always benign

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Causes of aldosteronism

• Adrenocortical hyperplasia
• a. 25 of cases of aldosteronism
• b. Bilateral hyperplasia
• c. Rarely produces hormones other than
  aldosterone

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Causes of Aldosteronism

• Other causes
• 1. Adrenal carcinoma is extremely rare
• 2. Congenital adrenal hyperplasia
• Produces mineralocorticoids
  other than aldosterone
• 3. Secondary aldosteronism
• High aldosterone is secondary to high
  renin levels

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Case 3 Young Man with Hypertension

• A 25 y male presents to the clinic as a new
  patient. He takes no prescription medications,
  over-the-counter products or alternative
  substances
• He came because his wife, a PA, noted
  hypertension and scheduled the visit

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Case 3, cont.

• PE BP170/104 HR72 RR16 T98
• Ht72 Wt195 lbs
• HEENT nor
• Neck nor
• Chest nor
• Abd nor
• Extrem nor
• Skin nor
• Neurol nor

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Case 3, cont.

• Lab
• CMP normal, except K2.9
• TSH nor

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Case 3, Questions

• What do you think the diagnosis is?
• How common is this disorder?
• Predict the laboratory results of
• Aldosterone
• Renin
• Cortisol
• Why does this patient have hypertension?
• Why is the potassium low?

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Case 3, Questions

• What are possible causes of the problem?
• Discuss primary causes
• Discuss secondary causes
• How would you differentiate primary from
  secondary causes?
• Can you illustrate the physiology of primary and
  secondary disease?

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Secondary Aldosteronism

• Secondary aldosteronism refers to appropriate
  increased production of aldosterone in response
  to activation of the renin-angiotensin system

Primary aldosteronism
Secondary Aldosteronism
? Vol
? Vol
? Renin
? Na
? Renin
? Na
? Aldo
? Aldo