Addison’s Disease Case Studies This 32-year-old white professional female was noted to have increasing melanosis affecting her skin and gums. She noted that she had become weaker over the past several weeks. She complained of nausea, occasional vomiting, and anorexia. She experienced a 10-pound weight loss in the last 8 weeks. She complained of a relative recent onset of moderate high-back pain. She has noted constipation but has no other gastrointestinal symptoms. She noted early satiety. Over the last 2 years she has developed Reynaud’s phenomena. Her physical exam reveals a thin woman with a dark tan (she recently returned from a vacation in the Caribbean). She weighed 90 lbs and was 5’2” tall. She had very little axillary hair but had all normal primary and secondary sexual characteristics. There was evidence of a melanotic gum line around her teeth. The creases of her hands were hypermelanotic. The remaining physical examination was normal. Studies Results CBC, Normal Chemical profile Normal except: Na = 129 (normal: 136-145 mEq/L) K = 5.1 (normal: 3.5-5 mEq/L) Albumin 3.0 (normal: 3.5-5 g/dL) EGD Mild gastritis Gastric Emptying Delayed gastric emptying CT Scan Abdomen Adrenal glands not visible CT Scan of the Brain No pituitary tumor Cortisol 8 AM 2 mcg/dL (normal: 5-23 mcg/dL) ACTH 8 AM 3,200 pg/mL (normal: <80 pg/mL) Aldosterone 10 ng/dL (normal: 5-30 ng/dL) 21 hydroxylase antibodies 5 Units/mL (normal: < 1 Units/mL) ANA Positive 1:120 (normal: negative at 1:40 dilution) Case Studies 2 T4 (Free), p. 497 2.5 ng/dL (normal: 0.8-2.8 ng/dL) TSH, p. 486 4 microUnits/mL (normal: 2-10 microUnits/mL) Diagnostic Analysis With the low cortisol level, the diagnosis of Addison disease was made. Her ACTH was high, indicating secondary adrenal failure. ACTH has actions comparable to melanocytic-stimulating hormone thus causing hyperpigmentation, and elevated levels of ACTH caused this woman to be very darkly tanned. No pituitary tumor was found indicating that this was primary adrenal failure. Her elevated ANA and hydroxylase antibodies indicated that she had an autoimmune cause of her Addison’s disease. The small or absent adrenal glands noted on CT scan corroborated autoimmune destruction of her adrenal glands. Although one of her main presenting symptoms was upper GI dysfunction, no pathology, such as peptic disease, was found. Her reduced gastric transit was caused by her Addison disease. Critical Thinking Questions 1. Of all the tests this young woman had, which single test would be easiest, most diagnostic, and would have explained her entire symptom complex? 2. What are some of the other adrenal function tests that could have been performed to assist in the diagnosis of this woman’s adrenal failure? 3. What is the difference between primary and secondary Addison disease, and how can the two be separated? 4. Why was this woman’s sodium low and her potassium elevated?