A 36-year-old woman is undergoing upper and lower gastrointestinal endoscopy due to abdominal pain, anorexia, and nausea, with intermittent vomiting and diarrhea for the past several months. She also has had fatigue and a 10-kg (22-lb) unintended weight loss during this time. Abdominal imaging studies have been unrevealing. The patient has no other medical conditions and takes no medications. She does not use tobacco, alcohol, or illicit drugs and has no known drug allergies. Physical examination in the endoscopy unit shows normal heart and lung sounds, mild diffuse abdominal tenderness, and no lower extremity edema. Propofol is administered in preparation for the endoscopy. Several minutes later, the patient suddenly becomes hypotensive. Temperature is 37.8 C (100 F), blood pressure is 66/40 mm Hg, pulse is 108/min, and respirations are 20/min. Oxygen saturation is 95% on room air. There is no wheezing or skin rash. Heart and lung sounds are normal. The hypotension fails to improve despite intravenous fluid boluses and epinephrine. Urgent laboratory results are as follows:
| Complete blood count | |
| Hemoglobin | 13 g/dL |
| Platelets | 200,000/mm3 |
| Leukocytes | 8,200/mm3 |
| Neutrophils | 60% |
| Eosinophils | 12% |
| Lymphocytes | 28% |
| Serum chemistry | |
| Sodium | 130 mEq/L |
| Potassium | 4.9 mEq/L |
| Chloride | 98 mEq/L |
| Bicarbonate | 20 mEq/L |
| Creatinine | 0.8 mg/dL |
| Glucose | 64 mg/dL |
Which of the following is the most likely underlying cause of this patient's cardiovascular collapse?
Acute adrenal insufficiency (adrenal crisis) | |
Etiology |
|
Clinical features |
|
Treatment |
|
AI = adrenal insufficiency. | |
This patient's presentation is most consistent with primary adrenal insufficiency (PAI) complicated by adrenal crisis. Her history of fatigue, weight loss, abdominal pain, anorexia, and gastrointestinal disturbance likely reflects PAI. PAI usually involves autoimmune destruction of all 3 layers of the adrenal cortex, leading to deficiency of mineralocorticoids (eg, aldosterone), glucocorticoids (eg, cortisol), and androgens. Therefore, common findings in chronic PAI include hyponatremia (hypovolemia-induced antidiuretic hormone secretion), hypoglycemia (cortisol deficiency), and peripheral eosinophilia (eosinophils are normally inhibited by corticosteroids), as seen in this patient.
Acutely stressful events (eg, surgery, endoscopy, injury, infection) in patients with chronic adrenal insufficiency can precipitate adrenal crisis, manifesting as severe hypotension and shock. Adrenal crisis in PAI appears to be mainly a manifestation of mineralocorticoid deficiency (hypoaldosteronism), given that it can occur even in patients taking physiologic doses of glucocorticoids. However, the resulting severe hypotension, often refractory to volume resuscitation and poorly responsive to vasopressors, is likely exacerbated by glucocorticoid deficiency because cortisol is needed to potentiate the effect of alpha-1 stimulation on peripheral vascular tone.
Treatment requires rapid volume repletion and glucocorticoid replacement (eg, intravenous dexamethasone or hydrocortisone); dexamethasone is often preferred because it does not interfere with plasma cortisol level that may be needed to confirm the diagnosis. Mineralocorticoid replacement (eg, fludrocortisone) requires several days to exert its sodium-retaining effects and is typically started after initial resuscitation.
(Choice A) Gram-negative sepsis can cause profound vasodilation and severe hypotension; however, it is less likely in the absence of fever and would not explain this patient's prior abdominal pain, anorexia, and weight loss, or current eosinophilia. Neisseria meningitis (a gram-negative coccus) has an affinity for the adrenal glands and can cause massive adrenal hemorrhage with adrenal crisis (ie, Waterhouse-Friderichsen syndrome), but the presentation would be acute without preceding chronic symptoms.
(Choice C) Propofol can cause cardiac suppression and hypotension, at least partly due to inhibition of sympathetic drive. However, propofol-induced hypotension cannot account for eosinophilia and hypoglycemia and would likely have improved with epinephrine administration.
(Choice D) Acute pulmonary embolism can cause severe hypotension and shock but would also cause significant hypoxemia.
(Choice E) Thyrotoxicosis (eg, excess T3 and/or T4) usually presents with hypertension and hyperglycemia.
Educational objective:
In patients with underlying chronic adrenal insufficiency, acute stressors (eg, procedure, illness, trauma) can trigger adrenal crisis, which presents with hypoglycemia and severe hypotension often refractory to initial volume resuscitation. Treatment requires rapid volume repletion and administration of hydrocortisone or dexamethasone.