Adrenal Disorders in Pregnancy

Adrenal Physiology in Pregnancy - Hormonal Hullabaloo

• HPA Axis: Negative feedback largely intact. Placental CRH ↑, especially in late pregnancy.
• Cortisol: Total cortisol ↑ significantly (2-3x) due to estrogen-driven ↑ Cortisol Binding Globulin (CBG). Free cortisol remains normal or slightly ↑. Diurnal rhythm is maintained but blunted.
• CBG (Transcortin): ↑ due to estrogen, leading to ↑ total cortisol carrying capacity.
• Aldosterone: ↑ progressively (RAAS activation; progesterone antagonism). Levels can be 5-10x non-pregnant values by term.
• DHEAS: ↓ during pregnancy, partly due to ↑ placental clearance and conversion to estrogens.

⭐ Pregnancy is a state of physiologic hypercortisolism due to increased estrogen stimulating Cortisol Binding Globulin (CBG) production, leading to higher total cortisol but normal or slightly elevated free cortisol.

Cushing's Syndrome in Pregnancy - Cortisol Chaos

• Etiology: Adrenal adenoma most common; pituitary (Cushing's disease) rare.
• Clinical Features: Overlap with pregnancy (weight gain, striae). Specific: proximal myopathy, easy bruising, facial plethora, HTN, new glucose intolerance.
• Diagnostic Challenges & Tests (Interpretation in Pregnancy):
  • 24-hr UFC: Normal pregnancy (mild ↑); Cushing's (markedly ↑, >3x non-preg ULN).
  • Late-night salivary cortisol: Normal pregnancy (stable/slight ↑); Cushing's (significantly ↑).
  • LDDST (1mg): Normal pregnancy (variable suppression); Cushing's (no suppression, cortisol >1.8 µg/dL or 50 nmol/L).
  • ACTH: Low in adrenal adenoma.
• Maternal Complications: GDM, preeclampsia, infections.
• Fetal Complications: IUGR, preterm birth, neonatal adrenal suppression.
• Management: Surgery (adrenalectomy, 2nd tri. ideal for adenoma) or Metyrapone (preferred).

⭐ The most common cause of Cushing's syndrome during pregnancy is an adrenal adenoma; pituitary causes (Cushing's disease) are rare.

Adrenal Insufficiency in Pregnancy - Energy Emergency

• Types & Causes:
  • Primary (Addison's): Autoimmune, TB.
  • Secondary: Pituitary dysfunction, chronic steroid withdrawal.
• Clinical Features: Hypotension, fatigue, nausea/vomiting, weight loss. Hyperpigmentation (primary, may be subtle if recent onset).
• Diagnosis: ↓AM cortisol, ↑ACTH (primary). ACTH stimulation test: post-ACTH cortisol <18-20 mcg/dL or <500 nmol/L.
• Management:
  • Glucocorticoid (e.g., Hydrocortisone) & Mineralocorticoid (Fludrocortisone for primary) replacement.
  • Stress Doses: Crucial for labor/delivery/illness. Hydrocortisone 50-100mg IV/IM q6-8h during labor.
• Adrenal Crisis: Precipitated by stress/infection. Severe hypotension, shock, hypoglycemia.
  • Manage: IV fluids (Normal Saline), IV Hydrocortisone 100mg stat, then q6-8h.
• Maternal/Fetal Effects (Poor Control): Maternal crisis, IUGR, preterm labor.

⭐ Women with known adrenal insufficiency require parenteral stress doses of corticosteroids (e.g., hydrocortisone 100mg IM/IV every 6-8 hours) throughout labor and delivery, and in the immediate postpartum period.

Pheochromocytoma in Pregnancy - Adrenaline Attack

• Rare catecholamine-secreting tumor. "Rule of 10s" (e.g., 10% malignant) less typical in pregnancy.
• Clinical Presentation:
  • Classic Triad: Paroxysmal Hypertension, Palpitations, Headaches.
  • Diaphoresis is also key.
  • 📌 P.H.E.O. Mnemonic: Palpitations, Headache, Episodic sweating, Others (anxiety/tremor).
• Diagnosis:

  Test Type	Method
  Biochemical	24hr urinary fractionated metanephrines & catecholamines; Plasma free metanephrines
  Localization	MRI (preferred over CT)

• Management:

• Maternal/Fetal Risks: Extremely high if undiagnosed (↑↑ mortality).

⭐ Undiagnosed pheochromocytoma in pregnancy can lead to maternal and fetal mortality rates as high as 50%; thus, prompt diagnosis and management with alpha-adrenergic blockade are crucial.

High-Yield Points - ⚡ Biggest Takeaways

• Physiological hypercortisolism can mask Cushing's syndrome in pregnancy.
• Cushing's syndrome: ↑maternal/fetal risks (preeclampsia, GDM, IUGR); surgery (2nd tri) or metyrapone.
• Addison's disease: ↑steroid dose in labor/stress; continue fludrocortisone.
• CAH: Dexamethasone to mother for at-risk female fetus (virilization).
• Pheochromocytoma: Alpha-blockade (e.g., phenoxybenzamine) then beta-blockade; surgery pre-16 weeks/postpartum.
• Primary aldosteronism: Often improves; spironolactone contraindicated; use amiloride/nifedipine for severe HTN_