Endocrine · Year 2 · from Endocrine
Case 2: Sheehan Syndrome (Postpartum Pituitary Necrosis)
Patient Demographics
- Age: 34 years
- Sex: Female
- Occupation: Elementary school teacher
Chief Complaint
"I've been exhausted since my delivery 6 weeks ago and I can't produce any breast milk."
History of Present Illness
A 34-year-old woman, G2P2, presents 6 weeks postpartum with profound fatigue, inability to lactate, and ongoing amenorrhea. Her delivery was complicated by postpartum hemorrhage requiring blood transfusion after retained placenta. She lost approximately 2 liters of blood and had a period of hypotension (BP 70/40 mmHg) for about 45 minutes before stabilization. Since delivery, she has been unable to breastfeed despite multiple attempts and lactation consultation. She reports feeling cold, constipated, and has noticed hair loss.
Physical Examination
- Vital Signs: BP 92/60 mmHg (orthostatic drop), HR 54 bpm, Temp 35.8°C
- General: Pale, lethargic appearing, dry skin
- Breasts: No engorgement, no galactorrhea with expression
- Thyroid: Normal size, non-tender
- Neurologic: Delayed relaxation of ankle reflexes
Workup
- Laboratory Studies:
- Sodium: 128 mEq/L (low)
- TSH: 1.2 mIU/L (inappropriately normal)
- Free T4: 0.5 ng/dL (low)
- Prolactin: 2 ng/mL (very low, expected postpartum elevation)
- Cortisol (AM): 2.8 μg/dL (low)
- ACTH: 8 pg/mL (inappropriately normal/low)
- FSH/LH: Low
- MRI Pituitary: Empty sella or partially empty sella with pituitary tissue flattened against sellar floor
Diagnosis
Sheehan syndrome (postpartum pituitary necrosis) with panhypopituitarism
Treatment
- Emergency glucocorticoid replacement (hydrocortisone)
- Levothyroxine (started after cortisol replacement is established)
- Consider estrogen/progesterone for bone protection
- Long-term monitoring of all pituitary axes
- Education about stress dosing of glucocorticoids
Clinical Pearl
Sheehan syndrome occurs due to ischemic necrosis of the enlarged, hyperemic pituitary gland of pregnancy when there is significant postpartum hemorrhage and hypotension. The pituitary approximately doubles in size during pregnancy due to lactotroph hyperplasia, making it vulnerable to hypoperfusion. The classic triad is failure to lactate, amenorrhea, and features of hypopituitarism. The inability to lactate is often the first recognized sign, as prolactin deficiency prevents milk production.
Clinical Image
Sagittal T1-weighted MRI showing an empty sella with CSF filling the sella turcica and flattened pituitary tissue.
Image Source: Radiopaedia - "Empty sella syndrome" License: CC BY-NC-SA 3.0 URL: https://radiopaedia.org/cases/empty-sella-syndrome