para>Complete loss of pituitary function is life-threatening and requires immediate treatment. Head CT or MRI can help evaluate pituitary lesion due to mass, infarct, or hemorrhage, but imaging is rarely needed in a setting of classic clinical picture: An empty sella may be seen on imaging if pituitary necrosis has occurred, particularly if condition has been prolonged (2,3).
Pregnancy Considerations
The pituitary gland enlarges in size during pregnancy, up to 136% of the average nonpregnant size, making it more dependent on blood flow and susceptible to ischemia (5).
- Pituitary hormones should be tested individually. Earliest lost hormones are PRL and GH (5). Serum studies should be drawn in the morning when diurnal cortisol level is maximum (6):
- May show decrease in serum cortisol, free (T4), and estradiol
- LH and FSH should only be tested if patient is amenorrheic. Measured LH and FSH are usually low but may be normal.
- PRL level is usually low.
- TSH levels may be normal, low, or paradoxically elevated but biologically less active (2).
- GH levels are typically low.
- Majority of patients have ACTH deficiency.
- CBC may show normocytic and normochromic anemia or pancytopenia (7).
- Hyponatremia is the most common electrolyte disturbance, occurring in 33 " 69% of cases (7).
- Serum glucose may be consistent with hypoglycemia.
- If the pituitary stalk is affected, the patient may have central diabetes insipidus (decreased or no ADH) and hypernatremia (2).
Test Interpretation
- Necrosis of anterior pituitary gland
- Chronic findings may show replacement of necrotic anterior pituitary gland with hypocellular connective tissue (1).
TREATMENT
MEDICATION
First Line
- Hypocortisolism: Hydrocortisone is replaced first to avoid adrenal crisis from replacing T4 alone.
- Hydrocortisone: 15 to 25 mg/day (standard adult dose)
- Treatment is generally 2 to 3 doses daily (6), but recent studies suggest that 5 mg BID is adequate and prevents overreplacement.
- Monitoring is mostly clinical due to lack of objective parameters (6)[C].
Pregnancy Considerations
Cortisol-binding globulin and free cortisol levels increase during pregnancy.
Increase hydrocortisone replacement by 50% in the 3rd trimester.
Administer peripartum stress dose of hydrocortisone (6)[C].
Second Line
- Replace hormones based on individual deficiencies.
- Hypothyroidism: T4 replacement titrated to individual requirement per serum studies. Levothyroxine replacement should be followed by serum free T4 concentration with goal of normal serum free T4 level of 1.5 ¼g/kg body weight (6)[C].
Pregnancy Considerations
Thyroid-binding hormone levels increase during pregnancy.
Replacement of thyroid hormone should be increased by 30%.
Hypogonadism: gonadotropin replacement titrated to individual requirements per serum studies or clinical symptoms. In women with hypogonadism
Replace estrogen and progesterone to mimic physiologic secretion in women with uteri and estrogen only if no uterus is present
Treat premenopausal women with an oral contraceptives containing 20 to 35 ¼g of estrogen.
May consider treatment with transdermal estradiol (6)
If fertility is desired, treat with pulsatile GnRH and refer to a reproductive endocrinologist (6).
GH deficiency: Patients with severe GH deficiency may undergo replacement.
GH replacement is controversial in adults.
No standard recommendations exist.
If replacement is desired, low-dose therapy beginning at 0.15 to 0.3 mg/day, with monitoring and titration adjusted at an individual level, as response varies widely, based on IGF-I levels and following body measurements and composition (6)
PRL deficiency: Currently, there is no treatment available for PRL deficiency. As lactation is not feasible, infants will require bottlefeeding.
ISSUES FOR REFERRAL
- In general, consider an endocrinology referral.
- For infertility, consider a reproductive endocrinology referral.
INPATIENT CONSIDERATIONS
Admission Criteria/Initial Stabilization
- Patient should be admitted if in shock, adrenal crisis, or based on clinical judgment.
- Once stabilized with first-line treatment, hormone replacement may be started and monitored in an outpatient setting.
- See "First Line. "
- For patients in shock, use ACLS guidelines.
IV Fluids
Patients may be in shock secondary to postpartum hemorrhage. Replace IV fluids per ACLS guidelines.
ONGOING CARE
FOLLOW-UP RECOMMENDATIONS
Patient Monitoring
See "Treatment. " Follow individual hormone replacement levels per standard recommendations.
PATIENT EDUCATION
American College of Obstetricians and Gynecologists, 409 12th St. SW, Washington, DC 20024-2188 (800) 762-ACOG; http://www.acog.org
PROGNOSIS
Rarely fatal but requires lifelong hormone replacement
COMPLICATIONS
May be fatal without glucocorticoid or thyroid hormone replacement
REFERENCES
11 Kovacs K. Sheehan syndrome. Lancet. 2003;361(9356):520 " 522.22 Tessnow AH, Wilson JD. The changing face of Sheehan 's syndrome. Am J Med Sci. 2010;340(5):402 " 406.33 Matsuwaki T, Khan KH, Inoue T, et al. Evaluation of obstetrical factors related to Sheehan Syndrome. J Obstet Gynaecol Res. 2014;40(1):46 " 52.44 Schrager S, Sabo L. Sheehan syndrome: a rare complication of postpartum hemorrhage. J Am Board Fam Pract. 2001;14(5):389 " 391.55 Kilicli F, Dokmetas HS, Acibucu F. Sheehan 's syndrome. Gynecol Endocrinol. 2013;29(4):292 " 295.66 van Aken MO, Lamberts SWJ. Diagnosis and treatment of hypopituitarism: an update. Pituitary. 2006;8(3 " 4):183 " 191.77 Shivaprasad C. Sheehan 's syndrome: newer advances. Indian J Endocrinol Metab. 2011;15(Suppl 3):S203 " S207.
ADDITIONAL READING
- Mousa HA, Blum J, Abou El Senoun G, et al. Treatment for primary postpartum haemorrhage. Cochrane Database Syst Rev. 2014;(2):CD003249.
SEE ALSO
Hypopituitarism
CODES
ICD10
E23.0 Hypopituitarism
ICD9
253.2 Panhypopituitarism
SNOMED
Sheehans syndrome (disorder)
CLINICAL PEARLS
- Sheehan syndrome is a rare disorder of postpartum panhypopituitarism due to ischemia and subsequent necrosis of the pituitary gland classically secondary to severe postpartum hemorrhage.
- Symptoms vary widely and are secondary to individual hormone deficiencies. Patients may initially be asymptomatic, and diagnosis may be delayed for years.
- During times of stress or illness, undiagnosed or undertreated patients are at risk for adrenal crisis.
- Lifelong individualized hormone replacement therapy is essential for the prognosis of these patients.