Endocrine

Pituitary apoplexy: recognition and emergency management

Clinical Overview and When to Suspect Pituitary Apoplexy

— Occurs in ~2–12% of pituitary adenomas; nonfunctioning macroadenomas most common substrate

— Peak age 50s–60s; slight male predominance

— Up to 80% of patients have no prior diagnosis of pituitary tumor at presentation

— Hypertension, major surgery (especially cardiac bypass)

— Anticoagulation (warfarin, DOACs, heparin)

— Dynamic pituitary testing (TRH, GnRH, insulin tolerance test)

— Dopamine agonist initiation or withdrawal

— Head trauma, pregnancy, postpartum hemorrhage (Sheehan syndrome is the postpartum ischemic variant)

— Estrogen therapy, GnRH agonists

— Acute ACTH deficiency → adrenal crisis with refractory hypotension and death

— Expanding sellar mass compresses optic chiasm (permanent blindness within hours) and cavernous sinus contents (CN III, IV, V1/V2, VI)

— Can mimic subarachnoid hemorrhage, bacterial meningitis, or stroke — anchoring on those diagnoses delays steroids

Board pearl: Any patient with a thunderclap headache and a non-bleeding head CT who then develops hypotension unresponsive to fluids — think pituitary apoplexy and give hydrocortisone before the MRI tech arrives.

Definition: Acute hemorrhage and/or infarction of the pituitary gland, almost always within a pre-existing (often unrecognized) pituitary adenoma. A neuroendocrine emergency combining sudden mass effect with acute hypopituitarism.

Epidemiology:

Precipitants to recall on the exam:

When to suspect (the classic trigger phrase): Sudden severe (often retro-orbital or bifrontal) "thunderclap" headache + visual disturbance + ophthalmoplegia ± altered mental status ± hemodynamic instability.

Why it is a true emergency:

Step 3 management mindset: The decision that saves the patient is empiric stress-dose hydrocortisone before imaging confirmation whenever apoplexy is on the differential and the patient is hypotensive, hyponatremic, or obtunded — never wait for cortisol results.

Presentation Patterns and Key History

— Sudden severe headache (>95% of cases): retro-orbital, bifrontal, or generalized; often described as "worst headache of life" — overlaps with SAH stem language

— Visual field defect: classic bitemporal hemianopia from upward chiasmal compression; can also be monocular blindness if optic nerve compressed

— Ophthalmoplegia: CN III palsy most common (ptosis, "down-and-out" eye, mydriasis); CN VI and IV next; cavernous sinus syndrome if multiple

— Altered mental status: lethargy → stupor → coma, often from hyponatremia, hypocortisolism, or meningismus from blood in CSF

— Onset over minutes to hours; symptoms may evolve over 1–3 days

— Subacute or "silent" apoplexy exists — picked up later as empty sella with new hypopituitarism

— Known pituitary adenoma, prolactinoma, acromegaly, Cushing disease

— Recent anticoagulation, antiplatelet, thrombolytic

— Recent surgery (cardiac, orthopedic), childbirth with hemorrhage, head trauma

— Symptoms of chronic hypopituitarism preceding the event: amenorrhea, decreased libido, fatigue, cold intolerance, weight changes

— Polyuria/polydipsia (diabetes insipidus is uncommon acutely but possible)

— Postpartum patient with failure to lactate + hypotension + hypoglycemia → Sheehan syndrome

— Pregnant patient with new headache + vision change → pituitary enlargement (physiologic) predisposes to apoplexy

Key distinction: SAH headache + CN III palsy points to posterior communicating artery aneurysm; pituitary apoplexy headache + CN III palsy + bitemporal field cut + hyponatremia points to the sella. Both can coexist with neck stiffness — the sella lesion is found only if you look at the pituitary on MRI, not just CTA circle of Willis.

Cardinal symptom tetrad (rarely all four together; presence of any two should prompt workup):

Tempo:

History to extract quickly in the ED:

Pediatric and pregnancy clues:

Meningismus mimicry: Blood and necrotic tissue tracking into the subarachnoid space cause neck stiffness, photophobia, and fever, leading to misdiagnosis as bacterial meningitis or SAH.

Physical Exam Findings and Hemodynamic Assessment

— Hypotension out of proportion to volume status, often refractory to crystalloid (acute secondary adrenal insufficiency)

— Hyponatremia-driven confusion, seizures (Na often 120s)

— Hypoglycemia from cortisol and GH deficiency

— Hypothermia from central hypothyroidism (subacute)

— Tachycardia may be blunted if concomitant central hypothyroidism

— Visual acuity each eye separately — can drop from 20/20 to no light perception in hours

— Confrontation visual fields: bitemporal hemianopia or superior bitemporal quadrantanopia

— Pupils: a fixed dilated pupil = CN III compression, not herniation if otherwise alert

— Extraocular movements: ptosis + eye deviated down-and-out = CN III; isolated lateral rectus weakness = CN VI (most vulnerable in cavernous sinus)

— Fundoscopy: optic disc usually normal acutely (papilledema takes time); look for pallor suggesting chronic compression

— Skin: hyperpigmentation argues against secondary adrenal insufficiency (ACTH low, so MSH-driven pigment absent) — useful Step 3 discriminator from primary Addison

— Look for stigmata of acromegaly (coarse features, large hands) or Cushing (moon facies, striae) suggesting the underlying adenoma type

— MAP goal ≥65; if not achieved after 1–2 L isotonic fluid, escalate to norepinephrine and give hydrocortisone 100 mg IV immediately

— Place arterial line if pressors needed; central access for vasopressor delivery and CVP trending

CCS pearl: In the CCS case, order "hydrocortisone 100 mg IV bolus, then 50 mg IV q6h" the same minute you order the MRI. Then add "neurosurgery consult," "ophthalmology consult," and "ICU admission." Skipping the steroid before imaging is the most common reason cases fail.

Vital signs — the apoplexy fingerprint:

Neuro-ophthalmologic exam (do this before steroids if patient stable, but do not delay treatment):

Cranial nerve V1/V2: facial numbness over forehead or maxilla from cavernous sinus involvement

Meningeal signs: Kernig, Brudzinski may be positive — do not anchor on meningitis

General:

Hemodynamic assessment workflow:

Diagnostic Workup — Initial Labs, Imaging, ECG, Biomarkers

— Random cortisol and ACTH — single most important endocrine lab; cortisol <5 µg/dL in acutely ill patient confirms insufficiency

— TSH, free T4 (central pattern: low/normal TSH with low free T4)

— Prolactin (often low in apoplexy due to stalk destruction; high if prolactinoma was the substrate)

— LH, FSH, total testosterone (men), estradiol (women)

— IGF-1 (for GH axis)

— CMP: hyponatremia (SIADH-like from hypocortisolism, or DI later); hypoglycemia

— CBC, coagulation panel (PT/INR, aPTT) — check for anticoagulant effect

— Type and screen (preop)

— Serum and urine osmolality + urine sodium if Na abnormal

— Non-contrast head CT first in the ED: rules out SAH, large ICH; may show hyperdensity in sella in ~25% of acute hemorrhage cases. A normal CT does NOT exclude apoplexy.

— MRI pituitary with and without gadolinium = gold standard: sellar mass with heterogeneous signal, fluid–fluid levels, peripheral enhancement, suprasellar extension, chiasmal compression. T1 hyperintensity = subacute blood; T2 variable.

— If MRI contraindicated: dedicated thin-cut CT of sella with contrast

Board pearl: A patient with thunderclap headache, negative non-contrast CT, and then an LP showing xanthochromia is the SAH stem; the same patient with hyponatremia, hypotension, and a CN III palsy needs an MRI of the pituitary, not a CTA — order both if uncertain.

Immediate labs (draw before steroids if possible, but never delay treatment >5 minutes for the draw):

Imaging — the diagnostic backbone:

ECG: baseline — look for hypothyroid bradycardia, low voltage, prolonged QT (from hypothyroidism/hyponatremia); screen before pressors

CXR: if hypotensive or considering sepsis/PE in differential

LP — generally avoid unless MRI excludes the diagnosis and meningitis remains a serious concern; xanthochromia and elevated protein can occur from apoplexy alone

Diagnostic Workup — Advanced and Confirmatory Studies

— Dedicated sellar protocol: thin-slice (2–3 mm) sagittal and coronal T1 pre- and post-gadolinium, T2, and ideally susceptibility-weighted imaging (SWI) for blood

— Findings: enlarged sella with heterogeneous mass; ring enhancement around necrotic core; thickened/deviated infundibulum; suprasellar extension elevating optic chiasm; cavernous sinus invasion

— Hemorrhagic signal evolves: hyperacute (oxyHgb) iso-T1/bright-T2; acute (deoxyHgb) iso-T1/dark-T2; subacute (metHgb) bright-T1 — most apoplexy MRIs are caught in the subacute "bright T1" window

— Humphrey visual field testing once stable — documents baseline and tracks recovery

— Optical coherence tomography (OCT) of retinal nerve fiber layer for prognostication

— ACTH stimulation test is unreliable acutely (adrenals not yet atrophied)

— Defer formal axis testing 4–6 weeks post-event; in the interim, treat empirically and recheck morning cortisol/free T4 weekly

— Components: level of consciousness (GCS), visual acuity, visual fields, ocular paresis — higher score → stronger surgical indication

— Coagulation correction (reverse warfarin with 4-factor PCC + vitamin K; hold DOAC, give andexanet/idarucizumab as appropriate)

— Cardiac risk assessment if elderly

— Anesthesia consult — difficult airway if acromegalic features

Step 3 management: Don't order a cosyntropin stimulation test in the ED for suspected apoplexy. Treat empirically with hydrocortisone, send the random cortisol and ACTH before the dose, and let endocrinology repeat dynamic testing weeks later. Acute test results will mislead because the adrenal glands respond normally for days after pituitary failure.

MRI protocol specifics (know for the exam):

CT angiography or MRA: consider when SAH still possible or to map vascular anatomy preoperatively; rules out PCom aneurysm causing isolated CN III palsy

Formal neuro-ophthalmology assessment:

Dynamic endocrine testing — NOT in the acute phase:

Pituitary Apoplexy Score (UK guideline, useful for surgical decision):

Pre-op evaluation if surgery planned:

Risk Stratification and First-Line Management Logic

— A/B/C: airway protection if GCS ≤8; supplemental O₂; IV access ×2 large bore

— Fluids: isotonic saline; if hyponatremic and symptomatic, judicious 3% saline (correct ≤8 mEq/L per 24 h)

— Empiric hydrocortisone: 100 mg IV bolus, then 50 mg IV q6h (or 200 mg/24h continuous infusion). Dexamethasone 4 mg IV is an acceptable alternative when steroid would interfere with diagnostic imaging interpretation elsewhere — but hydrocortisone is preferred because it provides both glucocorticoid and mineralocorticoid activity at stress doses.

— MRI pituitary with contrast

— Neurosurgery and endocrinology consults simultaneously

— Ophthalmology consult for formal visual assessment

— Conservative management appropriate when: alert, mild/no visual deficit, no significant ophthalmoplegia, stable. Continue steroids, serial neuro exams q1–2h, repeat MRI in 7 days.

— Urgent transsphenoidal surgery (within 7 days, often <72h) indicated for: deteriorating consciousness, severe or worsening visual acuity loss, worsening visual field defect, progressive ophthalmoplegia. Earlier surgery (<72h) correlates with better visual recovery.

— Acute cortisol deficiency → impaired free water excretion → euvolemic hyponatremia mimicking SIADH; this resolves with hydrocortisone, not fluid restriction

— Avoid hypertonic saline unless seizing or severely symptomatic

— Hold and reverse immediately

— Bridge decisions (e.g., mechanical valve) made jointly with cardiology and neurosurgery

CCS pearl: The "advance clock" trap in CCS is ordering MRI first and forgetting the steroid. Order hydrocortisone IV stat, then advance the clock 15 minutes for the MRI. The grading engine credits the steroid before imaging.

The "ABC-Steroid-MRI-Neurosurgery" sequence — memorize this order for CCS:

Conservative vs surgical pathway — risk stratification:

Hyponatremia management nuance:

Anticoagulation:

Pharmacotherapy — First-Line Drug Regimen

— Hydrocortisone 100 mg IV bolus, then 50 mg IV q6h for 24–72 h, then taper

— Alternative: hydrocortisone 200 mg/24h continuous infusion

— Methylprednisolone 40 mg IV q6h or dexamethasone 4 mg IV q6h acceptable substitutes; dexamethasone preferred only if anti-edema effect prioritized and cortisol assays still pending elsewhere

— Taper to physiologic replacement (hydrocortisone 15–25 mg/day divided, e.g., 10–15 mg AM + 5–10 mg early afternoon) once stable, typically over 5–7 days

— Always start glucocorticoids first — giving levothyroxine before cortisol can precipitate adrenal crisis by increasing cortisol clearance

— Start levothyroxine 1.6 µg/kg/day PO once cortisol replaced and patient stable (usually 24–48 h in); lower starting dose (25–50 µg) in elderly/cardiac patients

— Goal free T4 in upper half of reference range; TSH is unreliable in central hypothyroidism

— Indicated only if polyuria + hypernatremia + dilute urine emerge (more common post-op than at presentation)

— Start 1 µg SC/IV or 10 µg intranasal; titrate to urine output and serum sodium

— Analgesia: acetaminophen ± low-dose opioid; avoid NSAIDs (bleeding risk)

— Antiemetics: ondansetron (monitor QT)

— DVT prophylaxis: mechanical initially; chemical once surgical plan and bleeding stable

— Stress ulcer prophylaxis with PPI while on high-dose steroids and critically ill

— Bromocriptine/cabergoline acutely (no evidence to shrink hemorrhagic adenoma fast enough)

— Mannitol unless clear herniation

— Empiric antibiotics unless meningitis cannot be excluded — then ceftriaxone + vancomycin + ampicillin + dexamethasone pending LP

Board pearl: Cortisol before thyroid — every time. The classic distractor is "start levothyroxine and admit"; the right answer is "hydrocortisone IV, then levothyroxine after cortisol replacement."

Glucocorticoid replacement (cornerstone):

Thyroid hormone replacement:

Sex hormone replacement: deferred to outpatient endocrine follow-up

Growth hormone replacement: deferred; assessed months later

Desmopressin (DDAVP) for central DI:

Symptomatic care:

Avoid:

Procedures — Transsphenoidal Decompression and Invasive Management

— Endoscopic endonasal transsphenoidal decompression is preferred

— Timing: within 7 days for visual deficits; ideally <72 h for severe or progressive deficits; emergent (<24 h) for rapidly deteriorating vision or consciousness

— Indications (recap): severe/worsening visual acuity loss, worsening field defect, declining mental status, progressive ophthalmoplegia, large mass with chiasmal compression

— Goals: decompress optic apparatus, evacuate hematoma/necrotic tissue, obtain histopathology

— Visual recovery: ~80% improve if operated within first week; ophthalmoplegia recovers in >90% (often spontaneously even without surgery)

— Endocrine recovery is less predictable — most patients still need lifelong replacement of at least one axis

— Continue stress-dose hydrocortisone through surgery and taper postoperatively

— Monitor urine output q1h, serum Na q6h for triphasic response: transient DI (days 1–3) → SIADH (days 4–10) → permanent DI in subset

— Watch for CSF leak (clear rhinorrhea, β2-transferrin positive), meningitis, sinusitis

— Q1–2 h neuro and visual checks for 48 h

— Repeat MRI at 7 days, 6 weeks, then per stability

— Outpatient endocrine reassessment at 4–6 weeks

— ICU x 24 h minimum

— Step-down with strict I&O, sodium trending, and visual field rechecks

— Average length of stay 4–7 days uncomplicated

Step 3 management: Post-TSS polyuria with rising Na and dilute urine = central DI → give DDAVP. Polyuria with falling Na = appropriate diuresis, not DI — don't reflexively give DDAVP because urine output is high.

Transsphenoidal surgery (TSS) — standard operative approach:

Outcomes:

Perioperative management:

Craniotomy: reserved for large suprasellar extension not accessible transsphenoidally

Endovascular procedures: not used for apoplexy itself; only if a coexisting PCom aneurysm is found

Conservative pathway specifics:

Post-op disposition:

Special Populations — Elderly and Renal/Hepatic Impairment

— Higher prevalence of unrecognized macroadenomas; apoplexy may be the first presentation

— Presentation often atypical: confusion or "failure to thrive" instead of thunderclap headache; visual symptoms underreported due to baseline impairment

— Comorbid HTN, anticoagulation for AFib, and antiplatelets are common precipitants

— Levothyroxine initiation: start 25 µg/day and titrate by 12.5–25 µg q4–6 weeks; check for angina or AFib

— Surgical risk higher — but TSS is generally well tolerated even into the 80s when indicated

— Postoperative delirium common; minimize benzodiazepines and anticholinergics

— Hydrocortisone dosing unchanged (hepatic metabolism)

— Caution with iodinated contrast for CTA — prefer non-contrast CT + MRI; if contrast required, use isosmolar agent and IV hydration; gadolinium with eGFR <30 carries NSF risk — use macrocyclic agent (group II) if essential

— DDAVP dose may need reduction; monitor sodium closely (hyponatremia risk amplified)

— Hyponatremia correction even more cautious in CKD/dialysis patients

— Hydrocortisone metabolism reduced — start at standard stress dose but watch for hyperglycemia and edema

— Coagulopathy from liver disease may have contributed; correct with vitamin K, FFP, or 4-factor PCC before surgery

— Levothyroxine dosing unchanged

— Warfarin: 4-factor PCC 25–50 U/kg + vitamin K 10 mg IV

— Dabigatran: idarucizumab 5 g IV

— Factor Xa inhibitors (apixaban, rivaroxaban): andexanet alfa or 4-factor PCC if andexanet unavailable

— Heparin: protamine sulfate

— Antiplatelets: platelet transfusion controversial; desmopressin 0.3 µg/kg may help

Key distinction: In an elderly patient on warfarin with sudden headache + vision change, the answer is rarely "CT head and discharge if negative" — it is reverse anticoagulation, MRI pituitary, and admit. Missing apoplexy on a negative non-contrast CT is a classic geriatric pitfall.

Elderly patients:

Chronic kidney disease:

Hepatic impairment:

Anticoagulated patients:

Special Populations — Pregnancy, Postpartum, and Pediatrics

— The pituitary doubles in size (lactotroph hyperplasia) — increased vulnerability

— Pre-existing adenoma + pregnancy is the highest-risk combination

— Symptoms identical: headache, vision change, CN palsies

— MRI without gadolinium preferred; gadolinium relatively contraindicated (especially first trimester) — usually non-contrast MRI is diagnostic

— Hydrocortisone safe in pregnancy (does not cross placenta significantly because of placental 11β-HSD2)

— Surgery, if needed, is safe in second trimester; balance maternal vision vs fetal risk

— Coordinate with MFM and neuroanesthesia

— Pathogenesis: peripartum hemorrhage → hypotension → ischemic necrosis of the enlarged gland

— Acute presentation: failure to lactate, persistent hypotension, hypoglycemia, hyponatremia in the days after delivery

— Chronic presentation: months–years later with amenorrhea, fatigue, loss of axillary/pubic hair, cold intolerance

— Treatment: same — hydrocortisone first, then levothyroxine; sex steroid replacement; usually no surgery needed

— Diagnosis: MRI shows empty sella over time

— Autoimmune; presents with headache, vision change, hypopituitarism

— MRI: symmetric pituitary enlargement with stalk thickening, homogeneous enhancement (vs heterogeneous in apoplexy)

— Treat with high-dose steroids; surgery only if mass effect refractory

— Rare; usually in setting of craniopharyngioma or known macroadenoma

— Growth failure, delayed puberty, or diabetes insipidus may precede

— Same management framework: stress-dose hydrocortisone (50–100 mg/m²), MRI, neurosurgery

— Long-term GH and pubertal hormone replacement coordinated with pediatric endocrinology

Board pearl: New mother + no lactation + hypotension + hyponatremia = Sheehan until proven otherwise. Don't anchor on postpartum depression or fluid loss; give hydrocortisone and check the pituitary axis.

Pregnancy:

Sheehan syndrome (postpartum pituitary necrosis):

Lymphocytic hypophysitis (peri/postpartum mimic):

Pediatric apoplexy:

Complications and Adverse Outcomes

— Adrenal crisis: refractory hypotension, hypoglycemia, hyponatremia, death if steroids delayed

— Permanent visual loss: correlates directly with time-to-decompression when severe at presentation

— Cerebral herniation: rare but possible with massive suprasellar extension

— Stroke: vasospasm from subarachnoid blood; internal carotid compression in cavernous sinus

— Meningitis-like aseptic inflammation: from blood and necrotic tissue in CSF

— Cardiovascular collapse from combined cortisol and thyroid deficiency

— Diabetes insipidus (more often post-op than spontaneous)

— SIADH in triphasic response post-op

— CSF leak post-transsphenoidal surgery — risk of meningitis

— Sinusitis, epistaxis post-TSS

— Hypoglycemia from GH and cortisol deficiency

— Panhypopituitarism in 60–80% of patients regardless of surgical vs conservative approach

— Lifelong hormone replacement (cortisol, thyroid, sex hormones, possibly GH and DDAVP)

— Infertility without gonadotropin replacement or assisted reproduction

— Osteoporosis from sex hormone and GH deficiency

— Increased cardiovascular mortality from untreated/undertreated hypopituitarism

— Recurrent tumor growth or re-bleed in patients managed conservatively

— Cognitive and quality-of-life impairment

— Osmotic demyelination from rapid Na correction

— Hyperglycemia and infection from prolonged high-dose steroids

— Levothyroxine-induced cardiac ischemia if started too aggressively

— DDAVP overdose → severe hyponatremia and seizures

Step 3 management: Any patient discharged after apoplexy needs a written "sick day rules" card: double or triple the hydrocortisone dose for fever, illness, surgery, or trauma; injectable hydrocortisone 100 mg IM at home for vomiting; medical alert bracelet mandatory.

Acute (hours to days):

Subacute (days to weeks):

Long-term:

Iatrogenic complications to watch:

When to Escalate Care — ICU, Consult, and Inpatient Triage

— Hemodynamic instability requiring pressors

— GCS ≤12 or fluctuating mental status

— Severe hyponatremia (<125) or rapid correction in progress

— Need for hourly neuro and visual checks

— Post-transsphenoidal surgery (first 24 h minimum)

— Severe ophthalmoplegia or progressive visual loss

— Hemodynamically stable on oral hydrocortisone

— Stable visual exam over 24 h

— Sodium ≥130 and trending normal

— No evidence of evolving DI or SIADH

— Neurosurgery — operative decision

— Endocrinology — hormone replacement and outpatient follow-up

— Ophthalmology / neuro-ophthalmology — formal acuity, fields, photography

— ICU/critical care — admission

— Anesthesiology — preoperative airway and hemodynamic planning

— Consider neuro-IR if vascular anomaly suspected

— Community hospital without neurosurgery or pituitary expertise → transfer to tertiary center after initial stabilization and steroid administration

— Do not delay hydrocortisone or fluids waiting for transfer

— Use closed-loop communication and accept verbal handoff with documented vitals, exam, meds given, and imaging on disk

— Stable on oral steroid and thyroid replacement ≥48 h

— Stable Na, glucose, urine output

— Documented stable or improving visual exam

— Endocrine and neurosurgery follow-up arranged within 1–2 weeks

— Patient and family trained in sick day rules and DDAVP if applicable

CCS pearl: In any pituitary apoplexy CCS scenario, the location move should be "Emergency Department → ICU" after the initial orders. Failing to upgrade location loses points even when all clinical orders are correct.

ICU admission criteria (essentially all apoplexy patients initially):

Floor/step-down acceptable when:

Consults to place immediately (in CCS, order all in parallel):

Transfer criteria:

Discharge criteria:

Key Differentials — Same-Category (Sellar/Parasellar) Causes

— Benign cystic remnant; can hemorrhage causing apoplexy-like syndrome

— MRI: intracystic nodule, often without significant enhancement

— Treated similarly with TSS if symptomatic

— More common in children and 50–60s

— Calcifications on CT, often suprasellar; mixed solid-cystic

— Hypopituitarism, DI more common than in adenoma

— Autoimmune, peri/postpartum or with checkpoint inhibitor therapy (ipilimumab, nivolumab)

— Symmetric enlargement, thickened stalk, homogeneous enhancement

— Responds to high-dose glucocorticoids; surgery rarely needed

— Step 3 cue: cancer patient on immunotherapy with new headache and fatigue

— Rare; fever, leukocytosis; ring-enhancing sellar mass with restricted diffusion on DWI

— Needs surgical drainage + antibiotics

— Usually incidental; can produce mild hypopituitarism

— Not acute, but the chronic sequela of subclinical apoplexy or Sheehan

— Dural-based, homogeneous enhancement, dural tail

— Generally subacute/chronic visual loss

— Breast and lung most common

— DI more frequent than with adenoma (posterior pituitary involvement)

— Rapid growth can mimic apoplexy

— Mucormycosis in diabetic or immunocompromised; consider in DKA patient with vision change

— Black eschar on nasal exam; surgical debridement + amphotericin B emergently

Key distinction: Apoplexy MRI shows a heterogeneous, often hemorrhagic sellar mass with peripheral enhancement; hypophysitis shows a homogeneously enhancing, symmetrically enlarged gland with a thickened stalk — the latter responds to steroids alone.

Rathke cleft cyst hemorrhage:

Craniopharyngioma with cystic hemorrhage:

Lymphocytic hypophysitis:

Pituitary abscess:

Empty sella syndrome:

Meningioma (sellar/parasellar):

Metastasis to pituitary:

Sphenoid sinus mucocele or invasive fungal sinusitis:

Key Differentials — Other-Category Causes

— Same thunderclap headache; CT positive in >95% within 6 h; LP with xanthochromia confirms

— CTA shows aneurysm; PCom aneurysm can cause CN III palsy mimicking apoplexy

— Fever, neck stiffness, photophobia overlap; LP shows neutrophilic pleocytosis, low glucose

— Apoplexy LP shows blood/xanthochromia, elevated protein, normal glucose

— Recurrent, gradual onset, photophobia, history of similar episodes

— No CN deficits beyond transient aura

— Recurrent thunderclap headaches over days–weeks, often postpartum or with vasoactive drugs

— CTA/MRA shows "string of beads"

— Fever, proptosis, chemosis, painful ophthalmoplegia, often bilateral

— MR venography is diagnostic

— Treat with antibiotics + anticoagulation

— Painful ophthalmoplegia from idiopathic granulomatous inflammation of cavernous sinus

— Responds dramatically to steroids — but diagnosis of exclusion

— Cranial nerve findings + ataxia + crossed signs; MRI DWI diagnostic

— Neck pain, Horner syndrome, focal deficits; CTA neck diagnostic

— BP >180/120, vision changes, seizures; MRI shows posterior white matter edema

— Hyperpigmentation, hyperkalemia (vs normokalemia in secondary), elevated ACTH

— Same acute treatment but different long-term replacement (needs fludrocortisone)

Board pearl: The cleanest discriminator between primary and secondary (apoplexy) adrenal insufficiency is potassium and skin color: primary → hyperkalemia and hyperpigmentation; secondary → normal potassium and normal/pale skin.

Subarachnoid hemorrhage (SAH):

Bacterial meningitis:

Migraine with aura:

Reversible cerebral vasoconstriction syndrome (RCVS):

Cavernous sinus thrombosis:

Tolosa-Hunt syndrome:

Posterior circulation stroke:

Carotid or vertebral dissection:

Hypertensive emergency / PRES:

Adrenal crisis from primary adrenal insufficiency:

Secondary Prevention, Discharge Medications, and Long-Term Plan

— Hydrocortisone 15–20 mg PO every morning + 5–10 mg early afternoon (split dosing mimics circadian rhythm); alternative prednisone 3–5 mg daily or dexamethasone 0.25–0.5 mg daily (less preferred)

— Levothyroxine 1.6 µg/kg/day PO, adjusted to free T4

— Desmopressin PO 0.1–0.2 mg BID-TID or intranasal 10–20 µg BID, titrated to thirst and urine output, if DI present

— Sex steroid replacement initiated by endocrinology once stable: testosterone gel/IM in men (no contraindication); estrogen/progesterone in premenopausal women without contraindication

— Calcium 1000–1200 mg/day + vitamin D 800–1000 IU/day for steroid-associated bone loss

— Consider bisphosphonate if DXA shows osteoporosis or T-score <-1.5 on chronic steroids

— Minor illness/fever: double oral hydrocortisone for 2–3 days

— Vomiting or unable to tolerate PO: injectable hydrocortisone 100 mg IM at home, then ED

— Major surgery/trauma: 100 mg IV stress dose

— Always carry medical alert ID and emergency steroid kit

— MRI pituitary at 3 months, 12 months, then yearly × 5 years, then less frequently

— Visual field testing yearly

— Annual endocrine reassessment of all axes; GH stimulation testing once stable

— Statin if LDL elevated (panhypopituitarism raises CV risk)

— BP control with ACEi/ARB preferred

— Tobacco cessation

Step 3 management: The single most lifesaving outpatient intervention is the medical alert bracelet plus injectable hydrocortisone prescription. On the exam, "patient with prior pituitary surgery now vomiting with hypotension" → 100 mg IV hydrocortisone before any other order.

Discharge medications (typical regimen):

Sick day rules (must be documented and taught before discharge):

Long-term surveillance for tumor recurrence:

Cardiovascular risk modification:

Vaccinations: influenza yearly, pneumococcal series, COVID boosters — immunocompetent but at higher risk of decompensation from infection

Follow-Up, Monitoring Parameters, and Rehab/Counseling

— Endocrinology: 1–2 weeks post-discharge, then 4–6 weeks (formal axis re-testing), then 3 months, then every 6 months

— Neurosurgery: 2 weeks (wound check), 3 months (post-op MRI), then yearly

— Ophthalmology: 2 weeks, 3 months, then yearly with formal fields

— Primary care: 1–2 weeks for medication reconciliation, BP, glucose

— Morning cortisol on hold day (skip morning hydrocortisone) at 4–6 weeks to determine if HPA axis recovered; do NOT do this acutely

— Free T4 (not TSH) to titrate levothyroxine — goal mid-to-upper reference range

— Sodium and urine output if on DDAVP, weekly initially

— Testosterone, estradiol, LH/FSH at 4–6 weeks

— IGF-1 once stable; GH stimulation testing at endocrine discretion

— Fasting glucose and lipid panel

— DXA at baseline and every 2 years if on chronic steroid or with sex hormone deficiency

— Lifelong hormone replacement and never to stop steroids abruptly

— Sick day rules, injectable steroid use, medical ID

— Fertility planning — gonadotropin therapy can restore fertility in many patients

— Driving restriction until visual fields documented adequate (varies by state law)

— Return precautions: severe headache, vision change, polyuria, persistent vomiting, fever, confusion

— Vision rehab and low-vision services for residual deficits

— Occupational therapy for return to work; accommodations for visual field loss

— Psychological support — anxiety and depression common after acute neurologic events

— Pilots, commercial drivers: must be reported per FAA/DOT rules once visual or endocrine issues affect safety

CCS pearl: Order "outpatient endocrinology follow-up in 2 weeks" and "ophthalmology in 2 weeks" before ending the case. Missing follow-up orders is a common deduction even when acute management is perfect.

Follow-up cadence:

Monitoring labs:

Counseling topics:

Rehabilitation:

Driving and occupational implications:

Ethical, Legal, and Patient Safety Considerations

— Apoplexy patients often have altered consciousness; obtain consent for emergent transsphenoidal surgery from legally authorized surrogate (spouse, adult child) under your state's surrogate hierarchy

— If no surrogate available and surgery is life- or sight-saving, proceed under emergency exception to consent; document the threat to life/sight and absence of advance directive refusing care

— Two-physician documentation strengthens defense if challenged

— Hypocortisolism, hyponatremia, and hypoxia all impair capacity transiently; reassess after correction before accepting refusal of care

— Sudden vision loss may require notification to driving authorities per state law; counsel and document

— Medical errors (e.g., delayed steroid administration) fall under disclosure obligations; honest, prompt disclosure improves outcomes and reduces litigation

— Apoplexy is a "diagnostic error" hotspot — frequently misdiagnosed as migraine, meningitis, or SAH on first ED visit

— Build forcing functions: any "thunderclap headache + CN palsy" order set should include MRI pituitary protocol and hydrocortisone

— Sentinel event criteria may apply if delayed diagnosis caused permanent blindness — internal root cause analysis required

— Discharge without medical alert ID, sick day rules, or steroid prescription = malpractice risk

— Use teach-back: ask patient/family to state what they will do if vomiting at home

— Send structured discharge summary to PCP within 48 h

— Document indication for lifelong steroid; protect from inappropriate "taper off" by other clinicians who don't know the history

— Drug-drug interactions: rifampin, phenytoin, carbamazepine increase steroid clearance — may need dose increase

— Patients with metastatic cancer presenting with apoplexy from pituitary metastasis require goals-of-care discussion before transsphenoidal surgery — surgery may not be aligned with prognosis

Board pearl: A patient with apoplexy who refuses surgery while hypotensive and confused does not have capacity; treat under emergency exception and reassess once cortisol replaced.

Informed consent in the obtunded patient:

Capacity assessment:

Mandatory reporting and disclosure:

Patient safety system issues:

Transitions of care — the highest-risk moment:

Polypharmacy and steroid stewardship:

End-of-life considerations:

High-Yield Associations and Rapid-Fire Clinical Facts

Key distinction: "Worst headache of life + bitemporal hemianopia + CN III palsy + hyponatremia" beats "worst headache of life + neck stiffness + photophobia" as the apoplexy fingerprint — the field cut and electrolyte pattern are what differentiate it from SAH/meningitis.

Triggers (memorize): anticoagulation, hypertension, cardiac surgery (especially CABG with bypass), dynamic pituitary testing, dopamine agonists, pregnancy/postpartum, head trauma, estrogen.

Substrate: nonfunctioning macroadenoma > prolactinoma > GH-secreting > ACTH-secreting.

Sheehan syndrome: postpartum hemorrhage → ischemic pituitary necrosis → failure to lactate (earliest clue) → secondary amenorrhea, fatigue.

Hormone loss order (most to least vulnerable): GH → LH/FSH → TSH → ACTH → prolactin → ADH. ACTH loss is the most dangerous acutely.

Visual finding: bitemporal hemianopia from chiasmal compression.

Most common CN palsy: CN III (down-and-out, ptosis, dilated pupil).

Lab clues: hyponatremia (hypocortisolism, not SIADH primarily), hypoglycemia, low/normal TSH with low free T4, low cortisol.

Imaging: non-contrast CT often normal acutely; MRI pituitary with contrast is gold standard.

Treatment order: ABCs → fluids → hydrocortisone → MRI → neurosurgery → ophthalmology → ICU.

Drug not to give first: levothyroxine (gives before cortisol → adrenal crisis).

Surgery timing: within 7 days for visual symptoms; <72 h for severe/progressive deficits.

Triphasic post-op response: DI → SIADH → permanent DI.

Distinguishing primary vs secondary adrenal insufficiency: hyperkalemia and hyperpigmentation = primary; neither = secondary.

MRI pearl: subacute blood = bright on T1.

Hypophysitis vs apoplexy MRI: homogeneous symmetric enhancement vs heterogeneous hemorrhagic mass.

Mucormycosis in DKA with sinus pain + ophthalmoplegia is the differential to not miss — emergent amphotericin B and surgical debridement.

Checkpoint inhibitor hypophysitis: ipilimumab > nivolumab/pembrolizumab; treat with high-dose steroids.

Empty sella on MRI in a chronically hypopituitary patient = prior apoplexy or Sheehan.

Sick day rules: double oral dose for illness; IM 100 mg for vomiting; ED for major stress.

Medical alert ID + injectable hydrocortisone kit = lifesaving discharge bundle.

Board Question Stem Patterns

Step 3 management: When the stem says "negative non-contrast CT" but the patient is hyponatremic and hypotensive with vision change, never choose "discharge with outpatient follow-up." Always escalate: hydrocortisone, MRI pituitary, admit.

Classic ED stem: 55-year-old man on warfarin for AFib presents with sudden severe headache, blurred vision, and ptosis. BP 82/50, Na 128, glucose 58. CT head negative. Best next step? → IV hydrocortisone, then MRI pituitary. Distractors: dexamethasone alone (suboptimal), CTA only, lumbar puncture, levothyroxine.

Postpartum stem: Woman 5 days post-delivery (with PPH requiring transfusion) develops fatigue, inability to breastfeed, BP 88/54, Na 126, glucose 52. Diagnosis? → Sheehan syndrome. Next step? → hydrocortisone IV, then evaluate other axes.

Postoperative stem: Day 1 after CABG, patient develops thunderclap headache, fixed dilated pupil, hypotension despite fluids. → Pituitary apoplexy from bypass hemodynamics; hydrocortisone + MRI + neurosurgery.

Immunotherapy stem: Melanoma patient 8 weeks into ipilimumab develops headache, fatigue, low Na, low free T4 with low TSH. → Checkpoint inhibitor hypophysitis (apoplexy mimic); steroids and replacement.

Conservative vs surgical stem: Patient with apoplexy, normal vision, no ophthalmoplegia, GCS 15. Management? → Hydrocortisone, observation, serial exams, neurosurgery on standby, repeat MRI in 7 days. Surgery only if deterioration.

Cortisol-before-thyroid trap: "Which to start first?" → Always hydrocortisone before levothyroxine.

Post-op DI stem: Day 2 after TSS, urine output 400 mL/h, Na 152, urine osm 80. → Central DI; give DDAVP.

Triphasic stem: Day 6 post-TSS, urine output drops, Na falls to 128. → SIADH phase; fluid restrict, no DDAVP.

Discharge planning stem: "Most important discharge intervention?" → Medical alert ID + injectable hydrocortisone + sick day education.

Capacity stem: Hypotensive, confused apoplexy patient refuses surgery. → Lacks capacity; treat under emergency exception; obtain surrogate consent.

Differential stem: Thunderclap headache + CN III palsy + bitemporal hemianopia → apoplexy (not PCom aneurysm — that gives CN III without field cut).

Pediatric/young adult stem: Tall young man with acromegalic features develops sudden headache and vision loss → apoplexy in GH adenoma.

One-Line Recap

Pituitary apoplexy is acute hemorrhage or infarction of a pituitary adenoma producing sudden headache, visual loss, ophthalmoplegia, and acute secondary adrenal insufficiency — and the single decision that saves the patient is empiric IV hydrocortisone given before MRI confirmation.

Board pearl: If you remember one thing — cortisol before thyroid, steroids before scanner — you will answer almost every pituitary apoplexy question on Step 3 correctly.

Recognize: Thunderclap headache + bitemporal hemianopia + CN III palsy + hyponatremia/hypotension in a patient often with unrecognized macroadenoma; classic triggers include anticoagulation, cardiac surgery, postpartum hemorrhage (Sheehan), and dopamine agonist changes.

Stabilize: ABCs, isotonic fluids, hydrocortisone 100 mg IV bolus then 50 mg q6h before any other hormone; reverse anticoagulation; correct hyponatremia cautiously; MRI pituitary with contrast is gold standard while non-contrast CT may be normal.

Definitive care: Endoscopic transsphenoidal decompression within 7 days (≤72 h for severe/progressive visual loss or declining consciousness); conservative management with serial exams only if vision and mental status preserved; ICU admission with neurosurgery, endocrine, and ophthalmology consults.

Long term: Lifelong hormone replacement (cortisol first, then thyroid, then sex steroids, ± DDAVP and GH), sick day rules, injectable hydrocortisone kit, and medical alert ID at discharge; MRI surveillance, visual field testing, and endocrine follow-up; counsel on driving, fertility, bone health, and cardiovascular risk.