## Clinical Context This patient has biochemically and radiologically confirmed Cushing disease (pituitary microadenoma with elevated ACTH). He has severe complications (hypertensive crisis, new-onset diabetes, osteoporotic fracture) that require urgent cortisol reduction before definitive surgery. ## Rationale for Cortisol-Lowering Therapy Before Surgery **Key Point:** Patients with severe, symptomatic Cushing syndrome should have cortisol reduced pharmacologically BEFORE transsphenoidal surgery to minimize perioperative morbidity and mortality. **High-Yield:** Preoperative cortisol reduction improves: - Hypertension control and cardiovascular stability - Glucose metabolism and diabetes management - Immune function and wound healing - Muscle strength and bone metabolism ## Ketoconazole: First-Line Preoperative Agent | Feature | Ketoconazole | Mitotane | Metyrapone | |---------|--------------|----------|------------| | **Onset** | 3–5 days | Slow (weeks–months) | 24–48 hours | | **Use** | Preoperative cortisol reduction | Adrenocortical carcinoma | Preoperative or bridge | | **Monitoring** | LFTs, cortisol levels | LFTs, lipids, cortisol | Electrolytes, cortisol | | **Advantage** | Rapid, reversible | Long-acting | Rapid | | **Disadvantage** | Hepatotoxicity risk | Teratogenic, slow | Electrolyte shifts | **Clinical Pearl:** Ketoconazole blocks 11β-hydroxylase and multiple cytochrome P450 enzymes, rapidly lowering cortisol. It is the preferred agent for preoperative stabilization in Cushing disease. ## Management Algorithm ```mermaid flowchart TD A[Cushing disease confirmed]:::outcome --> B{Severe complications?}:::decision B -->|Yes| C[Start ketoconazole]:::action C --> D[Target cortisol reduction to low-normal]:::action D --> E[Monitor BP, glucose, electrolytes]:::action E --> F[Transsphenoidal surgery when stable]:::action B -->|No/mild| G[Proceed to transsphenoidal surgery]:::action F --> H[Intraoperative ACTH monitoring]:::action G --> H H --> I{ACTH drop >50%?}:::decision I -->|Yes| J[Likely cure]:::outcome I -->|No| K[Incomplete resection - consider adjuvant]:::outcome ``` **Mnemonic:** **KETOCONAZOLE PRE-OP** = Ketoconazole Enables Treatment Optimization; Cortisol reduction Obviates periOperative complications; Normalizes Adrenal output; Zaps 11β-hydroxylase; Optimizes surgical outcome; Lowers mortality; Ensures stable hemodynamics. [cite:Harrison 21e Ch 375; Endocrine Society Clinical Practice Guidelines for Cushing Syndrome] 
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