ICD‑9/10 and CPT Codes for Esophagitis/GERD (Bernstein Test Context)

ICD‑9‑CM (Legacy)

• 530.81 – Reflux esophagitis with esophagospasm
• 530.83 – Reflux esophagitis with ulcer
• 530.89 – Reflux esophagitis, unspecified

ICD‑10‑CM

• K21.0 – GERD with esophagitis
• K21.9 – GERD without esophagitis
• K20.x – Esophagitis (infectious, eosinophilic, etc.)

CPT

• 43237 – EGD with biopsy (often performed during Bernstein test evaluation)
• 91035 – Esophageal pH monitoring (modern replacement for Bernstein test)

Bernstein test (acid perfusion) is largely historical; current standard is 24‑hr pH/impedance monitoring.