A74.81 Chlamydial peritonitis

Billable ICD-10-CM code, FY2026.

Applies from A74 Other diseases caused by chlamydiae

Excludes1 (never code together)

• neonatal chlamydial conjunctivitis (P39.1)
• neonatal chlamydial pneumonia (P23.1)
• Reiter's disease (M02.3-)
• sexually transmitted chlamydial diseases (A55-A56)

Excludes2 (not included here)

• chlamydial pneumonia (J16.0)

MS-DRG index

Defines the logic of DRG(s) 865-866 in MDC 18.

Approximate ICD-9-CM (GEMs)

• 079.88 Other specified chlamydial infection (approximate)

Code annotations containing back-references to A74.81

Back-references to A74.81

• Type 1 Excludes: K65 Peritonitis ("peritonitis in chlamydia (A74.81)")
• Type 1 Excludes: K67 Disorders of peritoneum in infectious diseases classified elsewhere ("peritonitis in chlamydia (A74.81)")

Back-references to A74

• Type 2 Excludes: A56 Other sexually transmitted chlamydial diseases ("conditions classified to A74.-")

Diagnosis Index entries for A74.81

• Chlamydia, chlamydial › peritonitis
• Fitzhugh-Curtis syndrome › due to › Chlamydia trachomatis
• Peritonitis (adhesive) (bacterial) (fibrinous) (hemorrhagic) (idiopathic) (localized) (perforative) (primary) (with adhesions) (with effusion) › chlamydial
• Syndrome › Fitzhugh-Curtis › due to › Chlamydia trachomatis

Nearby codes

• A74 Other diseases caused by chlamydiae
• A74.0 Chlamydial conjunctivitis
• A74.8 Other chlamydial diseases
• A74.81 Chlamydial peritonitis (this code)
• A74.89 Other chlamydial diseases
• A74.9 Chlamydial infection, unspecified