A56.4 — Chlamydial infection of pharynx
Is A56.4 billable?
Yes — A56.4 is billable for FY2027. A56.4 is a valid, billable ICD-10-CM code at the highest level of specificity in its branch. A56.4 may be submitted for encounters from October 1, 2026 through September 30, 2027.
A56.4 at a glance
| Code | A56.4 |
|---|---|
| Description | Chlamydial infection of pharynx |
| Billable | Yes |
| Code set | ICD-10-CM FY2027 |
| Valid for encounters | October 1, 2026 – September 30, 2027 |
Which MS-DRGs does A56.4 group to?
A56.4 sits in MDC Pre and helps define the logic of 3 MS-DRGs (version 44, FY2027). Which one a stay actually groups to also depends on procedures and secondary diagnoses.
- 011Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with MCCsurgical
- 012Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy with CCsurgical
- 013Tracheostomy for Face, Mouth and Neck Diagnoses or Laryngectomy without CC/MCCsurgical
How is A56.4 listed in the Alphabetic Index?
These are the routes through the Alphabetic Index that lead to A56.4. They show the wording a clinician may have documented, which often differs from the Tabular description.
- Chlamydia, chlamydial › pharyngitis
- Pharyngitis › chlamydial (acute) (catarrhal)(gangrenous) (infective) (malignant) (membranous) (phlegmonous) (pseudomembranous) (simple) (subacute) (suppurative) (ulcerative)
- Infection, infected, infective › Chlamydia, chlamydial › pharynx (opportunistic)
- Disease, diseased › venereal › chlamydial NEC › pharynx
Excludes1 — never code together — inherited from A50-A64
The conditions below can never be reported together with A56.4 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Excludes1 — never code together — inherited from A56
The conditions below can never be reported together with A56.4 on the same claim. An Excludes1 note means the two conditions cannot occur in the same patient, so reporting both is a coding error.
Use additional code — inherited from Chapter 1
Report an additional code alongside A56.4 to fully describe the condition. A56.4 is sequenced first.
- code to identify resistance to antimicrobial drugs (Z16.-)
Excludes2 — not included here — inherited from Chapter 1
The conditions below are not part of A56.4, but a patient may have both at the same time. When documentation supports it, A56.4 and the excluded code may both be reported.
- carrier or suspected carrier of infectious disease (Z22.-)
- certain localized infections - see body system-related chapters
- infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
- infectious and parasitic diseases specific to the perinatal period (P35-P39)
- influenza and other acute respiratory infections (J00-J22)
Excludes2 — not included here — inherited from A50-A64
The conditions below are not part of A56.4, but a patient may have both at the same time. When documentation supports it, A56.4 and the excluded code may both be reported.
- human immunodeficiency virus [HIV] disease (B20)
Excludes2 — not included here — inherited from A56
The conditions below are not part of A56.4, but a patient may have both at the same time. When documentation supports it, A56.4 and the excluded code may both be reported.
How long has A56.4 existed?
A56.4 has been in ICD-10-CM since at least FY2016, the earliest fiscal year on record here.
Derived from the official order files for FY2016–FY2026. FY2017 and FY2020 publish no order file, so those years are not covered.
Which conditions are coded to A56.4?
What other codes are in the A56 family? (5)
- A56.0Chlamydial infection of lower genitourinary tractnot billable
- A56.1Chlamydial infection of pelviperitoneum and other genitourinary organsnot billable
- A56.2Chlamydial infection of genitourinary tract, unspecified
- A56.3Chlamydial infection of anus and rectum
- A56.8Sexually transmitted chlamydial infection of other sites