2027 ICD-10-CM Diagnosis Code N99.842Postprocedural seroma of a genitourinary system organ or structure following a genitourinary system procedure

ICD-10-CM Codes›N00–N99›N99›N99

ICD-10-CM N99.842
CMSSource: CMS FY 2027 ICD-10-CM dataset · Effective Oct 1, 2026 – Sep 30, 2027

N99.842 is a billable ICD-10-CM diagnosis code for postprocedural seroma of a genitourinary system organ or structure following a genitourinary system procedure. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 919 through 921. As a secondary diagnosis, it counts as a complication or comorbidity (CC) and moves an inpatient stay to a higher severity level within its MS-DRG family. It does not count, however, when the principal diagnosis is one of 76 closely related codes. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Postprocedural or postoperative genitourinary system complication.

Code Identity

ICD-10-CM Code
N99.842
Billable Status
Yes — Valid for Submission
Code Describes
Postprocedural seroma of a genitourinary system organ or structure following a genitourinary system procedure
Short Description
Postproc seroma of a GU sys org following a GU sys procedure
Parent Code
N99.84
Postprocedural hematoma and seroma of a genitourinary system organ or structure following a procedure

Code Classification

ChapterN00–N99Diseases of the genitourinary system
SectionN99Intraoperative and postprocedural complications and disorders of genitourinary system, not elsewhere classified
CategoryN99Intraoperative and postprocedural complications and disorders of genitourinary system, not elsewhere classified
This CodeN99.842Postprocedural seroma of a genitourinary system organ or structure following a genitourinary system procedure

Instructional NotesGuidance

Instructions from the official ICD-10-CM Tabular List that apply to N99.842: its own notes plus those printed at N99 and Chapter 14. A note printed at a category, block or chapter applies to every code under it.

Excludes2

Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.

From N99 Intraoperative and postprocedural complications and disorders of genitourinary system, not elsewhere classified applies to 44 codes
  • irradiation cystitis (N30.4-)
  • postoophorectomy osteoporosis with current pathological fracture (M80.8-)
  • postoophorectomy osteoporosis without current pathological fracture (M81.8)
From Chapter 14 (N00-N99) Diseases of the genitourinary system applies to 838 codes
  • certain conditions originating in the perinatal period (P04-P96)
  • certain infectious and parasitic diseases (A00-B99)
  • complications of pregnancy, childbirth and the puerperium (O00-O9A)
  • congenital malformations, deformations and chromosomal abnormalities (Q00-Q99)
  • endocrine, nutritional and metabolic diseases (E00-E88)
  • injury, poisoning and certain other consequences of external causes (S00-T88)
  • neoplasms (C00-D49)
  • symptoms, signs and abnormal clinical and laboratory findings, not elsewhere classified (R00-R94)

Source: CMS ICD-10-CM Tabular List. How to read instructional notes.

Referenced in Other NotesGuidance

Instructional notes printed at other codes that name N99.842, its category, or a range that includes it.

Excludes2 2

These codes carry an Excludes2 note naming N99.842: its condition is not part of those codes, and both may be reported when the patient has both.

  • Block T80-T88 Complications of surgical and medical care, not elsewhere classified
    intraoperative and postprocedural complications of specified body systems (D78.-, E36.-, E89.-, G97.3-, G97.4, H59.3-, H59.-, H95.2-, H95.3, I97.4-, I97.5, J95.6-, J95.7, K91.6-, L76.-, M96.-, N99.-) names N99.-, which includes this code
  • T81 Complications of procedures, not elsewhere classified
    intraoperative and postprocedural complications of specific body system (D78.-, E36.-, E89.-, G97.3-, G97.4, H59.3-, H59.-, H95.2-, H95.3, I97.4-, I97.5, J95, K91.-, L76.-, M96.-, N99.-) names N99.-, which includes this code

Index to Diseases and InjuriesGuidance

Alphabetical index entries that point to this code.

Clinical ClassificationClinical

AHRQ’s CCSR groups this code into broader clinical categories.

CCSR GEN026
Postprocedural or postoperative genitourinary system complication
Default principal diagnosis: inpatient Yes · outpatient Yes

Convert N99.842 to ICD-9-CMHistory

The closest ICD-9-CM equivalents under the General Equivalence Mappings.

ICD-9-CM
998.13 Seroma complicting proc
Approximate The match is approximate rather than exact.

Code History & ChangesHistory

Replacement N99.842 replaces the following previously assigned code(s):

  • N99.820 - Postproc hemor of a GU sys org following a GU sys procedure
  • N99.820 - Postproc hemor/hemtom of a GU sys org fol a GU sys procedure
FY 2019AddedAdded to the ICD-10-CM code setEffective October 1, 2018.
FY 2020–2026No changes
FY 2027CurrentCurrent code set, no changesEffective October 1, 2026 through September 30, 2027.

Questions About N99.842Overview

Is N99.842 a billable code?

Yes. This is a billable ICD-10-CM code, specific enough to report postprocedural seroma of a genitourinary system organ or structure following a genitourinary system procedure on HIPAA-covered claims from October 1, 2026 through September 30, 2027.

What MS-DRG does N99.842 group to?

When postprocedural seroma of a genitourinary system organ or structure following a genitourinary system procedure is the principal diagnosis on an inpatient stay, it groups to MS-DRG 920, 919, 921, with relative weights from 0.6719 to 1.7624 depending on complications. Higher weights mean higher Medicare reimbursement.

Is N99.842 a CC or MCC?

CMS lists N99.842 as a CC (complication or comorbidity) for FY 2027. Reported as a secondary diagnosis, it moves the inpatient stay to a higher-weighted DRG within its severity family. It does not count when the principal diagnosis is one of the 76 closely related codes in its exclusion list.

What is the ICD-9 equivalent of N99.842?

Under the General Equivalence Mappings, postprocedural seroma of a genitourinary system organ or structure following a genitourinary system procedure converts to ICD-9-CM 998.13 (seroma complicting proc). The mapping is approximate, so confirm the match fits the documentation.