Is ICD-10-CM code P77 billable?

No, P77 (Necrotizing enterocolitis of newborn) is a non-billable ICD-10-CM code. It must be coded to a more specific subcategory before it can be used for reimbursement.

What chapter does ICD-10-CM code P77 belong to?

P77 belongs to Chapter 16 of the ICD-10-CM tabular list: P00–P96 (Certain Conditions Originating in the Perinatal Period).

P77Not billable, use a more specific code below

Necrotizing enterocolitis of newborn

In Digestive system disorders of newborn (P76-P78), chapter 16: Certain Conditions Originating in the Perinatal Period

4 billable codes under P77: all are an MCC; all map to HCC 78 (Intestinal Obstruction/Perforation).A CC or MCC (major CC) is a secondary diagnosis that raises the MS-DRG payment. An HCC counts toward a Medicare Advantage patient's risk score.

Official coding guidelines

From the ICD-10-CM Official Guidelines for Coding and Reporting, FY 2027 (CMS and NCHS). Links open the PDF at the right page.

Coding of conditions that originate from before birth through the 28th day after birth, including newborn record rules, prematurity, low birth weight, sepsis, and stillbirth.

General Perinatal Rules (page 71)
Observation and Evaluation of Newborns for Suspected Conditions not Found (page 73)
Coding Additional Perinatal Diagnoses (page 73)
Prematurity and Fetal Growth Retardation (page 73)
Low birth weight and immaturity status (page 74)
Bacterial Sepsis of Newborn (page 74)
Stillbirth (page 74)
COVID-19 Infection in Newborn (page 74)

Read Section I.C.16 (page 71)

All codes under P77

P77 can't be used on a claim. Pick a billable code below; grey headings group them.

P77 MS-DRGs

As the principal diagnosis, all 4 billable codes under P77 group to MS-DRG 791 or 793 (v44.0). Which one applies depends on procedures performed, secondary diagnoses (CC/MCC), and the patient's age and discharge status.

Other codes that refer to P77

Notes on these codes point to P77.

K55 Excludes1: necrotizing enterocolitis of newborn (P77.-)
K55.3 Excludes1: necrotizing enterocolitis of newborn (P77.-)
P37 Excludes2: necrotizing enterocolitis in newborn (P77.-)

About the condition

Plain-language background from MedlinePlus (National Library of Medicine), not coding guidance.

Premature Babies

Almost 1 of every 10 infants born in the United States are premature, or preemies. A premature birth is when a baby is born before 37 completed weeks of pregnancy. A full-term pregnancy is 40 weeks.

Small Intestine Disorders

Your small intestine is the longest part of your digestive system - about twenty feet long! It connects your stomach to your large intestine (or colon) and folds many times to fit inside your abdomen. Your small intestine does most of the digesting of the foods you eat. It has three areas called the duodenum, the ileum, and the jejunum.

Code history

Valid since FY2016, when ICD-10-CM took effect on October 1, 2015. No changes since.