B96.21 Shiga toxin-producing Escherichia coli [E. coli] [STEC] O157 as the cause of diseases classified elsewhere

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The ICD-10-CM code for Shiga toxin-producing Escherichia coli [E. coli] [STEC] O157 as the cause of diseases classified elsewhere is B96.21 (FY2026). It is a billable, claim-ready diagnosis code.

Classification

Section
B95-B97: Bacterial and viral infectious agents (B95-B97)
Category B96
19 codes (16 billable)
FY2026 Status
Stable since FY2024

Also Known As

ICD-10-CM Alphabetic Index entries that lead to B96.21:

  • Escherichia coli (E. coli), as cause of disease classified elsewhere › O157
  • Escherichia coli (E. coli), as cause of disease classified elsewhere › O157:H- (nonmotile) with confirmation of Shiga toxin
  • Escherichia coli (E. coli), as cause of disease classified elsewhere › O157 with confirmation of Shiga toxin when H antigen is unknown, or is not H7
  • Escherichia coli (E. coli), as cause of disease classified elsewhere › O157:H7 with or without confirmation of Shiga toxin-production

Inclusion Terms

  • E. coli O157:H- (nonmotile) with confirmation of Shiga toxin
  • E. coli O157 with confirmation of Shiga toxin when H antigen is unknown, or is not H7
  • O157:H7 Escherichia coli [E. coli] with or without confirmation of Shiga toxin-production
  • Shiga toxin-producing Escherichia coli [E. coli] O157:H7 with or without confirmation of Shiga toxin-production
  • STEC O157:H7 with or without confirmation of Shiga toxin-production

U.S. Hospital Utilization

  • An estimated 725 U.S. inpatient stays in 2023 included B96.21 among the documented diagnoses.

Source: National Inpatient Sample (NIS), Healthcare Cost and Utilization Project (HCUP), Agency for Healthcare Research and Quality, 2016–2023. National survey-weighted estimates.

Official Coding Guidelines

HIV Infections (TOC entry)

a. Human Immunodeficiency Virus (HIV) Infections .............................................................. 19

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.1.a
Infectious agents causing diseases in other chapters (TOC)

b. Infectious agents as the cause of diseases classified to other chapters ................................. 22

— ICD-10-CM Official Guidelines for Coding and Reporting, FY2026, Section I.C.1.b

Source: CMS — ICD-10-CM Official Guidelines for Coding and Reporting, FY2026

References

Related Codes

Parent Code

B96 Other bacterial agents as the cause of diseases classified elsewhere

Related Codes in B96

B96 Other bacterial agents as the cause of diseases classified elsewhere B96.0 Mycoplasma pneumoniae [M. pneumoniae] as the cause of diseases classified elsewhere B96.1 Klebsiella pneumoniae [K. pneumoniae] as the cause of diseases classified elsewhere B96.2 Escherichia coli [E. coli ] as the cause of diseases classified elsewhere B96.20 Unspecified Escherichia coli [E. coli] as the cause of diseases classified elsewhere B96.22 Other specified Shiga toxin-producing Escherichia coli [E. coli] [STEC] as the cause of diseases classified elsewhere B96.23 Unspecified Shiga toxin-producing Escherichia coli [E. coli] [STEC] as the cause of diseases classified elsewhere B96.29 Other Escherichia coli [E. coli] as the cause of diseases classified elsewhere B96.3 Hemophilus influenzae [H. influenzae] as the cause of diseases classified elsewhere B96.4 Proteus (mirabilis) (morganii) as the cause of diseases classified elsewhere B96.5 Pseudomonas (aeruginosa) (mallei) (pseudomallei) as the cause of diseases classified elsewhere B96.6 Bacteroides fragilis [B. fragilis] as the cause of diseases classified elsewhere B96.7 Clostridium perfringens [C. perfringens] as the cause of diseases classified elsewhere B96.8 Other specified bacterial agents as the cause of diseases classified elsewhere B96.81 Helicobacter pylori [H. pylori] as the cause of diseases classified elsewhere B96.82 Vibrio vulnificus as the cause of diseases classified elsewhere B96.83 Acinetobacter baumannii as the cause of diseases classified elsewhere B96.89 Other specified bacterial agents as the cause of diseases classified elsewhere
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Reviewed by Prajwal Shrestha, CPC, CRC
Certified Professional Coder (CPC) and Certified Risk Adjustment Coder (CRC) · AAPC Member ID 01997614 · About · Editorial policy · Content last reviewed: 2025-10-01

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