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  6. 2025 ICD-10-CM Code A33

2025 ICD-10-CM Diagnosis Code A33

Tetanus neonatorum

ICD-10-CM Code:
A33
ICD-10 Code for:
Tetanus neonatorum
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Not chronic
Code Navigator:

A33 is a billable diagnosis code used to specify a medical diagnosis of tetanus neonatorum. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2024 through September 30, 2025.

The code A33 is applicable to newborn patients only. It is clinically and virtually impossible to use this code on a non-newborn patient.

Code Classification

  • Certain infectious and parasitic diseases
    A00–B99
    • Other bacterial diseases
      A30-A49
      • Tetanus neonatorum
        A33

Approximate Synonyms

The following list of clinical terms are approximate synonyms, alternative descriptions, or common phrases that might be used by patients, healthcare providers, or medical coders to describe the same condition. These synonyms and related diagnosis terms are often used when searching for an ICD-10 code, especially when the exact medical terminology is unclear. Whether you're looking for lay terms, similar diagnosis names, or common language alternatives, this list can help guide you to the correct ICD-10 classification.

  • Autonomic disorder due to tetanus
  • Disorder of autonomic nervous system due to infectious disease
  • Localized tetanus
  • Omphalitis
  • Tetanic opisthotonus
  • Tetanus neonatorum
  • Tetanus omphalitis
  • Tetanus with trismus
  • Trismus
  • Trismus present

Clinical Classification

Clinical Classifications group individual ICD-10-CM diagnosis codes into broader, clinically meaningful categories. These categories help simplify complex data by organizing related conditions under common clinical themes.

They are especially useful for data analysis, reporting, and clinical decision-making. Even when diagnosis codes differ, similar conditions can be grouped together based on their clinical relevance. Each category is assigned a unique CCSR code that represents a specific clinical concept, often tied to a body system or medical specialty.

Bacterial infections

CCSR Code: INF003

Inpatient Default: N - Not default inpatient assignment for principal diagnosis or first-listed diagnosis.

Outpatient Default: N - Not default outpatient assignment for principal diagnosis or first-listed diagnosis.

Perinatal infections

CCSR Code: PNL009

Inpatient Default: Y - Yes, default inpatient assignment for principal diagnosis or first-listed diagnosis.

Outpatient Default: Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.

Clinical Information

  • Trismus

    spasmodic contraction of the masseter muscle resulting in forceful jaw closure. this may be seen with a variety of diseases, including tetanus, as a complication of radiation therapy, trauma, or in association with neoplastic conditions.

  • Tetanus

    a disease caused by tetanospasmin, a powerful protein toxin produced by clostridium tetani. tetanus usually occurs after an acute injury, such as a puncture wound or laceration. generalized tetanus, the most common form, is characterized by tetanic muscular contractions and hyperreflexia. localized tetanus presents itself as a mild condition with manifestations restricted to muscles near the wound. it may progress to the generalized form.

  • Omphalitis

    inflammation of the umbilical cord stump in newborns.

  • Funisitis

    an acute inflammation of the umbilical cord. it is characterized by the presence of polymorphonuclear cells migrating from the fetal umbilical cord vessels through the umbilical cord towards the bacteria containing amniotic fluid.

  • Necrotizing Funisitis|Sclerosing Funisitis|Sclerosing Funisitis

    a ring of karyorrhectic debris that may exhibit dystrophic mineralization and/or identifiable fetal neutrophil infiltrate in wharton's jelly that is oriented towards the amniotic surface. the cord has a denser ring externally and a fainter ring centrally.

  • Grade 1 Trismus, CTCAE|CTCAE Grade 1 Trismus (difficulty, restriction or pain when opening mouth)|Grade 1 Trismus|Grade 1 Trismus (difficulty, restriction or pain when opening mouth)

    decreased rom (range of motion) without impaired eating

  • Grade 2 Trismus, CTCAE|CTCAE Grade 2 Trismus (difficulty, restriction or pain when opening mouth)|Grade 2 Trismus|Grade 2 Trismus (difficulty, restriction or pain when opening mouth)

    decreased rom requiring small bites, soft foods or purees

  • Grade 3 Trismus, CTCAE|CTCAE Grade 3 Trismus (difficulty, restriction or pain when opening mouth)|Grade 3 Trismus|Grade 3 Trismus (difficulty, restriction or pain when opening mouth)

    decreased rom with inability to adequately aliment or hydrate orally

  • Trismus

    lack of ability to open the mouth fully due to decreased range of motion of the muscles of mastication. it may be a symptom of tetanus.

  • Trismus, CTCAE|Trismus|Trismus|Trismus (difficulty, restriction or pain when opening mouth)

    a disorder characterized by lack of ability to open the mouth fully due to a decrease in the range of motion of the muscles of mastication.

Index to Diseases and Injuries References

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

Code Edits

The Medicare Code Editor (MCE) detects errors and inconsistencies in ICD-10-CM diagnosis coding that can affect Medicare claim validity. These Medicare code edits help medical coders and billing professionals determine when a diagnosis code is not appropriate as a principal diagnosis, does not meet coverage criteria. Use this list to verify whether a code is valid for Medicare billing and to avoid claim rejections or denials due to diagnosis coding issues.

Perinatal / Newborn diagnoses

The Medicare Code Editor detects inconsistencies in perinatal / newborn cases by checking a patient's age and any diagnosis on the patient's record. The newborn code edits apply to patients age 0 years only; a subset of diagnoses which will only occur during the perinatal or newborn period of age 0 (e.g., tetanus neonatorum, health examination for newborn under 8 days old).

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Convert A33 to ICD-9-CM

Below are the ICD-9 codes that most closely match this ICD-10 code, based on the General Equivalence Mappings (GEMs). This ICD-10 to ICD-9 crosswalk tool is helpful for coders who need to reference legacy diagnosis codes for audits, historical claims, or approximate code comparisons.

Tetanus neonatorum

ICD-9-CM: 771.3

This is a direct match with no additional mapping qualifiers. The absence of a flag generally means the mapping is considered exact or precise. In other words, the ICD-10 code maps cleanly to the ICD-9 code without qualification, approximation, or needing multiple codes.

View Conversion

Patient Education


Tetanus

Tetanus is a serious illness caused by Clostridium bacteria. The bacteria live in soil, saliva, dust, and manure. The bacteria can enter the body through a deep cut, like those you might get from stepping on a nail, or through a burn.

The infection causes painful tightening of the muscles, usually all over the body. It can lead to "locking" of the jaw. This makes it impossible to open your mouth or swallow. Tetanus is a medical emergency. You need to get treatment in a hospital.

A vaccine can prevent tetanus. It is given as a part of routine childhood vaccination. Adults should get a tetanus shot, or booster, every 10 years. If you get a bad cut or burn, see your doctor - you may need a booster. Immediate and proper wound care can prevent tetanus infection.


[Learn More in MedlinePlus]

Uncommon Infant and Newborn Problems

It can be scary when your baby is sick, especially when it is not an everyday problem like a cold or a fever. You may not know whether the problem is serious or how to treat it. If you have concerns about your baby's health, call your health care provider right away.

Learning information about your baby's condition can help ease your worry. Do not be afraid to ask questions about your baby's care. By working together with your health care provider, you make sure that your baby gets the best care possible.


[Learn More in MedlinePlus]

Code History

  • FY 2024 - No Change, effective from 10/1/2023 through 9/30/2024
  • FY 2023 - No Change, effective from 10/1/2022 through 9/30/2023
  • FY 2022 - No Change, effective from 10/1/2021 through 9/30/2022
  • FY 2021 - No Change, effective from 10/1/2020 through 9/30/2021
  • FY 2020 - No Change, effective from 10/1/2019 through 9/30/2020
  • FY 2019 - No Change, effective from 10/1/2018 through 9/30/2019
  • FY 2018 - No Change, effective from 10/1/2017 through 9/30/2018
  • FY 2017 - No Change, effective from 10/1/2016 through 9/30/2017
  • FY 2016 - New Code, effective from 10/1/2015 through 9/30/2016. This was the first year ICD-10-CM was implemented into the HIPAA code set.

Footnotes

[1] Not chronic - A diagnosis code that does not fit the criteria for chronic condition (duration, ongoing medical treatment, and limitations) is considered not chronic. Some codes designated as not chronic are acute conditions. Other diagnosis codes that indicate a possible chronic condition, but for which the duration of the illness is not specified in the code description (i.e., we do not know the condition has lasted 12 months or longer) also are considered not chronic.