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  6. 2025 ICD-10-CM Code A27
Version 2025
Non-Billable Code

2025 ICD-10-CM Diagnosis Code A27

Leptospirosis

ICD-10-CM Code:
A27
ICD-10 Code for:
Leptospirosis
Is Billable?
Not Valid for Submission
Code Navigator:

A27 is a non-specific and non-billable diagnosis code code, consider using a code with a higher level of specificity for a diagnosis of leptospirosis. The code is not specific and is NOT valid for the year 2025 for the submission of HIPAA-covered transactions. Category or Header define the heading of a category of codes that may be further subdivided by the use of 4th, 5th, 6th or 7th characters.

Specific Coding Applicable to Leptospirosis

Non-specific codes like A27 require more digits to indicate the appropriate level of specificity. Consider using any of the following ICD-10-CM codes with a higher level of specificity when coding for leptospirosis:

  • Use A27.0 for Leptospirosis icterohemorrhagica - BILLABLE CODE

  • A27.8 for Other forms of leptospirosis - NON-BILLABLE CODE

  • Use A27.81 for Aseptic meningitis in leptospirosis - BILLABLE CODE

  • Use A27.89 for Other forms of leptospirosis - BILLABLE CODE

  • Use A27.9 for Leptospirosis, unspecified - BILLABLE CODE

Code Classification

  • Certain infectious and parasitic diseases
    (A00–B99)
    • Certain zoonotic bacterial diseases
      (A20-A28)
      • Leptospirosis
        (A27)

Clinical Information

  • Leptospirosis

    infections with bacteria of the genus leptospira.

  • Weil Disease

    a severe form of leptospirosis, usually caused by leptospira interrogans serovar icterohaemorrhagiae and occasionally other serovars. it is transmitted to humans by the rat and is characterized by hemorrhagic and renal symptoms with accompanying jaundice.

  • Leptospira

    a genus of aerobic, helical spirochetes, some species of which are pathogenic, others free-living or saprophytic.

Patient Education


Bacterial Infections

What are bacteria?

Bacteria are tiny organisms (living things) that have only one cell. Under a microscope, they look like balls, rods, or spirals. They can be found almost everywhere on Earth. There are lots of bacteria in and on your body. In fact, your body has about 10 times more bacteria cells than human cells.

There are many different types of bacteria. Most types don't make you sick. Some types are helpful. For example, "good" bacteria in your digestive system can help your body digest food and absorb vitamins and minerals. They can help protect you from getting sick. Bacteria are also used in making foods like yogurt and cheese.

But some types of bacteria can cause an infection and make you sick. They are called infectious bacteria. These bacteria can reproduce quickly in your body. Many of them give off toxins (poisons) that can damage your cells and make you sick. Other types can move into and damage your tissues. A few examples of bacteria that cause infections include Streptococcus, Staphylococcus, and E. coli.

How do bacterial infections spread?

There are different ways that bacterial infections may spread:

  • Through droplets and particles that are breathed out by someone who has the infection. You might breathe in the droplets or particles, or they could land on your mouth, nose, or eyes.
  • By touching surfaces or objects that have the bacteria on them and then touching your mouth, nose, or eyes.
  • Through cuts, scrapes, and skin-to-skin contact with someone who has the infection.
  • From the pregnant parent to the baby during pregnancy.
  • Through contaminated food or water.
  • By being bitten by an infected insect or animal.
  • Through sexual contact (usually vaginal, anal and oral sex) with someone who has the infection.

What are the treatments for bacterial infections?

Sometimes your immune system may be able to fight off a bacterial infection. But when you do need treatment, it will be with antibiotics.

When you take antibiotics, follow the directions carefully. Each time you take them, there is a risk that the bacteria will become resistant to the effects of the antibiotics. This is called antibiotic resistance. When this happens, the bacteria are not killed, and they continue to grow. They can cause resistant infections, which can be difficult, and sometimes impossible, to treat.

Can bacterial infections be prevented?

You can help prevent some bacterial infections by:

  • Getting vaccines that protect against bacterial infections.
  • Having good hygiene habits. These include washing your hands often and covering your mouth and nose when coughing or sneezing.
  • Paying attention to food safety.
  • Cleaning and disinfecting surfaces that your frequently touch.
  • Preventing insect bites by using a U.S. Environmental Protection Agency (EPA)-registered insect repellent. when you go outdoors. If you travel to an area that has a high risk of diseases from insect bites, also wear long pants, shirts, and socks.
  • Practicing safe sex. This means using a latex condom every time you have anal, vaginal, or oral sex. If your or your partner is allergic to latex, you can use polyurethane condoms.
  • Avoiding close contact with people who are sick.

[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.