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  6. 2024 ICD-10-CM Code L99

2024 ICD-10-CM Diagnosis Code L99

Other disorders of skin and subcutaneous tissue in diseases classified elsewhere

ICD-10-CM Code:
L99
ICD-10 Code for:
Oth disorders of skin, subcu in diseases classd elswhr
Is Billable?
Yes - Valid for Submission
Chronic Condition Indicator: [1]
Not chronic
Code Navigator:

Code Classification

  • Diseases of the skin and subcutaneous tissue
    (L00–L99)
    • Other disorders of the skin and subcutaneous tissue
      (L80-L99)
      • Other disorders of skin and subcutaneous tissue in diseases classified elsewhere
        (L99)

L99 is a billable diagnosis code used to specify a medical diagnosis of other disorders of skin and subcutaneous tissue in diseases classified elsewhere. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2023 through September 30, 2024.

Approximate Synonyms

The following clinical terms are approximate synonyms or lay terms that might be used to identify the correct diagnosis code:

  • Acute Chagas' disease
  • African trypanosomiasis affecting skin
  • Amyloidosis cutis dyschromia
  • Amyloidosis limited to skin
  • Behcet disease of skin
  • Chagas' exanthem
  • Cutaneous complication of rheumatoid disease
  • Cutaneous complication of systemic sclerosis
  • Dermatosis resulting from vascular insufficiency
  • Disorder of skin co-occurrent with human immunodeficiency virus infection
  • Disorder of skin co-occurrent with human immunodeficiency virus infection
  • Disorder of skin due to human immunodeficiency virus infection
  • Human immunodeficiency virus modified skin disease
  • Metabolic and nutritional disorders affecting skin
  • Non-specific cutaneous reaction in Hodgkin's disease
  • Primary localized cutaneous amyloidosis
  • Rheumatoid neutrophilic dermatitis
  • Skin disorder with AIDS
  • Skin involvement in bacterial endocarditis
  • Skin lesion in drug addict
  • Small vessel thrombosis of skin
  • Spinal cord defect affecting skin
  • Systemic disease affecting skin
  • Trypanosomiasis affecting skin
  • Trypanosomiasis affecting skin

Clinical Classification

Tabular List of Diseases and Injuries

The following annotation back-references are applicable to this diagnosis code. The Tabular List of Diseases and Injuries is a list of ICD-10-CM codes, organized "head to toe" into chapters and sections with coding notes and guidance for inclusions, exclusions, descriptions and more.


Code First

Code First
Certain conditions have both an underlying etiology and multiple body system manifestations due to the underlying etiology. For such conditions, the ICD-10-CM has a coding convention that requires the underlying condition be sequenced first followed by the manifestation. Wherever such a combination exists, there is a "use additional code" note at the etiology code, and a "code first" note at the manifestation code. These instructional notes indicate the proper sequencing order of the codes, etiology followed by manifestation.
  • underlying disease, such as:
  • amyloidosis E85

Type 1 Excludes

Type 1 Excludes
A type 1 excludes note is a pure excludes note. It means "NOT CODED HERE!" An Excludes1 note indicates that the code excluded should never be used at the same time as the code above the Excludes1 note. An Excludes1 is used when two conditions cannot occur together, such as a congenital form versus an acquired form of the same condition.

Code Edits

The Medicare Code Editor (MCE) detects and reports errors in the coding of claims data. The following ICD-10-CM Code Edits are applicable to this code:

  • Manifestation diagnoses - Manifestation codes describe the manifestation of an underlying disease, not the disease itself, and therefore should not be used as a principal diagnosis.

Convert L99 to ICD-9-CM

  • ICD-9-CM Code: 701.8 - Skin hypertro/atroph NEC
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.
  • ICD-9-CM Code: 709.8 - Skin disorders NEC
    Approximate Flag - The approximate mapping means there is not an exact match between the ICD-10 and ICD-9 codes and the mapped code is not a precise representation of the original code.

Patient Education


Skin Conditions

What does your skin do?

Your skin is your body's largest organ. It covers the entire outside of your body. There are many ways that your skin protects your body and helps keep you healthy. For example, it:

  • Holds body fluids in, which helps prevent you from getting dehydrated
  • Keeps out harmful germs, which helps prevent infections
  • Helps you feel things like heat, cold, and pain
  • Helps control your body temperature
  • Makes vitamin D when the sun shines on it
  • Shields your body against heat and light

What problems and conditions can affect your skin?

There are many different problems and conditions which can affect your skin. Some of them can cause uncomfortable symptoms, such as itching, burning, redness, and rashes. They might also affect your appearance. Some of the more common skin conditions include:

  • Acne, which causes pimples when hair follicles under your skin get clogged up
  • Burns
  • Cuts and scrapes
  • Dandruff, flaking of the skin on your scalp (the top of your head)
  • Eczema (atopic dermatitis), which causes inflammation, redness, and irritation of the skin
  • Hives, which are red and sometimes itchy bumps on your skin
  • Insect bites
  • Psoriasis, which causes itchy, scaly red patches
  • Skin cancer
  • Skin infections

How can I keep my skin healthy?

Since your skin protects your body in many ways, it's important to try to keep your skin healthy. For example, you can:

  • Wear the right protective equipment, like gloves, long sleeves, knee and elbow pads, or helmets to protect against cuts, bumps and scrapes.
  • If you do get a cut or scrape, clean it right away with soap and warm water. Put on a bandage to protect it while it heals.
  • When you are spending time outdoors, wear long sleeves and pants and use insect repellant to prevent insect bites.
  • Prevent sunburn by covering up and using sunscreen when outdoors.
  • Wash your hands often with soap and water.
  • When you take a shower or bath, use warm (not hot) water. Use mild cleansers and wash gently (don't scrub).
  • Use moisturizers, like lotions, creams, or ointments, to prevent dry skin.

NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases


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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.