2020 ICD-10-CM Diagnosis Code B35.1

Tinea unguium

    2016 2017 2018 2019 2020 Billable/Specific Code
  • B35.1 is a billable/specific ICD-10-CM code that can be used to indicate a diagnosis for reimbursement purposes.
  • The 2020 edition of ICD-10-CM B35.1 became effective on October 1, 2019.
  • This is the American ICD-10-CM version of B35.1 - other international versions of ICD-10 B35.1 may differ.
Applicable To
  • Dermatophytic onychia
  • Dermatophytosis of nail
  • Onychomycosis
  • Ringworm of nails
The following code(s) above B35.1 contain annotation back-references
Annotation Back-References
In this context, annotation back-references refer to codes that contain:
  • Applicable To annotations, or
  • Code Also annotations, or
  • Code First annotations, or
  • Excludes1 annotations, or
  • Excludes2 annotations, or
  • Includes annotations, or
  • Note annotations, or
  • Use Additional annotations
that may be applicable to B35.1:
  • A00-B99
    2020 ICD-10-CM Range A00-B99

    Certain infectious and parasitic diseases

    Includes
    • diseases generally recognized as communicable or transmissible
    Type 1 Excludes
    • certain localized infections - see body system-related chapters
    Type 2 Excludes
    • carrier or suspected carrier of infectious disease (Z22.-)
    • infectious and parasitic diseases complicating pregnancy, childbirth and the puerperium (O98.-)
    • infectious and parasitic diseases specific to the perinatal period (P35-P39)
    • influenza and other acute respiratory infections (J00-J22)
    Use Additional
    • code to identify resistance to antimicrobial drugs (Z16.-)
    Certain infectious and parasitic diseases
  • B35-B49
    2020 ICD-10-CM Range B35-B49

    Mycoses

    Type 2 Excludes
    • hypersensitivity pneumonitis due to organic dust (J67.-)
    • mycosis fungoides (C84.0-)
    Mycoses
  • B35
    ICD-10-CM Diagnosis Code B35

    Dermatophytosis

      2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
    Includes
    • favus
    • infections due to species of Epidermophyton, Micro-sporum and Trichophyton
    • tinea, any type except those in B36.-
    Dermatophytosis
Approximate Synonyms
  • Onychomycosis
  • Onychomycosis (nail fungal infection)
  • Onychomycosis/dystrophy
  • Total dystrophic onychomycosis
Clinical Information
  • A fungal infection of the nail, usually caused by dermatophytes; yeasts; or nondermatophyte molds.
ICD-10-CM B35.1 is grouped within Diagnostic Related Group(s) (MS-DRG v37.0):
  • 606 Minor skin disorders with mcc
  • 607 Minor skin disorders without mcc

Convert B35.1 to ICD-9-CM

Code History
  • 2016 (effective 10/1/2015): New code (first year of non-draft ICD-10-CM)
  • 2017 (effective 10/1/2016): No change
  • 2018 (effective 10/1/2017): No change
  • 2019 (effective 10/1/2018): No change
  • 2020 (effective 10/1/2019): No change

Diagnosis Index entries containing back-references to B35.1:
  • Dermatophytosis (epidermophyton) (infection) (Microsporum) (tinea) (Trichophyton) B35.9
    ICD-10-CM Diagnosis Code B35.9

    Dermatophytosis, unspecified

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Ringworm NOS
    • nail B35.1
  • Infection, infected, infective (opportunistic) B99.9
    ICD-10-CM Diagnosis Code B99.9

    Unspecified infectious disease

      2016 2017 2018 2019 2020 Billable/Specific Code
    • finger (skin) L08.9
      ICD-10-CM Diagnosis Code L08.9

      Local infection of the skin and subcutaneous tissue, unspecified

        2016 2017 2018 2019 2020 Billable/Specific Code
      • nail L03.01-
        ICD-10-CM Diagnosis Code L03.01-

        Cellulitis of finger

          2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
        Applicable To
        • Felon
        • Whitlow
        Type 1 Excludes
        • fungus B35.1
    • fungus NOS B49
      ICD-10-CM Diagnosis Code B49

      Unspecified mycosis

        2016 2017 2018 2019 2020 Billable/Specific Code
      Applicable To
      • Fungemia NOS
      • skin B36.9
        ICD-10-CM Diagnosis Code B36.9

        Superficial mycosis, unspecified

          2016 2017 2018 2019 2020 Billable/Specific Code
        • toenails B35.1
      • nail B35.1
    • nail (chronic)
      • finger L03.01-
        ICD-10-CM Diagnosis Code L03.01-

        Cellulitis of finger

          2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
        Applicable To
        • Felon
        • Whitlow
        Type 1 Excludes
        • fungus B35.1
      • toe L03.03-
        ICD-10-CM Diagnosis Code L03.03-

        Cellulitis of toe

          2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
        • fungus B35.1
    • toe (skin) L08.9
      ICD-10-CM Diagnosis Code L08.9

      Local infection of the skin and subcutaneous tissue, unspecified

        2016 2017 2018 2019 2020 Billable/Specific Code
      • cellulitis L03.03-
        ICD-10-CM Diagnosis Code L03.03-

        Cellulitis of toe

          2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
        • fungus B35.1
      • nail L03.03-
        ICD-10-CM Diagnosis Code L03.03-

        Cellulitis of toe

          2016 2017 2018 2019 2020 Non-Billable/Non-Specific Code
        • fungus B35.1
  • Mycosis, mycotic B49
    ICD-10-CM Diagnosis Code B49

    Unspecified mycosis

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Fungemia NOS
    • nails B35.1
  • Onychia - see also Cellulitis, digit
    • dermatophytic B35.1
  • Onychomycosis B35.1 (finger) (toe)
  • Ringworm B35.9
    ICD-10-CM Diagnosis Code B35.9

    Dermatophytosis, unspecified

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Ringworm NOS
    • nails B35.1
  • Tinea (intersecta) (tarsi) B35.9
    ICD-10-CM Diagnosis Code B35.9

    Dermatophytosis, unspecified

      2016 2017 2018 2019 2020 Billable/Specific Code
    Applicable To
    • Ringworm NOS
    • unguium B35.1

ICD-10-CM Codes Adjacent To B35.1
B34 Viral infection of unspecified site
B34.0 Adenovirus infection, unspecified
B34.1 Enterovirus infection, unspecified
B34.2 Coronavirus infection, unspecified
B34.3 Parvovirus infection, unspecified
B34.4 Papovavirus infection, unspecified
B34.8 Other viral infections of unspecified site
B34.9 Viral infection, unspecified
B35 Dermatophytosis
B35.0 Tinea barbae and tinea capitis
B35.1 Tinea unguium
B35.2 Tinea manuum
B35.3 Tinea pedis
B35.4 Tinea corporis
B35.5 Tinea imbricata
B35.6 Tinea cruris
B35.8 Other dermatophytoses
B35.9 Dermatophytosis, unspecified
B36 Other superficial mycoses
B36.0 Pityriasis versicolor
B36.1 Tinea nigra

Reimbursement claims with a date of service on or after October 1, 2015 require the use of ICD-10-CM codes.