2027 ICD-10-CM Diagnosis Code B35.9Dermatophytosis, unspecified
ICD-10-CM Codes›A00–B99›B35-B49›B35
- Billable — Valid for Submission
- Not Chronic
B35.9 is a billable ICD-10-CM diagnosis code for dermatophytosis, unspecified. It is valid on HIPAA claims for fiscal year 2027 (October 1, 2026 through September 30, 2027) and groups to MS-DRG 606 through 607. In AHRQ's Clinical Classifications Software (CCSR), this diagnosis falls under Fungal infections.
Code Identity
Code Classification
Approximate SynonymsGuidance
Alternate terms and clinical phrases that map to this code.
- Allergy-sensitivity to fungi syndrome
- Dermatophytosis
- Dermatophytosis caused by Microsporum praecox
- Dermatophytosis co-occurrent with human immunodeficiency virus infection
- Disseminated dermatophytosis
- Disseminated dermatophytosis due to immunodeficiency
- Favus caused by Lophophyton gallinae
- Favus caused by Trichophyton schoenleinii
- Id reaction
- Steroid-modified tinea infection
- Steroid-modified tinea infection of lower limb
- Tinea caused by Epidermophyton floccosum
- Tinea caused by Lophophyton gallinae
- Tinea caused by Microsporum audouinii
- Tinea caused by Microsporum canis variant canis
- Tinea caused by Microsporum equinum
- Tinea caused by Microsporum ferrugineum
- Tinea caused by Microsporum nanum
- Tinea caused by Nannizzia fulva
- Tinea caused by Nannizzia gypsea
- Tinea caused by Trichophyton
- Tinea caused by Trichophyton concentricum
- Tinea caused by Trichophyton equinum
- Tinea caused by Trichophyton interdigitale
- Tinea caused by Trichophyton mentagrophytes
- Tinea caused by Trichophyton mentagrophytes variant erinacei
- Tinea caused by Trichophyton persicolor
- Tinea caused by Trichophyton rubrum
- Tinea caused by Trichophyton simii
- Tinea caused by Trichophyton soudanense
- Tinea caused by Trichophyton tonsurans
- Tinea caused by Trichophyton verrucosum
- Tinea caused by Trichophyton violaceum
- Tinea caused by Trichophyton yaoundei
- Trichophytosis
Instructional NotesGuidance
Instructions from the official ICD-10-CM Tabular List that apply to B35.9: its own notes plus those printed at B35, block B35-B49, and Chapter 1. A note printed at a category, block or chapter applies to every code under it.
Includes
Further defines, or gives examples of, the content of the category.
- favus
- infections due to species of Epidermophyton, Micro-sporum and Trichophyton
- tinea, any type except those in B36.-
- diseases generally recognized as communicable or transmissible
Applicable To
Conditions this code is used for: synonyms of the title or, for "other specified" codes, the conditions assigned to it. The list is not exhaustive.
- Ringworm NOS
Excludes2
Not included here: the excluded condition is not part of this code, but a patient may have both, so both codes may be reported.
- carrier or suspected carrier of infectious disease (Z22.-)
- certain localized infections - see body system-related chapters
- 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
Add a second code, after this one, to fully describe the condition.
- code to identify resistance to antimicrobial drugs (Z16.-)
Source: CMS ICD-10-CM Tabular List. How to read instructional notes.
Index to Diseases and InjuriesGuidance
Alphabetical index entries that point to this code.
Ringworm B35.9
Clinical ClassificationClinical
AHRQ’s CCSR groups this code into broader clinical categories.
Clinical InformationClinical
Tinea
fungal infection of keratinized tissues such as hair, skin and nails. the main causative fungi include microsporum; trichophyton; and epidermophyton.
Patient EducationClinical
Fungal Infections
If you have ever had athlete's foot or a yeast infection, you can blame a fungus. A fungus is a primitive organism. Mushrooms, mold and mildew are examples. Fungi live in air, in soil, on plants and in water. Some live in the human body. Only about half of all types of fungi are harmful.
Read the full article at MedlinePlus
Courtesy of MedlinePlus, a service of the U.S. National Library of Medicine.
Convert B35.9 to ICD-9-CMHistory
The closest ICD-9-CM equivalents under the General Equivalence Mappings.
Code HistoryHistory
Questions About B35.9Overview
What is the ICD-10 code for dermatophytosis, unspecified?
The ICD-10-CM code for dermatophytosis, unspecified is B35.9 (sometimes written as B359). It is billable on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
Is B35.9 (Dermatophytosis) a billable code?
Yes. This is a billable ICD-10-CM code, specific enough to report dermatophytosis, unspecified on HIPAA-covered claims from October 1, 2026 through September 30, 2027.
What MS-DRG does B35.9 group to?
When dermatophytosis, unspecified is the principal diagnosis on an inpatient stay, it groups to MS-DRG 607, 606, with relative weights from 0.8772 to 1.5721 depending on complications. Higher weights mean higher Medicare reimbursement.
What is the ICD-9 equivalent of B35.9?
Under the General Equivalence Mappings, dermatophytosis, unspecified converts to ICD-9-CM 110.9 (dermatophytosis site NOS). The mapping is a direct match.
