L02.31

Cutaneous abscess of buttock

A cutaneous abscess of the buttock is a localized collection of purulent material (pus) that develops within the dermis or deeper subcutaneous tissues of the gluteal region. Pathologically, it is characterized by an acute inflammatory response to bacterial invasion, most commonly caused by Staphylococcus aureus, including methicillin-resistant strains (MRSA). The abscess forms as the body attempts to wall off the infection, resulting in a painful, erythematous, and fluctuant mass. Anatomically, the buttock is susceptible to abscess formation due to the presence of numerous hair follicles, sweat glands, and substantial subcutaneous fat, coupled with frequent mechanical stressors such as pressure from sitting and friction from clothing. Clinical evaluation typically reveals localized warmth, induration, and tenderness. While small abscesses may occasionally resolve with warm compresses, the clinical standard of care for a mature, fluctuant gluteal abscess is surgical incision and drainage (I&D). If untreated, the infection may extend into the deeper fascial planes, leading to cellulitis, the formation of complex fistulous tracts, or systemic bacteremia.

Clinical Symptoms

  • Localized, intense pain and tenderness in the gluteal region
  • Palpable, fluctuant mass (feeling of fluid under the skin)
  • Localized erythema (redness) and increased skin temperature
  • Swelling and induration (hardening) of surrounding tissues
  • Spontaneous purulent drainage from a central necrotic point
  • Discomfort or mechanical difficulty when sitting or walking
  • Systemic symptoms such as fever, chills, and fatigue in advanced cases
  • Regional lymphadenopathy in the inguinal area
  • Pruritus or skin irritation surrounding the lesion
  • Reduced range of motion in the hip due to pain

Common Causes

  • Staphylococcus aureus infection (most common primary etiology)
  • Infection by Methicillin-resistant Staphylococcus aureus (MRSA)
  • Progression of folliculitis or a furuncle into a deeper abscess
  • Secondary infection of a pre-existing pilar or sebaceous cyst
  • Minor skin trauma, abrasions, or lacerations to the gluteal skin
  • Hidradenitis suppurativa (chronic inflammatory skin condition)
  • Diabetes mellitus (increased susceptibility to skin infections)
  • Obesity (increased friction, moisture, and skin folds in the gluteal region)
  • Immunosuppression due to chronic illness or medication
  • Poor local hygiene leading to bacterial colonization and follicle blockage

Documentation & Coding Tips

Distinguish between cutaneous abscess, furuncle, and carbuncle within the gluteal region.

Example: Patient presents with a 4 cm fluctuant, erythematous mass on the left buttock. Assessment confirms a cutaneous abscess of the buttock (L02.31) rather than a furuncle (L02.32) or carbuncle (L02.33). Patient has Type 2 Diabetes Mellitus with hyperglycemia (E11.65), increasing the risk of recurrent skin infections.

Billing Focus: Documenting the specific morphology (abscess vs furuncle) ensures the most specific ICD-10-CM code selection within the L02 category.

Document the presence or absence of associated cellulitis and its specific location.

Example: Clinical evaluation of a right gluteal abscess (L02.31) reveals 5 cm of surrounding warmth and macular erythema consistent with cellulitis of the buttock (L03.317). Both codes are reported to reflect the total clinical burden.

Billing Focus: Coding both the abscess (L02.31) and the cellulitis (L03.317) provides a complete picture of the infection and justifies a higher level of medical decision making.

Clearly differentiate a gluteal cutaneous abscess from a pilonidal cyst with abscess.

Example: Abscess is located 8 cm lateral to the midline on the left buttock cheek. No sinus tract or involvement of the coccygeal region is noted, excluding pilonidal cyst (L05.01). Diagnosis: Cutaneous abscess of left buttock (L02.31).

Billing Focus: The L02.31 code is specific to the buttock skin, while L05.01 is specific to the pilonidal/sacral region; miscoding leads to claim denials or audits.

Specify the causative organism if known via culture results.

Example: Wound culture from the buttock abscess (L02.31) returned positive for Methicillin-resistant Staphylococcus aureus (B95.62). Patient is started on appropriate targeted antibiotic therapy.

Billing Focus: Adding the B95.62 code as a secondary diagnosis identifies the infection as MRSA-related, which often requires more resource-intensive management.

Record the size and depth of the abscess and any involvement of deeper structures.

Example: A 6 cm cutaneous abscess of the right buttock (L02.31) was identified. Bedside ultrasound confirms the abscess is limited to the skin and subcutaneous tissue with no involvement of the underlying gluteal muscle or fascia.

Billing Focus: Documentation of size and depth justifies the use of CPT 10061 (Complex Incision and Drainage) over 10060 (Simple).

Relevant CPT Codes