TANDEM Cat® Feline Mammary Duct Impaction Severity Index (FMDISI)

Purpose

The TANDEM Cat® Feline Mammary Duct Impaction Severity Index (FMDISI) is an observational framework used to identify, document, and communicate mammary duct congestion and impaction in cats.

The scale allows team members to:

• Recognize mammary duct abnormalities

• Standardize documentation

• Improve communication between staff members

• Provide structured observations to guardians

• Support appropriate veterinary referral when indicated

The FMDISI is an observational tool and is not intended to diagnose medical conditions.

What Is Feline Mammary Duct Impaction?

Feline Mammary Duct Impaction (FMDI) occurs when glandular material accumulates within a mammary duct and is unable to drain normally.

Affected glands may become:

• Enlarged

• Firm

• Nodular

• Congested

In some cases, thick glandular material may be expressed from the nipple during routine handling or grooming.

Unlike mastitis, FMDI is not necessarily associated with infection.

Why It Matters

Many mammary abnormalities are discovered during grooming rather than veterinary examination because groomers routinely:

• Handle the entire body

• Separate the coat

• Bathe the abdomen

• Observe skin and glandular structures

Early identification allows guardians to seek veterinary evaluation when appropriate.

Common Clinical Findings

Mild Findings

• Slight nipple fullness

• Small glandular thickening

• Minimal discharge

Moderate Findings

• Palpable nodules

• Distinct gland enlargement

• Thick glandular material

Advanced Findings

• Large masses

• Significant swelling

• Inflammation

• Discomfort during handling

FMDISI Grading System

Grade 0 – Normal Mammary Tissue

Findings

• Mammary tissue soft and flat

• No palpable fullness

• No discharge

• No gland enlargement

Interpretation

No evidence of mammary duct obstruction.

Action

No intervention required.

Document only if relevant to the examination.

Grade 1 – Mild Duct Congestion

Findings

• Slight fullness around nipple

• Small glandular thickening

• Minimal expression possible

Interpretation

Early duct accumulation.

Action

Document findings.

Continue observation.

No active intervention typically required.

Grade 2 – Moderate Duct Impaction

Findings

• Distinct glandular enlargement

• Palpable nodules

• Thick glandular material expressed with gentle pressure

Interpretation

Moderate duct obstruction.

Action

Document location and findings.

Notify guardian.

Recommend monitoring and veterinary discussion if persistent.

Grade 3 – Severe Impaction

Findings

• Firm glandular swelling

• Significant enlargement

• Thick waxy or paste-like material

Interpretation

Significant duct blockage.

Action

Document thoroughly.

Notify guardian.

Recommend veterinary evaluation.

Photograph findings when appropriate and consented.

Grade 4 – Advanced Duct Compaction

Findings

• Large glandular mass

• Dense material present

• Possible inflammation

• Possible irritation

• Significant enlargement

Interpretation

Advanced obstruction requiring veterinary assessment.

Infection, mastitis, or neoplastic processes must be ruled out by a veterinarian.

Action

Immediate documentation.

Immediate guardian notification.

Strong recommendation for veterinary evaluation.

Leadership notification when appropriate.

Documentation Standards

Whenever mammary abnormalities are observed, record:

Location

Identify affected gland whenever possible.

Example:

Left cranial abdominal gland.

Grade

Assign FMDISI score.

Example:

FMDISI Grade 2.

Findings

Describe observations objectively.

Example:

Moderate gland enlargement with thick white glandular material expressed during bathing.

Cat Response

Document comfort level.

Example:

No discomfort observed.

or

Cat demonstrated sensitivity during palpation.

Sample Chart Note

During abdominal assessment, a moderate enlargement was observed near the right caudal mammary gland. Gentle expression produced thick white glandular material. Cat remained tolerant throughout examination. Findings consistent with FMDISI Grade 2. Guardian informed and advised to discuss findings with veterinarian if changes persist or worsen.

Trauma-Informed Handling Standards

When mammary abnormalities are identified:

Do

• Use gentle handling

• Minimize palpation

• Observe carefully

• Prioritize comfort

• Document findings

Do Not

• Repeatedly manipulate glands

• Force expression

• Attempt aggressive removal

• Cause discomfort for diagnostic purposes

The goal is observation, not extraction.

Veterinary Referral Criteria

Recommend veterinary evaluation when any of the following are present:

• Painful swelling

• Warmth

• Redness

• Persistent discharge

• Rapid enlargement

• Ulceration

• Fever

• Lethargy

• Multiple affected glands

• Grade 3 or Grade 4 findings

Differential Considerations

FMDI observations should never be presented as a diagnosis.

Potential veterinary differentials may include:

• Mammary duct impaction

• Mastitis

• Mammary hyperplasia

• Mammary tumors

• Abscess formation

• Inflammatory conditions

Diagnosis remains the responsibility of a veterinarian.

Related TANDEM Cat® Frameworks

This index works alongside:

• TANDEM Cat® Matting Severity Scale

• TANDEM Cat® Sound Sensitivity Scale (TCSSS)

• Feline Glandular Expression Grading (FGEG)

• Transitional Stress Anorexia (TSA) Protocol

• Pre-Felt Somatic Entrapment Syndrome (PFSES)

Together these frameworks transform grooming observations into structured clinical information that supports better feline care.

Key Takeaway

Feline Mammary Duct Impaction is frequently discovered during grooming because of the extensive hands-on assessment involved in feline coat care.

The purpose of the FMDISI is to help staff consistently identify, document, communicate, and escalate mammary findings while maintaining a trauma-informed, observation-based approach that prioritizes feline comfort and safety.