How Is RP Distinguished From GPA and Ear Infection?

Relapsing polychondritis (RP), granulomatosis with polyangiitis (GPA, a type of blood vessel inflammation), and severe ear infections can all cause painful, red, and swollen ears or nasal issues. Determining the exact cause is complex, as symptoms strongly overlap, and an infection can even happen at the same time as an autoimmune flare ^[1].

Doctors distinguish them by carefully examining the pattern of inflammation, checking for involvement of other organs, and running targeted lab tests or scans. Because treatments for RP and GPA suppress the immune system, ruling out—or treating—an infection in parallel is critical ^[2]. Never stop, skip, or change your immunosuppressant medications without explicit instructions from your doctor, as sudden changes can be dangerous.

Distinguishing Relapsing Polychondritis from Ear Infections

It is common for an initial RP flare to be mistaken for an ear infection ^[1]. However, infections like auricular perichondritis (infection of the ear cartilage) or otitis externa (swimmer’s ear) require different treatments ^[3][4].

• Earlobe Sparing: A hallmark of RP is that it attacks cartilage, meaning inflammation affects the rigid upper ear but spares the soft, fleshy earlobe ^[5]. However, this is not a foolproof way to rule out an infection: bacterial auricular perichondritis also attacks cartilage and spares the earlobe ^[3]. Skin infections (cellulitis) typically involve the entire ear, including the lobe ^[6].
• Drainage and Triggers: Ear infections may follow an injury, piercing, or water exposure, and might produce pus or fluid from the ear canal ^[3][4]. However, an infection can still happen without a clear trigger or visible drainage.
• Cultures: If there is fluid, doctors may take a swab for a culture to grow bacteria. While identifying bacteria (like Pseudomonas) points to an infection, a negative swab does not safely rule one out, as deeper infections might not show up on a surface swab ^[3].
• Response to Antibiotics: If your ear does not improve on antibiotics, it might be an autoimmune condition like RP—but it could also mean the bacteria are resistant, an abscess has formed, or the medication cannot penetrate the cartilage ^[1][7]. Never use an antibiotic trial as a home diagnostic test. If symptoms persist or worsen, contact your doctor for prompt reassessment.

Distinguishing Relapsing Polychondritis from GPA

Both RP and GPA are autoimmune conditions that can cause a “saddle-nose” deformity (collapse of the nasal bridge), sinus crusting, and inflamed ear cartilage ^[5][8]. Clinicians look for several clues to separate them:

• Kidneys and Lungs: GPA frequently attacks the kidneys and the lung tissue (causing nodules or bleeding) ^[9][10]. Doctors check for this using chest scans, urine tests (to look for hidden blood or protein), and blood tests for creatinine (a marker of kidney function) ^[9][10]. RP primarily targets cartilage and airways. However, early GPA can be localized to the nose or ears without kidney or lung involvement, so normal tests do not completely rule out GPA.
• Airway Patterns: Both diseases can restrict breathing, but scans (like CT) or camera exams (bronchoscopy) may show different patterns. GPA tends to cause narrowing just below the vocal cords (subglottic) in a complete circle ^[11][12]. RP usually affects the lower windpipe and the tubes leading into the lungs (bronchi), often sparing the flat back wall of the windpipe (posterior tracheal membrane) ^[11][12]. These are clues for specialists to interpret, not absolute rules.
• ANCA Blood Tests: A blood test for ANCA (antineutrophil cytoplasmic antibodies) helps guide the diagnosis. A positive PR3-ANCA result strongly supports GPA, but it is not definitive ^[9]. Some GPA patients test negative, and rarely, an RP patient might test positive, so doctors must look at the whole clinical picture ^[13][14].
• Biopsies: If it is safe to do so, doctors may take a small tissue sample (biopsy). A GPA biopsy might show granulomas (clusters of immune cells) and inflamed blood vessels (vasculitis), while an RP biopsy often shows degenerating cartilage ^[10][15]. However, a non-diagnostic biopsy does not completely exclude either condition.

When to Seek Urgent or Emergency Care

Because symptoms overlap and conditions can be dangerous if left untreated, it is vital to know when to seek help.

Go to an emergency room immediately if you experience:

• New or worsening difficulty breathing
• Stridor (a high-pitched, noisy whistling sound when breathing in)
• Sudden changes in your voice, severe hoarseness, or inability to swallow
• Coughing up blood
• A severe reduction in how much you are urinating

Contact your specialist the same day for an urgent assessment if you experience:

• A hot, rapidly worsening, or very red ear
• New pus-like drainage from the ear or nose
• A new fever or spreading facial swelling