What could be causing a bright yellow nasal discharge in a patient with a history of dermatomyositis, who has a normal computed tomography (CT) scan of the cervical and sinus areas, and experiences nasal dripping when moving forward, without blood or cough?

Bright Yellow Nasal Discharge with Postural Dripping in Dermatomyositis Patient

Most Likely Diagnosis

This presentation is most consistent with Upper Airway Cough Syndrome (UACS, formerly postnasal drip) secondary to rhinosinusitis, likely viral or non-allergic in origin given the normal CT imaging. 1, 2

The bright yellow discharge does not indicate bacterial sinusitis requiring antibiotics, as purulent-appearing nasal secretions are typical of viral infections and do not distinguish bacterial from viral etiology. 2 Yellow-green secretions can occur with extreme inflammation even in allergic conditions. 1

Key Clinical Reasoning

Why This Is Not Bacterial Sinusitis

• Normal CT scan from last year argues strongly against chronic bacterial sinusitis, as CT is the optimal technique for evaluating the paranasal sinuses and ostiomeatal complex. 1
• Purulent nasal secretions alone do not confirm bacterial infection—secretions become thicker and colored (yellow-green) after a few days in typical viral upper respiratory infections. 1
• Antibiotics should not be prescribed during the first week of symptoms, even with purulent discharge, as these findings are indistinguishable from viral rhinosinusitis. 2
• Bacterial sinusitis is suspected only if symptoms persist beyond 10 days without improvement, or if there is "double sickening" (initial improvement followed by worsening). 1, 2

Dermatomyositis Connection

• Dermatomyositis is a rare inflammatory myopathy with characteristic skin manifestations, and while nasal/sinus involvement is not a classic feature, the underlying immune dysregulation may predispose to rhinosinusitis. 3, 4
• The absence of blood in the discharge is reassuring, as it makes invasive fungal sinusitis (which can occur in immunocompromised patients) less likely. 1

Recommended Treatment Algorithm

First-Line Therapy (Start Immediately)

Initiate a first-generation antihistamine/decongestant combination for 1-2 weeks, as this is the most effective evidence-based treatment for UACS. 1, 2

• Specific effective combinations include dexbrompheniramine plus sustained-release pseudoephedrine, or azatadine plus sustained-release pseudoephedrine. 2
• To minimize sedation, start with once-daily dosing at bedtime for a few days before increasing to twice-daily therapy. 2
• Most patients will see improvement within days to 2 weeks of initiating therapy. 2

Important Contraindications to Monitor

• Monitor blood pressure after initiating decongestant therapy, as decongestants can cause hypertension, tachycardia, insomnia, and worsening of glaucoma. 2
• Common side effects include dry mouth and transient dizziness. 2

If No Improvement After 1-2 Weeks

Add intranasal corticosteroids (fluticasone 100-200 mcg daily) for a 1-month trial. 2

• Intranasal corticosteroids are effective for both allergic and non-allergic rhinitis-related UACS. 2
• A single randomized controlled trial showed that intranasal steroids given for 2 weeks are effective in allergic rhinitis-related cough. 2

Adjunctive Therapy

Consider high-volume nasal saline irrigation (150 mL), which improves outcomes through mechanical removal of mucus, enhanced ciliary activity, and disruption of inflammatory mediators. 2

• Nasal saline irrigation is more effective than saline spray because irrigation better expels secretions. 2
• Longer treatment duration (mean 7.5 months) shows better results than shorter courses. 2

When to Reassess and Consider Other Diagnoses

If Symptoms Persist After 2 Weeks of Adequate Treatment

Proceed with sequential evaluation for other common causes of chronic cough:

1. Asthma/non-asthmatic eosinophilic bronchitis - Consider bronchial provocation testing if spirometry is normal. 2
2. Gastroesophageal reflux disease (GERD) - Initiate empiric therapy with omeprazole 20-40 mg twice daily before meals for at least 8 weeks plus dietary modifications. 2
3. Obtain sinus imaging (radiographs or CT) if persistent nasal symptoms despite topical therapy—air-fluid levels would indicate acute bacterial sinusitis requiring antibiotics. 2

Red Flags Requiring Urgent Evaluation

• Fever, facial pain, proptosis, ophthalmoplegia, or facial necrosis suggest invasive fungal sinusitis, which can occur in immunocompromised patients (including those on immunosuppressive therapy for dermatomyositis). 1
• Unilateral symptoms, bone erosion on imaging, or bloody discharge should raise concern for malignancy, which has increased association with dermatomyositis. 5

Critical Pitfalls to Avoid

• Do not prescribe antibiotics empirically for yellow nasal discharge alone—this does not indicate bacterial infection. 2
• Newer-generation antihistamines are ineffective for non-allergic UACS; first-generation antihistamines with anticholinergic properties are superior. 2
• Never use topical nasal decongestants (oxymetazoline, xylometazoline) for more than 3-5 consecutive days due to the risk of rhinitis medicamentosa (rebound congestion). 2
• Approximately 20% of patients have "silent" postnasal drip with no obvious symptoms yet still respond to treatment, so consider UACS even without classic symptoms. 2
• Maintain all partially effective treatments rather than discontinuing them prematurely, as UACS, asthma, and GERD together account for approximately 90% of chronic cough cases. 2