A 38-year-old man from Delhi presents with a 2-year history of progressive nasal obstruction, rhinorrhea, and post-nasal drip. He reports recurrent episodes of acute sinusitis treated with antibiotics. On examination, pale, smooth, glistening masses are seen bilaterally in the nasal cavity. Nasal endoscopy confirms multiple polyps arising from the maxillary and ethmoid sinuses. CT paranasal sinuses shows bilateral polypoid masses without bone erosion. His medical history is significant for childhood-onset asthma and chronic diarrhea since age 12. What is the most likely diagnosis?

Explanation

## Clinical Presentation and Diagnosis **Key Point:** The combination of bilateral nasal polyposis, chronic sinusitis, childhood-onset asthma, and chronic diarrhea is pathognomonic for cystic fibrosis (CF). ### Why Cystic Fibrosis? Cystic fibrosis is an autosomal recessive disorder affecting the CFTR gene, leading to abnormal mucus production and impaired mucociliary clearance. Nasal polyposis occurs in 15–50% of CF patients and is one of the earliest manifestations. **High-Yield:** The classic triad in CF patients with ENT involvement: 1. Bilateral nasal polyposis (pale, smooth, gelatinous appearance) 2. Chronic/recurrent sinusitis 3. Conductive hearing loss (due to serous otitis media from Eustachian tube dysfunction) ### Pathophysiology Thickened mucus in the paranasal sinuses and nasal cavity leads to: - Obstruction of sinus ostia - Secondary bacterial infection - Polyp formation from chronic inflammation - Absence of bone erosion (unlike malignancy or aggressive lesions) ### Associated Features in CF | Feature | Frequency | Mechanism | |---------|-----------|----------| | Nasal polyposis | 15–50% | Chronic inflammation, impaired clearance | | Chronic sinusitis | >90% | Mucus stasis, recurrent infection | | Asthma | 30–50% | Airway hyperresponsiveness | | Pancreatic insufficiency | 85% | Duct obstruction, acinar atrophy | | Failure to thrive | Variable | Malabsorption, chronic diarrhea | **Clinical Pearl:** Nasal polyposis in a child or young adult with asthma and GI symptoms should raise suspicion for CF. Sweat chloride test (≥60 mmol/L) and CFTR genetic testing confirm diagnosis. ### Management Approach ```mermaid flowchart TD A[Bilateral nasal polyps + asthma + diarrhea]:::outcome --> B[Suspect CF]:::decision B --> C[Sweat chloride test]:::action C --> D{≥60 mmol/L?}:::decision D -->|Yes| E[Confirm CF diagnosis]:::outcome D -->|No| F[Consider other causes]:::outcome E --> G[Nasal topical steroids + saline irrigation]:::action E --> H[Endoscopic polypectomy if obstructive]:::action E --> I[Systemic CF management]:::action ``` **Key Point:** Nasal steroids (fluticasone nasal spray) are first-line for CF-related nasal polyposis; surgical polypectomy is reserved for obstructive cases or failed medical management.