A 38-year-old woman with moderate persistent asthma has been on inhaled fluticasone propionate 250 µg twice daily for 6 months. She reports hoarseness and oral candidiasis. To assess local adverse effects and guide further management, which investigation is most appropriate?

## Investigation of Choice for ICS Local Adverse Effects **Key Point:** Local adverse effects of inhaled corticosteroids (ICS)—hoarseness, dysphonia, and oral candidiasis—require direct visualization and microbiological confirmation, not systemic biomarkers. ### Why Oropharyngeal Swab + Laryngoscopy? 1. **Oral candidiasis confirmation**: Fungal culture of an oropharyngeal swab identifies *Candida albicans* or other species causing thrush, guiding antifungal therapy. 2. **Laryngoscopy assessment**: Direct visualization of the larynx reveals vocal cord changes, erythema, edema, or fungal plaques—the anatomical basis of hoarseness. 3. **Targeted diagnosis**: These investigations directly confirm the suspected local pathology rather than measuring systemic drug levels or bone effects. ### Why NOT the Other Options? | Investigation | Why Not Appropriate | |---|---| | **Serum cortisol + 24-h UFC** | Assesses systemic HPA-axis suppression; not relevant to local oropharyngeal symptoms. Fluticasone at 250 µg BID rarely causes clinically significant systemic absorption. | | **DEXA scan** | Screens for osteoporosis from chronic ICS use; not indicated for acute local adverse effects like candidiasis or hoarseness. | | **HPLC serum levels** | Fluticasone is highly protein-bound with minimal systemic bioavailability; serum levels do not guide management of local effects. | **Clinical Pearl:** Rinsing the mouth after each ICS dose and using a spacer reduce local adverse effects by 80%. If candidiasis is confirmed, topical antifungals (miconazole oral gel) or systemic fluconazole are first-line; ICS continuation is safe with antifungal cover. **High-Yield:** The question tests understanding that ICS adverse effects have two tiers—*local* (oropharyngeal, laryngeal) requiring direct visualization, and *systemic* (HPA suppression, osteoporosis) requiring biochemical or radiological screening. This patient's presentation is purely local.