A 28-year-old man from Delhi presents with severe throat pain for 3 days, difficulty swallowing, and fever (39.2°C). On examination, the right tonsil is enlarged, reddened, and covered with yellowish exudate. The uvula is pushed to the left. Intraoral palpation reveals a bulge in the soft palate above the tonsil with fluctuance. Trismus is absent. What is the most likely diagnosis?

## Clinical Diagnosis: Peritonsillar Abscess ### Key Clinical Features **Key Point:** Peritonsillar abscess is a collection of pus between the tonsillar capsule and the pharyngeal constrictor muscle, typically occurring as a complication of acute tonsillitis. The clinical presentation in this case is pathognomonic: | Feature | Finding | Significance | |---------|---------|---------------| | **Tonsillar enlargement** | Unilateral (right) | Suggests localized collection, not diffuse tonsillitis | | **Uvula deviation** | Pushed to left (away from lesion) | Indicates mass effect from abscess | | **Soft palate bulge** | Above tonsil with fluctuance | Confirms pus collection in peritonsillar space | | **Trismus** | Absent | Helps exclude retropharyngeal abscess (which causes marked trismus) | | **Fever & dysphagia** | Present | Systemic signs of suppuration | ### Pathophysiology 1. Acute bacterial tonsillitis → suppuration within tonsillar tissue 2. Pus tracks between tonsillar capsule and pharyngeal constrictor 3. Forms localized abscess in peritonsillar fossa (lateral pharyngeal wall, above tonsil) 4. Causes uvula displacement and soft palate bulging ### Diagnostic Confirmation **High-Yield:** Intraoral palpation with a gloved finger is the gold standard for detecting fluctuance. Imaging (CT/ultrasound) is reserved for atypical presentations or when diagnosis is unclear. ### Management Approach ```mermaid flowchart TD A[Peritonsillar Abscess Suspected]:::outcome --> B[Confirm Diagnosis]:::action B --> C{Fluctuance on Palpation?}:::decision C -->|Yes| D[Needle Aspiration/Incision & Drainage]:::action C -->|No| E[Imaging: CT/Ultrasound]:::action D --> F[Send Pus for Culture]:::action F --> G[Antibiotics + Supportive Care]:::action G --> H[Interval Tonsillectomy at 4-6 weeks]:::action ``` **Clinical Pearl:** Needle aspiration or incision and drainage is both therapeutic and diagnostic. Pus should be sent for culture and sensitivity. Empiric antibiotics (amoxicillin-clavulanate or cephalosporin) are started immediately. ### Complications if Untreated - Airway obstruction - Mediastinitis - Septicemia - Aspiration pneumonia [cite:Robbins & Cotran 10e Ch 16]