A 32-year-old woman from Delhi presents with a 3-day history of severe oral pain, difficulty swallowing, and fever (38.5°C). On examination, she has multiple painful vesicles on the buccal mucosa, tongue, and palate with surrounding erythema. She denies any prior episodes. Tzanck smear shows multinucleated giant cells. She is immunocompetent with no contraindications to antivirals. What is the most appropriate immediate next step in management?

Explanation

## Clinical Presentation & Diagnosis **Key Point:** Primary herpes simplex stomatitis (HSV-1) presents with painful vesicles on the oral mucosa, fever, and systemic symptoms. Tzanck smear showing multinucleated giant cells is a rapid, bedside confirmation of herpesvirus infection. ## Why IV Acyclovir Is Correct **High-Yield:** In immunocompetent patients with primary HSV stomatitis, IV acyclovir is the gold standard when: - Severe oropharyngeal involvement with dysphagia is present (risk of dehydration) - Systemic symptoms (fever, malaise) are marked - Oral bioavailability may be compromised due to difficulty swallowing **Clinical Pearl:** The standard IV dosing is 5 mg/kg every 8 hours (15 mg/kg/day total). Before initiation, always check: 1. Serum creatinine (acyclovir is renally cleared; dose adjustment needed if CrCl < 50 mL/min) 2. Hydration status (IV acyclovir can precipitate in renal tubules if patient is dehydrated) 3. Infusion rate (infuse over ≥1 hour to minimize nephrotoxicity) **Mnemonic:** **BEFORE IV ACYCLOVIR** = **B**aseline creatinine, **H**ydration, **E**lectrolytes, **F**luid status, **O**verall renal function, **R**ate of infusion (slow). ## Treatment Efficacy Timeline | Antiviral | Route | Bioavailability | Onset | Use Case | |-----------|-------|-----------------|-------|----------| | Acyclovir | IV | 100% | Rapid (2–3 hrs) | Severe primary HSV, immunocompromised, CNS involvement | | Acyclovir | Oral | 15–20% | Slower (4–6 hrs) | Mild–moderate recurrent HSV, immunocompetent | | Valacyclovir | Oral | 54% (prodrug of acyclovir) | Moderate | Recurrent HSV, VZV; NOT for primary severe disease | | Topical acyclovir | Cream | Minimal systemic | Very slow | Adjunct only; inadequate for systemic disease | ## Why Oral Antivirals Are Insufficient Here Oral acyclovir (400–800 mg 5× daily) or valacyclovir (500 mg 3× daily) have poor bioavailability and slow onset. In a patient with severe dysphagia and systemic toxicity, oral therapy risks: - Delayed symptom relief - Continued viral replication during the critical first 48–72 hours - Dehydration from inadequate fluid intake **Warning:** Do NOT delay IV therapy while awaiting PCR confirmation—clinical + Tzanck smear is sufficient to start treatment immediately.