What is the next step in management for a 40‑year‑old HIV‑positive man on Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide) who presents with a two‑day history of severe left‑sided sore throat radiating to the ear, left pre‑auricular, upper neck and jaw swelling, a discolored left mandibular molar, white‑blood‑cell count of 12.1 ×10⁹/L, lactate of 1.9 mmol/L, and negative rapid strep, influenza, and COVID‑19 tests?

Odontogenic Infection with Soft Tissue Swelling: Immediate Surgical Consultation and Empiric Antibiotics

The next step is immediate consultation with oral and maxillofacial surgery or otolaryngology for evaluation of a potential deep space neck infection (Ludwig's angina or submandibular space infection), combined with urgent initiation of empiric intravenous antibiotics covering oral flora. This patient presents with a dental source (discolored mandibular molar) and progressive soft tissue swelling involving the pre-auricular, upper neck, and jaw regions—classic signs of an odontogenic infection with potential spread to fascial spaces 1.

Immediate Management Priorities

Surgical Evaluation

• Obtain immediate surgical consultation (oral surgery, ENT, or general surgery depending on institutional availability) for assessment of airway compromise risk and need for incision and drainage 1.
• The progression from tooth pain to soft tissue swelling over 24 hours indicates rapid spread, which can involve submandibular, sublingual, or lateral pharyngeal spaces 1.
• Even without fever, the WBC of 12.1 × 10⁹/L suggests active infection requiring urgent intervention 2.

Airway Assessment

• Evaluate for signs of impending airway compromise: difficulty swallowing, drooling, stridor, or inability to handle secretions 1.
• Patients with HIV (even with undetectable viral load on Biktarvy) may have altered inflammatory responses, potentially masking the severity of infection 3, 2.
• The radiation of pain to the ear suggests possible involvement of deeper fascial planes 1.

Empiric Antibiotic Therapy

Initial Regimen

• Start IV ampicillin-sulbactam 3g every 6 hours OR piperacillin-tazobactam 3.375g every 6 hours to cover oral anaerobes (Prevotella, Fusobacterium) and aerobes (Streptococcus viridans, Staphylococcus) 2, 1.
• Alternative: IV clindamycin 600-900mg every 8 hours PLUS a beta-lactam if patient has penicillin allergy 1.
• Do not use macrolide monotherapy in this HIV-positive patient due to increased risk of drug-resistant organisms 2.

HIV-Specific Considerations

• While this patient has undetectable HIV on Biktarvy (bictegravir/emtricitabine/tenofovir alafenamide), his immune function should be considered 3, 4.
• Bictegravir has minimal drug-drug interactions with most antibiotics, making antibiotic selection straightforward 5, 6.
• No adjustment to his HIV regimen is needed; continue Biktarvy without interruption 3, 7.

Diagnostic Imaging

CT Scan with IV Contrast

• Obtain urgent CT of the neck with IV contrast to define the extent of infection, identify abscess formation, and assess for involvement of deep neck spaces 1.
• CT is superior to clinical examination for detecting early abscess formation and guiding surgical planning 1.
• Do not delay imaging if surgical consultation is immediately available, but imaging should not delay antibiotics 2.

Source Control

Dental Extraction

• The infected tooth must be extracted once the acute infection is controlled 1.
• Attempting extraction during active cellulitis risks spreading infection; stabilize with antibiotics first unless abscess drainage is required 1.
• Coordinate with oral surgery for definitive management within 24-48 hours 1.

Common Pitfalls to Avoid

• Do not discharge this patient with oral antibiotics alone: Progressive soft tissue swelling in the neck requires inpatient management due to airway risk 1.
• Do not assume the negative strep/flu/COVID tests rule out serious bacterial infection: These tests are irrelevant to odontogenic infections 3, 1.
• Do not delay treatment waiting for cultures: Blood cultures should be drawn, but empiric therapy must start immediately 2.
• Do not underestimate infection severity based on absence of fever: Afebrile presentation does not exclude serious deep space infection, particularly in immunocompromised hosts 3, 2.

Monitoring Parameters

• Serial airway assessments every 2-4 hours initially 1.
• Repeat WBC and lactate in 12-24 hours to assess response 2.
• Clinical improvement (reduced swelling, improved pain) should occur within 48-72 hours of appropriate therapy 2, 1.
• If no improvement by 48 hours, consider imaging for abscess requiring drainage 1.