In an 11‑year‑old child presenting with sore throat, painful neck, and limited neck flexion, what are the differential diagnoses and appropriate management plan?

Differential Diagnosis and Management of an 11-Year-Old with Sore Throat, Painful Neck, and Inability to Flex Neck

This child requires immediate evaluation for retropharyngeal abscess or other deep neck space infection, which are life-threatening conditions that present with neck pain and limited neck flexion.

Critical Red Flags Present

• Inability to flex the neck is a hallmark of retropharyngeal abscess (RPA) or deep neck infection, not simple pharyngitis; 45% of children with RPA present with limitation of neck extension, 36.5% with torticollis, and 12.5% with limitation of neck flexion 1.
• Painful neck with movement restriction suggests meningitis, neck soft-tissue infection, or upper respiratory infection complications that require management separate from routine cervical neck pain guidelines 2.
• Deep neck infections are potentially life-threatening and may present with obscure complaints that delay diagnosis 3.

Priority Differential Diagnoses

1. Retropharyngeal Abscess (Most Urgent)

• Clinical presentation: Neck pain (38% of cases), fever (17%), sore throat (17%), and limitation of neck movement—especially difficulty extending the neck to look up 1.
• Age distribution: 75% of RPA cases occur in children younger than 5 years, but the median age is 36 months; this 11-year-old is older than typical but still at risk 1.
• Key physical finding: Limited neck extension is more common than limited flexion, but both can occur 1.
• Airway risk: Respiratory distress or stridor occurs in only 5% of cases initially but can progress rapidly 1.

2. Parapharyngeal or Peritonsillar Abscess

• Epidemiology: Peritonsillar (24.3%) and parapharyngeal space infections (24.3%) are the most common deep neck infections in children 3.
• Presentation: Fever (93.3%) and painful swelling of the neck (70%) are typical 3.
• Unilateral tonsillar bulge with uvular deviation suggests peritonsillar abscess and mandates urgent ENT referral 4.

3. Bacterial Meningitis

• Classic triad: Fever, neck stiffness (nuchal rigidity), and altered mental status.
• Neck flexion limitation (Brudzinski sign) is a key meningeal sign.
• Requires immediate empiric therapy without awaiting diagnostic confirmation 5.

4. Group A Streptococcal Pharyngitis with Cervical Lymphadenitis

• Typical features: Sudden-onset sore throat, fever, tonsillopharyngeal erythema, tender anterior cervical lymphadenopathy, and absence of viral symptoms 2, 5.
• However, inability to flex the neck is NOT typical of uncomplicated streptococcal pharyngitis and suggests a suppurative complication 2.

5. Diphtheria (Rare but Serious)

• Presentation: Sore throat with toxic appearance, characteristic membrane, and potential airway obstruction 6, 7.
• Requires hospitalization if suspected 6.

Immediate Diagnostic Workup

Step 1: Assess Airway and Hemodynamic Stability

• Evaluate for stridor, respiratory distress, drooling, or toxic appearance that would indicate impending airway compromise 8, 3.
• Airway management is paramount to survival; aggressive early intervention is required if epiglottitis or severe RPA is suspected 8.

Step 2: Obtain Contrast-Enhanced CT Scan of the Neck

• CT scan is the definitive imaging modality to distinguish retropharyngeal abscess from retropharyngeal cellulitis and to identify other deep neck space infections 1, 3.
• CT should be performed urgently in any child with neck pain and limited neck movement 3.
• Performance of surgical drainage is significantly associated with CT scan findings; CT helps guide the decision between antibiotics alone versus surgical intervention 1.

Step 3: Laboratory Studies

• Complete blood count with differential: Deep neck infections typically show leukocytosis with neutrophilia and left shift 5.
• Blood cultures: Obtain before initiating antibiotics 3.
• Throat culture or rapid antigen detection test (RADT): Only if simple pharyngitis remains in the differential after imaging excludes abscess 2, 5.

Step 4: Lumbar Puncture (If Meningitis Suspected)

• Perform after CT scan if there are no contraindications (e.g., signs of increased intracranial pressure, focal neurologic deficits).
• Do not delay empiric antibiotics while awaiting lumbar puncture if bacterial meningitis is suspected 5.

Management Algorithm

If CT Shows Retropharyngeal or Deep Neck Abscess

Antibiotic Therapy

• Empiric broad-spectrum IV antibiotics covering Staphylococcus aureus (most common pathogen, 27.3%) and viridans streptococci (22.7%) 3.
• Suggested regimen: Ampicillin-sulbactam or clindamycin plus a third-generation cephalosporin (e.g., ceftriaxone) to cover aerobic and anaerobic organisms 3.

Surgical Intervention

• 27 (42%) of RPA patients require surgical drainage; the decision is guided by CT findings 1.
• Some patients with defined abscess on CT (37%) can be treated successfully with antibiotics alone, but close monitoring is essential 1.
• Urgent ENT consultation is mandatory for all cases 1, 3.

Expected Course

• Mean hospitalization duration is 7.9 days (range 2–18 days) 3.
• Complications are rare (occurred in only 2 of 30 patients in one series) but include recurrence and pulmonary edema 3.

If CT Shows Retropharyngeal Cellulitis (No Abscess)

• Most patients can be treated successfully with IV antibiotics alone without surgery 1.
• Hospitalization for close monitoring is required because cellulitis can progress to abscess 1.

If Imaging Excludes Abscess and Meningitis

Test for Group A Streptococcus

• Perform RADT in children aged 5–15 years with fever, sore throat, and no viral features (cough, rhinorrhea, hoarseness, conjunctivitis) 2, 5.
• A negative RADT must be followed by a backup throat culture in children because RADT sensitivity is only 80–90% 2, 5.

Treatment for Confirmed GAS Pharyngitis

• First-line: Amoxicillin 50 mg/kg once daily (max 1 g) or penicillin V 250 mg 2–3 times daily for 10 days 2, 5.
• Penicillin-allergic (non-anaphylactic): First-generation cephalosporin (cephalexin or cefadroxil) for 10 days 2, 5.
• Penicillin-allergic (anaphylactic): Clindamycin 20 mg/kg/day divided three times daily (max 1.8 g/day) for 10 days or azithromycin 12 mg/kg once daily (max 500 mg) for 5 days 2, 5.

Treatment for Viral Pharyngitis

• Withhold antibiotics entirely; provide only symptomatic care with ibuprofen or acetaminophen 5, 9.

Common Pitfalls to Avoid

• Do not assume this is simple pharyngitis based on the chief complaint of "sore throat"; inability to flex the neck is a red flag for serious pathology 1, 3.
• Do not delay imaging in a child with neck pain and limited neck movement; CT scan should be performed urgently 3.
• Do not rely on the absence of respiratory distress to rule out RPA; stridor and wheezing occur in only 1.5% of cases initially 1.
• Do not treat empirically with oral antibiotics for presumed pharyngitis when deep neck infection is possible; this child requires hospitalization and IV therapy 6, 3.
• Do not perform lumbar puncture before CT scan if there is concern for increased intracranial pressure or focal neurologic deficits.

Disposition

• Immediate hospitalization is required for any child with sore throat, toxic appearance, and neck movement limitation 6.
• Urgent ENT and/or infectious disease consultation should be obtained 3.
• Close airway monitoring is essential because deep neck infections can progress to airway compromise 8, 3.