Special Senses & Otolaryngology

Peritonsillar abscess in pediatrics

Clinical Overview and When to Suspect Peritonsillar Abscess

— Aerobes: Group A Streptococcus (most common), Staph aureus (including MRSA), Haemophilus

— Anaerobes: Fusobacterium necrophorum, Prevotella, Peptostreptococcus, Bacteroides

— Severe unilateral throat pain out of proportion to exam

— Trismus (limited mouth opening from pterygoid irritation)

— "Hot potato" / muffled voice

— Drooling, odynophagia, ipsilateral ear pain (referred via CN IX)

— Fever, malaise, neck stiffness or torticollis toward affected side

Board pearl: The triad of trismus + muffled voice + uvular deviation in a febrile teen with sore throat is PTA until proven otherwise — image only if you cannot examine adequately or suspect a deeper space (parapharyngeal/retropharyngeal).

Step 3 management: Recognition triggers a parallel pathway — secure airway assessment, IV access, IV antibiotics, analgesia, and early ENT consultation for drainage rather than empiric outpatient PO antibiotics, which risks progression to airway compromise or Lemierre syndrome.

Peritonsillar abscess (PTA, "quinsy") is a collection of pus between the palatine tonsil capsule and the superior pharyngeal constrictor muscle — the most common deep neck space infection in children and adolescents.

Typically arises as a complication of acute exudative tonsillitis (often GAS) or as progression from peritonsillar cellulitis; Weber salivary glands in the supratonsillar fossa may also be a nidus.

Microbiology is polymicrobial:

Peak incidence in adolescents and young adults (10–30 years); uncommon under age 5 but can occur.

Risk factors: recent/partially treated pharyngitis, chronic tonsillitis, smoking (in teens), dental infection, immunosuppression, prior PTA.

When to suspect in a child with sore throat:

Most children present 3–5 days after onset of pharyngitis that initially seemed routine; failure of outpatient antibiotics is a classic stem clue.

Presentation Patterns and Key History

— Severe unilateral throat pain radiating to the ipsilateral ear (otalgia via CN IX referred pain) — a high-yield Step 3 history clue

— Odynophagia so severe the child refuses solids and liquids → drooling in younger kids

— Muffled "hot potato" voice — caused by soft palate edema, not laryngeal involvement

— Trismus (interincisor distance <2–3 cm) from inflammation of the medial pterygoid

— Foul breath (halitosis), neck pain or torticollis toward the affected side

— Fever, chills, fatigue, headache

— Stridor, dyspnea, or inability to handle secretions

— Neck swelling crossing midline or extending inferiorly

— Chest pain (mediastinitis), persistent rigors after 48–72 h of antibiotics (Lemierre)

— Immunocompromise, poorly controlled diabetes, recent dental procedure

Key distinction: Peritonsillar cellulitis (phlegmon) presents identically early on but lacks fluctuance and uvular deviation; it responds to IV antibiotics alone, whereas a true abscess requires drainage. Trismus severity and asymmetry on exam help separate them at the bedside before imaging.

Board pearl: A teen with mononucleosis (EBV) who develops worsening unilateral throat pain is at elevated risk for PTA — always re-examine the oropharynx in any "mono" patient who is clinically deteriorating.

Classic prodrome: 2–5 days of worsening pharyngitis, often initially diagnosed as viral URI or streptococcal pharyngitis treated with amoxicillin, then abrupt unilateral worsening.

Cardinal symptoms to elicit:

Red-flag history elements suggesting impending airway or deep-space extension:

Recurrence history is important — prior PTA increases recurrence risk to ~10–15%, influencing the decision for interval tonsillectomy.

Ask about household streptococcal exposure, recent dental work, IV drug use (older adolescents), vaccination status (especially Hib in young children where epiglottitis is in the differential).

Medication history: NSAID use can mask fever and partial antibiotic courses can blunt findings without curing the abscess — a frequent stem trap.

Physical Exam Findings and Airway/Hemodynamic Assessment

— Unilateral bulging of the soft palate and anterior tonsillar pillar, often with overlying erythema

— Uvular deviation away from the affected side (the abscess pushes it across the midline)

— Tonsil displaced medially, anteriorly, and inferiorly

— Exudate on tonsils may or may not be present

— Foul breath; pooling saliva

— Voice quality (muffled vs stridorous), drooling, accessory muscle use, oxygen saturation

— If stridor or respiratory distress → do not examine the throat aggressively; arrange controlled airway with anesthesia/ENT

CCS pearl: On a CCS case, the initial order set is "Vitals, IV access, NPO, IV fluids (NS bolus 20 mL/kg if dry), pulse oximetry, ENT consult, IV antibiotics, IV analgesia/antipyretic, NPO." Advancing the clock should reveal trismus and uvular deviation if you've examined the oropharynx.

Board pearl: Uvular deviation contralateral to the bulging tonsil is the single most specific physical finding; absence of deviation should make you reconsider peritonsillar cellulitis or another diagnosis before committing to drainage.

General appearance: ill-appearing, leaning forward, drooling; if tripod posture, stridor, or toxic appearance, immediately broaden the differential to epiglottitis or retropharyngeal abscess and prioritize airway.

Vital signs: tachycardia, fever 38.5–40°C, mild tachypnea; hypotension is uncommon — if present, consider sepsis, dehydration, or Lemierre with septic emboli.

Oropharyngeal exam — the diagnostic centerpiece:

Trismus assessment: measure interincisor distance — <2 cm strongly suggests PTA and may preclude needle aspiration in clinic.

Neck: tender ipsilateral cervical lymphadenopathy, possible torticollis, palpate for crepitus or fluctuance suggesting deeper space involvement.

Airway evaluation (always first in CCS-style thinking):

Hydration status: capillary refill, mucous membranes, urine output — children with severe odynophagia are frequently dehydrated.

Diagnostic Workup — Initial Labs and Imaging

— CBC with differential — leukocytosis with left shift typical

— BMP — electrolyte derangement from poor PO intake

— CRP — supportive, trends with response to therapy

— Blood cultures — only if toxic-appearing, septic, or immunocompromised

— Throat/abscess culture at time of drainage — guides therapy, especially in recurrent or MRSA-risk patients

— Monospot/EBV serology if lymphadenopathy, splenomegaly, or atypical lymphocytes — 20–30% of teens with PTA have concurrent EBV

— Glucose, HbA1c in adolescents with risk factors

— Severe trismus preventing oropharyngeal exam

— Suspected parapharyngeal or retropharyngeal extension

— Young child (<8 y) unable to cooperate

— Failed needle aspiration or recurrence

— Concern for vascular complication (Lemierre, carotid involvement)

— CT neck with IV contrast — gold standard; shows ring-enhancing hypodensity with rim enhancement and mass effect; defines deep neck space anatomy

— Intraoral ultrasound — increasingly used; radiation-free, bedside, distinguishes abscess from cellulitis, can guide aspiration in cooperative children

— Lateral neck X-ray — useful mainly to exclude retropharyngeal abscess (prevertebral soft tissue widening) or epiglottitis

Board pearl: Intraoral ultrasound is the preferred initial imaging in pediatrics when feasible — comparable sensitivity (~90%) to CT for PTA without radiation, and it can localize the pocket for needle aspiration in real time.

Step 3 management: Order CT only when it will change management — most cooperative adolescents with classic findings should proceed directly to bedside drainage without imaging delay.

PTA is fundamentally a clinical diagnosis in a cooperative older child with classic findings — imaging is not required if the exam is unequivocal and drainage is planned.

Indicated labs (especially before drainage or admission):

Imaging indications (when clinical exam is inadequate or atypical):

Modality of choice:

Diagnostic Workup — Advanced or Confirmatory Studies

— Performed under topical/local anesthesia (lidocaine spray + injection) in cooperative patients

— Aspirate sent for Gram stain, aerobic + anaerobic cultures, and sensitivities

— Sensitivity ~90% when performed by experienced operator; false negatives occur with deep or multiloculated abscesses

— Hypodense fluid collection in peritonsillar space with rim enhancement

— Mass effect on airway and adjacent tonsil

— Evaluates for extension into parapharyngeal, retropharyngeal, or masticator spaces

— Identifies internal jugular vein thrombosis (Lemierre) — look for filling defect with surrounding inflammation

— Routine cultures grow polymicrobial flora; results often don't change empiric therapy unless MRSA or resistant Fusobacterium isolated

— PCR for F. necrophorum in select cases with suspected Lemierre

— Rapid strep and throat culture from contralateral tonsil if concurrent pharyngitis treatment is needed for household contacts

Key distinction: Aspiration of pus = abscess (drainage definitive); aspiration of serous fluid or nothing = cellulitis (treat medically with 48-h reassessment). This single bedside maneuver often replaces imaging in straightforward presentations.

Board pearl: In a teen with PTA and persistent fever, rigors, and pulmonary infiltrates 4–7 days into illness, order CT neck with contrast specifically looking for internal jugular vein thrombus — Lemierre syndrome from Fusobacterium necrophorum is the high-yield complication.

Needle aspiration is both diagnostic and therapeutic — return of frank pus confirms PTA and immediately differentiates it from peritonsillar cellulitis.

CT with IV contrast features confirming PTA:

MRI neck: reserved for suspected vascular involvement, intracranial extension, or osteomyelitis of skull base; better soft tissue resolution but limited by access and need for sedation in young kids.

Flexible nasopharyngolaryngoscopy (by ENT): indicated if airway compromise suspected, supraglottic involvement, or to rule out epiglottitis/supraglottitis in equivocal cases.

Microbiologic considerations:

Risk Stratification and First-Line Management Logic

— Outpatient candidates: cooperative adolescent, no airway compromise, tolerating PO after successful aspiration/I&D, reliable follow-up, no immunocompromise → discharge on PO antibiotics with 24–48 h ENT follow-up

— Inpatient admission: young child (<8), failed PO trial, dehydration, severe trismus, suspected deep-space extension, immunocompromise, social concerns

— ICU: airway compromise, sepsis, suspected Lemierre, mediastinitis

— Needle aspiration — least invasive, performed in ED/clinic, preferred initial approach in cooperative patients

— Incision and drainage (I&D) — small mucosal incision over point of maximal fluctuance with blunt dissection

— Quinsy (immediate) tonsillectomy — definitive; reserved for young/uncooperative children requiring general anesthesia, recurrent PTA, complicated cases, or significant tonsillar hypertrophy

— Older cooperative children/teens: needle aspiration or I&D under local anesthesia

— Young children (<8) or uncooperative: drainage under general anesthesia, often combined with tonsillectomy

Step 3 management: A teen with classic PTA who tolerates bedside needle aspiration, can swallow water afterward, and has reliable family support → discharge home on amoxicillin-clavulanate or clindamycin with ENT follow-up in 24–48 hours. Failure to tolerate PO is the line between outpatient and inpatient care.

CCS pearl: Always order single-dose IV dexamethasone alongside antibiotics and drainage — it shortens symptom duration and is a frequent "missed order" on CCS pediatric ENT cases.

Disposition decision tree drives Step 3 management:

Three accepted drainage modalities — all roughly equivalent efficacy (~90% success):

Choice in pediatrics:

Adjunctive measures: IV hydration, analgesia (acetaminophen + NSAIDs; opioids if severe), antipyretics, single-dose IV dexamethasone (0.6 mg/kg, max 10 mg) — reduces pain, trismus, and time to oral intake.

Reassess at 24 hours: clinical improvement (fever curve, trismus, PO intake) expected; if not improving, re-image or repeat drainage.

Pharmacotherapy — First-Line Antibiotic Regimens

— Ampicillin-sulbactam 50 mg/kg/dose IV q6h (max 3 g/dose) — preferred broad coverage including beta-lactamase producers

— Clindamycin 10–13 mg/kg/dose IV q8h (max 900 mg/dose) — for penicillin allergy or suspected MRSA; covers anaerobes and most GAS (watch local clindamycin resistance, which is rising)

— Ceftriaxone + metronidazole — alternative; ceftriaxone alone misses anaerobes

— Add vancomycin 15 mg/kg/dose IV q6h if MRSA suspected (recurrent abscess, prior MRSA, ill-appearing, local prevalence >10%) or septic

— Amoxicillin-clavulanate 45 mg/kg/day divided BID (max 875 mg BID) × 10–14 days

— Clindamycin 10 mg/kg PO TID (max 600 mg/dose) for penicillin allergy

— Linezolid as alternative for resistant organisms

— Dexamethasone single dose 0.6 mg/kg IV/IM (max 10 mg) — reduces pain and trismus

— Acetaminophen 15 mg/kg q4–6h, ibuprofen 10 mg/kg q6h

— Short course opioid (oxycodone 0.1 mg/kg) if severe; avoid prolonged use

— Saline gargles, lozenges (older children), maintenance hydration

Board pearl: Stems mentioning persistent fever and worsening despite 48–72 h of ampicillin-sulbactam should trigger broadening to include MRSA coverage (add vancomycin or switch to linezolid) and re-imaging for inadequate drainage or deep-space extension.

Step 3 management: Document type of penicillin reaction before reflexively choosing clindamycin — a non-severe rash to amoxicillin does not preclude cefuroxime or amoxicillin-clavulanate; severe IgE-mediated reactions or SJS mandate alternative class.

Empiric coverage must include: GAS, oral anaerobes (Fusobacterium, Prevotella), and increasingly MRSA in high-prevalence regions.

Inpatient IV regimens (first-line):

Outpatient PO regimens (after drainage and clinical improvement):

Duration: total course 10–14 days counting IV + PO; transition to PO when afebrile ≥24 h, tolerating oral intake, and clinically improving.

Adjuncts:

Avoid: macrolides alone (high GAS resistance, no anaerobic coverage), narrow-spectrum penicillin V (misses beta-lactamase producers).

Procedures — Drainage Techniques and Tonsillectomy Indications

— Position upright; topical anesthetic (benzocaine or lidocaine spray) + lidocaine 1% with epinephrine injection at puncture site

— 18-gauge spinal needle with plastic needle guard (cut syringe cap) to prevent deep penetration — carotid artery lies ~2.5 cm posterolateral to the tonsil

— Aspirate at point of maximal fluctuance, usually superior pole; if dry, attempt middle then inferior pole

— Send aspirate for Gram stain and culture

— #11 or #15 blade with guard exposing only 1 cm of tip; vertical stab over point of maximal fluctuance

— Blunt dissection with hemostat to break loculations

— Allows continued drainage and is preferred if abscess is large or multiloculated

— Indications: recurrent PTA, age <8 (cooperation), failure of needle aspiration/I&D, complicated PTA with deep-space extension, significant chronic tonsillar disease

— Provides definitive treatment and eliminates recurrence

— Considered after 2nd PTA or after first PTA with history of recurrent tonsillitis (Paradise criteria: ≥7 episodes/year, 5/year × 2 y, or 3/year × 3 y)

— Bleeding (carotid injury rare but catastrophic)

— Aspiration of pus → maintain suction ready, head-down positioning if pus released

— Inadequate drainage → repeat in 24 h or escalate to OR

CCS pearl: On CCS, ordering "ENT consult" in a pediatric PTA case is essential — drainage is rarely physician-of-record territory. Pair it with IV antibiotics, IV fluids, dexamethasone, analgesia, and NPO to maximize order-set credit before drainage occurs.

Board pearl: Needle guard depth limited to ~1 cm is the safety pearl — the internal carotid artery sits posterolateral and slightly deep; uncontrolled deep needle insertion is the source of rare but lethal hemorrhage.

Needle aspiration (preferred initial in cooperative children/teens):

Incision and drainage:

Quinsy tonsillectomy (immediate tonsillectomy at presentation):

Interval tonsillectomy (4–6 weeks after acute resolution):

Procedural complications to anticipate:

Special Populations — Immunocompromised and Comorbid Patients

— Lower threshold for CT imaging, broader empiric antibiotics (add antipseudomonal coverage — piperacillin-tazobactam or cefepime + metronidazole; add antifungal if neutropenic and persistent fever)

— Admit all; never manage outpatient

— Consider atypical pathogens: Candida, Aspergillus, mycobacteria

— Lower threshold for surgical drainage rather than needle aspiration

— Higher rates of polymicrobial and resistant infections, including MRSA and Klebsiella

— Monitor glucose, expect insulin requirements to rise during sepsis

— Aggressive drainage; consider extended IV antibiotic course

— Avoid amoxicillin/ampicillin — causes morbilliform rash in 80–90% of EBV patients

— Use clindamycin or cefuroxime instead

— Concern for splenic rupture with vigorous exam or contact sports → counsel

Key distinction: A teen with PTA, splenomegaly, and exudative pharyngitis = check Monospot/EBV before prescribing amoxicillin — the resulting rash is a classic Step 3 distractor and patient-safety teaching point.

Step 3 management: In a febrile neutropenic child (ANC <500) with PTA, escalate to piperacillin-tazobactam plus vancomycin, admit to a unit capable of close monitoring, and obtain CT neck regardless of exam clarity — early deep-space extension is common and clinical signs are blunted.

Although classic Step 3 "elderly/renal/hepatic" framing applies less to pediatric PTA, analogous special-risk pediatric populations drive management modifications.

Immunocompromised children (leukemia, post-transplant, primary immunodeficiency, chronic steroids, neutropenia):

Diabetes mellitus (adolescents with T1DM or T2DM):

Renal impairment: dose-adjust ampicillin-sulbactam, vancomycin (target trough or AUC monitoring); clindamycin and metronidazole need no adjustment.

Hepatic impairment: avoid prolonged high-dose acetaminophen; clindamycin and metronidazole undergo hepatic metabolism — use cautiously.

EBV/mononucleosis co-infection:

Bleeding diatheses (von Willebrand disease, hemophilia, anticoagulation): coordinate with hematology before drainage; factor replacement or DDAVP as indicated.

Special Populations — Young Children and Recurrence

— PTA is less common but more dangerous due to smaller airway caliber and inability to cooperate with awake drainage

— General anesthesia typically required for drainage; many centers proceed directly to quinsy tonsillectomy to avoid repeated sedations

— Lower threshold for inpatient admission and imaging

— Always reconsider retropharyngeal abscess in this age group — RPA is the more common deep neck infection under age 5

— Recurrence rate after single episode managed with drainage + antibiotics: 10–15%

— Risk factors: chronic tonsillitis history, smoking exposure, immunocompromise, anatomic crypts

— Indications for interval tonsillectomy:

— ≥2 episodes of PTA

— First PTA + Paradise criteria for recurrent tonsillitis

— First PTA + significant chronic tonsillar disease or sleep-disordered breathing

— Timing: 4–6 weeks after acute resolution when tissue inflammation has subsided

— Drainage safe in any trimester; favor local anesthesia when possible

— Antibiotics: amoxicillin-clavulanate (category B equivalent), avoid tetracyclines/fluoroquinolones

— Clindamycin acceptable; metronidazole acceptable after first trimester (controversial in first)

— Imaging: prefer ultrasound; CT only if clearly indicated, shielding abdomen

Board pearl: A 4-year-old with neck stiffness, drooling, and "duck quack" voice — think retropharyngeal abscess (lateral neck X-ray shows widened prevertebral soft tissue); PTA in this age group is less common and presentation overlaps significantly.

CCS pearl: For preschool-age PTA, the high-yield CCS order is "ENT consult, OR for drainage under general anesthesia, IV ampicillin-sulbactam, IV dexamethasone, IV fluids, NPO, continuous pulse oximetry" rather than bedside aspiration.

Children under 8 years:

Recurrent PTA:

Pregnant adolescents:

Adolescent athletes: with concurrent EBV, avoid contact sports for 3–4 weeks due to splenic rupture risk; document return-to-play counseling.

Complications and Adverse Outcomes

— Edema, abscess rupture into airway with aspiration of pus

— Trismus complicates intubation → anesthesia/ENT for awake fiberoptic or surgical airway readiness

— May relieve pain but causes aspiration pneumonia or lung abscess

— Position patient head-down with suction ready during drainage

— Parapharyngeal space → carotid sheath involvement

— Retropharyngeal space → "danger space" → mediastinitis (mortality 20–40%)

— Masticator space → trismus, mandibular involvement

— Classically caused by Fusobacterium necrophorum

— Presents with persistent fever, rigors, neck pain/swelling, pulmonary septic emboli (cavitary lung lesions) 4–10 days into illness

— Diagnosis: CT neck with contrast showing IJ filling defect

— Treatment: prolonged IV antibiotics (β-lactam/β-lactamase inhibitor ± metronidazole) × 3–6 weeks; anticoagulation controversial

Board pearl: Persistent spiking fevers, rigors, and pulmonary infiltrates in a recently diagnosed teen with PTA = Lemierre syndrome until proven otherwise; order CT neck with contrast looking for internal jugular vein thrombus plus blood cultures (Fusobacterium grows slowly — alert lab to hold cultures longer).

Key distinction: Trismus that worsens after drainage, especially with neck swelling crossing midline, signals parapharyngeal extension — re-image and re-drain in OR rather than continuing observation.

Airway compromise — leading immediate threat:

Spontaneous abscess rupture:

Spread to adjacent deep neck spaces:

Lemierre syndrome (septic thrombophlebitis of internal jugular vein):

Carotid artery erosion/pseudoaneurysm: rare but catastrophic; "sentinel bleed" from mouth/ear precedes major hemorrhage

Necrotizing fasciitis of neck (especially diabetics, immunocompromised)

Mediastinitis, empyema, pericarditis from descending infection

Cavernous sinus thrombosis, meningitis, brain abscess from intracranial extension

Sepsis and toxic shock syndrome (especially streptococcal)

Procedure-related: hemorrhage from drainage, dental injury, dysgeusia, post-tonsillectomy bleed (primary <24 h, secondary 5–10 days)

When to Escalate Care — ICU, Consult, and Inpatient Triage

— Stridor, drooling, or any sign of impending airway loss

— Severe trismus (<2 cm interincisor) requiring OR for drainage

— Young child requiring general anesthesia

— Airway compromise (stridor, accessory muscle use, hypoxia)

— Sepsis with hemodynamic instability

— Suspected Lemierre or mediastinitis

— Post-drainage with concern for ongoing bleeding or aspiration

— Immunocompromised with rapidly progressive infection

— Inability to tolerate PO after drainage

— IV antibiotic requirement

— Dehydration requiring IV fluids

— Young children post-drainage

— Social concerns or unreliable follow-up

— Successful bedside drainage with relief of symptoms

— Tolerates PO fluids in ED for 1–2 hours

— Stable vital signs, no airway concern, no immunocompromise

— Caregiver reliable, ENT follow-up arranged within 24–48 hours

— Written return precautions provided

— Infectious disease for recurrent, resistant, or immunocompromised cases

— Interventional radiology for image-guided drainage of deep-space extensions

— Hematology for bleeding disorders before drainage

— Cardiothoracic surgery for descending mediastinitis

CCS pearl: The CCS sequence for severe pediatric PTA with airway concern: "Anesthesia consult, ENT consult, PICU admission, NPO, IV access ×2, continuous pulse oximetry and cardiac monitoring, IV ampicillin-sulbactam, IV dexamethasone, IV fluids, head-of-bed elevation, do not attempt awake intubation."

Step 3 management: Document a clear airway plan before any sedation in a child with trismus — "difficult airway" should be flagged, and the proceduralist (ENT) should be at bedside before induction.

Immediate ENT consultation for every confirmed or strongly suspected PTA — drainage is rarely deferred to general pediatrics or emergency medicine alone.

Anesthesia consultation when:

PICU admission criteria:

Standard pediatric ward admission:

Outpatient management (ED discharge) appropriate when:

Subspecialty involvement:

Key Differentials — Same-Category (Pharyngeal/Tonsillar) Causes

— Diffuse peritonsillar inflammation without discrete fluid collection

— Similar symptoms but no uvular deviation, no fluctuance, less trismus

— Negative needle aspiration (or serous fluid only)

— Treat with IV antibiotics alone × 24 h, reassess — if no improvement, repeat exam/aspirate

— Bilateral exudates, fever, anterior cervical adenopathy

— No trismus, no muffled voice, no uvular deviation

— Centor criteria, rapid strep antigen, throat culture

— Bilateral massive tonsillar enlargement with "kissing tonsils," palatal petechiae, posterior cervical lymphadenopathy, splenomegaly, fatigue

— Monospot/EBV serology positive; atypical lymphocytes

— Can be complicated by superimposed PTA

— Toxic appearance, tripod position, drooling, stridor — no oropharyngeal abnormality on direct exam

— Lateral neck X-ray: "thumb sign"

— Airway emergency

Key distinction: Peritonsillar cellulitis vs abscess — both have unilateral throat pain and tonsillar erythema, but only abscess has uvular deviation, palatal bulge, fluctuance, and yields pus on aspiration. The therapeutic implication (antibiotics alone vs drainage) is the high-yield Step 3 point.

Board pearl: A teen with "kissing tonsils," palatal petechiae, posterior cervical lymphadenopathy, and splenomegaly → think EBV, not PTA — and if you've already given amoxicillin, expect a morbilliform rash on day 7–10.

Peritonsillar cellulitis (phlegmon):

Severe streptococcal pharyngitis/tonsillitis:

Infectious mononucleosis (EBV):

Tonsillolith with surrounding inflammation: chronic halitosis, sensation of foreign body, visible white concretion in tonsillar crypt

Acute supraglottitis/epiglottitis (Hib unvaccinated):

Acute viral pharyngitis (adenovirus, coxsackie, HSV): bilateral, vesicular or exudative, systemic viral features

Herpangina, hand-foot-mouth disease: vesicular lesions, often posterior pharynx, younger children

Lingual tonsillitis: pain on tongue protrusion, normal palatine tonsils

Key Differentials — Other-Category (Deep Neck and Systemic) Causes

— Peak age 2–4 years (suppuration of retropharyngeal lymph nodes)

— Fever, neck stiffness, refusal to move neck, drooling, stridor, "duck quack" voice

— Lateral neck X-ray: prevertebral soft tissue >7 mm at C2 or >14 mm at C6 (or >half the vertebral body width)

— CT neck with contrast confirms; surgical drainage typically required

— Risk: extension to danger space → mediastinitis

— Lateral neck swelling, trismus, medial displacement of tonsil without peritonsillar bulge

— Higher risk of carotid sheath involvement and Lemierre

— CT essential

— Bilateral submandibular space cellulitis, often odontogenic

— Brawny floor-of-mouth induration, tongue elevation, drooling, airway compromise

— Surgical emergency

Board pearl: Persistent painless tonsillar asymmetry in a child without acute inflammation → image and biopsy to rule out lymphoma; this is a Step 3 trap when the stem describes "no fever, gradual enlargement, weight loss, night sweats."

Key distinction: PTA = anterior bulge, uvular deviation. Parapharyngeal abscess = lateral neck swelling, medial tonsil displacement without anterior bulge. Retropharyngeal abscess = neck stiffness, prevertebral widening on X-ray, young child. Anatomic localization drives drainage approach.

Retropharyngeal abscess (RPA):

Parapharyngeal abscess:

Ludwig angina:

Cervical lymphadenitis/suppurative adenitis: tender enlarged node, often Staph/Strep; ultrasound differentiates abscess from reactive node

Diphtheria (rare, unvaccinated travelers): grey pseudomembrane, bull neck, myocarditis

Lemierre syndrome: discussed in complications — also a freestanding consideration in any deteriorating teen with pharyngitis

Pharyngeal foreign body or trauma: history-dependent; consider in younger children with sudden refusal to swallow

Malignancy (rare in pediatrics): lymphoma presenting as tonsillar asymmetry without acute inflammation — chronic painless enlargement, B symptoms

Kawasaki disease: fever ≥5 days, conjunctivitis, rash, mucositis, extremity changes, cervical lymphadenopathy — not localized abscess

Secondary Prevention and Discharge Planning

— Successful drainage with symptom relief

— Tolerating oral fluids and soft diet

— Afebrile or improving fever curve

— Pain controlled on PO analgesics

— Reliable caregiver and follow-up arranged

— Amoxicillin-clavulanate 45 mg/kg/day divided BID × 10–14 days total (count IV days)

— Alternative: clindamycin 10 mg/kg PO TID

— Scheduled acetaminophen + ibuprofen for first 48–72 h

— Short course oral opioid (oxycodone) if severe — limited quantity, counsel on safe disposal

— Magic mouthwash (viscous lidocaine/diphenhydramine/antacid) for symptomatic relief — avoid in young children due to lidocaine toxicity risk

— Worsening pain, fever >48 h, neck swelling, difficulty breathing or swallowing, drooling, persistent bleeding from drainage site

— Lemierre warning signs: persistent rigors, chest pain, hemoptysis

— Smoking cessation counseling (adolescents and household members)

— Dental hygiene optimization, address caries

— Identify and treat chronic tonsillitis to prevent recurrence

— Interval tonsillectomy at 4–6 weeks if recurrence criteria met

Step 3 management: Schedule ENT follow-up at 24–48 h, then again at 2 weeks post-drainage; primary care follow-up at 1 week to confirm clinical resolution, medication adherence, and discuss tonsillectomy candidacy if this is a recurrence.

Board pearl: Two episodes of PTA = referral for tonsillectomy, regardless of underlying tonsillitis history — the Step 3 trigger for definitive surgical management.

Discharge criteria after PTA:

Discharge medications:

Hydration and nutrition: cold liquids, popsicles, soft cool foods; avoid acidic/spicy/hot

Return precautions — written, in caregiver's primary language:

Secondary prevention strategies:

Vaccination review: ensure Hib, pneumococcal, influenza, COVID-19 vaccinations up to date — particularly relevant when epiglottitis was on the differential

Household contact management: if GAS isolated and household has multiple cases, consider treating symptomatic contacts per GAS guidelines

Follow-Up, Monitoring, and Rehabilitation/Counseling

— 24–48 hours: ENT or ED recheck — confirm clinical improvement, no abscess re-accumulation, tolerating PO

— 1 week: primary care — symptom resolution, medication compliance, school return

— 2–4 weeks: ENT — assess for residual symptoms, tonsillar appearance, recurrence risk

— 6 weeks: surgical planning visit if interval tonsillectomy indicated

— Clinical: fever curve, oral intake, pain trajectory, trismus resolution

— Laboratory (only if complicated): CRP trend, CBC, blood cultures if persistent fever

— Imaging: not routine; repeat CT only for clinical deterioration or suspected complication

— Resume school when afebrile 24 h and tolerating regular diet

— Avoid contact sports for 1 week post-drainage; longer (3–4 weeks) if EBV-related splenomegaly

— Wind/brass instruments and vigorous singing — avoid 1 week

— Complete antibiotic course even after symptom resolution

— Recognize recurrence: unilateral worsening sore throat with fever

— Lemierre warning signs in the weeks following

— Smoking cessation (active and passive)

— Hydration and oral hygiene

— Risks: bleeding (primary <24 h, secondary 5–10 days, ~3% rate), anesthesia, dehydration

— Benefits: definitive prevention of recurrent PTA

— Recovery: 10–14 days, pain management with acetaminophen + opioid (avoid ibuprofen post-op per some protocols — controversial; recent evidence supports ibuprofen safety)

CCS pearl: On CCS, after discharge, advance the clock and place follow-up orders — "Schedule ENT follow-up in 48 hours, primary care in 1 week, counsel on return precautions, smoking cessation, complete antibiotic course" — Step 3 grades longitudinal management.

Board pearl: Post-tonsillectomy bleeding presenting 5–10 days post-op (secondary hemorrhage) is the classic stem — manage with rapid airway assessment, IV access, type and crossmatch, ENT for OR control.

Follow-up schedule (Step 3 longitudinal thinking):

Monitoring parameters:

Return to school/activity:

Counseling points:

Tonsillectomy counseling (if recurrence):

Pain expectations: oral pain typically peaks day 3–5 post-drainage, then steadily improves; persistent or worsening pain after day 5 warrants re-evaluation.

Ethical, Legal, and Patient Safety Considerations

— Parental/guardian consent required for procedures in children

— Assent from developmentally capable children (typically ≥7 years) should be obtained and documented

— Discuss risks (bleeding, carotid injury, aspiration), benefits, and alternatives (medical management with reassessment, OR drainage)

— Emergency exception: airway compromise allows treatment without delay if guardian unavailable

— In many states, mature minor doctrine allows adolescents to consent to emergency care

— Pregnancy testing in adolescent females before sedation/imaging — discuss confidentiality per state law

— Substance use history elicited confidentially (relevant for sedation planning)

— Suspicious injury patterns, neglect (recurrent untreated infections, missed appointments)

— Document concerns and involve social work; report suspected child abuse/neglect to CPS

— High-risk handoff points: ED → ward, ward → OR, OR → recovery, discharge → home

— Use structured handoff tools (I-PASS, SBAR)

— Medication reconciliation at every transition, especially antibiotic doses, allergies, EBV status

— Written discharge instructions in caregiver's preferred language with teach-back confirmation

— Prescribing amoxicillin to EBV-positive patient → rash (sentinel event opportunity for systems learning)

— Inadequate airway planning before sedation in trismus

— Missed Lemierre due to anchoring on "improving" PTA

— Failure to arrange follow-up → recurrence and complications

— Recognize disparities in access to ENT subspecialty care; advocate for telemedicine follow-up when in-person access is limited

— Insurance and language barriers can delay surgical management — engage social work early

Step 3 management: A non-English-speaking family discharged with a 14-year-old after PTA drainage — ensure certified medical interpreter present for discharge teaching, written instructions in primary language, and teach-back of return precautions. Document interpreter ID number in the chart — a Step 3 patient safety pearl.

Informed consent for drainage in minors:

Adolescent confidentiality and consent:

Mandatory reporting considerations:

Patient safety — transitions of care:

Avoidable errors:

Health equity:

Quality and value: avoid unnecessary CT imaging in straightforward cases; bedside ultrasound and clinical exam reduce radiation and cost.

High-Yield Associations and Rapid-Fire Clinical Facts

Board pearl: Memorize the PTA microbiology dyad (GAS + Fusobacterium) and the EBV–amoxicillin rash association — both appear in nearly every Step 3 PTA-related stem as either the answer or the most common distractor.

Key distinction: Trismus + unilateral bulge = PTA. Neck stiffness + drooling + young child = RPA. Bilateral floor-of-mouth swelling + tongue elevation = Ludwig angina. Toxic + tripod + stridor + no oropharyngeal finding = epiglottitis.

PTA microbiology: GAS most common aerobe; Fusobacterium necrophorum most common anaerobe and the organism behind Lemierre syndrome.

Classic triad: trismus + muffled "hot potato" voice + uvular deviation.

Otalgia in PTA: referred via CN IX (glossopharyngeal nerve).

Most specific exam finding: contralateral uvular deviation with anterior tonsillar pillar bulge.

Trismus mechanism: inflammation of medial pterygoid muscle.

Safety pearl during aspiration: carotid artery lies ~2.5 cm posterolateral — use needle guard limiting depth to 1 cm.

Imaging of choice (pediatrics): intraoral ultrasound; CT with contrast if deep space extension suspected.

Empiric IV antibiotic: ampicillin-sulbactam; add vancomycin if MRSA risk.

Penicillin allergy: clindamycin (covers GAS + anaerobes).

Adjunct: single-dose IV dexamethasone 0.6 mg/kg (max 10 mg).

EBV pitfall: amoxicillin → morbilliform rash in 80–90%.

Lemierre syndrome: persistent fever, rigors, pulmonary septic emboli, IJ vein thrombus on CT.

Recurrence rate: ~10–15% after single episode.

Interval tonsillectomy indication: ≥2 PTAs or 1 PTA + Paradise criteria.

Paradise criteria for tonsillectomy: ≥7 episodes/year × 1 year, 5/year × 2 years, or 3/year × 3 years.

Retropharyngeal abscess age: 2–4 years (PTA: 10–30 years).

Lateral neck X-ray prevertebral soft tissue: >7 mm at C2 or >14 mm at C6 = retropharyngeal abscess.

Ludwig angina: bilateral submandibular space, odontogenic, airway emergency.

Quinsy tonsillectomy: immediate tonsillectomy for severe/recurrent/uncooperative cases.

Splenic rupture risk in EBV: avoid contact sports 3–4 weeks.

Post-tonsillectomy secondary bleed: 5–10 days post-op.

Board Question Stem Patterns

Step 3 management: Stems often test the order of operations (assess airway → drainage → antibiotics → adjuncts → disposition → follow-up). The answer is rarely "order CT" unless exam is inadequate or deep-space extension is suspected.

Stem 1 — Classic PTA: 16-year-old with 4 days of sore throat now with severe unilateral throat pain, muffled voice, trismus, drooling. Exam: bulging left tonsillar pillar, uvula deviated right. Next step? → Needle aspiration with culture + IV ampicillin-sulbactam + dexamethasone, not CT.

Stem 2 — EBV trap: 17-year-old college athlete with sore throat, given amoxicillin for "strep" 5 days ago, now with diffuse maculopapular rash. Exam: bilateral tonsillar enlargement, posterior cervical adenopathy, splenomegaly. Diagnosis? → Infectious mononucleosis, amoxicillin-induced rash. Avoid contact sports.

Stem 3 — Lemierre: 19-year-old treated for PTA 6 days ago now with rigors, neck swelling, pleuritic chest pain, lung nodules on CXR. Next step? → CT neck with contrast looking for internal jugular vein thrombus; treat Fusobacterium necrophorum with prolonged IV beta-lactam/metronidazole.

Stem 4 — Retropharyngeal abscess: 3-year-old with fever, drooling, neck stiffness, refusal to extend neck. Imaging? → Lateral neck X-ray showing widened prevertebral soft tissues; confirm with CT.

Stem 5 — Recurrent PTA: 15-year-old with second episode of drained PTA in 8 months. Next step? → Refer for interval tonsillectomy 4–6 weeks after acute resolution.

Stem 6 — Airway compromise: 10-year-old with PTA developing stridor and tripoding. Next step? → Anesthesia and ENT to OR for definitive airway and drainage, NOT bedside aspiration.

Stem 7 — Penicillin allergy: PTA in patient with anaphylaxis to penicillin. Antibiotic? → Clindamycin (covers GAS + anaerobes).

Stem 8 — Outpatient vs admission: Cooperative 14-year-old with successful needle aspiration, tolerating fluids, reliable parents. Disposition? → Discharge on amoxicillin-clavulanate with ENT follow-up in 24–48 hours.

Stem 9 — Cellulitis vs abscess: Patient with unilateral throat pain but no uvular deviation, no fluctuance, needle aspiration dry. Diagnosis/treatment? → Peritonsillar cellulitis — IV antibiotics × 24 h, reassess.

One-Line Recap

Peritonsillar abscess in pediatrics is a clinical diagnosis (trismus + muffled "hot potato" voice + uvular deviation) requiring prompt drainage by needle aspiration or I&D, empiric coverage of GAS plus oral anaerobes (ampicillin-sulbactam or clindamycin), adjunctive dexamethasone, and ENT follow-up with tonsillectomy referral after a second episode.

Board pearl: The single most testable Step 3 trap is giving amoxicillin to a teen with undiagnosed EBV-related tonsillar enlargement — always reconsider the diagnosis before reflexively treating presumed "PTA" or "strep" in a teen with bilateral kissing tonsils, posterior cervical adenopathy, and splenomegaly; check Monospot first.

Diagnosis: clinical — unilateral palatal/tonsillar bulge with contralateral uvular deviation, trismus, muffled voice, drooling, severe odynophagia; imaging only when exam is inadequate or deep-space extension suspected (CT neck with contrast or intraoral ultrasound).

Treatment: drainage (needle aspiration > I&D > quinsy tonsillectomy depending on age/cooperation) PLUS IV ampicillin-sulbactam (clindamycin if penicillin-allergic or MRSA suspected) PLUS single-dose IV dexamethasone PLUS hydration and analgesia; 10–14 day total antibiotic course.

Complications to never miss: airway compromise, Lemierre syndrome (Fusobacterium-driven internal jugular vein septic thrombophlebitis with pulmonary septic emboli), parapharyngeal/retropharyngeal extension with mediastinitis, carotid erosion, sepsis.

Longitudinal plan: ENT recheck at 24–48 h, primary care at 1 week; interval tonsillectomy 4–6 weeks after a second PTA or when Paradise criteria are met; counsel on smoking cessation, EBV-related splenic precautions if applicable, and Lemierre warning signs.