An 8-year-old boy is brought to the emergency department due to neck swelling and fever. He first developed left-sided neck swelling 2 days ago. Over the last 24 hours, the area has become significantly larger, and the patient cries if the area is touched. He developed fever this morning but has otherwise been well. Temperature is 38.9 C (102 F). Physical examination shows a red, tender, and fluctuant anterior cervical mass approximately 4 cm in diameter in the left anterior lymph node chain. Incision and drainage are performed, and the patient is admitted to the hospital for intravenous antibiotic therapy. Anaerobic bacteria are cultured from the aspirated purulent fluid. Which of the following risk factors most likely contributed to this patient's condition?
Cervical lymphadenitis in children | ||
Pathogen | Key clinical findings | |
Unilateral | Staphylococcus aureus, Streptococcus pyogenes |
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Anaerobic bacteria (eg, Prevotella spp) |
| |
Francisella tularensis |
| |
Mycobacterium avium |
| |
Bartonella henselae |
| |
Bilateral | Viral |
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CMV = cytomegalovirus; EBV = Epstein-Barr virus; URI = upper respiratory infection. | ||
This patient has acute, unilateral cervical lymphadenitis, an infection characterized by an enlarged, markedly tender, warm, erythematous lymph node. Patients may have fever but are usually not toxic appearing.
Acute, unilateral cervical lymphadenitis is typically due to gram-positive bacteria (eg, Staphylococcus aureus, Streptococcus pyogenes) and occurs in children age <5. However, anaerobic bacteria, which account for most normal oropharyngeal flora, are less common causative pathogens in children age <5 but are often implicated in older children with poor dental hygiene (eg, dental caries) or periodontal disease. Poor oral hygiene allows anaerobic bacteria to spread from the oropharynx into surrounding tissue and locally draining lymph nodes.
The diagnosis of acute, unilateral cervical lymphadenitis is usually clinical. Abscess, which is suggested by fluctuance on examination, may require incision and drainage, as in this patient. Empiric antibiotic therapy targets both gram-positive and anaerobic bacteria (eg, amoxicillin-clavulanate, clindamycin).
(Choice A) Tularemia is an aerobic bacterial infection acquired through contact with an infected animal (eg, rabbit, rodent). Symptoms begin with a nonspecific prodrome (eg, fever, malaise), and examination reveals localized lymphadenopathy near an ulcerative papule, findings not seen in this patient.
(Choice B) Diphtheria is a vaccine-preventable disease caused by the aerobic bacterium Corynebacterium diphtheriae. Patients often have cervical lymphadenopathy but classically have sore throat with an adherent, posterior pharyngeal pseudomembrane, which is not seen in this boy.
(Choice C) Most common viruses (eg, adenovirus) are transmitted via respiratory droplets and cause bilateral lymphadenopathy and upper respiratory symptoms (eg, cough, sore throat). In contrast, anaerobic infection is typically caused by local spread of normal oral flora.
(Choice E) Bartonella henselae, an aerobic, gram-negative bacterium, is transmitted via a cat scratch or bite, causing catscratch disease. Symptoms include subacute or chronic lymphadenitis and a papular skin lesion at the site of injury.
(Choice F) Sporotrichosis is a chronic infection acquired after exposure to soil or moss (eg, during rose gardening) with the fungus Sporothrix schenckii. Symptoms classically include nodular papules or ulcerations at the site of exposure and along the draining lymphatic chain. This patient has acute bacterial lymphadenitis.
Educational objective:
Acute, unilateral cervical lymphadenitis in children typically presents with an erythematous, tender, warm lymph node, as well as possible fever and fluctuance. Anaerobes are often the causative organisms in patients with a history of periodontal disease or dental caries via local spread of bacteria.