MRSA

Suppurative Cervical Lymphadenitis From MRSA

Hitesh Agrawal, MD; Gunjan Dokania, MD;
and Arcia Rosibell, MD

John H. Stroger Jr. Hospital of Cook County, Chicago, Illinois

A 10-month-old boy presented to the emergency department (ED) with a 2-week history of painful right-sided swelling of the neck along with fever as high as 40.5°C. At the onset of illness, the patient had been admitted and treated with amoxicillin for a day, followed by clindamycin for a week; however, the symptoms worsened, and he was was brought to our ED.

On physical examination, a tender 6 × 6-cm area of swelling was noted on the left side of the boy’s neck, with mild overlying erythema (A). Fluctuance was noted in this area, and a bruit was heard on auscultation.

Laboratory studies revealed a white blood cell count of 24,500/µL with 72.4% neutrophils, a hemoglobin concentration of 7.3 g/dL, a C-reactive protein level of 19.8 mg/L, and an erythrocyte sedimentation rate of 97 mm/h. Further questioning revealed that the patient had been scratched on his left thigh by a cat 3 days before the onset of illness.

mrsa

The boy was started on a regimen of intravenous clindamycin and oral azithromycin, but no improvement was seen over the course of a day.

The results of ultrasonography of the neck showed a large, thick-walled, left-sided neck mass with fluid at the center. Under local anesthesia using topical lidocaine-prilocaine cream, aspiration was performed with a 16-gauge needle during which 15 mL of purulent fluid was withdrawn (B). Culture of the fluid was positive for methicillin-resistant Staphylococcus aureus (MRSA) resistant to clindamycin. The boy received a diagnosis of suppurative cervical lymphadenitis.

He was treated with a 10-day course of levofloxacin, and his swelling and other symptoms resolved completely.

Other differential diagnoses considered in this boy’s case included branchial cleft cyst, cat-scratch disease, thyroid mass, infectious mononucleosis, hemangioma, and tubercular cervical lymphadenitis.

Branchial cleft cyst typically occurs anterior to the sternocleidomastoid muscle, whereas this mass was predominantly in the posterior triangle of the left side of neck. Cat-scratch disease is caused by infection with Bartonella henselae bacteria following a scratch from a cat, and it involves the local submandibular and/or preauricular lymph nodes where the scratch occurred. Our patient had been scratched on the left thigh, and the results of a cat-scratch antibody panel were negative.

Thyroid mass was unlikely given the location and the appearance of the mass on ultrasonography. Negative heterophile antibody (Monospot) test and Epstein-Barr virus DNA results ruled out infectious mononucleosis.

Hemangioma was unlikely given the noncompressible nature of the swelling. Negative tuberculin purified protein derivative test results ruled out tuberculosis.

Naseri and colleagues1 recently studied 21,009 pediatric cases of S aureus infection (21.6% of which were with MRSA) of the head and neck in the United States. They reported an alarming increase in the prevalence of MRSA infections, from 11.8% of S aureus infections in 2001 to 28.1% in 2006. Clindamycin resistance was seen in 47% of all the MRSA isolates.

Clindamycin is the most commonly prescribed antibiotic for staphylococcal infections, and pediatric health care providers should be aware of the emerging resistance of S aureus to it2 and should use clindamycin judiciously to prevent further antimicrobial drug resistance. n

References

1. Naseri I, Jerris RC, Sobol SE. Nationwide trends in pediatric Staphylococcus aureus head and neck infections. Arch Otolaryngol Head Neck Surg. 2009;135(1):14-16.

2. Coticchia JM, Getnick GS, Yun RD, Arnold JE. Age-, site-, and time-specific differences in pediatric deep neck abscesses. Arch Otolaryngol Head Neck Surg. 2004;130(2):201-207.