A 59‐year‐old woman with a medical history of Crohn's disease and hypertension presented to the emergency room with pain in the left side of her neck that had been progressively worsening for 4 days and high fever. The patient was on immunosuppres‐sant drugs including azathioprine and Remicade. On examination, she had a fever of 104.9°F, pulse of 115, and blood pressure of 148/78 mm Hg. She had induration and erythema of her left posterior neck area with stiffness on flexion. On arrival, the differential diagnosis included cellulitis of the neck or meningitis. She had leukocytosis of 12,500 with 85% neutrophils. A CT scan of the neck done in the emergency room showed prominence of musculature posterolaterally on the left without definite abscess formation. A presumptive diagnosis of pyomyositis was made, and antibiotics were initiated. The next day 2 blood cultures grew methicillin‐sensitive Staphylococcus aureus (MSSA). A 2‐D echocardiogram did not show any vegetations. MRI of the neck showed left erector spinae pyomyositis with osteomyelitis of the left C4 pillar. She was initially treated with intravenous ampicillin‐sulbactam and vancomycin, which was eventually changed to cefazolin after the sensitivity results showing MSSA. Antibiotics were continued for 6 weeks with resolution.
Pyomyositis is a bacterial infection of skeletal muscle. It is more common in tropical countries; however, it has been increasingly seen in temperate climates. Most cases in temperate climates occur in immunocompromised patients, especially HIV infected patients. The most common organism is Staphylococcus aureus. It usually occurs in large skeletal muscles of the legs; however, other muscles can also be involved. MRI is a better imaging study than CT scanning because it is more sensitive to diagnosing early pyomyositis. Patients who have persistent fevers or leukocytosis despite antibiotics may have abscess formation, which requires aspiration and drainage. Initial empiric therapy in immunocompetent patients is cefazolin orvancomycin to cover staphylococcus. In immunocompromised patients, broad‐spectrum antibiotics for gram‐positive, gram‐negative, and anaerobic coverage is given, for example, vancomycin plus gentamycin plus clindamycin. Eventually, the antibiotics should be tailored to the culture and sensitivity results. The duration of antibiotics is usually 4 weeks; however, some patients need longer therapy for resolution. Overall mortality is 4%. Delay in starting antibiotics can lead to fulminant bacteremia, septic shock, septic emboli, and endocarditis.
Hospitalists frequently see immunocompromised patients with cellulitis and bacteremia. It is important to differentiate pyomyositis from cellulitis and to initiate prompt, appropriate antibiotic treatment. As noted in this case, early CT or MRI can help to lead to the diagnosis. No or delayed treatment can lead to poor outcomes and high mortality.
T. Gajjar, None; A. Desai, None.
To cite this abstract:Gajjar T, Desai A. An Unusual Case of Pyomyositis of the Neck. Abstract published at Hospital Medicine 2007, May 23-25, Dallas, Texas Abstract 118. https://www.shmabstracts.com/abstract/an-unusual-case-of-pyomyositis-of-the-neck/. Accessed December 10, 2018.