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688 PART 5: Infectious Disorders

nervous system infections, particularly posterior fossa lesions and • Guldfred LA, Lyhne D, Becker BC. Acute epiglottitis: epidemiol-
demonstration of mycotic aneurysms. Technetium bone scanning, used ogy, clinical presentation, management and outcome. J Laryngol
in combination with gallium- or indium-labeled white blood cells, is Otol. 2008;122(8):818-823.
particularly useful for the diagnosis of cranial or cervical osteomyelitis.
• Kinzer S, Pfeiffer J, Becker S, Ridder GJ. Severe deep neck
THERAPEUTIC CONSIDERATIONS space infections and mediastinitis of odontogenic origin: clini-
cal relevance and implications for diagnosis and treatment. Acta
Although resuscitation and surgical measures are of primary importance Otolaryngol. 2009;129(1):62-70.
in the initial management of these life-threatening infections, appropri- • Laupland KB. Vascular and parameningeal infections of the head
ate antibiotics are essential for a successful outcome. The initial selection and neck. Infect Dis Clin North Am. 2007;21(2):577-590.
of empirical antimicrobial regimens should be guided by knowledge • Reynolds SC, Chow AW. Life-threatening infections of the peri-
of the most likely causative organisms, their predicted antimicrobial pharyngeal and deep fascial spaces of the head and neck. Infect Dis
spectrum, as well as bioavailability and other considerations. Maximum Clin North Am. 2007;21(2):557-576, viii.
doses of systemic antimicrobials should be administered to optimize
penetration of bone and the blood-brain barrier. Therapy should be • Roscoe DL, Hoang L. Microbiologic investigations for head and
continued for 2 to 3 weeks. Intracranial and vascular or bone infections neck infections. Infect Dis Clin North Am. 2007; 21(2):283-304.
may require at least 6 to 8 weeks of intravenous antibiotics. • Sandner A, Borgermann J. Update on necrotizing mediastinitis:
Empirical antimicrobial regimens for head and neck and upper respi- causes, approaches to management, and outcomes. Curr Infect Dis
ratory tract infections are presented in Table 73-2. Recommendations Rep. 2011;13(3):278-286.
for intracranial suppurative complications are discussed in Chap. 61.
Although soft tissue infections of odontogenic origin were almost
universally susceptible to penicillin G in the past, this is no longer the
case due to the prevalence of β-lactamase–producing anaerobes such as REFERENCES
pigmented Prevotella spp, Porphoromonas spp, and Fusobacterium spp. Complete references available online at www.mhprofessional.com/hall
Failure of penicillin therapy for such infections have been well docu-
mented. Thus, combination of a β-lactam and β-lactamase inhibi-
5,35
tor (such as ampicillin-sulbactam or amoxicillin-clavulanate) should
be considered. Penicillin G in combination with metronidazole is an Soft Tissue Infections
alternative. However, metronidazole lacks activity against gram-positive CHAPTER
anaerobic cocci such as Peptostreptococcus and facultative organisms John Conly
such as streptococci and S aureus, thus precluding its use as monother- 74
apy for head and neck infections. Clindamycin is useful as an alternative
in the penicillin allergic patient. Erythromycin and tetracycline are not
recommended because of increasing resistance among some strains of
streptococci and their lack of optimal anaerobic activity. Infections KEY CONTENT
1
arising from the paranasal sinuses or the middle ear should be covered
for aerobic or facultative gram-negative bacilli, such as H influenzae • Soft tissue infections characterized by extensive necrosis of subcu-
and Enterobacteriaceae spp. Ciprofloxacin plus either metronidazole taneous tissue, fascia, or muscle are uncommon, but they require
or clindamycin, or a “respiratory” fluoroquinolone (levofloxacin or prompt recognition and urgent surgical treatment.
moxifloxacin) are recommended. For immunocompromised and criti- • The classic hallmarks of necrotizing soft tissue infections are exten-
cally ill patients, broad-spectrum coverage for aerobic gram-negative sive involvement of the subcutaneous tissues and a relative paucity
rods and S aureus (including methicillin-resistant strains) may be of cutaneous involvement until late in the course of the infection.
required (Table 73-2). The antibiotic regimen must be broad spectrum,
bactericidal, and appropriate in dose and schedule. Ciprofloxacin or a • Rapidly spreading soft tissue infections present acutely with severe
third or fourth generation cephalosporin (eg, cefotaxime, ceftriaxone, systemic toxicity.
ceftizoxime, cefepime), each in combination with metronidazole, is • Successful management of these critically ill patients depends on
recommended. Monotherapy with an extended-spectrum penicillin- prompt diagnosis by clinical and radiologic means.
β-lactamase inhibitor (ie, ampicillin-sulbactam, ticarcillin-clavulanate, • The principles of management include fluid resuscitation, hemo-
or piperacillin-tazobactam), or a carbapenem (imipenem-cilastatin or dynamic stabilization, a broad-spectrum antimicrobial regimen,
meropenem) is an alternative choice. The final selection of antimicrobial and early surgical intervention.
therapy should be guided by culture results and susceptibility data. • Prompt surgery, in which a definitive diagnosis is reached and all
necrotic tissue is debrided, should be considered the mainstay of
treatment.
KEY REFERENCES • The mortality rate is highest when the diagnosis is delayed or ini-
• Armstrong AW, Spooner K, Sanders JW. Lemierre’s Syndrome. tial surgical treatment is limited.
Curr Infect Dis Rep. 2000;2:168-173.
• Boscolo-Rizzo P, Da Mosto MC. Submandibular space infection:
a potentially lethal infection. Int J Infect Dis. 2009; 13(3):327-333.
• Brook I. Antibiotic resistance of oral anaerobic bacteria and their CLASSIFICATION OF SOFT TISSUE INFECTIONS
effect on the management of upper respiratory tract and head and In severe soft tissue infections, the initial cutaneous presentation
neck infections. Semin Respir Infect. 2002;17(3):195-203. often belies the relentless progression of subcutaneous tissue necrosis
• Brook I. The role of anaerobic bacteria in upper respiratory and dissection that lies beneath a normal-appearing skin. Successful
tract and other head and neck infections. Curr Infect Dis Rep. management of these soft tissue infections depends on early recogni-
2007;9(3):208-217. tion, appropriate investigations to establish a specific diagnosis, and
combined surgical and medical intervention. A clear understanding

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