The microbiology of deep neck abscesses is similar because the causing bacteria reflect the host's oropharyngeal flora. Most oro-pharyngeal abscesses are polymicrobial; the average number of isolates is 5 (range 1 to 10).1-5 Predominant anaerobic organisms isolated in peritonsillar, lateral pharyngeal, and retropharyngeal abscesses are Prevotella, Porphyromonas, Fusobacterium and Peptostreptococcus spp.; aerobic organisms are group A beta hemolytic streptococcus ( GABHS or Streptococcus pyogenes), Staphylococcus aureus and Haemophilus influenzae. Anaerobes are isolated from most abscesses whenever appropriate techniques for their cultivation have been employed while GABHS is isolated in only about one-third of cases.1 Elevated antibody levels to Fusobacterium nucleatum and Prevotella intermedia, known oral pathogens was found in children who had peritonsillar abscess or cellulitis, supporting their pathogenic role.6
Efficacy antimicrobial agents include cefoxitin, a carbapenem (i.e., imipenem or meropenem), the combination of a penicillin (i.e., ticarcillin) and a beta-lactamase inhibitor (i.e., clavulanate), or clindamycin.
Sites of Origin
Tonsillar capsule, & space below superior constrictor muscle
Swelling of one tonsil, uvullar displacement; trismus, muffled voice
Spontaneous rupture & aspiration; contiguous spread to pterygomaxillary space
Pharyngitis, dental infection trauma
Between posterior pharynx & prevertebral fascia
Unilateral posterior pharyngeal bulging; neck, hyperextension drooling, respiratory distress
Spontaneous rupture & aspiration; contiguous spread to posterior mediastinum, parapharyngeal space
Antibiotics, drainage; artificial airway
Lateral Pharyngeal Abscess
>8 adolescents, adults
Tonsillitis ottitis media, mastoiditis, parotitis, dental manipulation
Anterior & posterior pharyngomaxillary space
Anterior compartment: swelling of the parotid area; trismus; tonsil prolapse/tonsillar fossa
Posterior compartment: septicemia; minimal pain or trismus
Carotid erosion; airway obstruction; intracranium, lung, contiguous spread to mediastinum; septice
The most common fungi involved in CL are Histoplasma capsulatum, Coccidioides immitis, and Paracoccidioides spp.
Studies that utilized methodologies that were adequate for the recovery of anaerobes demonstrated their importance in CL mostly in association with dental or periodontal disease. 11,12 The predominate anaerobes were Peptostreptococcus spp, Gram-negative bacilli and Fusobacterium spp.
Infections of the thyroid are rare, but potentially life threatening.15 The signs and symptoms of infectious thyroiditis may mimic those of a variety of noninfectious inflammatory conditions.
Agents that are rarely recovered include Klebsiella spp., Haemophilus influenzae, Streptococcus viridans, Salmonella spp., Enterobacteriaceae, Mycobacterium tuberculosis, atypical mycobacteria, Aspergillus spp., Coccidioides immitis, Candida spp., Treponema pallidum, and Echinococcus spp. Viruses associated with subacute thyroiditis are measles, mumps, influenza, enterovirus Epstein-barr, adenovirus, echovirus, and St. Louis encephalitis.
Sialadenitis, an acute infection of the salivary glands can occur in any of the glands. The parotid gland is the salivary gland most commonly affected by inflammation, and most reports of the microbiology of sialadenitis were limited to this condition1. The microbiology of infection of the submandibular and sublingual glands has rarely been reported 2.
Aspirates of pus from acute suppurative sialadenitis, were studied for aerobic and anaerobic bacteria. 17 Bacterial growth was present in a total of 47 specimens, 32 from parotid, 9 from submandibular, and 6 from sublingual glands specimens. A total of 55 isolates, 25 aerobic and 30 anaerobic were recovered from parotid infection; anaerobic bacteria only were recovered in 13 (41%), aerobic or facultative bacteria only in 11 (34 %) and mixed aerobic and anaerobic bacteria were recovered in 8 (25 %). (Table 1) A total of 17 isolates, 8 aerobic and 9 anaerobic were recovered from submandibular gland infection; anaerobic bacteria only were recovered in 3 (33%) specimens, aerobic or facultative bacteria only in 4 (44 %) and mixed aerobic and anaerobic bacteria were recovered in 2 (22 %). A total of 10 isolates, 5 aerobic and 5 anaerobic were recovered from In sublingual gland infection; anaerobic bacteria only were recovered in 2 (33%) specimens, aerobic or facultative bacteria only in 2 (33 %), and mixed aerobic and anaerobic bacteria were recovered in 2 (33 %). The predominate aerobes was S. aureus and H.influenzae and the predominate anaerobes were gram negative bacilli (including pigmented Prevotella and Porphyromonas, and Fusobacterium spp.) and Peptostreptococcus spp. This study highlights the polymicrobial nature and importance of anaerobic bacteria in acute suppurative sialadenitis.
There are two other reports of recovery of anaerobes from infections of other salivary glands. Bock18 described a patient with sublingual gland inflammation and a bad taste in the mouth. Numerous spirochetes and a few fusiform bacilli were seen on smears. Baba, et a 19 obtained a Peptococcus in pure culture from a purulent submaxillary gland infection.
Pigmented Prevotella and Porphyromonas spp. are the most common anaerobic gram negative bacilli found in oral flora and, like Peptostreptococcus species, are frequently isolated from odontogenic orofacial infections.5 The paucity of reports of involvement of such organisms in bacterial infections of the parotid gland probably indicates that anaerobic cultures have not been done, or that inadequate anaerobic transport or culture techniques accounted for failure to recover such organisms.
Acute suppurative parotitis should be differentiated from viral parotitis (mumps), which usually is endemic and produces no pus. Other viruses that can cause parotitis include HIV, enteroviruses, Epstein-Barr-virus, parainfluenza, influenza, cytomegalo virus and lymphocytic choriomeningitis virus. Other noninfectious disorders that may be associated with parotid swelling include collagen-vascular disease, cystic fibrosis, alcoholism, diabetes, gout, uremia, sarcoidosis, ectodermal dysplasia syndromes, familial dysautonomia, sialolithiasis, benign and malignant tumors, metal poisoning drug related disorders. Nonparotid swelling that may stimulate parotitis include lymphoma, lymphangitis, cervical adenitis, external otitis, dental abscess, actinomyces not evolving the parotid, and cysts.
Suppurative parotitis is differentiated from these disorders by the ability to produce purulent material at the orifice of Stensen duct by applying pressure over the gland. Occlusion of the orifice may, however, prevent the expression of pus. Tumors are generally unevenly swollen, and tenderness is variable.
Anaerobic infection of the buccal space (such as Ludwig's angina) not evolving the parotid have to be differentiated from parotitis. Actinomyces may have chronic exudate with sulfur granules and is frequently encountered with dental caries. Elevated white blood cells and sedimentation rate and serum amylase or urine diastase are generally seen in suppurative parotitis.
Roentgenogram may reveal the presence of sialolith, and sialogram may demonstrate destruction of ductules or spherical dilation suggestive of suppurative illness.23 CT-sialography is an important tool in diagnosis of tumors.24
Needle aspiration of the gland may yield the causative organism. If no pus is aspirated, introduction of sterile saline and subsequent aspiration may yield organisms. The aspirates should be cultured for aerobic as well as anaerobic bacteria, fungi, and mycobacteria. Surgical exploration and drainage may be indicated for diagnosis as well as for therapy. If infection is not found, search should be made for noninfectious causes of parotic swelling previously mentioned.
A penicillinase-resistant penicillin or first-generation cephalosporin is generally adequate. However, the pressure of methicillin-resistant staphylococci may mandate the use of vancomycin. Clindamycin, cefoxitin, imipenem, the combination of metronidazole and a macrolyde or a penicillin plus beta-lactamase inhibitor, will provide adequate coverage for anaerobic as well as aerobic bacteria.
Maintenance of good oral hygiene, adequate hydration, and early and proper therapy of bacterial infection of the oropharynx may reduce the occurrence of suppurative parotitis.
Br J Oral Maxillofac Surg;23:128-34. 1985.
Arch Dis Child.;77:359-63. 1997.