title: Head and neck infections caused by Streptococcus milleri group: an analysis of 17 cases.
abstract: BACKGROUND
  Streptococcus milleri group (SMG) is a common inhabitant of the mouth and gastrointestinal tract, and can be an aggressive pathogen causing abscess formation at various sites in the body. However, it has rarely been listed as a cause of head and neck infections.
  
  
  OBJECTIVE
  The present study was performed to evaluate the clinical significance of SMG by reviewing the microbiology and clinical records of patients with SMG in head and neck infections retrospectively.
  
  
  METHODS
  A retrospective review of all patients diagnosed as having SMG bacterial infections at Onomichi General Hospital, Hiroshima, between the years 2001 and 2002 was performed; 17 patients developed head and neck infections with SMG. Here, we describe the clinical features and management of SMG in head and neck infection.
  
  
  RESULTS
  The patient population consisted of 12 males and 5 females with a median age of 62 years (age range, 8-78 years). The sites of infection were as follows: maxillary sinus (n=6), peritonsillar region (n=4), subcutaneous (n=3), submandibular space-retropharyngeal space (n=1), deep neck-mediastinum (n=1), parapharyngeal space (n=1), submandibular space (n=1), tonsil (n=1), parotid gland (n=1), and masseter muscle (n=1). Ten cases (59%) were of suppurative diseases. Six cases (35%) had mixed SMG with anaerobe infection. Three cases showed deteriorating clinical courses, and all three of these cases were culture-positive for SMG with anaerobes. In addition, one deteriorating case showed gas gangrene regardless of repeated surgical debridement and intravenous antibiotic therapy; hyperbaric oxygen therapy improved this patient's condition.
  
  
  CONCLUSIONS
  It is important to recognize SMG as a pathogen in head and neck infection. In addition, the care should be taken with infectious diseases caused by SMG with anaerobes as the patient's clinical course can deteriorate rapidly.
authors.affiliation: Department of Otorhinolaryngology, Head and neck surgery, Hiroshima Prefectural Hospital, 1-5-54 Ujinakanda, Hiroshima 734-8530, Japan. t-hirai@hph.pref.hiroshima.com
authors.forename: Tomohisa
authors.initials: T
authors.lastname: Hirai
authors.forename: Shinji
authors.initials: S
authors.lastname: Kimura
authors.forename: Naoki
authors.initials: N
authors.lastname: Mori
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D006801:Humans; D006931:Hyperbaric Oxygenation / Q000379:methods; D008297:Male; D008443:Maxillary Sinus / Q000382:microbiology; D008477:Mediastinal Diseases / Q000382:microbiology* / Q000628:therapy; D008875:Middle Aged; D010254:Paranasal Sinus Diseases / Q000382:microbiology* / Q000628:therapy; D010305:Parotid Diseases / Q000382:microbiology* / Q000628:therapy; D000039:Peritonsillar Abscess / Q000382:microbiology* / Q000628:therapy; D012189:Retrospective Studies; D013290:Streptococcal Infections / Q000150:complications* / Q000628:therapy; D034364:Streptococcus milleri Group / Q000302:isolation & purification*; D013364:Submandibular Gland Diseases / Q000382:microbiology* / Q000628:therapy