title: Cystic Neutrophilic Granulomatous Mastitis:  Association With Gram-Positive Bacilli and Corynebacterium.
abstract: OBJECTIVE
  To determine whether cystic neutrophilic granulomatous mastitis (CNGM) can be associated with Gram-positive bacilli and Corynebacterium
  
  
  METHODS
  We reviewed our experience with 35 granulomatous mastitis patients over a 10-year period, including histologic pattern, Gram stain and other microbiologic data, clinical presentation, treatment and outcome.
  
  
  RESULTS
  Biopsies from 19 patients demonstrated CNGM, while 16 patients had other patterns of granulomatous mastitis. Gram-positive organisms were seen within microcystic spaces in 16/19 CNGM, but 0/16 non-CNGM patients (P = .000). Culture or molecular studies demonstrated Corynebacterium species in three, all CNGM. Patients with CNGM were more likely to be younger, of Hispanic ethnicity, and born outside of the United States. Granulomatous mastitis resolved after a protracted course with widely variable treatment (antibiotics, surgery, steroids).
  
  
  CONCLUSIONS
  Our data further support CNGM as an infectious disease; further study of Corynebacterium-directed therapy in CNGM is needed.
authors.affiliation: From the Department of Pathology Department of Pathology, Stanford University, Stanford, CA. troxellm@ohsu.edu.
authors.forename: Megan L
authors.initials: ML
authors.lastname: Troxell
authors.affiliation: Department of Surgery.
authors.forename: Nicole T
authors.initials: NT
authors.lastname: Gordon
authors.affiliation: Division of Infectious Diseases, Portland Veterans Affairs Medical Center, Portland, OR.
authors.forename: J Stone
authors.initials: JS
authors.lastname: Doggett
authors.affiliation: Department of Pathology, Stanford University, Stanford, CA.
authors.forename: Morgan
authors.initials: M
authors.lastname: Ballard
authors.affiliation: Department of Surgery, Division of Surgical Oncology, Oregon Health & Science University, Portland.
authors.forename: John T
authors.initials: JT
authors.lastname: Vetto
authors.affiliation: Department of Surgery, Division of Surgical Oncology, Oregon Health & Science University, Portland.
authors.forename: Rodney F
authors.initials: RF
authors.lastname: Pommier
authors.affiliation: Department of Surgery, Division of Surgical Oncology, Oregon Health & Science University, Portland.
authors.forename: Arpana M
authors.initials: AM
authors.lastname: Naik
mesh_terms: D000328:Adult; D000368:Aged; D003354:Corynebacterium Infections / Q000150:complications*; D005260:Female; D016908:Gram-Positive Bacterial Infections / Q000150:complications; D058890:Granulomatous Mastitis / Q000382:microbiology* / Q000473:pathology*; D006801:Humans; D008875:Middle Aged; D055815:Young Adult
keywords: Corynebacterium; Cystic neutrophilic granulomatous mastitis; Gram-positive rods; Granulomatous mastitis; IgG4