Bordetella holmesii, an Emerging Cause of Septic Arthritis

Abstract

f Bordetella holmesii is a well-described pathogen in asplenic and immunocompromised patients. Here we report the first two published cases of septic arthritis caused by B. holmesii documented in apparently immunocompetent patients and unaccompanied by bacteremia. CASE REPORTSC ase 1. A 54-year-old woman presented to the hospital with a suspected right prosthetic knee infection. She had a past medical history significant for hypertension, dyslipidemia, and a bilateral knee replacement in 2008 secondary to osteoarthritis, but no history of frequent or unusual infections. She had experienced chronic pain in her right knee since the initial surgery; because of this, she underwent arthroscopy in July 2010 with a debridement of the meniscus, but the pain did not improve. The pain remained stable until November 2010 when she experienced an acute worsening of her right knee pain associated with swelling, an inability to bear weight, and a low-grade fever. There was no history of corticosteroid injections into the joint for symptom control.On initial examination, the patient had a temperature of 37.9°C and was hemodynamically stable. Her right knee was swollen, tender, and very warm, with a limited range of motion. The remainder of her physical examination was noncontributory.Blood work showed a white blood cell (WBC) count of 9.1 ϫ 10 9 /liter, C-reactive protein (CRP) of 327 mg/liter, and erythrocyte sedimentation rate (ESR) of 90 mm/h. The right knee was aspirated under local anesthesia, and the cell count was 26,060 ϫ 10 6 /liter (94% neutrophils); Gram stain of the aspirate did not show organisms, and bacterial culture was negative after 48 h. There was no growth of any organism in blood culture.The patient was started empirically on intravenous (i.v.) cefazolin and was taken to surgery for a first stage patellofemoral revision with prosthesis removal and replacement by a vancomycin and tobramycin cement spacer.The specimen from the initial knee aspirate was first reported as growing a Gram-negative bacillus after 5 days of culture, after the patient had already undergone surgery. There were four small, gray colonies growing on the blood agar plate incubated aerobically in 5% CO 2 at 35°C. The MacConkey, chocolate agar, and anaerobic plates showed no growth. Gram stain of the culture revealed small Gram-negative bacilli and coccobacilli with much variation in size. Oxidase, urease, and catalase tests were negative. The organism was nonmotile in wet prep and semisolid media incubated at 35°C. There was no growth on a triple sugar iron (TSI) slant. A RapID NH panel (Innovative Diagnostics, Atlanta, GA) was set up but was nonreactive. The patient was switched from cefazolin to ceftriaxone pending identification of the Gramnegative bacterium.The isolate was sent to a reference laboratory but could not be definitively identified by biochemical analysis. Sequencing of a 635-nucleotide region of the 16S rRNA gene was undertaken; this alignment was compared to the NCBI (GenBank plus EMBL plus DDBJ plus PDB sequences) datab...

InvasiveBordetella holmesiiinfections

“…holmesii infection has typically been identified from positive blood cultures. While primary bacteremia was the most commonly reported infection, endocarditis, meningitis, septic arthritis, pneumonia, and pericarditis were also reported [5][6][7][8][9][10][11][12]27]. Our first case represents the first reported episode of diskitis associated with B. holmesii (proven by CT-guided biopsy of the disk space).…”

“…Primary bacteremia without a specified source was the most common presentation of invasive disease. Endocarditis, meningitis, septic arthritis, pericarditis, and pleuropulmonary disease with or without bacteremia were also reported (Table I) [6][7][8][9][10][11][12]27]. Despite occasional cases of severe illness, the clinical outcome of invasive disease was favorable with no reported deaths.…”

“…Those authors that reported antimicrobial agent minimum inhibitory concentrations (MICs) consistently demonstrated higher MICs with b-lactams and lower MICs for carbapenems and quinolones [6,7,9,10,[13][14][15][16][17]30]. Three studies reported disk diffusion results for their isolates but conclusions cannot be formulated based on differing methodologies and lack of performance standards [12,18,19].…”

“…We could find only two other cases whereby MAlDI-TOF MS was used to identify B. holmesii. One case reached genus level identification and the other reached species level identification [9,10]. The remainder of the studies applied a variety of chromatographic and molecular techniques (primarily 16S rRNA) for identification.…”

Septic arthritis in immunocompetent and immunosuppressed hosts

“…Among those reported include various Legionella species (e.g., Legionella pneumophila [63], Legionella bozemanae [64], Legionella dumoffii [65]), Sphingomonas paucimobilis [66], and B. cepacia complex [67]. Bordetella holmesii, a well-described pathogen in asplenic and immunocompromised patients, has been reported rarely in immunocompetent patients [68]. Although Cellulosimicrobium cellulans usually causes infection in immunosuppressed patients, there has been a case report of this organism causing septic arthritis after a penetrating injury in an immunocompetent patient [69].…”