Septic arthritis caused by Chryseobacterium meningosepticum in an elbow joint prosthesis.

Abstract: Chryseobacterium meningosepticum is a Gram-negative bacillus historically associated with meningitis and sepsis in premature neonates. Clinicians should suspect this organism when Gram-negative bacilli are seen on Gram-stain and culture, particularly in immunocompromised patients, and in cases of disrupted host tissue integrity. We report the first case of septic arthritis due to this organism.

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Chryseobacterium meningosepticum, formerly known as Flavobacterium meningosepticum, rarely causes infection in adults. The organism is resistant to multiple antibiotics and is a ubiquitous Gram-negative bacillus historically associated with meningitis and sepsis in premature neonates. (1) This is the first reported case of septic arthritis caused by this pathogen.

Discussion

C. meningosepticum is a water-borne saprophytic bacterium. It is a nonfermenting, nonmotile, Gram-negative aerobic rod not considered part of the normal human flora. It rarely causes infection in the postneonatal immunocompetent host. (2) Strains of this bacterium have infrequently been reported to cause infection among adults, with most cases involving nosocomial outbreaks of pneumonia in intubated patients in the intensive care unit. (3) This organism has been implicated in outbreaks of infection traced to municipal water reservoirs, potable water, (4) and colonization of tap water in a neonatal intensive care unit. (5) C. meningosepticum has a low degree of pathogenicity, infecting only a small percentage of colonized patients.

Surgical treatment for rheumatoid arthritis is recommended for patients in whom medical management has failed. As surgical treatment of the patient with rheumatoid arthritis continues to evolve, disruption of host tissue integrity through instrumentation or internal placement of medical devices can predispose to infections including infection with C. meningosepticum. (4), (6) Some reported cases of infection with this organism after placement of synthetic indwelling biomedical devices include line sepsis from an infected Groshong catheter, (4) sepsis and cholangitis due to biliary stent placement, (4) endocarditis from prosthetic valve involvement, (7) and peritonitis in a patient with a Tenckhoff catheter. (8)

Recent craniofacial surgery and foreign body placement have also been reported as risk factors for C. meningosepticum meningitis in adults. (9) There have been deaths due to C. meningosepticum bacteremia in patients with burn wounds who had a history of first-aid treatment with untreated water. (10)

Bacterial virulence factors responsible for invasive disease have not yet been fully elucidated. In the normal host, this bacterium is cleared rapidly by immune defenses without antibiotic treatment. (4) C. meningosepticum produces a chromosomally mediated noninducible [beta]-lactamase that is inhibited by clavulanic acid. Inconsistencies in sensitivity patterns determined by Kirby-Bauer disk diffusion and broth dilution have been noted in multiple studies. (11) Treatment failures have occurred with antibiotics to which the organism was deemed sensitive by disk diffusion; however, in the absence of clinical response, the original specimen on retesting by serial dilution studies was found to be resistant. (11) Although there are no optimal regimens for serious infections with C. meningosepticum, case series have suggested efficacy of minocycline, rifampicin, trimethoprim-sulfamethoxazole, and fluoroquinolones. (4) C. meningosepticum is usually resistant to most [beta]-lactam antibiotics including carbapenems, aztreonam, aminoglycosides, chloramphenicol, and erythromycin. (12), (13)

Conclusion

C. meningosepticum is an opportunistic pathogen of low virulence that rarely causes serious infections in adults. Clinicians should consider C. meningosepticum infection when Gram-negative bacilli are detected by Gram stain or culture, in immunocompromised patients, especially premature neonates, and when host tissue integrity has been disrupted through instrumentation or internal placement of medical or surgical devices. Culture-negative specimens on initial evaluation should be followed by histopathology to look for atypical organisms in patients believed to be clinically infected. Failure to consider this unusual pathogen in the differential diagnosis may lead to inadequate antibiotic coverage and poor outcomes.

Knowledge may enable you to memorize the whole of Gray's Anatomy and Osler's Principles and Practice of Medicine, but only wisdom can teach you what to do with what you have learned.

--Robertson Davies

From the Department of Internal Medicine, Medical Center of Central Georgia, and the Section of Infectious Diseases, Mercer University School of Medicine, Macon, GA.

Reprint requests to Ritu Kumar, MD, 777 Hemlock Street, Macon, GA 31201. Email: [e-mail]

Accepted May 30, 2002.

Copyright [C] 2004 by The Southern Medical Association 0038-4348/04/9701-0074

References

(1.) Chang Chien HY, Chiu NC, Li WC, et al. Characteristics of neonatal bacterial meningitis in a teaching hospital in Taiwan from 1984-1997. J Microbiol Immunol Infect 2000;33:100-104.

(2.) Sztajnbok J, Troster EJ. Community-acquired Chryseobacterium meningosepticum pneumonia and sepsis in a previously healthy child. J Infect 1998;37:310-312 (letter).

(3.) Pokrywka M, Viazanko K, Medvick J, et al. A Flavobacterium meningosepticum outbreak among intensive care patients. Am J Infect Control 1993;21:139-145.

(4.) Bloch KC, Nadarajah R, Jacobs R. Chryseobacterium meningosepticum: An emerging pathogen among immunocompromised adults--Report of 6 cases and literature review. Medicine (Baltimore) 1997;76:30-41.

(5.) Hoque SN, Graham J, Kaufmann ME, et al. Chryseobacterium (Flavobacterium) meningosepticum outbreak associated with colonization of water taps in a neonatal intensive care unit. J Hosp Infect 2001;47:188-192.

(6.) Liu CE, Wong WW, Yang SP, et al. Flavobacterium meningosepticum bacteremia: An analysis of 16 cases. Zhonghua Yi Xue Za Zhi (Taipei) 1999;62:125-132.

(7.) Sexton DJ, Houk PC, Grantham RN. Successful treatment of prosthetic valve endocarditis due to Flavobacterium meningosepticum. South Med J 1985;78:1267-1268 (letter).

(8.) Marnejon T, Watanakunakorn C. Flavobacterium meningosepticum septicemia and peritonitis complicating CAPD. Clin Nephrol 1992;38:176-177 (letter).

(9.) Chan KH, Chau PY, Wang RY, et al. Meningitis caused by Flavobacterium meningosepticum after transsphenoidal hypophysectomy with recovery. Surg Neurol 1983;20:294-296.

(10.) Kienzle N, Muller M, Pegg S. Chryseobacterium in burn wounds. Burns 2001;27:179-182.

(11.) Johny M, Khuffash FA, Elhag KM. Antimicrobial treatment of Flavobacterium meningosepticum infection. Ann Trop Paediatr 1983;3:125-128.

(12.) Fraser SL, Jorgensen JH. Reappraisal of the antimicrobial susceptibilities of Chryseobacterium and Flavobacterium species and methods for reliable susceptibility testing. Antimicrob Agents Chemother 1997;41:2738-2741.

(13.) Hsueh PR, Teng LJ, Yang PC, et al. Susceptibilities of Chryseobacterium indologenes and Chryseobacterium meningosepticum to cefepime and cefpirome. J Clin Microbiol 1997;35:3323-3324.

RELATED ARTICLE: Key Points

* Chryseobacterium meningosepticum is an unusual cause of infection in adults. This is the first reported case of septic arthritis due to this pathogen.

* C. meningosepticum is resistant to multiple antibiotics and is a ubiquitous Gram-negative bacillus historically associated with meningitis and sepsis in premature neonates.

* Disruption of host tissue integrity through instrumentation or internal placement of medical devices can predispose to infection with C. meningosepticum.

* Inconsistencies in sensitivity patterns determined by Kirby-Bauer disk diffusion and broth dilution have been noted in multiple studies.

* C. meningosepticum is usually resistant to most [beta]-lactam antibiotics. Failure to consider this unusual pathogen in the differential diagnosis may lead to inadequate antibiotic coverage and poor outcome.

RELATED ARTICLE: Case Report

A 60-year-old white man had advanced rheumatoid arthritis, with multiple joint deformities and replacements. At presentation, he had had swelling of the right elbow for 5 weeks. The right elbow joint had been replaced 4 years earlier. The patient denied fever, chills, or night sweats but reported persistent dull aching pain in the right elbow with decreased joint mobility. There was no history of trauma, pain in other joints, or recent weight loss. The remainder of the review of systems was unremarkable.

The patient had no medical history of heart disease, hypertension, diabetes mellitus, or renal or liver disease. His medications included hydrocodone plus acetaminophen and celecoxib. He was allergic to gold and cortisone. Outpatient joint aspiration yielded 4 ml cloudy fluid. Gram stain and aerobic, anaerobic, and fungal cultures of the joint fluid were negative. There was no history of any recent antibiotic use, and no antibiotic use, and no antibiotic therapy was started at the time of joint aspiration. In view of persistent pain and swelling and a high clinical suspicion of infected prosthesis, he was admitted for removal of the joint.

Vital signs at admission were temperature, 98.4[degrees]F (36.8[degrees]C); heart rate, 78 beats/min; respiratory rate, 12 breaths/min; and blood pressure, 140/80 mm Hg. Swelling and tenderness were present over the right elbow, with severe limitation of flexion and extension. There were no overlying skin changes. Physical examination was otherwise unremarkable. Complete blood count, differential counts, and results of renal and liver function tests were normal. At operation, granulation tissue was excised and the joint prosthesis was removed; both were sent for histopathology; Gram stain; aerobic, anaerobic, fungal, and acid-fast bacilli smears; and cultures.

Postoperatively, treatment was empirically started with intravenous vancomycin. Histopathologic examination of right elbow tissue and elbow prosthesis revealed acute and chronic proliferative synovitis with dense fibrous tissue, along with acute inflammatory cells. Tissue culture grew Gram-negative rods that were later identified as Chryseobacterium meningosepticum. Susceptibility testing by the serial microdilution method showed this organism to be sensitive to cephalosporins (ceftriaxone <8 [micro]g/ml, cefepime <8 [micro]g/ml), fluoroquinolones (ciprofloxacin <1 [micro]g/ml, levofloxacin <2 [micro]g/ml), aminoglycosides (amikacin <16 [micro]g/ml, gentamicin <4 [micro]g/ml), carbapenems (imipenem <4 [micro]g/ml), and trimethoprim-sulfamethoxazole (<2/38 [micro]g/ml). It was resistant to aztreonam (>16 [micro]g/ml). Vancomycin therapy was discontinued, and oral ciprofloxacin was given. The postoperative course was uncomplicated and the patient was discharged home to complete 6 weeks of antibiotic therapy.

Ritu Kumar, MD, and Jeffrey L. Stephens, MD