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Brain Abscess due to Enterococcus avium
Brain Abscess due to Enterococcus avium SRUJANA MOHANTY, MD; BENU DHAWAN, MD; ARTI KAPIL, MD; BIMAL K. DAS, MD; PARITOSH PANDEY, MCH; ADITYA GUPTA, MCH
ABSTRACT: We report the first case of brain abscess due to Enterococcus avium in a 19-year-old man with chronic otitis media since childhood. The patient presented to the emergency department in a comatose condition. Contrast-enhanced brain computed tomography scan showed a hypodense area with ring enhancement in the right temporal lobe and mass effect with subfalcine and transtentorial herniation. Emergency temporal burr hole operation was performed and pus
drained out, but the patient succumbed to his illness. Culture of the aspirated pus yielded growth of grampositive cocci identified as E avium, an infrequent pathogen of human infections. The association of E avium with brain abscess further extends the clinical spectrum of this rare pathogen. KEY INDEXING TERMS: Brain abscess; Enterococcus avium; Antimicrobial susceptibility. [Am J Med Sci 2005;329(3):161–162.]
rain abscess is a focal suppurative process within the brain parenchyma that continues to be one of the most important neurologic emergencies, with a mortality rate of up to 24% and other major sequelae in up to 70% of patients.1 The bacteriology of brain abscess is diverse and usually consists of a complex mixture of aerobes and obligate anaerobes.1,2 Therefore, accurate identification of the species involved is essential to guide appropriate therapy. Brain abscess due to Enterococcus species is rare3,4 and has been reported to be primarily caused by E faecalis. Enterococcus avium, formerly known as group Q streptococcus, is one of the species of the genus Enterococcus.5 It is a rare pathogen in humans, although it is present as part of the normal flora in the gastrointestinal tract of many individuals.5 E avium– induced abscesses in human beings have primarily been restricted to the abdominal cavity and include those of pancreas,6 gall bladder,7 and spleen.8 We report here a fatal case of brain abscess caused by E avium. To our knowledge, this is the first case of E avium brain abscess to be reported in the literature.
B
chronic suppurative otitis media since childhood. He had no history of any congenital or acquired immune deficiencies. His HIV status was not known. On examination, his neurologic status on Glasgow Coma Scale was assessed as E1V1M1. His pupils were fixed and dilated and he was having spontaneous respiration. Examination of ear revealed exudation of fresh pus from the right ear. A contrast-enhanced computed tomography scan of the brain showed a hypodense area with ring enhancement in the right temporal lobe and mass effect with subfalcine and transtentorial herniation (Figure 1). The patient was intubated and shifted to the operation theater. Right temporal emergency burr hole operation was performed and approximately 40 mL of thick, foulsmelling, yellowish pus was aspirated and sent for bacterial culture study. Thereafter, the cavity was irrigated, wound drainage was performed, and parenteral antibiotics (ceftriaxone, amikacin, and metronidazole) were administered to the patient. The patient’s condition did not improve, however, and he died. Culture of the pus aspirate revealed pure growth of E avium, which was identified by conventional biochemical tests.9 The organism was catalase negative, hydrolysed bile-esculin and grew in 6.5% sodium chloride. In carbohydrate utilization tests performed in purple broth9 (brain-heart infusion broth with bromocresol purple as the indicator), the organism fermented arabinose, lactose, mannitol, sorbitol, and sucrose but not raffinose. It did not hydrolyse arginine and did not reduce potassium tellurite. In a standard antimicrobial disk-diffusion test, the organism was susceptible to ampicillin, erythromycin, gentamicin, ciprofloxacin, teicoplanin, and vancomycin.
Case Report
Discussion
A 19-year-old man was admitted to the emergency department in a comatose condition with a history of headache, vomiting, and seizures over the past 2 weeks. The patient was a known to have
Of the 19 species of enterococci identified so far, E faecalis is the most common, being responsible for 85% to 90% of enterococcal infections.9 E faecium is responsible for the remaining 5% to 10% of cases.9 E avium is a rare cause of infection in humans and can be isolated from avian, canine, and human gastrointestinal tracts.5,10 Strains of E avium may carry Lancefield Group D and Group Q carbohydrate antigens. The organism was originally named Streptococcus avium because of its abundance in chicken
From the Department of Microbiology (SM, BD, AK, BKD) and the Department of Neurosurgery (PP, AG), All India Institute of Medical Sciences, New Delhi, India. Submitted April 19, 2004; accepted October 15, 2004. Correspondence: Dr. Aditya Gupta, MCh, Assistant Professor, Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi-29, India (E-mail: [email protected]). THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
161
Brain Abscess due to Enterococcus avium
E avium was also one of the bacterial species associated with this inflammation in the study.16 Strains of E avium are usually susceptible to beta-lactams and aminoglycosides,7,10,15 in contrast to other commonly isolated Enterococcus spp such as E faecalis or E faecium for which antibiotic resistance is commonly encountered. The strain in the present study was also sensitive to the antibiotics, but the patient succumbed to the infection. In summary, the present case may help to redefine the role of E avium in human intracranial infections. The association of E avium with brain abscess further extends the clinical spectrum of this rare pathogen. References
Figure 1. Contrast-enhanced computed tomography image of the brain showing a ring enhancing heterogenous lesion in the right temporal lobe with surrounding edema and significant mass effect.
feces; the current nomenclature was introduced by Collins et al in 1984.11 We searched the MEDLINE in English language literature from 1966 for E avium, Group Q Streptococcus, and intracranial infections. The search revealed only one case of bacterial meningoencephalitis due to E avium.12 Apart from abscesses, the only other cases of E avium–induced human infections include bacteremia,7,13 endocarditis,10 osteomyelitis,14 and infection of a breast prosthesis.15 Most of these cases were confined to immunocompromised patients or those with serious systemic disease. Furthermore, the isolates in many cases were polymicrobial, occurring in conjunction with other, more common pathogens. E avium has thus been considered to be an organism of low virulence. In contrast, the organism in the present case was isolated in pure culture, highlighting its potential pathogenicity. In our patient, chronic ear infection was the predisposing factor for occurrence of the intracranial abscess. Previous studies also indicate that chronic otomastoiditis is the most common predisposing factor for development of brain abscess and that the temporal lobe is the most common site in brain abscesses of otogenic origin.1 In a study on molecular analysis of bacterial flora associated with chronically inflamed maxillary sinuses, different bacterial species were identified, including Streptococcus species, Staphylococcus aureus, Neisseria species, Pseudomonas aeruginosa, and Stenotrophomonas maltophila.16 162
1. Tunkel AR, Wispelwey B, Scheld WM. Brain abscess. In: Mandell GL, Bennett JE, Dolin R, editors. Mandell, Douglas and Bennett’s principles and practice of infectious diseases. 5th ed. Vol. 1. New York (NY): Churchill Livingstone; 2000. pp. 1016 –28. 2. Chaudhry R, Dhawan B, Laxmi BV, et al. The microbial spectrum of brain abscess with special reference to anaerobic bacteria. Br J Neurosurg 1998;12:127–30. 3. Davenport RJ, Gibson R, Mumford CJ, et al. Brain abscess complicating ischemic stroke. Stroke 1995;26:1501–3. 4. Inamasu J, Kagami H, Nakamura Y, et al. Brain abscess developing at the site of preceding intracerebral hemorrhage. Neurol 2002;249:221–3. 5. Nowlan SS, Deibel RH. Group Q streptococci: ecology, serology, physiology and relationship to established. Enterococci J Bacteriol 1967;94:291– 6. 6. Suzuki A, Matsunaga T, Aoki S, et al. A pancreatic abscess 7 years after a pancreatojejunostomy for calcifying chronic pancreatitis. J Gastroenterol 2002;37:1062–7. 7. Verhaegen J, Pattyn P, Hinnekens P, et al. Isolation of Enterococcus avium from bile and blood in a patient with acute cholecystitis. J Infect 1997;35:77– 8. 8. Farnsworth TA. Enterococcus avium splenic abscess: a rare bird. Lancet Infect Dis 2002;2:765. 9. Facklam RR, Teixeira LM. Enterococcus. In: Lollier L, Balows A, Sussman M, editors. Topley & Wilson’s microbiology and microbial infections. 9th ed. New York (NY): Oxford University Press; 1998. pp. 669 – 82. 10. Swaminathan S, Ritter SB. Enterococcus avium endocarditis in an infant with tetralogy of Fallot. Pediatr Cardiol 1999;20:227– 8. 11. Collins MD, Jones D, Farrow JA, et al. Enterococcus avium nom. rev., comb. nov; E. casseliflavus nom. rev., comb. nov; E. durans nom. rev., comb. nov.; E. gallinarum com. nov.; and E. malodoratus sp. nov. Int J Syst Bacteriol 1985;34:220 –3. 12. Fujimoto C, Yazawa S, Matsuoka F, et al. Bacterial meningoencephalitis in patients undergoing chronic hemodialysis: two case reports. Clin Neurol Neurosurg 2002;104:64 – 8. 13. Patel R, Keating MR, Cockerill FR III, et al. Bacteremia due to Enterococcus avium. Clin Infect Dis 1993;17:1006 –11. 14. Cottagnoud P, Rossi M. Enterococcus avium osteomyelitis. Clin Microbiol Infect 1998;4:290. 15. Ablaza VJ, LaTrenta GS. Late infection of a breast prosthesis with Enterococcus avium. Plast Reconstr Surg 1998; 102:227–30. 16. Paju S, Bernstein JM, Haase EM, Scannapieco FA. Molecular analysis of bacterial flora associated with chronically inflamed maxillary sinuses. J Med Microbiol 2003;52:591–7.
March 2005 Volume 329 Number 3
ABSTRACT: We report the first case of brain abscess due to Enterococcus avium in a 19-year-old man with chronic otitis media since childhood. The patient presented to the emergency department in a comatose condition. Contrast-enhanced brain computed tomography scan showed a hypodense area with ring enhancement in the right temporal lobe and mass effect with subfalcine and transtentorial herniation. Emergency temporal burr hole operation was performed and pus
drained out, but the patient succumbed to his illness. Culture of the aspirated pus yielded growth of grampositive cocci identified as E avium, an infrequent pathogen of human infections. The association of E avium with brain abscess further extends the clinical spectrum of this rare pathogen. KEY INDEXING TERMS: Brain abscess; Enterococcus avium; Antimicrobial susceptibility. [Am J Med Sci 2005;329(3):161–162.]
rain abscess is a focal suppurative process within the brain parenchyma that continues to be one of the most important neurologic emergencies, with a mortality rate of up to 24% and other major sequelae in up to 70% of patients.1 The bacteriology of brain abscess is diverse and usually consists of a complex mixture of aerobes and obligate anaerobes.1,2 Therefore, accurate identification of the species involved is essential to guide appropriate therapy. Brain abscess due to Enterococcus species is rare3,4 and has been reported to be primarily caused by E faecalis. Enterococcus avium, formerly known as group Q streptococcus, is one of the species of the genus Enterococcus.5 It is a rare pathogen in humans, although it is present as part of the normal flora in the gastrointestinal tract of many individuals.5 E avium– induced abscesses in human beings have primarily been restricted to the abdominal cavity and include those of pancreas,6 gall bladder,7 and spleen.8 We report here a fatal case of brain abscess caused by E avium. To our knowledge, this is the first case of E avium brain abscess to be reported in the literature.
B
chronic suppurative otitis media since childhood. He had no history of any congenital or acquired immune deficiencies. His HIV status was not known. On examination, his neurologic status on Glasgow Coma Scale was assessed as E1V1M1. His pupils were fixed and dilated and he was having spontaneous respiration. Examination of ear revealed exudation of fresh pus from the right ear. A contrast-enhanced computed tomography scan of the brain showed a hypodense area with ring enhancement in the right temporal lobe and mass effect with subfalcine and transtentorial herniation (Figure 1). The patient was intubated and shifted to the operation theater. Right temporal emergency burr hole operation was performed and approximately 40 mL of thick, foulsmelling, yellowish pus was aspirated and sent for bacterial culture study. Thereafter, the cavity was irrigated, wound drainage was performed, and parenteral antibiotics (ceftriaxone, amikacin, and metronidazole) were administered to the patient. The patient’s condition did not improve, however, and he died. Culture of the pus aspirate revealed pure growth of E avium, which was identified by conventional biochemical tests.9 The organism was catalase negative, hydrolysed bile-esculin and grew in 6.5% sodium chloride. In carbohydrate utilization tests performed in purple broth9 (brain-heart infusion broth with bromocresol purple as the indicator), the organism fermented arabinose, lactose, mannitol, sorbitol, and sucrose but not raffinose. It did not hydrolyse arginine and did not reduce potassium tellurite. In a standard antimicrobial disk-diffusion test, the organism was susceptible to ampicillin, erythromycin, gentamicin, ciprofloxacin, teicoplanin, and vancomycin.
Case Report
Discussion
A 19-year-old man was admitted to the emergency department in a comatose condition with a history of headache, vomiting, and seizures over the past 2 weeks. The patient was a known to have
Of the 19 species of enterococci identified so far, E faecalis is the most common, being responsible for 85% to 90% of enterococcal infections.9 E faecium is responsible for the remaining 5% to 10% of cases.9 E avium is a rare cause of infection in humans and can be isolated from avian, canine, and human gastrointestinal tracts.5,10 Strains of E avium may carry Lancefield Group D and Group Q carbohydrate antigens. The organism was originally named Streptococcus avium because of its abundance in chicken
From the Department of Microbiology (SM, BD, AK, BKD) and the Department of Neurosurgery (PP, AG), All India Institute of Medical Sciences, New Delhi, India. Submitted April 19, 2004; accepted October 15, 2004. Correspondence: Dr. Aditya Gupta, MCh, Assistant Professor, Department of Neurosurgery, All India Institute of Medical Sciences, New Delhi-29, India (E-mail: [email protected]). THE AMERICAN JOURNAL OF THE MEDICAL SCIENCES
161
Brain Abscess due to Enterococcus avium
E avium was also one of the bacterial species associated with this inflammation in the study.16 Strains of E avium are usually susceptible to beta-lactams and aminoglycosides,7,10,15 in contrast to other commonly isolated Enterococcus spp such as E faecalis or E faecium for which antibiotic resistance is commonly encountered. The strain in the present study was also sensitive to the antibiotics, but the patient succumbed to the infection. In summary, the present case may help to redefine the role of E avium in human intracranial infections. The association of E avium with brain abscess further extends the clinical spectrum of this rare pathogen. References
Figure 1. Contrast-enhanced computed tomography image of the brain showing a ring enhancing heterogenous lesion in the right temporal lobe with surrounding edema and significant mass effect.
feces; the current nomenclature was introduced by Collins et al in 1984.11 We searched the MEDLINE in English language literature from 1966 for E avium, Group Q Streptococcus, and intracranial infections. The search revealed only one case of bacterial meningoencephalitis due to E avium.12 Apart from abscesses, the only other cases of E avium–induced human infections include bacteremia,7,13 endocarditis,10 osteomyelitis,14 and infection of a breast prosthesis.15 Most of these cases were confined to immunocompromised patients or those with serious systemic disease. Furthermore, the isolates in many cases were polymicrobial, occurring in conjunction with other, more common pathogens. E avium has thus been considered to be an organism of low virulence. In contrast, the organism in the present case was isolated in pure culture, highlighting its potential pathogenicity. In our patient, chronic ear infection was the predisposing factor for occurrence of the intracranial abscess. Previous studies also indicate that chronic otomastoiditis is the most common predisposing factor for development of brain abscess and that the temporal lobe is the most common site in brain abscesses of otogenic origin.1 In a study on molecular analysis of bacterial flora associated with chronically inflamed maxillary sinuses, different bacterial species were identified, including Streptococcus species, Staphylococcus aureus, Neisseria species, Pseudomonas aeruginosa, and Stenotrophomonas maltophila.16 162
1. Tunkel AR, Wispelwey B, Scheld WM. Brain abscess. In: Mandell GL, Bennett JE, Dolin R, editors. Mandell, Douglas and Bennett’s principles and practice of infectious diseases. 5th ed. Vol. 1. New York (NY): Churchill Livingstone; 2000. pp. 1016 –28. 2. Chaudhry R, Dhawan B, Laxmi BV, et al. The microbial spectrum of brain abscess with special reference to anaerobic bacteria. Br J Neurosurg 1998;12:127–30. 3. Davenport RJ, Gibson R, Mumford CJ, et al. Brain abscess complicating ischemic stroke. Stroke 1995;26:1501–3. 4. Inamasu J, Kagami H, Nakamura Y, et al. Brain abscess developing at the site of preceding intracerebral hemorrhage. Neurol 2002;249:221–3. 5. Nowlan SS, Deibel RH. Group Q streptococci: ecology, serology, physiology and relationship to established. Enterococci J Bacteriol 1967;94:291– 6. 6. Suzuki A, Matsunaga T, Aoki S, et al. A pancreatic abscess 7 years after a pancreatojejunostomy for calcifying chronic pancreatitis. J Gastroenterol 2002;37:1062–7. 7. Verhaegen J, Pattyn P, Hinnekens P, et al. Isolation of Enterococcus avium from bile and blood in a patient with acute cholecystitis. J Infect 1997;35:77– 8. 8. Farnsworth TA. Enterococcus avium splenic abscess: a rare bird. Lancet Infect Dis 2002;2:765. 9. Facklam RR, Teixeira LM. Enterococcus. In: Lollier L, Balows A, Sussman M, editors. Topley & Wilson’s microbiology and microbial infections. 9th ed. New York (NY): Oxford University Press; 1998. pp. 669 – 82. 10. Swaminathan S, Ritter SB. Enterococcus avium endocarditis in an infant with tetralogy of Fallot. Pediatr Cardiol 1999;20:227– 8. 11. Collins MD, Jones D, Farrow JA, et al. Enterococcus avium nom. rev., comb. nov; E. casseliflavus nom. rev., comb. nov; E. durans nom. rev., comb. nov.; E. gallinarum com. nov.; and E. malodoratus sp. nov. Int J Syst Bacteriol 1985;34:220 –3. 12. Fujimoto C, Yazawa S, Matsuoka F, et al. Bacterial meningoencephalitis in patients undergoing chronic hemodialysis: two case reports. Clin Neurol Neurosurg 2002;104:64 – 8. 13. Patel R, Keating MR, Cockerill FR III, et al. Bacteremia due to Enterococcus avium. Clin Infect Dis 1993;17:1006 –11. 14. Cottagnoud P, Rossi M. Enterococcus avium osteomyelitis. Clin Microbiol Infect 1998;4:290. 15. Ablaza VJ, LaTrenta GS. Late infection of a breast prosthesis with Enterococcus avium. Plast Reconstr Surg 1998; 102:227–30. 16. Paju S, Bernstein JM, Haase EM, Scannapieco FA. Molecular analysis of bacterial flora associated with chronically inflamed maxillary sinuses. J Med Microbiol 2003;52:591–7.
March 2005 Volume 329 Number 3