Brain Abscess Workup

  • Author: Itzhak Brook, MD, MSc; Chief Editor: Burke A Cunha, MD   more...
 
Updated: Feb 28, 2012
 

Laboratory Studies

Routine tests

  • CBC count with differential and platelet count
  • Erythrocyte sedimentation rate (ESR; elevated in up to two thirds of patients)
  • Serum C-reactive protein (CRP) or Westergren sedimentation rate
  • Serological tests for some pathogens (eg, serum immunoglobulin G antibodies, CSF polymerase chain reaction [PCR] for Toxoplasma)
  • Blood cultures (at least 2; preferably before antibiotic usage)
  • Moderate leukocytosis is present, and the ESR and CRP level are generally elevated. Serum sodium levels may be low because of inappropriate antidiuretic hormone production. Platelet counts may be high or low.

Cerebrospinal fluid [25]

  • A lumbar puncture is rarely warranted and is contraindicated if increased intracranial pressure is present because of the potential for CNS herniation and death. The results are usually unrewarding, consisting of an elevated protein level, pleocytosis with variable neutrophil count, a normal glucose level, and sterile cultures. A lumbar puncture is mostly of value to rule out other disease processes, especially bacterial meningitis. CT imaging or MRI scanning prior to lumbar puncture is absolutely indicated upon the presence of any focal neurologic finding or papilledema.[26]
  • The white blood cell count is generally high. It reaches 100,000/µL or higher when the abscess ruptures into the ventricle. Many red blood cells are generally observed at that time, and the CSF lactic acid level is then elevated to more than 500 mg.[27]

Abscess aspirate (obtained via stereotactic CT or surgery) [2]

  • Culture aspirates of abscesses for aerobic, anaerobic, and acid-fast organisms and fungi
  • Gram stain, acid-fast stain (for Mycobacterium), modified acid-fast stain (for Nocardia), and special fungal stains (eg, methenamine silver, mucicarmine)
  • Serology anti-anticysticercal antibodies for the diagnosis of neurocysticercosis
  • Histopathological examination of the brain tissue
Next

Imaging Studies

CT scanning has made other tests, such as angiography, ventriculography, pneumoencephalography, and radionuclide brain scanning, almost obsolete. CT is not as sensitive as MRI but is easier to perform.

CT scanning, preferably with contrast administration, provides a rapid means of detecting the size, the number, and the location of abscesses, and it has become the mainstay of diagnosis and follow-up care. This method is used to confirm the diagnosis, to localize the lesion, and to monitor the progression after treatment. However, CT scan results can lag behind clinical findings.[28]

After the injection of a contrast material, CT scans characteristically show the brain abscess as a hypodense center with a peripheral uniform enhancement ring. Rarely, a well-organized abscess wall fails to generate such ring enhancement.

In the earlier cerebritis stages, CT scans show nodular enhancement with areas of low attenuation without enhancement. As the abscess forms, contrast enhancement is observed. After encapsulation, the contrast material cannot help differentiate the clear center and the CT scan is similar in appearance to those obtained during the early cerebritis stage.

See the image below.

CT scan of a brain abscess. CT scan of a brain abscess.

Many authorities consider MRI to be the first diagnostic method in the diagnosis of brain abscess. It allows for accurate diagnosis and excellent follow-up of the lesions because of its superior sensitivity and specificity. Compared with CT scanning, MRI offers a better ability to detect cerebritis, greater contrast between cerebral edema and the brain, and earlier detection of satellite lesions and the spread of inflammation into the ventricles and subarachnoid space.

See the image below.

MRI of a brain abscess. MRI of a brain abscess.

Contrast enhancement with gadolinium diethylenetriaminepentaacetic acid (a paramagnetic agent) helps differentiate the abscess, the enhancement ring, and the cerebral edema around the abscess. T1-weighted images enhance the abscess capsule, and T2-weighted images can demonstrate the edema zone around the abscess.[29]

Diffusion-weighted (magnetic resonance) imaging (DWI) can be used to differentiate between ring-enhancing lesions caused by brain abscess (hypertensive on DWI) from a malignant lesion (hypotensive on DWI).[30]

Susceptibility-weighted phase imaging showed evidence of paramagnetic substances in agreement with the presence of free radicals from phagocytosis in a study of 14 patients with brain abscesses.[31] This technique may provide additional information that is valuable in the characterization of pyogenic brain abscesses.

Since the advent of CT scanning and MRI, the case-fatality rate has decreased by 90%.

Previous
Next

Other Tests

  • ECG occasionally reveals a focus of high voltage with slow activity. It is nonspecific and rarely of value in confirming the diagnosis. This is the least accurate procedure in the diagnostic evaluation.
Previous
Next

Procedures

  • Biopsy of cerebral lesion: Hyphae and type of branching can assist in ion diagnosis of specific fungal infections. In patients with toxoplasmosis, special immunochemical tests can be used to detect the organism or its antigens. A brain-touch technique using immunofluorescence monoclonal antibodies against the organism can also provide rapid diagnosis.
Previous
Next

Staging

The early stage of the infection (first 7-14 d) is called cerebritis and is associated with edema. Necrosis and liquefaction occur after 2-3 weeks, and the lesion becomes gradually surrounded by a fibrotic capsule.[32]

Previous
Proceed to Treatment & Management
 
 
Contributor Information and Disclosures
Author

Itzhak Brook, MD, MSc  Professor, Department of Pediatrics, Georgetown University School of Medicine

Itzhak Brook, MD, MSc is a member of the following medical societies: American Association for the Advancement of Science, American College of Physicians-American Society of Internal Medicine, American Federation for Clinical Research, American Medical Association, American Society for Microbiology, Armed Forces Infectious Diseases Society, Association of Military Surgeons of the US, Infectious Diseases Society of America, International Immunocompromised Host Society, International Society for Infectious Diseases, Medical Society of the District of Columbia, New York Academy of Sciences, Pediatric Infectious Diseases Society, Society for Ear, Nose and Throat Advances in Children, Society for Experimental Biology and Medicine, Society for Pediatric Research, Southern Medical Association, and Surgical Infection Society

Disclosure: Nothing to disclose.

Specialty Editor Board

Jeffrey D Band, MD  Professor of Medicine, Oakland University William Beaumont School of Medicine; Director, Division of Infectious Diseases and International Medicine, Corporate Epidemiologist, William Beaumont Hospital; Clinical Professor of Medicine, Wayne State University School of Medicine

Disclosure: Nothing to disclose.

Francisco Talavera, PharmD, PhD  Adjunct Assistant Professor, University of Nebraska Medical Center College of Pharmacy; Editor-in-Chief, Medscape Drug Reference

Disclosure: Medscape Salary Employment

Ronald A Greenfield, MD  Professor, Department of Internal Medicine, University of Oklahoma College of Medicine

Ronald A Greenfield, MD is a member of the following medical societies: American College of Physicians, American Federation for Medical Research, American Society for Microbiology, Central Society for Clinical Research, Infectious Diseases Society of America, Medical Mycology Society of the Americas, Phi Beta Kappa, Southern Society for Clinical Investigation, and Southwestern Association of Clinical Microbiology

Disclosure: Pfizer Honoraria Speaking and teaching; Gilead Honoraria Speaking and teaching; Ortho McNeil Honoraria Speaking and teaching; Abbott Honoraria Speaking and teaching; Astellas Honoraria Speaking and teaching; Cubist Honoraria Speaking and teaching; Forest Pharmaceuticals Speaking and teaching

Eleftherios Mylonakis, MD  Clinical and Research Fellow, Department of Internal Medicine, Division of Infectious Diseases, Massachusetts General Hospital

Eleftherios Mylonakis, MD is a member of the following medical societies: American Association for the Advancement of Science, American College of Physicians, American Society for Microbiology, and Infectious Diseases Society of America

Disclosure: Nothing to disclose.

Chief Editor

Burke A Cunha, MD  Professor of Medicine, State University of New York School of Medicine at Stony Brook; Chief, Infectious Disease Division, Winthrop-University Hospital

Burke A Cunha, MD is a member of the following medical societies: American College of Chest Physicians, American College of Physicians, and Infectious Diseases Society of America

Disclosure: Nothing to disclose.

References

  1. Levy RM. Brain abscess and subdural empyema. Curr Opin Neurol. Jun 1994;7(3):223-8. [Medline].

  2. Mathisen GE, Johnson JP. Brain abscess. Clin Infect Dis. Oct 1997;25(4):763-79; quiz 780-1. [Medline].

  3. Brook I, Friedman EM. Intracranial complications of sinusitis in children. A sequela of periapical abscess. Ann Otol Rhinol Laryngol. Jan-Feb 1982;91(1 Pt 1):41-3. [Medline].

  4. Glickstein JS, Chandra RK, Thompson JW. Intracranial complications of pediatric sinusitis. Otolaryngol Head Neck Surg. May 2006;134(5):733-6. [Medline].

  5. Brook I. Microbiology and antimicrobial treatment of orbital and intracranial complications of sinusitis in children and their management. Int J Pediatr Otorhinolaryngol. Sep 2009;73(9):1183-6. [Medline].

  6. Migirov L, Duvdevani S, Kronenberg J. Otogenic intracranial complications: a review of 28 cases. Acta Otolaryngol. Aug 2005;125(8):819-22. [Medline].

  7. Carpenter J, Stapleton S, Holliman R. Retrospective analysis of 49 cases of brain abscess and review of the literature. Eur J Clin Microbiol Infect Dis. Jan 2007;26(1):1-11. [Medline].

  8. Singh N, Husain S. Infections of the central nervous system in transplant recipients. Transpl Infect Dis. Sep 2000;2(3):101-11. [Medline].

  9. Tunkel AR, Pradhan SK. Central nervous system infections in injection drug users. Infect Dis Clin North Am. Sep 2002;16(3):589-605. [Medline].

  10. Bensalem MK, Berger JR. HIV and the central nervous system. Compr Ther. Spring 2002;28(1):23-33. [Medline].

  11. Tseng JH, Tseng MY. Brain abscess in 142 patients: factors influencing outcome and mortality. Surg Neurol. Jun 2006;65(6):557-62; discussion 562. [Medline].

  12. Brook I. Brain abscess in children: microbiology and management. J Child Neurol. Jul 1995;10(4):283-8. [Medline].

  13. Brook I. Microbiology of intracranial abscesses and their associated sinusitis. Arch Otolaryngol Head Neck Surg. Nov 2005;131(11):1017-9. [Medline].

  14. Finegold SM. Anaerobic Bacteria in Human Disease. New York, NY: Academic Press; 1977.

  15. Schwartz S, Thiel E. Update on the treatment of cerebral aspergillosis. Ann Hematol. 2004;83 Suppl 1:S42-4. [Medline].

  16. Naesens R, Ronsyn M, Druwe P, et al. Central nervous system invasion by community-acquired meticillin-resistant Staphylococcus aureus. J Med Microbiol. Sep 2009;58(Pt 9):1247-51. [Medline].

  17. Le Moal G, Landron C, Grollier G, et al. Characteristics of brain abscess with isolation of anaerobic bacteria. Scand J Infect Dis. 2003;35(5):318-21. [Medline].

  18. Tsou TP, Lee PI, Lu CY, et al. Microbiology and epidemiology of brain abscess and subdural empyema in a medical center: a 10-year experience. J Microbiol Immunol Infect. Oct 2009;42(5):405-12. [Medline].

  19. Kranick SM, Vinnard C, Kolson DL. Propionibacterium acnes brain abscess appearing 10 years after neurosurgery. Arch Neurol. Jun 2009;66(6):793-5. [Medline].

  20. Goodkin HP, Harper MB, Pomeroy SL. Intracerebral abscess in children: historical trends at Children's Hospital Boston. Pediatrics. Jun 2004;113(6):1765-70. [Medline].

  21. Swartz MN, Karchmer AE. Balow's infections of the central nervous system. In: Anaerobic Bacteria: Role in Disease. Springfield: CC Thomas; 1974:309-25.

  22. Sanchez-Portocarrero J, Perez-Cecilia E, Corral O, et al. The central nervous system and infection by Candida species. Diagn Microbiol Infect Dis. Jul 2000;37(3):169-79. [Medline].

  23. Erdogan E, Beyzadeoglu M, Arpaci F, Celasun B. Cerebellar aspergillosis: case report and literature review. Neurosurgery. Apr 2002;50(4):874-6; discussion 876-7. [Medline].

  24. Al Masalma M, Lonjon M, Richet H, Dufour H, Roche PH, Drancourt M, et al. Metagenomic analysis of brain abscesses identifies specific bacterial associations. Clin Infect Dis. Jan 2012;54(2):202-10. [Medline].

  25. Bernardini GL. Diagnosis and management of brain abscess and subdural empyema. Curr Neurol Neurosci Rep. Nov 2004;4(6):448-56. [Medline].

  26. Muzumdar D, Jhawar S, Goel A. Brain abscess: an overview. Int J Surg. 2011;9(2):136-44. [Medline].

  27. Brook I. The importance of lactic acid levels in body fluids in the detection of bacterial infections. Rev Infect Dis. May-Jun 1981;3(3):470-8. [Medline].

  28. Nguyen JB, Black BR, Leimkuehler MM, et al. Intracranial pyogenic abscess: imaging diagnosis utilizing recent advances in computed tomography and magnetic resonance imaging. Crit Rev Comput Tomogr. 2004;45(3):181-224. [Medline].

  29. Sener RN. Diffusion MRI findings in neonatal brain abscess. J Neuroradiol. Jan 2004;31(1):69-71. [Medline].

  30. Leuthardt EC, Wippold FJ 2nd, Oswood MC, et al. Diffusion-weighted MR imaging in the preoperative assessment of brain abscesses. Surg Neurol. Dec 2002;58(6):395-402; discussion 402. [Medline].

  31. Lai PH, Chang HC, Chuang TC, Chung HW, Li JY, Weng MJ, et al. Susceptibility-Weighted Imaging in Patients with Pyogenic Brain Abscesses at 1.5T: Characteristics of the Abscess Capsule. AJNR Am J Neuroradiol. Jan 26 2012;[Medline].

  32. Britt RH, Enzmann DR. Clinical stages of human brain abscesses on serial CT scans after contrast infusion. Computerized tomographic, neuropathological, and clinical correlations. J Neurosurg. Dec 1983;59(6):972-89. [Medline].

  33. Yogev R, Bar-Meir M. Management of brain abscesses in children. Pediatr Infect Dis J. Feb 2004;23(2):157-9. [Medline].

  34. Nakajima H, Iwai Y, Yamanaka K, et al. Successful treatment of brainstem abscess with stereotactic aspiration. Surg Neurol. Nov 1999;52(5):445-8. [Medline].

  35. Honda H, Warren DK. Central nervous system infections: meningitis and brain abscess. Infect Dis Clin North Am. Sep 2009;23(3):609-23. [Medline].

  36. Livraghi S, Melancia JP, Antunes JL. The management of brain abscesses. Adv Tech Stand Neurosurg. 2003;28:285-313. [Medline].

  37. Barling RW, Selkon JB. The penetration of antibiotics into cerebrospinal fluid and brain tissue. J Antimicrob Chemother. May 1978;4(3):203-27. [Medline].

  38. Stephanov S. Surgical treatment of brain abscess. Neurosurgery. Apr 1988;22(4):724-30. [Medline].

 
Previous
Next
 
CT scan of a brain abscess.
MRI of a brain abscess.
Brain abscess.
 
 
 
All material on this website is protected by copyright, Copyright © 1994-2012 by WebMD LLC.
This website also contains material copyrighted by 3rd parties.

DISCLAIMER: The content of this Website is not influenced by sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.