| A brain abscess is an infected cavity, filled with pus that forms within the brain tissue. The infecting organism can be fungi, protozoa, or bacteria.
Forty percent of intracranial abscesses are caused by middle ear infection (otitis media) and result from infection of the sinuses (sinusitis) and the mastoid portion of one of the bones of the skull near the ear (mastoiditis) (Ernoehazy). Another 25% of brain abscesses result from an infection originating from another part of the body, such as the lungs, skin, or heart valves (Brook). Of these, lung (pulmonary) and dental infections are common sources. Penetrating head injuries or neurosurgical procedures account for another 10% of infections (Brook). Brain abscess is rare in the general population, but individuals with weakened immune systems (immunocompromised) or have other conditions that interfere with healing are particularly at risk for developing a brain abscess.
Examples of other individuals at risk include diabetics, AIDS- or HIV-infected individuals, individuals on immunosuppressing drugs after organ or tissue transplantation, heroin or alcohol abusers, individuals with artificial (prosthetic) or congenitally damaged heart valves, and those with certain cancers (lymphomas). Also at risk are those individuals who do not seek medical help for infections, thus failing to receive the proper antibiotic therapy.Risk: Men and people over 40 are at increased risk to develop brain abscesses (Brook). Brain abscess may also result from parasitic infection secondary to ingestion of foods in underdeveloped countries. Incidence and Prevalence: In the US, brain abscesses occur in 1 out of 10,000 inpatients; brain abscesses occur with much greater frequency in undeveloped countries (Brook). |
Source: Medical Disability Advisor
| History: The location of the abscess may determine the type of symptoms, including headache, fever, drowsiness, inattention, confusion, nausea, vomiting, stiff neck, visual complaints, and seizures. A history of previous infection in another part of the body is often reported. Abscesses resulting from ear or sinus infections are typically located in the part of the brain nearest the source. Physical exam: Abnormalities observed on physical examination vary depending on the site of the abscess, with specific neurological findings reflecting swelling (edema) around the abscess. Some common findings include low-grade fever, neck stiffness (nuchal rigidity) in about 49% of cases seizures, inability to move the eyes, swelling of the optic nerve seen by looking into the eye with an ophthalmoscope, (papilledema), and visual disturbances (Simon). Changes in mental status can range from minimal to major, with the individual becoming sleepy or comatose. If the infection has spread from another site, evidence of the primary infection may also be present. Tests: Blood tests reveal an elevated white blood cell count (WBC) and increased erythrocyte sedimentation rate (ESR) in up to 60% of individuals with brain abscesses (Ernoehazy). Two or more blood cultures may be helpful in detecting organisms in the blood. CT scan may make a definitive diagnosis, although MRI is generally a more reliable diagnostic tool. Early in the course, abscesses show up as low-density, irregular zones that do not enhance on CT scan when a contrast dye is given. As the disease progresses, the distinctive ring enhancement becomes obvious as the abscess wall thickens. Examination of cerebrospinal fluid can help confirm infection, but lumbar puncture is too risky because the sudden release of pressure within the skull can cause the brain to shift downward, putting pressure on vital structures (cerebral herniation), which can lead to irreversible brain damage and death. Drainage of fluid or pus from the abscess can be guided by CT (stereotactic biopsy). Pus that is drained from the abscess can be examined under the microscope and cultured to identify the causative organism. Skull x-rays and radioisotope bone scan can help identify areas of bone destruction, and MRI is also useful in visualizing the abscess. An EEG demonstrates slowing in the region where the abscess resides, which is characteristic of this disorder but not specific to it. SPECT scan can help rule out other neurological lesions in the brain, such as a tumor. |
Source: Medical Disability Advisor
| Treatment consists of antibiotics to fight the underlying infection within the skull cavity, as well as medications to reduce increased intracranial pressure caused by brain swelling. When the abscess is under 2.5 cm, administration of intravenous antibiotics is usually sufficient to eliminate the infection. However, the neurosurgeon should be notified right away to participate in the decision of whether surgery is needed.
If the abscess is over 2.5 cm or fails to shrink with antibiotic treatment or if the individual's symptoms fail to improve, surgical removal of fluid (aspiration) or drainage of the abscess may be necessary. Other treatments during the acute phase of the problem include assisted breathing (mechanical ventilation) and the administration of intravenous fluids. When intracranial pressure is increased, assisted breathing at a rapid rate (hyperventilation) may help reduce pressure by decreasing brain swelling. Anticonvulsant medications may also be given to help prevent seizures. |
Source: Medical Disability Advisor
| Brain abscesses are medical emergencies that require rapid diagnosis and effective treatment. With early diagnosis and proper treatment, the infection is curable. In younger patients who were without decline in neurological function, without serious neurological sequelae, and without other existing medical problems when the first assessment took place, a good outcome is expected. Since MRI and antibiotic treatment have been developed, 5% to15% of individuals with brain abscess die from the condition (Brook). The death rate is greater than half if there is evidence of brain swelling causing downward displacement of the brain within the skull (herniation) when the individual is first seen by the doctor (Ernoehazy). The death rate is increased if the patient does not have surgery to drain the abscess. Seizures, permanent brain damage, coma, and death can occur without proper treatment. Thirty-three percent of individuals have prolonged neurological problems (Townsend 283). |
Source: Medical Disability Advisor
| Individuals with brain abscess may require a variety of rehabilitation services depending on the location and treatments required.
Physical therapy and occupational therapy may be required for a range of services including general conditioning exercises if the individual is weakened from the treatment required, to positioning and passive stretching if the individual is comatose. Physical therapy may be required for gait and transfer training if the individual's balance and coordination has been affected. Occupational therapy may be necessary to address activities of daily living such as dressing and bathing techniques. If an individual fatigues easily, energy conservation methods may also be taught in occupational therapy.
Speech therapy may be needed to promote clarity in speech, swallowing ability, and the understanding of speech if the areas of the brain that control these activities were affected.
Respiratory therapy may be required to decrease congestion in the lungs, particularly if an individual is bedridden or comatose for a period of time. Respiratory therapists may perform chest percussion and utilize positioning techniques to promote the drainage of fluid/phlegm from the lungs. Individuals may learn coughing techniques to assist in clearing the lungs of phlegm.
Individuals may require counseling by a psychologist or psychiatrist to help them cope with their illness, particularly if it occurred in conjunction with another chronic disease such as diabetes or HIV/AIDS. |
Source: Medical Disability Advisor
| Seizures and other neurological symptoms, such as paralysis or speech problems, vary depending on the location of the abscess and the effectiveness of treatment. Brain swelling (edema) associated with the abscess or bleeding (hemorrhage) into the abscess may increase pressure inside the skull, forcing the upper brain (cerebrum) downward into the space normally occupied by the lower brain (brainstem). This process is called uncal or tonsillar herniation, and it often results in irreversible coma and death. If the individual remains unconscious (comatose) for an extended period of time, skin breakdown, pressure sores, and loss of joint mobility (contractures) may occur. Rupture of the abscess into the fluid-filled chambers within the brain (ventricles) is usually fatal. Individuals with underlying disease and/or compromised immune systems, such as diabetes, AIDS, or cancer, may be less likely to recover fully from a brain abscess. |
Source: Medical Disability Advisor
| Due to the variable nature of the disease, work restrictions and accommodations require consideration on an individual basis. If physical and/or mental disabilities (such as difficulty walking, speaking, seeing, or hearing, or changes in personality) occur as a result of brain damage attributed to the brain abscess, environmental workplace adaptations may be necessary. Vocational retraining may also be needed. Time off from work to attend physical therapy, counseling, and/or doctors' appointments may be required. |
Source: Medical Disability Advisor
| If an individual fails to recover within the expected maximum duration period, the reader may wish to consider the following questions to better understand the specifics of an individual's medical case. Regarding diagnosis:
- Has individual recently had otitis media, mastoiditis, or sinusitis?
-
Could the infection have spread from the lungs, heart, or skin?
-
Has individual had a dental infection?
-
Is the individual immunocompromised? Or diabetic?
-
Does individual have an artificial heart valve?
-
Is the individual an IV drug or alcohol abuser?
-
Does individual have cancer?
-
Has individual had previous brain surgery?
-
Did neurological findings suggest swelling around the abscess?
-
Is a low-grade fever present? Neck stiffness?
-
Does the individual experience seizures?
-
Does the individual have inability to move the eyes? Other cranial nerve abnormalities? Papilledema? Visual disturbances?
-
Is the patient's mental status altered?
-
Is a primary infection site evident?
-
Were a WBC and sedimentation rate done? Brain x-rays? CT? MRI? Skull x-rays and a bone scan?
-
Was abscess drained? Was a culture and sensitivity done?
-
Were conditions with similar symptoms ruled out?
Regarding treatment:
- Was the abscess diagnosed and treated early?
-
Is individual on antibiotics? Anticonvulsants?
-
Was it necessary for individual to be on a ventilator? Was hyperventilation tried?
Regarding prognosis:
- Is individual participating in a rehabilitation program?
-
Are all the necessary team members involved?
-
Can individual's employer accommodate any necessary restrictions?
-
Does individual have any conditions that could affect ability to recover? Any physical or emotional complications?
|
Source: Medical Disability Advisor
| Brook, Itzhak. "Brain Abscess." eMedicine. Eds. Jeffrey D. Band, et al. 10 Aug. 2004. Medscape. 22 Oct. 2004 <http://emedicine.com/med/topic200.htm>.Ernoehazy, William. "Brain Abscess." eMedicine. Eds. Edward Bessman, et al. 10 Aug. 2004. Medscape. 13 Oct. 2004 <http://emedicine.com/emerg/topic67.htm>. Simon, Roger P. "Parameningeal Infections." Cecil Textbook of Medicine. Eds. Lee Goldman and J. Claude Bennett. 21st ed. Philadelphia: W.B. Saunders, 2000. MD Consult. Elsevier, Inc. 22 Oct. 2004 <http://home.mdconsult.com/das/book/body/294537344/882/513.html>. Townsend, Gregory C. "Brain Abscess and Other Focal Pyogenic Infections." Infectious Diseases. Eds. Jonathan Cohen and William Powderly. 2nd ed. St. Louis: Mosby, Inc., 2003. 279-288. MD Consult. Elsevier, Inc. 16 Dec. 2004 <http://home.mdconsult.com/das/book/body/306806370/1209/70.html#bottom>. |
Source: Medical Disability Advisor
| Feedback |
| Send us comments, suggestions, corrections, or anything you would like us to hear. If you are not logged in, you must
include your email address, in order for us to respond. We cannot, unfortunately, respond to every comment.
If you are seeking medical advice, please contact your physician. Thank you! |
Send this comment to:
Sales
Customer Support
Content Development
|
|
| |
|
|
|
|
|
This publication is designed to provide accurate and authoritative information in
regard to the subject matter covered. It is published with the understanding that
the author, editors, and publisher are not engaged in rendering medical, legal,
accounting or other professional service. If medical, legal, or other expert assistance
is required, the service of a competent professional should be sought. We are unable to respond to requests for advice.
Any Sales inquiries should include an email address or other means of
communication.
|