What is a brain tumour ?

A brain tumour is a heap of anomalous tissue growing in any part of the brain. For some indefinite reason, some brain cells grow in an uncontrolled manner and develop these tumours. These tumours can occur from any part of the brain, spinal cord or the nerves. Generally these tumours can be separated into benign and malignant tumours.

Benign tumours develops slowly and never reach to other parts. However, as they gradually expand in size they can produce stress the normal brain and disturb mental and bodily functions. A few of the benign tumours known are: meningiomas, pituitary adenoma, craniopharyngioma, epidermoid cysts, neurocytoma, haemangioma, pilocytic astrocytoma, etc.
Malignant tumours or cancers are hostile tumours that develops fast and penetrate into the surrounding brain and at times reach to the other parts of the brain or spine. There are several types of malignant brain tumours similar to High Grade Astrocytoma/Glioma, ependymoma, PNET, medulloblastoma, lymphoma, Germ cell tumours. By insistent and timely therapy some of these can be cured.

Symptoms Commonly Observed:

• Limb weakness and some abnormal feeling in the limbs can be a symptom of a tumour in particular parts of the brain mainly in and around the motor or sensory cortex. Usually the opposite side gets affected i.e right-sided weakness by a tumour in the left motor cortex.
• Wobbly walking or imbalance (ataxia) can occur if the tumour is in the cerebellum or any other part of the brain.
• Eyesight could become unclear or sometimes lost if the optic nerve is squashed or enlarged (Papilloedema).
• Sometimes a squint or dual vision (diplopia) can develop if the nerves moving the eyes be exaggerated.
• Current or long term memory could get faint.
• Speech: Capacity to grasp (sensory aphasia) or express (motor aphasia) could be affected by tumours in particular parts of the brain. At times the person can understand but can not express in proper way and can not get the correct words.
• Distorted behaviour, exhaustion, sleepiness, and loss of consciousness are several other symptoms of brain tumours.

Methods to detect a brain tumour:
The majority symptoms explained above are vague and can be caused by various other diseases. A thorough history and medical investigation is initialy done by the doctor and if a brain tumour is alleged then more tests as CT or MRI scan, angiogram, CSF test, hormonal blood test or EEG can be done.
CT or MRI Scan makes special X-ray films that show the complete structure of the brain and spine and pick up any malformation. To obtain a clearer picture, Iodine or Gadolinium diverge dyes are given intravenously. A number of people can develop an allergic effect to the iodine contrast agent and you must every time tell the doctor if you get any allergies. The extra expensive non-ionic diverge agents diminish the risk of allergic reaction. There is a strong magnetic field during the MRI scan and you should tell the doctor if you have any Pacemaker or metallic clip or prostheses inside your body. For these scans which require about half an hour, the patient lies down on the couch of thes CT or MRI machines. The couch moves the patient in the large hole or tunnel of these machines. The entire procedure is painless but the sound produced by the MRI machines can be disturbing for some patients. Through the scan the patient shouldn”t move and for kids who may move a lot, sometimes a slight anaesthesia is given.

• Angiogram is an X-ray taken after injecting an iodine dye in catheters positioned into the arteries. This shows the particulars of the blood supply to the tumour. For vascular deformity like AVM it is necessary to plan embolisation, surgery or stereotactic radiation.
• Cerebro Spinal Fluid (CSF) Study is done subsequent to removal the CSF from the spine with a long needle (lumbar puncture). This is done in specific tumours which have a high possibility of diffusion to the spine or to prohibit infections or bleeding.
• Hormonal Blood Tests are done for tumours such as pituitary adenoma, craniopharyngioma, optic chiasmal or hypothalamic glioma.
• Electroencephalogram (EEG) is seldom done to examine the sample of seizures.

What is Encephalitis

Encephalitis is an inflammation of the brain parenchyma (the functional part of the brain). Patients affected have widespread or focal disability of the neurological and psychological function. Encephalitis is different from meningitis, although, clinically, the 2 often occur together with signs and symptoms of meningitis, such as fear of light, headache, or stiff neck.

Encephalitis usually has a viral cause however, it can occur as a result of bacterial or fungal meningitis.

Common viral causes of encephalitis include Herpes Simplex virus (HSV - most common cause), ECHO, Coxsackie, mumps and Epstein-Barr viruses. A well known case in Australia is the Ross River virus.

Who gets Encephalitis?

The occurence rate encephalitis is about 1 in 200,000 per year. The most commonly affected groups are children, the elderly, and those with suppressed immune system.

Approximately 850 cases of encephalitis were reported in 1994. The true statistics of these infections are difficult to obtain because the diagnosis may not be considered, many cases are unreported, or a specific viral cause is never confirmed.

Predisposing Factors

Exposure to viruses can occur through insect bites, food or drink contamination, inhalation of respiratory droplets from an infected person, skin contact, and extremely rarely, vaccinations.

Progression

Most episodes of encephalitis are mild and patients will recover by themselves. In a small number of cases, the disease can be very serious, leading to brain damage, coma and death.

In general however, the fevers and headaches associated with the illness last for 1-2 weeks before gradually improving. Full recovery may take weeks to months.

Probable Outcomes

The prognosis depends on the type of virus and the condition of the patient e.g. general health, age, immune status, and pre-existing brain conditions.

How is Encephalitis Diagnosed?

Tests which may help make the diagnosis of encephalitis include:
# Lumbar puncture: a needle is used to collect fluid from within the spine, and this is analysed.
# EEG: a scan of brain activity, which may be abnormal.
# A CT or MRI scan of the head.
# Special tests can also be done to help identify the cause of the encephalitis.

How is Encephalitis treated?

The goals of treatment are to provide supportive care and relieve symptoms. Antiviral medications may be prescribed for herpes encephalitis or other severe viral infections. Most of the time, however, no specific antiviral drugs are available to combat the infection.

Antibiotics may be prescribed when the infection is caused by bacterial organisms. Anti-epileptic medications are used to suppress seizures if they happen to occur. On rare occasions, potent anti-inflamatory drugs called “steroids” (such as dexamethasone) are used to reduce brain swelling.

Sedatives may be needed to treat irritability or restlessness.

Supportive care (rest, nutrition, fluids) allows the body to fight the infection.

After the acute illness physiotherapy and speech therapy may be needed for rehabiliation.

Encephalitis References

1. Anderson DC, Kozak AJ: Meningitis, encephalitis, and brain abscess. In: Tintinalli JE, et al, eds. Emergency Medicine: A Comprehensive Study Guide. 4th ed . McGraw-Hill; 1997.
2. Centers for Disease Control and Prevention. Summary of notifiable diseases, United States 1994. MMWR 1994;43(53):1-80.
3. Gutierrez KM, Prober CG. Encephalitis: Identifying the specific cause is key to effective management. Postgrad Med 1998; 103(3): 123-5, 129-30, 140-3.
4. Koskiniemi M, Rautonen J, Lehtokoski-Lehtiniemi E, et al. Epidemiology of encephalitis in children: a 20-year survey. Ann Neurol 1991;29(5):492-7
5. Lazoff M. Encephalitis [online]. 2005 [citec 2006 Jan 29]. Available from: URL: http://www.emedicine.com/emerg/topic163.htm
6. UpToDate: Johnson RP, Gluckman SJ. Overview of viral infections of the central nervous system [online]. 2005 [cited 2006 Jan 28]. Available from: URL: http://www.utdol.com/application/topic.asp?file=cns_infe/2236&type=A&selectedTitle=1~68
7. Walls RM: Adult meningitis, encephalitis, and intracranial abscess. In: Rosen P, ed. Emergency Medicine: A Comprehensive Study Guide. 3rd ed. Mosby; 1992.

Drugs/Products Used in the Treatment of This Disease:

* Aciclovir
(Aciclovir)

* Aciclovir (Terry White Chemists)
(Aciclovir)

* Acihexal
(Aciclovir)

* healthsense Aciclovir
(Aciclovir)

* Phenytoin Injection BP (DBL)
(Phenytoin sodium)

* Zovirax Tablets
(Aciclovir)

* Zyclir Tablets
(Aciclovir)

What is Bacterial Meningitis

Meningitis is inflammation of the meninges (membranes) covering the brain and spinal cord. Meningitis may be caused by infection, such as by bacteria or viruses. Non-infectious meningitis is often referred to as “aseptic meningitis”. This article will focus on bacterial meningitis.

Who gets Bacterial Meningitis?

Overall, the annual incidence of bacterial meningitis is approximately 3 cases per 100 000 population. Incidence is affected by such factors as geography, ethnicity, socio-economic status and availability of immunisation against the various infective organisms. Individuals of any age may be affected, but the very young and elderly (>60 years) are more susceptible.

Predisposing Factors

The most common causes of meningitis are viral infections that usually resolve without treatment. Implicated viruses include:

* Enteroviruses (85%-95% of all viral meningitis): including echoviruses and coxsackie viruses
* Herpes viruses
* Epstein-Barr Virus (EBV)
* Cytomegalovirus (CMV)
* HIV and
* Varicella zoster virus.

Bacteria Bacterial infections of the meninges are usually extremely serious illnesses, and potentially may result in death or brain damage even if treated. The most common organisms causing bacterial meningitis, accounting for 80% of all bacterial cases, are:

* Haemophilus influenzae
* Streptococcus pneumoniae (pneumococcus)
* Neisseria meningitidis (meningococcus) Other bacterial organisms causing meningitis include:
* L. monocytogenes: especially in pregnancy, infants under one month of age, adults over 60 years, cancer patients, or the immunosuppressed
* Group B streptococci: infants <1 month
* Escherichia coli: infants <1 month
* Staphylococcus aureus: in patients who have undergone neurosurgery or with a history of head trauma

Risk factors for bacterial meningitis include:

* Extremes of age
* Pregnancy
* Alcoholism
* Diabetes mellitus
* Splenectomy
* Immunodeficiency syndromes
* Head trauma with open skull fracture
* Neurosurgical procedures Meningitis may also be caused by fungi, chemical irritation or drug allergies, and tumours (aseptic meningitis).

Progression

The bacteria which cause acute meningitis may spread to the meninges directly from local structures such as the ear and nasal sinuses, or via the blood stream. Bacterial products then cause an inflammatory response in the body. Inflammatory cells (neutrophils) accumulate in the blood vessels and brain spaces. This is what causes the symptoms and complications of meningitis. Blood vessels in the brain may become blocked, resulting in a stroke or seizure. In some cases, the flow of cerebrospinal fluid may be blocked, causing hydrocephalus (excess CSF in the skull) and raised intracranial pressure, both of which can have serious effects. Distinguishing between acute, subacute, and chronic forms of meningitis may help identify the bacteria or virus causing the problem. Approximately 25% of patients with bacterial meningitis present acutely within 24 hours of onset of symptoms. Other patients with bacterial meningitis and most patients with viral meningitis present with subacute neurologic symptoms developing over 1-7 days. Chronic symptoms lasting longer than 1 week suggest meningitis caused by some viruses as well as tuberculosis, syphilis, fungi (especially cryptococci), and carcinomatous meningitis. Late complications of meningitis include decreased intellectual function, poor memory, seizures and deafness.

Probable Outcomes

Bacterial meningitis is potentially lethal. Depending on the bacteria involved, mortality may be as high as 20%. The early diagnosis and treatment of bacterial meningitis is essential in the prevention of death or permanent nervous system damage. Viral meningitis is usually not serious, and symptoms often disappear within 2 weeks.

How Will Bacterial Meningitis Affect Me?

The classic symptoms of bacterial meningitis are headache, neck stiffness and fever. Other symptoms may include photophobia (sensitivity to light), nausea and vomiting, rash, confusion, irritability and neck stiffness.

How is Bacterial Meningitis Diagnosed?

* Lumbar puncture: this samples the cerebrospinal fluid surrounding the brain. Analysis of the fluid may show immune cells, bacteria, or changes in the composition of the fluid which suggest meningitis.
* Blood cultures
* Blood glucose level
* A CT or MRI of the head looking for hydrocephalus, abscess or cerebral oedema
* Chest and skull x-ray may be appropriate in some cases.

How is Bacterial Meningitis treated?

Bacterial meningitis is an emergency. Prompt intravenous antibiotic treatment of bacterial meningitis is essential. The type of antibiotic prescribed will depend on the type of organisms causing the infection. Antibiotics will be ineffective if the cause is viral. Treatment of secondary symptoms including brain swelling, shock and convulsions will require other medications. Patients may need to be cared for in an intensive care unit (ICU). People who qualify as close contacts of a person with meningitis may require antibiotics to prevent them from getting the disease.

Bacterial Meningitis References

1. Beaman MH, Wesselingh SL. ‘MJA Practice Essentials: Acute community-acquired meningitis and encephalitis.’ MJA 2002, 176(8): 389-396
2. Braunwald, Fauci, Kasper, Hauser, Longo, Jameson. Harrison’s Principles of Internal Medicine. 16th Edition. McGraw-Hill. 2005.
3. Kumar P, Clark M (eds). Clinical Medicine. 6th edition. Elsevier. 2005.
4. Therapeutic Guidelines Limited. Therapeutic Guidelines: Antibiotic. Version 12, 2003.

Drugs/Products Used in the Treatment of This Disease:

* Abelcet
(Amphotericin)

* Amphocil
(Amphotericin)

* Cefotaxime Sodium for Injection (DBL)
(Cefotaxime sodium)

* Cefotaxime-BC
(Cefotaxime sodium)

* Cefoxitin Sodium for Injection (DBL)
(Cefoxitin sodium)

* Ceftriaxone-BC
(Cefotaxime sodium)

* Gentamicin Injection BP
(Gentamicin sulfate)

* Gentamicin Injection BP (DBL)
(Gentamicin sulfate)

* Rimycin
(Rifampicin)