Cerebral Meningitis

Cerebral Meningitis

Cerebral Meningitis

 

Cerebral Meningitis


Meningitis is a serious inflammation of meninges, thin membranous covering of the brain and spinal cord. Since meningitis is very serious and dangerous infection because the brain cells are very delicate and if enough brain tissue is damaged by an infection, life-long handicaps will remain. Meninges are the three separate membranes of the brain.these are-

1)Dura layer(outermost layer)

2)Arachnoid  layer(middle layer)

3)Pia layer(inner most layer)

 

Dura layer

It is the toughest, outermost layer of the brain and is closely attached to the inside of the skull.

 

Arachnoid layer

It is the important layer because this layer has involvement of the normal flow of cerebrospinal fluid (CSF) which is the lubricating and nutritive fluid that bathes both brain and spinal cord.

 

Pia layer

It is the inner most layer the pia,  helps the direct blood vessels into the brain.

The space between the arachnoid and pia contains CSF, which protects the brain from trauma. Therefore meningitis is the inflammation (protective attempt by organism to remove injurious stimuli and initiate healing) of the membrane covering the brain and spinal cord collectively called as Meninges. Because of the infection of the brain and spinal cord this condition is classified as Medical Emergency.

 

 

 

Causes of meningitis

Meningitis is usually caused by infection from viruses or microorganisms. Most common are due to infection with viruses, with bacteria, fungi and parasites being the next most common cause. It may also result from non-infectious cause

Bacterial

This  type of bacteria  causes  bacterial meningitis in various age groups. In pre-mature babies/newborns upto 3 months. In old cases group B streptococci causes meningitis. Listeria  Monocytogenes may affect newborn and occur in epidemics. Older children are more commonly affected by Neisseria Meningitidis. Streptococcal pneumoniae also causes meningitis. Recent trauma to the skull lead to bacteria in the nasal cavity and enter the brain causes infection. Meningitis  also occur in individuals whose immune system is impaired i.e. fight against infection get reduced or entirely absent. People having infection in head, neck and ear can lead to meningitis.

Tuberculous meningitis, meningitis due to infection with mycobacterium tuberculosis, where tuberculosis is common and common in AIDS patients.

Aseptic

This is usually due to virus but it may be due to bacterial meningitis. Fungal meningitis for example due to Cryptococcus neoformans, typically seen inpeople with immune deficiency . amoebic meningitis, due to infection with amoeba such as naeglesia fowleri common in fresh water sources.

Viral

Virus that causes meningitis include enterovirus, herpes simplex virus type-2, varicella zoaster virus, mumps virus

Parasitic

This cause is assumed when there is increased level of eosinophills (a type of blood cells) in CSF . common parasites are– Angiostrongylus cantonesis, gnathostoma spinigerum.

Non infectious cause

It occur as a result of non-infectious causes like spread of cancer to meninges(malignant meningitis) and certain drugs (antibiotics ) rarely migraine causes meningitis.

Mechanism

When bacteria reaches the meningis by one of two main routes i.e. through blood stream or through direct contact between meningis and nasal cavity. Once bacteria enter the blood stream, they entered the subarachnoid space. As a result there is large scale inflammation occur in the space, because of the response of immune system to the entry of bacteria into the CNS large amount of cytokines released and lead to cerebral edema(swelling of brain due to fluid leakage from blood vessels. When large number of white blood cells enters CSF, causing inflammation of meninges, leading to edema (interstitial edema)i.e. swelling due to fluid between cells. In addition to this blood vessels become  inflamed leads to decreased blood flow causing cytotoxic edema.. these form of edema lead to increased intracranial pressure causes infection.

 

 

Clinical features

In adults, severe headache is the most common symptom of meningitis occur in 90% of cases, followed by nuchal rigidity (inability to bend the neck forward due to increased neck muscle tone)nuchal rigidity, high fever and altered mental status are the three important features that mainly present in44-46% of cases. Other signs include-

Photophobia(intolerant to bright light), phonophobia(intolerant to loud noise), vomiting dizziness, seizures,. Joint pains.

Small children may become irritable and look unwell. In infant upto 6 months of age bulging(soft spot on top of baby’s head)may present. High pitch moaning cry, dislike of being handled, blank expression, refuse to feed.

In meningitis certain sign’s are present

a) Brudzinski’s sign is present in which when we flex(bend the neck forward)it causes involuntary flexion of knee and hip.

b) kernig’s sign is also present. In this  patient lies in supine (lying down with face up)with hip and knee bend. This test is positive when some body bends  the  knee it causes pain. )

c) jolt accentuation manoeuvre which helps to determine meningitis reporting fever and headache.The patient is told to rapidly rotate his or her head horizontally if it does not makes the headache worse, meningitis is unlikely.

In menengiococcal meningitis(meningitis caused by neisseria meningitdis) rashes are common(small, numerous, irregular, purple/red spots mainly on trunk, lower extremities, palm of hands, sole of foot, mucus membrane and conjuctiva.

 

 

 

Diagnosis of meningitis

The most important test in identifying or ruling out meningitis is analysis of CSF through lumbar puncture. It is contraindicated(not done) if there is mass in the brain or intracranial pressure is elevated.

Lumbar puncture is done by positioning the patient, usually lying on the side, applying local anaesthetic and inserting a needle into the dural sac(sac around spinal cord)to collect CSF. When this has been achieved the “opening pressure “of the CSF is measured by using a manometer. The pressure is normally between 6 and 18 cm water. In bacterial meningitis pressure is elevated. If fluid is cloudy, high level of protein, white and RBC’s or bacteria suggest bacterial meningitis.

 

 

Article publié pour la première fois le 02/07/2011

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Cerebral palsy stages and Risk factors..

stage of cp

   INTRODUCTION    

Cerebral palsy is a group of disorders that mainly affects  body movements, balance and posture. In simple words Cerebral palsy  is also known as BRAIN PARALYSIS. It mainly affects the early childhood i.e. during infancy . In this disease , there is delay in the developmental milestones such as rolling , crawling, sitting and walking.

Cerebral palsy is mainly caused  because of damage in one or more parts of the brain that mainly controls the movements of the muscles  and its tone which  leads to the in coordination of the movements. Patient finds difficulty in  normal activities like balance, walking, speaking and swallowing.

stage of cp

 

STAGES OF CEREBRAL PALSY

Cerebral palsy has many types.The main  types of Cerebral palsy..

1) Spastic  Cerebral palsy

2) Dys kinetic  cerebral palsy

3) mixed cerebral palsy.

  Spastic cerebral palsy–

In spastic cerebral palsy there is increased in the muscle tone. Classification of this type mainly  depends on the body part affected. For example if both the legs are affected it is known as DIPLEGIA. In some cases there is involvement of one side of body then it is called as HEMIPLEGIA. When whole body involvement is there it is known as QUADRIPLEGIA.

   Dyskinetic cerebral palsy–

It mainly affects  coordination of movements. It is further divided into

a) Athetoid  cerebral palsy—– In this the person has uncontrolled movements and these movements can affect any part of the body including  face , mouth, or tongue.

b) Ataxic Cerebral palsy— It mainly affects  balance and coordination of the patient. In this deep perception is mainly affected. Gait of the person is improper. Patient generally finds difficulty in standing.

 Mixed Cerebral palsy–

The other type is mixed type which mainly involves combination of spastic and athetoid  cerebral palsy.

RISK FACTORS OF CEREBRAL PALSY–

Cerebral palsy mainly involves the brain and nervous system  functions. Most of these problem occurs during first  2 years of life or sometimes while the baby’s brain is still developing. There is involvement of many risk factors that can cause cerebral palsy

1) Premature infants have the highest risk  of developing cerebral palsy  because of under development of many organs of the body.

2) Infection of brain like Encephalitis ( inflammation , irritation or swelling of the brain) , meningitis ( bacterial infection of the membranes covering meninges and spinal cord) or herpes simplex infection.

3) Infection  to the mother during pregnancy due to rubella virus.

4) Head injury or bleeding in the brain.

5) RH factor in compatibility– Difference in the mother and fetus blood causes brain damage in fetus . Most of the times it is detects early and treated in women.

6) Hypoxia  lack of oxygen  reaching the brain before or after the birth.

7) Severe jaundice.

8) Complications during labor or delivery.

 

 

Article publié pour la première fois le 06/03/2013

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