Meningitis
NATIONAL JOURNAL OF HOMOEOPATHY 2003 Nov / Dec VOL V NO 6.
Dr VP Bansal
'Bell / Gels
Anatomy of Meninges:
The brain and spinal cord are covered by three membranes, called meninges .
1. Dura Mater: thick, fibrous and attached to cranium.
2. Arachnoid: lying in-between dura and pia mater.
3. Pia Mater: a delicate membrane which clothes the surface of brain, dipping
into sulci.
Space between arachnoid and pia is sub-arachnoid space, containing cerebrospinal
fluid (CSF)
Key words: Pachy Menigitis: Inflammation of the dura. It is suppuration
between dura and skull. Usually results from cranial osteitis, a subdural
abscess which is a complication of paranasal sinusitis. It was a common
complication of Syphilis.
Leptomeningitis: Inflammation of the pia and arachnoid but commonly referred to
as meningitis.
Types of Meningitis
- Acute
- Subacute
- Chronic
- Pyogenic Meningitis
- Meningo-coccal Meningitis
- Tubercular Meningitis
- Viral Meningitis
- Miscellaneous
I) Direct spread from without:
a. Fracture of the skull with penetrating injury .
b. Fracture of base, organism directly spread from Nasopharynx to meninges.
c. Mastoiditis,
d. Thrombophlebitis of the intracranial venous sinuses.
e. Infection introduced directly through Lumbar puncture.
II) Direct spread from within
a. From brain abscess
b. Tubercular Meningitis from cerebral tuberculoma.
III) Haematogenous (Infection through the blood stream)
Meningitis following bacteraemia. The meningeal infection may be secondary to focal infection elsewhere eg pneumonia, empyema, osteomyelitis, typhoid, gonorrhoea etc. Tubercular meningitis may thus be a manifestation of miliary tuberculosis.
IV) Meningitis complicating encephalitis and myelitis
In such cases meningeal symptoms may not be prominent but CSF yields evidence of Meningeal inflammation. e.g. Viral encephalitis.
IV) Meningism: Signs of meningeal irritation without infection, due to cerebral oedema, commonest in typhoid.
Any disease (including meningitis) is dependent upon three type of causes:
- fundamental causes are most important,
- predisposing causes are next and
- exciting causes are least important.
Clinical Features
Whatever the causative organism in acute meningitis, number of symptoms are common.
Onset: Fulminating, Acute Or Less commonly, insidious.
The triad of Fever, headache and vomiting is pathgnomic of Menigeal irritation. In addition, signs and symptoms of the cause will also be seen.
Headache: increasing in severity is usually the initial symptom with cough and sore throat. Headache is usually very severe and is of ‘bursting’ character. It may be diffuse or mainly frontal and usually radiates down the neck and into the back.
Fever: Fever is a rule. Degree may vary. Temperature range: 37.80 C to 38.90 C. Hyperpyrexia may occur, especially in terminal stages.
Pain: Headache associated with pain in spine which radiates to the limbs, especially lower limbs.
Vomiting: may occur, especially in early stages.
Convulsions: Convulsions common in children, especially in influenzal meningitis.
Lie: The patient tends to lie in an attitude of general flexion, curled up under the sheets and resenting interference.
Cry: High-pitched meningeal cry in infants.
Rash: Several types of rash may occur, the most characteristic being a purpuric eruption which may take form of petechiae. These petechiae are purple at first, fading to a brownish color and do not disappear on pressure. Axillae, flanks, wrists and ankles are most commonly involved sites. Often they are located in the center of lighter-coloured macules and they may become nodular as the disease progresses (sometimes Gonococci may be demonstrated from scrapings of nodular lesion). However absence of rash does not necessarily indicate that the illness will be mild.
Fulminating Meningococcal Meningitis: Also called Waterhouse - Friderichen Syndrome.
It is associated with vasomotor collapse and shock. Unless incipient shock is recognized and managed in time, death from cardiac and/or respiratory failure almost invariably occurs.
Signs of Meningeal Irritation: The following signs are of special value:
- Neck Rigidity: It is present at an early stage in almost every case. It is due to spam of the extensor muscles of the neck and an attempt to overcome this causes pain. Make it routine to check for neck stiffness in every case of a fever with vomiting.
- Head Retraction: is an extreme degree of cervical rigidity. It is a reflex protective spasm.
- Kernig’s Sign: From a position of both knee and hip fully flexed, the knee is extended briskly. If pain and spasm occurs in ham strings, Kernig’s sign is said to be positive.
- Brudzinski’s Sign
- Spontaneous flexion of knee and hip on attempt to flex the neck.
- Spontaneous flexion of one leg, when other is flexed
passively.
Both Kernig’s sign and Brudzinski’s signs are due to presence of inflammatory exudates around roots in the Lumbar theca.
Delirium is common in early stages, but as disease progress, drowsiness and stupor follow, finally coma.
Photophobia: frequently present.
Papilloedema-Fundus may be normal. Shows various congestion Or some times Papilloedema.
Pupils: Often unequal and may react sluggishly. In later stages they tend to be dilated and fixed. Ptosis is common, squint and diplopia are often present. Any of the ocular muscle may be paralysed.
Facial paralysis is not rare.
Dysphagia: May occur in later stages.
Paralysis: Incoordination and tremor are common and there is considerable muscular Hypotonia. A general flaccid paralysis is a terminal event.
Reflexes: are usually sluggish and often soon lost. Abdominal reflexes also disappear early. Planter reflexes are usually flexor at first but later one or both may become extensor.
Sensory: Loss does not usually occur.
Sphincter: control is lost very late. But mental state of the patient may lead to retention or incontinence of urine early in the illness.
Convulsions: Meningitis localized for a time to one hemisphere may cause Jacksonian convulsions hemiparesis and even hemianopia.
Laboratory Findings
TLC 12,000 to 40,000 /cc
DLC Polymorphonuclear Leucocytosis
Hb: Anaemia is common.
Platelets: low count with decreased level of circulating clotting factors as a result of intravascular coagulation.
