Streptococcal meningitis

Neurology

Clinicals - History

Fact Explanation
Introduction Meninges are the lining that covers the brain and spinal cord. Meningitis is inflammation of the meninges around the brain and spinal cord. It is usually caused by an infectious pathogens such as bacteria, virus, fungi and parasites. Depending on he duration of the symptoms, it can be subdivided into acute and chronic form. Bacterial meningitis is a medical emergency requiring immediate treatment. Streptococcus pneumoniae is the most commonest causative pathogens for bacterial meningitis. There are other streptococcal sp. that can occasionaly cause meningitis such as streptococcus bovis (nonenterococcal, group D streptococcus), streptococcus suis etc. Group A streptococci are an uncommon cause of meningitis. Majority of patients with meningitis due to non-beta-hemolytic streptococci are found to have various underlying diseases. Invasion of the bloodstream can occur directly through skin abrasions or the oral or respiratory route that can results in sepsis and other complications. Introduction
Meninges are the lining that covers the brain and spinal cord. Meningitis is inflammation of the meninges around the brain and spinal cord. It is usually caused by an infectious pathogens such as bacteria, virus, fungi and parasites. Depending on he duration of the symptoms, it can be subdivided into acute and chronic form. Bacterial meningitis is a medical emergency requiring immediate treatment. Streptococcus pneumoniae is the most commonest causative pathogens for bacterial meningitis. There are other streptococcal sp. that can occasionaly cause meningitis such as streptococcus bovis (nonenterococcal, group D streptococcus), streptococcus suis etc. Group A streptococci are an uncommon cause of meningitis. Majority of patients with meningitis due to non-beta-hemolytic streptococci are found to have various underlying diseases. Invasion of the bloodstream can occur directly through skin abrasions or the oral or respiratory route that can results in sepsis and other complications.
Headache Once the organism entered through the blood brain barrier, immune system of the body gets activated to release various cytokines and chemikines. Further it releases reactive oxygen radicals to cause more endothelial and nearby tissue damage. These can cause meningeal irritation, increased intracranial damage and cerebral edema. Headache
Once the organism entered through the blood brain barrier, immune system of the body gets activated to release various cytokines and chemikines. Further it releases reactive oxygen radicals to cause more endothelial and nearby tissue damage. These can cause meningeal irritation, increased intracranial damage and cerebral edema.
Fever Inflammation of the meninges and endothelium releases pyrogens causing fever. Fever
Inflammation of the meninges and endothelium releases pyrogens causing fever.
Vomiting Vomiting is a common finding in the meningitis. Vomiting
Vomiting is a common finding in the meningitis.
Sensitivity to light (photophobia) Inability to tolerate light is due to the meningism that indicates inflammatory activation of the trigeminal sensory nerve fibers in the meninges. Sensitivity to light (photophobia)
Inability to tolerate light is due to the meningism that indicates inflammatory activation of the trigeminal sensory nerve fibers in the meninges.
Pain during retraction of the neck Due to the meningeal irritation. Pain during retraction of the neck
Due to the meningeal irritation.
Seizures Altered cerebral perfusion pressure can cause reduction of the cerebral blood flow and ischaemia. Seizures
Altered cerebral perfusion pressure can cause reduction of the cerebral blood flow and ischaemia.
Decreased alertness and drowsiness There can be increased intracranial pressure which may be due to the increased blood brain barrier permeability, swelling of the cellular elements of the brain, interstitial edema results from obstruction of flow in normal CSF pathways etc. Neuronal cell death and cerebral edema may also contribute to the drowsiness. Decreased alertness and drowsiness
There can be increased intracranial pressure which may be due to the increased blood brain barrier permeability, swelling of the cellular elements of the brain, interstitial edema results from obstruction of flow in normal CSF pathways etc. Neuronal cell death and cerebral edema may also contribute to the drowsiness.
Excessive crying, refusing the feeds Infants and young children present with nonspecific features. Excessive crying, refusing the feeds
Infants and young children present with nonspecific features.
Hearing loss Inflammation can extends to the cranial nerves, when the 8th nerve is involved that causes sensorineural type hearing loss. Hearing loss
Inflammation can extends to the cranial nerves, when the 8th nerve is involved that causes sensorineural type hearing loss.
Visual problems Visual problems Involvement of the optic and other cranial nerves related to the vision can be the cause. Visual problems
Visual problems Involvement of the optic and other cranial nerves related to the vision can be the cause.
History of immunodeficiency People with immune deficiency like malignancy, chemotherapy, long term steroid use, organ transplant and HIV AIDS are particularly vulnerable for the disease. History of immunodeficiency
People with immune deficiency like malignancy, chemotherapy, long term steroid use, organ transplant and HIV AIDS are particularly vulnerable for the disease.
Skin infections Group A streptococci are an important causative factors for the soft tissue infections. Skin infections
Group A streptococci are an important causative factors for the soft tissue infections.
Sorethroat and ear discharge Group a beta-hemolytic streptococci are a common cause of pharyngitis and ear infections. Sorethroat and ear discharge
Group a beta-hemolytic streptococci are a common cause of pharyngitis and ear infections.
Other organ involvement Streptococci may affect the other organs in the body causing arthritis, pneumonia, endocarditis, endophthalmitis, and spontaneous bacterial peritonitis. Other organ involvement
Streptococci may affect the other organs in the body causing arthritis, pneumonia, endocarditis, endophthalmitis, and spontaneous bacterial peritonitis.
History of handling or eat undercooked pork, e.g., farm workers, butchers, and slaughterhouse workers Streptococcus suis meningitis who handle or eat undercooked pork, e.g., farm workers, butchers, and slaughterhouse workers. History of handling or eat undercooked pork, e.g., farm workers, butchers, and slaughterhouse workers
Streptococcus suis meningitis who handle or eat undercooked pork, e.g., farm workers, butchers, and slaughterhouse workers.
History of maternal pyrexia Mothers of neonates who develop group A streptococcal meningitis are mostly found to have peurperal sepsis and toxic shock syndrome. These mothers transmit the infection to the baby during the delivery : vertical transmission. History of maternal pyrexia
Mothers of neonates who develop group A streptococcal meningitis are mostly found to have peurperal sepsis and toxic shock syndrome. These mothers transmit the infection to the baby during the delivery : vertical transmission.

Clinicals - Examination

Fact Explanation
Febrile Fever is one of the most common presenting features. This is due to the infection. Febrile
Fever is one of the most common presenting features. This is due to the infection.
Stiff neck Nuchal rigidity is present due to the meningeal irritation. Stiff neck
Nuchal rigidity is present due to the meningeal irritation.
Kernig sign This is a bedside diagnostic sign used to evaluate suspected cases of meningitis. Patient is kept in supine position, hip and knee are flexed, the knee is slowly extended by the examiner. It is positive if there is a resistance or pain during extension. Kernig sign
This is a bedside diagnostic sign used to evaluate suspected cases of meningitis. Patient is kept in supine position, hip and knee are flexed, the knee is slowly extended by the examiner. It is positive if there is a resistance or pain during extension.
Brudzinki sign Another sign of meningeal irritation. First one hand is kept behind the patient's head and the other on chest in order to prevent the patient from rising, passive flexion of the neck produces reflex flexion of the patient's hips and knees in a positive Brudzinski's sign. Brudzinki sign
Another sign of meningeal irritation. First one hand is kept behind the patient's head and the other on chest in order to prevent the patient from rising, passive flexion of the neck produces reflex flexion of the patient's hips and knees in a positive Brudzinski's sign.
Tachycardia and hypotension Fast heart rate is observed in hypotensive, confused patients. Tachycardia and hypotension
Fast heart rate is observed in hypotensive, confused patients.
Mental status changes Alteration in mental status is a poor prognostic indicator. Mental status changes
Alteration in mental status is a poor prognostic indicator.
Focal neurological signs Subdural effusion or cerebral-space-occupying lesions such as abscess formation can cause these symptoms. Focal neurological signs
Subdural effusion or cerebral-space-occupying lesions such as abscess formation can cause these symptoms.
Buldging of fontanelle Due to the increased intracranial pressure. Buldging of fontanelle
Due to the increased intracranial pressure.
Growth retardation and cognitive impairment Ischaemia can cause neuronal cell death and tissue damage, if the developing brain is affected child may ends up with poor growth. Cognitive impairment is most prominent after pneumococcal meningitis. Growth retardation and cognitive impairment
Ischaemia can cause neuronal cell death and tissue damage, if the developing brain is affected child may ends up with poor growth. Cognitive impairment is most prominent after pneumococcal meningitis.
Sensorineural hearing loss Cranial nerve palsies specially VIII the nerve palsy is the cause for this hearing loss. Sensorineural hearing loss
Cranial nerve palsies specially VIII the nerve palsy is the cause for this hearing loss.
Papilloedema This is due to the increased intracranial pressure. Increased blood brain barrier permeability, swelling of the cellular elements of the brain, interstitial edema results from obstruction of flow in normal CSF pathways as in hydrocephalus are the possible causes for the raised intracranial pressure. Papilloedema
This is due to the increased intracranial pressure. Increased blood brain barrier permeability, swelling of the cellular elements of the brain, interstitial edema results from obstruction of flow in normal CSF pathways as in hydrocephalus are the possible causes for the raised intracranial pressure.
Hydrocephalus There can be involvement of the ventricles causing ventriculitis. Inflamed areas are gradually fibrosed with creating an obstruction to the cerebrospinal fluid outflow, leading to hydrocephalus. Hydrocephalus
There can be involvement of the ventricles causing ventriculitis. Inflamed areas are gradually fibrosed with creating an obstruction to the cerebrospinal fluid outflow, leading to hydrocephalus.
Ear discharge/ inflammed pharynx Group a beta-hemolytic streptococci are a common cause of pharyngitis/ upper respiratory tract infections. Ear discharge/ inflammed pharynx
Group a beta-hemolytic streptococci are a common cause of pharyngitis/ upper respiratory tract infections.
Skin sepsis Group a beta-hemolytic streptococci are also responsible for the soft tissue infection. Skin sepsis
Group a beta-hemolytic streptococci are also responsible for the soft tissue infection.

Investigations - Diagnosis

Fact Explanation
Lumbar puncture Opening pressure will be elevated in meningitis. Regarding the protein content in the CSF, in bacterial meningitis there is markedly elevated protein (< 1 g/l), where as in other types that may be less prominent. CSF glucose level is decreased. Markedly elevated white blood cell count with predominant neutrophils is seen in streptococcal meningitis. Bacterial antigen detection in the CSF for Streptococcus pneumoniae will be positive. Lumbar puncture
Opening pressure will be elevated in meningitis. Regarding the protein content in the CSF, in bacterial meningitis there is markedly elevated protein (< 1 g/l), where as in other types that may be less prominent. CSF glucose level is decreased. Markedly elevated white blood cell count with predominant neutrophils is seen in streptococcal meningitis. Bacterial antigen detection in the CSF for Streptococcus pneumoniae will be positive.
Blood culture Is done if the patient seems to be septic or lumbar puncture can not be done safely due to the possibility of increased intracranial pressure before the antibiotics. Blood culture will isolate gram-positive cocci in pairs and chains. Blood culture
Is done if the patient seems to be septic or lumbar puncture can not be done safely due to the possibility of increased intracranial pressure before the antibiotics. Blood culture will isolate gram-positive cocci in pairs and chains.
Full blood count There can be elevated lymphocytes/leucocytes in the blood. Full blood count
There can be elevated lymphocytes/leucocytes in the blood.
Gram stain of the ear discharge Ear discharge analysis will show a small amount of pus cells and large numbers of Gram-positive cocci. Gram stain of the ear discharge
Ear discharge analysis will show a small amount of pus cells and large numbers of Gram-positive cocci.
Computer tomography(CT) scan of the head and Magnetic Resonance Imaging(MRI) CT scan will be even better as the first investigation specially to rule out the possibility of increased intracranial pressure before doing lumbar puncture. MRI will demonstrate the inflammatory dural meningeal process with enhanced uptake over the affected areas. This also show the intracranial complications such as brain edema, hydrocephalus and infarcts. Computer tomography(CT) scan of the head and Magnetic Resonance Imaging(MRI)
CT scan will be even better as the first investigation specially to rule out the possibility of increased intracranial pressure before doing lumbar puncture. MRI will demonstrate the inflammatory dural meningeal process with enhanced uptake over the affected areas. This also show the intracranial complications such as brain edema, hydrocephalus and infarcts.

Investigations - Management

Fact Explanation
Lumbar puncture Lumbar puncture Is done during the follow up and when the response is poor to the current treatment within 48 hours of treatment. Lumbar puncture
Lumbar puncture Is done during the follow up and when the response is poor to the current treatment within 48 hours of treatment.
CT imaging CT imaging is performed if there is poor response within 48 hours of antibiotic treatment. This may be due to the potential complications of the disease. CT imaging
CT imaging is performed if there is poor response within 48 hours of antibiotic treatment. This may be due to the potential complications of the disease.
Erythrocyte sedimentation rate(ESR) and C Reactive protein(CRP) Is elevated due to the inflammation. Erythrocyte sedimentation rate(ESR) and C Reactive protein(CRP)
Is elevated due to the inflammation.
Renal functions and serum electrolytes Syndrome of inappropriate Antidiuretic Hormone secretion is a complication of meningitis. This can cause hyponatraemia. Reduced intake of fluids can cause electrolyte imbalances. Medications may alter the renal functions and therefore baseline value is also needed. Renal functions and serum electrolytes
Syndrome of inappropriate Antidiuretic Hormone secretion is a complication of meningitis. This can cause hyponatraemia. Reduced intake of fluids can cause electrolyte imbalances. Medications may alter the renal functions and therefore baseline value is also needed.
Liver function tests Medications may alter the liver functions and therefore baseline value is needed before the treatment. Liver function tests
Medications may alter the liver functions and therefore baseline value is needed before the treatment.
Random blood sugar Should be done immediately especially if the patient is drowsy, to rule out the hypoglycaemia. Random blood sugar
Should be done immediately especially if the patient is drowsy, to rule out the hypoglycaemia.
MRI/CT brain Increased intracranial pressure is evident on MRI by severe sulcal effacement and midline shift on brain imaging. Therefore cranial CT should be done before the lumbar puncture, specially in those present with focal neurological deficits or seizures and those who have a disturbed consciousness due to the possible risk of cerebral herniation due to raised intracranial pressure. MRI/CT brain
Increased intracranial pressure is evident on MRI by severe sulcal effacement and midline shift on brain imaging. Therefore cranial CT should be done before the lumbar puncture, specially in those present with focal neurological deficits or seizures and those who have a disturbed consciousness due to the possible risk of cerebral herniation due to raised intracranial pressure.

Management - Supportive

Fact Explanation
Immediate management This is particularly important if the patient presents with confusion and drowsiness. Airway, breathing, circulation, disability and environment need to be attended. Random blood sugar is done to exclude hypoglycaemia. Lumbar puncture needs to be done before the antibiotics started ( if the possibility of increased intracranial pressure can be rule out) If it is not safe to do the LP blood culture is done and antibiotics are started as soon as possible without delay. Immediate management
This is particularly important if the patient presents with confusion and drowsiness. Airway, breathing, circulation, disability and environment need to be attended. Random blood sugar is done to exclude hypoglycaemia. Lumbar puncture needs to be done before the antibiotics started ( if the possibility of increased intracranial pressure can be rule out) If it is not safe to do the LP blood culture is done and antibiotics are started as soon as possible without delay.
Supportive management Antipyretics (i.e. acetaminophen) and antiemetics, (i.e.promethazine) may be given. Hydration should be checked and due to the possibility of syndrome of inappropriate Antidiuretic hormone, 2/3 of maintenance is preferable. Usual recommended fluid intake is less than 800 mg/day. Monitoring of the vital parameters should be done during the initial period. Supportive management
Antipyretics (i.e. acetaminophen) and antiemetics, (i.e.promethazine) may be given. Hydration should be checked and due to the possibility of syndrome of inappropriate Antidiuretic hormone, 2/3 of maintenance is preferable. Usual recommended fluid intake is less than 800 mg/day. Monitoring of the vital parameters should be done during the initial period.
Management of the complications Ventriculoperitoneal (VP) shunt is placed for the symptomatic improvement in hydrocephalus. If there are seizures, anticonvulsants should be continued and close follow-up should be done. If there is of rapidly increasing intracranial pressure with clinical deterioration where medical treatment failed, surgical decompression has to be considered as a life saving measure. Extracranial complications such as sepsis, disseminated coagulopathy, multiorgan failure, arthritis and electrolyte imbalance, can occur due to the usually syndrome of inappropriate antidiuretic hormone (SIADH) secretion. Management of the complications
Ventriculoperitoneal (VP) shunt is placed for the symptomatic improvement in hydrocephalus. If there are seizures, anticonvulsants should be continued and close follow-up should be done. If there is of rapidly increasing intracranial pressure with clinical deterioration where medical treatment failed, surgical decompression has to be considered as a life saving measure. Extracranial complications such as sepsis, disseminated coagulopathy, multiorgan failure, arthritis and electrolyte imbalance, can occur due to the usually syndrome of inappropriate antidiuretic hormone (SIADH) secretion.
Management of associated streptococcal infections Group A streptococci may be involved in the causation of the pharyngitis and skin infections. Appropriate antibiotics with penicilllin and wound care are needed. Management of associated streptococcal infections
Group A streptococci may be involved in the causation of the pharyngitis and skin infections. Appropriate antibiotics with penicilllin and wound care are needed.
Follow up As they are vulnerable for complications such as hearing loss, vision problems, growth retardation, learning disability they need to be followed up with hearing, vision and growth assessment. Follow up
As they are vulnerable for complications such as hearing loss, vision problems, growth retardation, learning disability they need to be followed up with hearing, vision and growth assessment.

Management - Specific

Fact Explanation
Antibiotic therapy Aims of the therapy would be to treat the infection and prevention of long-term central nervous system sequelae. Diagnostic delays should not be a cause fro delaying the immediate antibiotic therapy. Emperical treatment is started usually with the ceftriaxone, vancomycin, and ampicillin and then changed according to the culture results with antibiotic sensitivity report. Targeted antimicrobial therapy would be penicillin G, 24 million units intravenously per day. But currently it has been suggested third generation cephalosphorins as the first line drug in pneumococcal meningitis due to the resistance of organism to the penicillin and inadequate penetration into the central nervous system to target these resistant organisms. Other antibiotics that can be use to treat the streptococcal meningitis are amino glycosides, second and third generation cephalosporin, and vancomycin. Antibiotic therapy
Aims of the therapy would be to treat the infection and prevention of long-term central nervous system sequelae. Diagnostic delays should not be a cause fro delaying the immediate antibiotic therapy. Emperical treatment is started usually with the ceftriaxone, vancomycin, and ampicillin and then changed according to the culture results with antibiotic sensitivity report. Targeted antimicrobial therapy would be penicillin G, 24 million units intravenously per day. But currently it has been suggested third generation cephalosphorins as the first line drug in pneumococcal meningitis due to the resistance of organism to the penicillin and inadequate penetration into the central nervous system to target these resistant organisms. Other antibiotics that can be use to treat the streptococcal meningitis are amino glycosides, second and third generation cephalosporin, and vancomycin.
Steroids Dexamethasone (4 mg every six hours) is given to reduce the inflammatory response occur during the anti microbial treatment. Dexamethasone may reduce the incidence of hearing loss in some patients. Steroids
Dexamethasone (4 mg every six hours) is given to reduce the inflammatory response occur during the anti microbial treatment. Dexamethasone may reduce the incidence of hearing loss in some patients.
Pneumococcal conjugate vaccine Pneumococcal conjugate vaccine is important in preventing the invasive pneumococcal diseases. It is a10 valen congugated pneumococcal and some countries have included it in the routine immunization progrrame. Pneumococcal conjugate vaccine
Pneumococcal conjugate vaccine is important in preventing the invasive pneumococcal diseases. It is a10 valen congugated pneumococcal and some countries have included it in the routine immunization progrrame.

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