Benign recurrent meningitis - Clinicals, Diagnosis, and Management

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. Benign recurrent meningitis is a rare recurrent nature with symptom-free intervals between episodes and is characterized by short episodes of meningitis with CSF lymphocytosis. Attacks occur suddenly, maximal within few hours and may last for three days or longer. Duration of the disease may span from 1-11 years or longer. Interval between an episode may vary, but may be longer at the onset of the disease and latter part of the disease. 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. Benign recurrent meningitis is a rare recurrent nature with symptom-free intervals between episodes and is characterized by short episodes of meningitis with CSF lymphocytosis. Attacks occur suddenly, maximal within few hours and may last for three days or longer. Duration of the disease may span from 1-11 years or longer. Interval between an episode may vary, but may be longer at the onset of the disease and latter part of the disease.
Headache Benign recurrent meningitis is associated with chronic, recurrent episodes of headache. Headache is non specific symptom occurring due to meningeal irritation. Headache
Benign recurrent meningitis is associated with chronic, recurrent episodes of headache. Headache is non specific symptom occurring due to meningeal irritation.
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), Pain during retraction of the neck Inability to tolerate light is known as photophobia. These are symptoms of meningeal irritation. Sensitivity to light (photophobia), Pain during retraction of the neck
Inability to tolerate light is known as photophobia. These are symptoms of meningeal irritation.
Phonophobia, vertigo, syncope Phonophobia is as a persistent, abnormal, and unwarranted fear of sound. Vertigo and syncopy are also associated features of meningitis. Phonophobia, vertigo, syncope
Phonophobia is as a persistent, abnormal, and unwarranted fear of sound. Vertigo and syncopy are also associated features of meningitis.
Seizures Altered cerebral perfusion pressure can cause reduction of the cerebral blood flow and ischaemia. These are transient neurological deficits and may be in the form of grandmal seizures. Seizures
Altered cerebral perfusion pressure can cause reduction of the cerebral blood flow and ischaemia. These are transient neurological deficits and may be in the form of grandmal seizures.
Decreased alertness and drowsiness This may be due to raised intracranial pressure & cerebral edema causing parahippocampal gyri herniation. Neuronal cell death may also contribute to the drowsiness. Decreased alertness and drowsiness
This may be due to raised intracranial pressure & cerebral edema causing parahippocampal gyri herniation. Neuronal cell death 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. Blurred vision is due to raised ICP causing shift of midline structures, and inflammation of nerve roots giving rise to 3rd & 6th cranial nerve palsy etc. Visual problems
Visual problems Involvement of the optic and other cranial nerves related to the vision can be the cause. Blurred vision is due to raised ICP causing shift of midline structures, and inflammation of nerve roots giving rise to 3rd & 6th cranial nerve palsy etc.
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.

Clinicals - Examination

Fact Explanation
Febrile Fever is one of the most common presenting features. Temperature may high as 40 centigrades during an episode. Febrile
Fever is one of the most common presenting features. Temperature may high as 40 centigrades during an episode.
Stiff neck Due to the meningeal irritation. Stiff neck
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.
Focal neurological signs Focal neurogical signs occur due to raised ICP or due to inflammatory exudates along nerve roots and cerebral ischemia due to vascular inflammation and thrombosis. These are transient and may resolve within seven days. Focal neurological signs
Focal neurogical signs occur due to raised ICP or due to inflammatory exudates along nerve roots and cerebral ischemia due to vascular inflammation and thrombosis. These are transient and may resolve within seven days.
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.
Papilloedema This is the optic disc swelling due to the increased intracranial pressure. Papilloedema
This is the optic disc swelling due to the increased intracranial pressure.
Sensorineural hearing loss Permanent neurological impairments are rare in benign recurrent meningitis. Sensorineural hearing loss
Permanent neurological impairments are rare in benign recurrent meningitis.
Signs of immunodeficiency : febrile, Respiratory system-crepitations, features of fungal infections, skin ulcers People with immune deficiency like malignancy, chemotherapy, long term steroid use, organ transplant and HIV AIDS are particularly vulnerable for the disease. Signs of immunodeficiency : febrile, Respiratory system-crepitations, features of fungal infections, skin ulcers
People with immune deficiency like malignancy, chemotherapy, long term steroid use, organ transplant and HIV AIDS are particularly vulnerable for the disease.

Investigations - Diagnosis

Fact Explanation
Lumbar puncture Opening pressure will be normal/elevated in meningitis. Regarding the protein content in the CSF, it is mildly elevated. There will be polymorphonuclear pleocytocis in the first 24hours and lymphocytic thereafter which also dissapears rapidly within days. CSF glucose content is rarely reduced. Gram stain & culture ABST can identify the causative organism. There is a large type of cell called endothelial/Mollaret's cell. Immuocytologic studies are able to identify these cells by its irregular, vague outlined nuclear and cytoplasmic membranes and tendancy to undergo rapid lysis. These cells may appear as "ghosts" and will be not seen after the first few hours of onset of attack. Lumbar puncture
Opening pressure will be normal/elevated in meningitis. Regarding the protein content in the CSF, it is mildly elevated. There will be polymorphonuclear pleocytocis in the first 24hours and lymphocytic thereafter which also dissapears rapidly within days. CSF glucose content is rarely reduced. Gram stain & culture ABST can identify the causative organism. There is a large type of cell called endothelial/Mollaret's cell. Immuocytologic studies are able to identify these cells by its irregular, vague outlined nuclear and cytoplasmic membranes and tendancy to undergo rapid lysis. These cells may appear as "ghosts" and will be not seen after the first few hours of onset of attack.
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.
PCR Important in identification of herpes simplex virus (HSV). PCR is also important for diagnosing tuberculosis. PCR
Important in identification of herpes simplex virus (HSV). PCR is also important for diagnosing tuberculosis.
Full blood count There can be elevated leucocytosis, leucopenia and eosinophilia in the blood. It is also important to exclude the other causes for the fever such as low platelets in viral infections, high white blood cells (leucocytosis) in bacterial infections. Full blood count
There can be elevated leucocytosis, leucopenia and eosinophilia in the blood. It is also important to exclude the other causes for the fever such as low platelets in viral infections, high white blood cells (leucocytosis) in bacterial infections.
IgM/IgG level IgM/iGg level is elevated in the CSF of some patients. IgM/IgG level
IgM/iGg level is elevated in the CSF of some patients.
ESR ESR is elevated in association with inflammation of the meninges. ESR is also elevated in vasculitides, tuberculosis which are differential diagnoses of benign recurrent meningitis. ESR
ESR is elevated in association with inflammation of the meninges. ESR is also elevated in vasculitides, tuberculosis which are differential diagnoses of benign recurrent meningitis.
Blood culture and antibiogram Is important to exclude the other causes of meningitis such as bacterial meningitis and to assess the antibiotic sensitivity of the organism. Blood culture and antibiogram
Is important to exclude the other causes of meningitis such as bacterial meningitis and to assess the antibiotic sensitivity of the organism.
Blood picture Monocytes usually occur singly or in small aggregates and show atypical cell morphology such as deeply lobated or cleft nuclei. Normocytic and normochromic anaemia is seen in vascultic conditions. Blood picture
Monocytes usually occur singly or in small aggregates and show atypical cell morphology such as deeply lobated or cleft nuclei. Normocytic and normochromic anaemia is seen in vascultic conditions.
Chest X ray Tuberculous meningitis is the most serious manifestation of tuberculosis. It gives a picture similar to that of benign recurrent meningitis. Chest x ray is important for diagnosing tuberculosis. Chest X ray
Tuberculous meningitis is the most serious manifestation of tuberculosis. It gives a picture similar to that of benign recurrent meningitis. Chest x ray is important for diagnosing tuberculosis.

Investigations - Management

Fact Explanation
Renal function tests Follow up is needed as Syndrome of inappropriate Antidiuretic Hormone secretion , hyponatraemia and other electrolyte imbalances can occur as complications of meningitis. Renal function tests
Follow up is needed as Syndrome of inappropriate Antidiuretic Hormone secretion , hyponatraemia and other electrolyte imbalances can occur as complications of meningitis.
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.
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.
Random blood sugar Should be done immediately especially if the patient is drowsy, to rule out the hypoglycaemia as cause for drowsiness. It is also needed to compare with CSF sugar. The normal value of CSF sugar is closer to the 1/3 of the serum value. CSF sugar values are reduced in bacterial and tuberculous meningitis. Random blood sugar
Should be done immediately especially if the patient is drowsy, to rule out the hypoglycaemia as cause for drowsiness. It is also needed to compare with CSF sugar. The normal value of CSF sugar is closer to the 1/3 of the serum value. CSF sugar values are reduced in bacterial and tuberculous meningitis.
Screening for viral infections Viral infections like Epstein Bar virus, coxackie virus B2 and B5, echoviruses 7 and 9, Hepes simplex virus type 1 and 2 are known to be associated with benign recurrent meningitis. PCR is done to detect HSV meningitis. Screening for viral infections
Viral infections like Epstein Bar virus, coxackie virus B2 and B5, echoviruses 7 and 9, Hepes simplex virus type 1 and 2 are known to be associated with benign recurrent meningitis. PCR is done to detect HSV meningitis.
Screening for vasculitides EG:- ANCA (antineutrophil cytoplasmic antibody), Cryoglobulin, Complement levels, Eosinophil counts/IgE levels Vasculitides is a differential diagnosis of benign recurrent meningitis. These are used to identify the specific cause of vasculitides. Screening for vasculitides EG:- ANCA (antineutrophil cytoplasmic antibody), Cryoglobulin, Complement levels, Eosinophil counts/IgE levels
Vasculitides is a differential diagnosis of benign recurrent meningitis. These are used to identify the specific cause of vasculitides.

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 ( only if the possibility of increased intracranial pressure can be rule out preferably by a CT scan of the head) 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 ( only if the possibility of increased intracranial pressure can be rule out preferably by a CT scan of the head) 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. Monitoring of the vital parameters including the neurological status should be done during the initial period. Suppressing coughing and straining will be helpful. Pain relief may be needed for severe headache, arthralgia, myalgia. 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. Monitoring of the vital parameters including the neurological status should be done during the initial period. Suppressing coughing and straining will be helpful. Pain relief may be needed for severe headache, arthralgia, myalgia.
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. 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.
Patient isolation Is needed for the meningococcal disease during the first 24 h of treatment. Patient isolation
Is needed for the meningococcal disease during the first 24 h of treatment.
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. But these complications are less frequent than in other types of meningitis. 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. But these complications are less frequent than in other types of meningitis.

Management - Specific

Fact Explanation
Pharmacological treatment There is no definitive treatment. Antibiotics, acyclovir, antihiatamine, colchicine, eostrogen, phenylbutazone, and steroids are some of the drugs that are used to treat the disease Pharmacological treatment
There is no definitive treatment. Antibiotics, acyclovir, antihiatamine, colchicine, eostrogen, phenylbutazone, and steroids are some of the drugs that are used to treat the disease
Acyclovir Acyclovir is used to treat Mollaret meningitis in selected patients in a dose of 10 mg/kg three times a day for 7-10 days. Some do not recommend the use of acyclovir as often the condition is benign and self limiting. Acyclovir
Acyclovir is used to treat Mollaret meningitis in selected patients in a dose of 10 mg/kg three times a day for 7-10 days. Some do not recommend the use of acyclovir as often the condition is benign and self limiting.

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