What is meningitis?
Inflammation/infection of meninges
What is the classical triad of meningitis?
Fever
Neck stiffness
Altered mental state
What is the presentation of meningitis?
Progressive headache Fever MEningism Cerebral dysfunction Cranial nerve palsy Seizures Focal neurological deficits Petechial skin rash
What is the differential diagnosis of meningitis?
Infective Sarcoidosis NSAIDs, IVIG Metastatic haematological
What are the causes of infective meningitis?
Bacterial
Viral
Fungal
What investigations should be done for meningitis?
Blood cultures
LP
Imaging only if LP contraindicated
What would be find on CSF in bacterial meningitis?
Increased opening pressure
High WBC, mainly neutrophils
Reduced glucose
High protein
What would be found on CSF in viral meningitis?
normal/increased opening pressure
High white cell count, esp lymphocytes
Normal glucose
Slightly increased protein
what is normal CSF glucose?
60% blood glucose
When should blood and CSF stains be carried out for meningitis?
If pyrexial
What is encephalitis?
Inflammation/infection of the brain substance
What are the clinical features of encephalitis?
Slower onset Flu like Headache and fever With or without meningism Progressive cerebral dysfunction Seizures Focal signs and symptoms
How can encephalitis be differentiated from meningitis?
Slower onset
Cerebral dysfunction more common
What is the differential diagnosis for encephalitis
Infective Limbic encephalitis Hepatic, uraemia or hyperglycaemic causes Metastases or paraneoplasm Migraine Post octal Autoimmune encephalitis
What are the most common causes of encephalitis?
Viral- herpes simplex
Autoimmune
What are the causes of infective encephalitis?
Herpes simplex
Abovirus encephalitides
Enterovirus
How is HSV encephalitis diagnosed?
PCR of CSF for viral DNA
How is HSV encephalitis treated?
Aciclovir on clinical suspicion
What investigations are done for encephalitis?
Blood cultures
CT/MRI
LP
EEG
What is myelitis?
Inflammation/infection of the spinal cord
What are the contraindications for LP?
Focal neurological deficit New onset seizures papilloedema GCS <10 Severely immunocompromised state Raised ICP
Why is raised ICP a contraindication for LP?
Can cause distortion and herniation of brain contents through foramen
What is a brain abscess?
Localised area of pus within the brain
What is a subdural empyema?
Thin layer pf pus between dura and arachnoid maters over surface of brain
What are the clinical features of brain abscess and subdural empyema?
Fever, headache Focal signs and symptoms Signs of raised ICP Meningism Features of underlying source
What is the differential for brain abscess/empyema?
Any focal lesion
Subdural haematoma
What are the causes of brain abscess/empyema?
Penetrating head injury
Spread from adjacent infection
Blood borne infection
Neurosurgical procedure
How are brain abscesses and empyema diagnosed?
Imaging
Blood cultures
Biopsy of pus
How is a brain abscess managed?
Surgical drainage
Antibiotics- penicillin for streps, metronidazole for anarobes
What bacteria is responsible for Lyme disease?
Borrelia burgdorferi
What is stage 1 of Lyme disease?
Early localised infection
What are the signs of stage 1 Lyme disease?
Erythema migrans
Flu like symptoms
What is stage 2 Lyme disease?
Early disseminated infection
One or more organ systems involved
What are the most common systems involved in stage 2 Lyme disease?
Musculoskeletal and neurological
What are the symptoms of neurological involvement in stage 2 Lyme disease?
Mononeuropathy Mononeuritis multiplex Painful radiculoneuropathy Cranial neuropathy Myelitis Meningo-encephalitis
What is stage 3 Lyme disease?
Chronic infection
What are the symptoms of neurological involvement of stage 3 Lyme disease?
Mononeuropathy Mononeuritis multiplex Painful radiculoneuropathy Cranial neuropathy Myelitis Meningo-encepgalitis Subacute encephalopathy Encephalomyelitis
What investigations are carried out for Lyme disease?
Serological tests CSF lymphocytosis PCR of CSF MRI brain/spine for CNS involvement Nerve conduction studies/EMG for PNS involvement
What is the treatment of Lyme disease?
Prolonged antibiotic treatment
What systems can be involved in Lyme disease?
Skin Rhematological Neurological/neuropsychiatric Cardiac Opthamological
What is the 3 stage presentation of syphilis?
Primary
Secondary
Latent
What investigations are done for neurosyphilis?
Antibody tests
Increased CSF lymphocytes
Intrathecal antibody production
PCR of CSF
What is the treatment of neurosyphilis?
High dose penicillin
What causes poliomyelitis?
Poliovirus types 1, 2 and 3
What does paralytic poliomyelitis infect?
Anterior horn cells of LMNs
What does paralytic poliomyelitis cause?
Asymmetric flaccid paralysis, esp of legs
No sensory features
What is included in the poliovirus?
All 3 poliovirus
What is rabies?
Acute infectious disease of CNS
How is ladies transmitted to humans?
Bite
Salivary contamination of open lesion
How does the rabies virus progress/
Enters PNS and travels to CNS
What are the signs f rabies?
Ascending paralysis and encephalitis
How is rabies diagnosed?
Culture
Detection
Serology
Who is the rabies immunisation given to?
Bat handlers
Handlers of imported animals
Selected travellers to exotic areas
What is the post exposure treatment for possibles rabies?
Wah wound
Give active rabies immunisation
Give human rabies immunoglobulin if high risk
What happens in tetanus?
Toxins act at neuromuscular junction and block inhibition of motor neurones, causing rigidity and spasm
How is tetanus prevented?
immunisation
Penicillin and immunoglobulin for high risk wounds
What causes botulism?
Clostridium botulinum
What happens in botulism?
Neurotoxin binds irreversibly to presynaptic membranes pf peripheral neuromuscular and autonomic nerve junctions
The toxin binding blocks Ach release
How do you recover from botulism?
Sprouting new axons
What arebthe 3 modes of infection in botulism?
Intestinal colonisation
Food borne
Wound
What is the presentation of botulism?
Descending symmetrical flaccid paralysis
respiratory failure
Autonomic dysfunction
Pupillary dilation
What is the investigation for botulism?
Nerve conduction studies
Bioassay for toxin in blood
Culture from wound
What is the treatment of botulism?
Anti-toxin
Penicillin/metronidazole
Radical wound debridement
What are the types of Creutzfeldt Jakob disease?
Sporadic
New variant
Familial
Acquired
What are the clinical features of sporadic CJD?
Insidious onset Early behavioural abnormalities Rapidly progressive dementia Myoclonus Motor abnormalities Cortical blindness Seizures
What motor abnormalities occur in sporadic CJD?
Cerebellar ataxia
Tremor, rigidity, bradykinesia, dystonia
Weakness, spasticity, hyper-reflexia
What is the differential diagnosis for sporadic CJD?
Alzheimer’s with myoclonus
Subacute sclerosis panencephalitis
CNS vasculitis
Inflammatory encephalopathies
What are the features of new variant CJD?
Younger onset
Prominent early behavioural changes
Longer course
What are the investigations for CJD?
MRI
EEG
Protein in CSF