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Encephalitis

 

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    Background

    Inflammation of the brain.

    Causes

    Viral (50% of cases):

    • Commonest (in order): herpes simplex (HSV1 > HSV2), VZV, EBV.
    • Others: CMV, HIV seroconversion, measles, mumps, arboviruses (West-Nile, Japanese, tick-borne, St Louis), rabies.

    Autoimmune (20% of cases):

    • Often affects the medial temporal lobes, when it is known as 'limbic encephalitis'.
    • Often paraneoplastic.
    • Antibodies (and associations): anti-Hu (small cell lung cancer), anti-Ma2 (germ cell tumour of testes), anti-NMDAR (50% have ovarian tumour), anti-LGI1 (formerly 'anti voltage-gated potassium channel'; only 20% have cancer).

    Other causes:

    • Idiopathic (30% of cases).
    • Any bacterial meningitis can become a meningoencephalitis.
    • Spirochetes: Listeria, Lyme, syphilis.
    • TB
    • Protozoa: malaria, Toxoplasma.
    • Fungal: Aspergillus, Cryptococcus.

    Epidemiology

    • Annual incidence: 1/20,000.
    • Commonest under 1 years old or over 65.

  • Signs and symptoms

    • Initially non-specific: fever, headache, nausea, vomiting, malaise.
    • Neuro symptoms: seizures, odd behaviour or confusion, ↓level of consciousness, focal signs.
    • In addition to cerebrum, may also affect brainstem, dorsal roots (sensory), and autonomic nervous system, with an associated wide range of symptoms.

  • Investigations

    Take a careful history, including travel and bite exposure.

    Bloods:

    • Blood culture.
    • Serum viral PCR.
    • If suspected: toxoplasma IgM, malaria film.

    Image with MRI or contrast-enhanced CT:

    • Temporal lobe inflammation: usually HSV or autoimmune.
    • Meningeal irritation: meningoencephalitis.

    Special tests:

    • LP: ↑protein (most causes), ↑lymphocytes (viral, autoimmune), ↑PMNs (bacterial), ↓glucose (bacterial). Identify pathogen with viral PCR and Gram stain.
    • EEG: optional.

  • Management

    • Aciclovir IV stat to cover HSV. Continued for 14-21 days if HSV confirmed.
    • Consider ganciclovir for CMV if immunosuppressed.
    • Anticonvulsants for seizures.
    • Autoimmune encephalitis: immunosuppression (steroids, IVIg, plasma exchange) and treat any underlying cancer.
    • If infectious, notify public health authorities.

  • Complications and prognosis

    • Short term: seizures, ↑ICP, SIADH or diabetes insipidus.
    • Long-term: neurological complications are common, including motor and cognitive problems.
    • 10% mortality overall. For HSV, treatment reduces mortality from >50% to 20%.

  • Brain abscess

    Pathophysiology

    • A focal infection of brain tissue, comprising encapsulated pus, in contrast to the generalized infection/inflammation of encephalitis.
    • Source of pathogen: direct inoculation (penetrating trauma, neurosurgery), contiguous spread (mastoiditis, sinusitis, dental infection) or haematogenous (endocarditis, IVDU, right-to-left shunt).
    • Often polymicrobial. Staophylococci and Streptococci are common. In the immunosuppressed, consider Aspergillus, Toxoplasma, and Nocardia.

    Signs and symptoms

    • Classic triad (25%): headache (70%), fever (60%), focal neurology (60%).
    • Others: vomiting, confusion, lethargy, seizures.

    Investigations

    • CT/MRI head with contrast shows ring-enhancement.
    • Avoid LP due to risk of brainstem herniation.
    • Image-guided needle aspiration for culture, but do not delay antibiotics while waiting.

    Management

    • Ceftriaxone plus metronidazole IV for 6-8 weeks.
    • Aspiration or surgical drainage needed for most, though can trial antibiotics alone if small (<2 cm).

  • Acute disseminated encephalomyelitis (ADEM)

    Pathophysiology and epidemiology

    • Autoimmune CNS disease, defined by acute-onset encephalopathy, polyfocal neurology, and imaging evidence of multifocal demyelination.
    • Commoner in kids and young adults.

    Presentation

    • Encephalopathy: altered consciousness or behaviour.
    • Polyfocal neurology e.g. weakness, ataxia, gait abnormality, cranial nerve palsies, visual problems, seizures, spinal deficits.
    • Non-specific symptoms: fever, headache, nausea/vomiting.
    • ⅔ have a recent (<4 weeks) history of infection, which is thought to be a trigger.

    Investigations

    • MRI: multiple, large white matter lesions, usually brain, but spine affected in 1/3.
    • CSF: ↑WBC and ↑protein (both around 50% sensitive).
    • No definitive diagnostic test.

    Management

    • Steroids, IV then oral taper.
    • IVIg or plasma exchange 2nd line.

    Prognosis

    Most recover fully, but 25% develop a relapsing demyelinating disease (multiphasic ADEM, MS, or NMO).

Labels: health tips, disease condition

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If u have any doubt let me know.

DISEASE CONDITIONS LIST THAT IMPROVED KNOWLEDGE.

Newborn Baby Assessment

Baby check at birth and 6 weeks  Check notes and get equipment ready:   Measuring tape. Ophthalmoscope Sats probe. In notes, look at full details of pregnancy and birth, including Apgar scores at 1 and 5 minutes. Observation: Colour: pink/red, pale, jaundiced. Any rash? Erythema toxicum is a self-limiting rash of red papules and vesicles, surrounded by red blotches which sometimes give a halo appearance. Usually occurs between 2 days and 2 weeks. Behaviour and mood. Movements. Face: dysmorphism? Head: Feel fontanelle (bulging? sunken?) and sutures. Note that posterior fontanelle closes at 1-2 months, and anterior at 7-19 months. Measure circumference at widest point; take the highest of 3 measurements. Looking for hydrocephalus and microcephaly. Eyes: check red reflex with ophthalmoscope. Feel inside top of mouth with little finger for cleft palate. Also gives you the sucking reflex. Inspect ears to see if they are low-set (below eye level), have any tags or lumps, and check behind the
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immunization schedule

Infant immunisations  2 months 5-in-1 DTaP/IPV/Hib – diptheria, tetanus, pertussis, polio, Hib – dose 1. Pneumococcal conjugate vaccine (PCV) dose 1. Rotavirus dose 1. Live, oral virus. MenB dose 1. 3 months 5-in-1 dose 2. MenC dose 1. Rotavirus dose 2. 4 months 5-in-1 dose 3. PCV dose 2. MenB dose 2. 12 months MMR dose 1. MenC dose 2 + Hib dose 4 (combined). MenB dose 3. PCV dose 3. Hepatitis B if they have risk factors. Toddler immunisations Flu vaccine Annual, live attenuated nasal spray flu vaccine in September/October at age 2-7. Kids with asthma and other chronic diseases like CF will continue to get this through childhood and beyond. Contraindicated in severe egg allergy, immunosuppression (inc. steroids in past 2 weeks), and severe asthma or active wheeze. Alternative form can be given. Postpone in those with heavy nasal congestion. 3.5 years 4-in-1 DTaP/IPV: dip, tet, pertussis, polio pre-school boost. MMR dose 2. Teenager immunisations 12 years HPV: Girls only. Parental conse
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Hypertension (HTN)

Background     Causes Primary causes: Essential HTN (i.e. idiopathic). Commonest cause. Non-pathologically raised during pain or anxiety (including white coat HTN). However, this may suggest underlying problem so consider following up. Kidney diseases (80% of secondary HTN): Chronic kidney disease. Renal artery stenosis: due to atherosclerosis or fibromuscular dysplasia. Latter most commonly occurs in young women, but even then essential HTN is still commoner. Endocrine: Conn's Cushing's Pheochromocytoma Acromegaly Hyperparathyroidism Other: Obstructive sleep apnoea Pregnancy or pre-eclampsia. Coarctation of the aorta. Medication: CE-LESS ('see less'): C yclosporin E strogen (OCP) L iquorice E PO S teroids S ympathomimetics: α-agonists, dopamine agonists, cocaine, amphetamines, and nasal decongestants such as ephedrine. Signs and symptoms Symptoms of HTN itself are rare, and occur only in severe disease. They include heada
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