Infectious disease
1 / 30

Infectious Disease - PowerPoint PPT Presentation

  • Updated On :

Infectious Disease. Hugh Mc Gann Department of Infectious Diseases Seacroft Hospital. Assessment of patients with infections. History Examination Investigations. History. Specific symptoms e.g. fever, rigors, sweats Risk factors for infection Travel Infectious contacts Occupation

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Infectious Disease' - EllenMixel

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
Infectious disease l.jpg

Infectious Disease

Hugh Mc Gann

Department of Infectious Diseases Seacroft Hospital

Assessment of patients with infections l.jpg
Assessment of patients with infections

  • History

  • Examination

  • Investigations

History l.jpg

  • Specific symptoms e.g. fever, rigors, sweats

  • Risk factors for infection

    • Travel

    • Infectious contacts

    • Occupation

    • Pets/birds

    • Sex/needles

    • Time since exposure/how long unwell

    • Previous medical problems/medications

Investigations 1 l.jpg
Investigations 1

  • Baseline blood tests

    • Inflammatory markers: PV, ESR,CRP

    • LFTS

  • Culture things

    • Pus

    • Blood

    • Urine

    • Sputum

    • CSF

    • Biopsies

  • Investigations 2 l.jpg
    Investigations 2

    • Serology: Measure antibodies to specific infections IgG/IgM

    • Molecular methods

      • DNA amplification-PCR

  • Radiology

    • Plain X-rays

    • Ultrasound

    • CT/MRI

    • Isotope scans

  • Immunity 1 l.jpg
    Immunity 1

    • Innate Immunity

      • General or non specific host defences which provide the initial protection against microbes

        • Physical: skin, mucous membranes, intestinal tract, eye

        • Colonisation resistance by the normal flora

        • Mechanical removal: sneezing, coughing

        • Non-specific immune system: phagocytosis, complement, cytokines, natural killer cells

    Immunity2 l.jpg

    • Specific immunity

      • Characterised by antigen specificity, memory and heightened response on subsequent antigen exposure

        • Humoral immunity: B cell receptors-Antibodies-activation of complement by classical pathway

        • Cell mediated immunity: T cell receptors-cytotoxic T cells

    Vaccination l.jpg

    The act of artificially inducing immunity or providing protection from disease

    Vaccines have led to the global eradication of smallpox, elimination of polio from western world and reduced incidence of many common disease


    Vaccination 2 l.jpg
    Vaccination 2 protection from disease

    • Active Immunisation

      • A vaccine which stimulates body’s immune system to produce antibodies or cell mediated immunity

        • Live (attenuated infectious agents) Immunological response similar to that of natural infection. Life long immunity with one dose

        • Promote cell mediated immunity

        • MMR, polio(o), yellow fever

    Vaccination 3 l.jpg
    Vaccination 3 protection from disease

    • Active Immunisation

      • Inactivated (contain components of the organism or exotoxin) Diptheria, whooping cough, tetanus, HiB

      • Need repeated vaccinations and boosters to obtain high level/long lasting immunity

      • 1st(/2nd) injection produces slow antibody response-IgM

      • Subsequent injections give accelerated and higher level of antibodies IgG

    Vaccination 4 l.jpg
    Vaccination 4 protection from disease

    • Passive immunisation: short term protection by injecting human immunoglobulin. Immediate protection but only for a few weeks

      • Human normal immunoglobulin

        • Hepatitis A, measles

      • Specific immunoglobulin

        • Varicella zoster, hepatitis B

    Vaccination 5 l.jpg
    Vaccination 5 protection from disease

    • Childhood vaccine schedule

      • 3 doses at 2+3+4 months: HiB, DTP, Polio, Meningococcus group C

      • 12-15 months: MMR

      • 3-5 years: DT, Polio, MMR

      • 10-15 years DT, P, Polio

      • BCG

    Herpes viruses l.jpg
    Herpes viruses protection from disease

    • Herpes Simplex Virus 1and 2

    • Varicella Zoster

    • Cytomegalovirus

    • Epstein Barr (Infectious Mononucleosis)

    • Human Herpes Virus Type 6 and 7

    • Human Herpes Virus Type 8(Kaposi sarcoma associated herpes virus)

    Herpes simplex l.jpg
    Herpes Simplex protection from disease

    • HSV 1 and 2 cause clinically indistinguishable infection.

    • Primary infection: systemic illness

      • Gingivostomatitis and pharyngitis

      • Genital infection

    • Reactivation:

      • Genital HSV 2 more likely to reactivate

      • Oral-labial HSV 1 more likely to reactivate

    Varicella zoster virus 1 l.jpg
    Varicella Zoster Virus 1 protection from disease

    • Causes 2 distinct clinical diseases

    • Chicken Pox(varicella zoster) This is the primary infection.

      • Very contagious

      • Incubation period 10-14 days

      • Benign illness in children

      • Fever, vesicular rash, this then pustulates and scabs

    Varicella zoster virus 2 l.jpg
    Varicella Zoster virus 2 protection from disease

    • Shingles (Herper Zoster) reactivation of VZV which is latent in the dorsal root ganglia

      • Occurs in those who have had chickenpox, usually elderly

      • Vesicular rash with dermatomal distribution

      • H.Z. ophthalmicus, maxillary/mandibular V

      • Ramsay Hunt syndrome

    Infectious mononucleosis 1 l.jpg
    Infectious Mononucleosis 1 protection from disease

    • Epstein Barr virus

    • Acute illness with sore throat (bilateral exudative tonsillitis), fever and lymphadenopathy

    • Ampicillin causes a rash in 90-100%

    • Palatal petechiae in up to 60%

    • Abnormal LFTs in 90%

    Infectious mononucleosis 2 l.jpg
    Infectious Mononucleosis 2 protection from disease

    • Usually resolves within 2-3 weeks

    • Diagnosis by GFST (Paul-Bunell or monospot which detect heterophile antibodies

    • Atypical lymphocytes on blood film

    Childhood rashes l.jpg
    Childhood Rashes protection from disease

    • Measles

    • Rubella

    • Scarlet Fever

    • Erythema Infectiosum

    • Exanthem Subitum

    Measles l.jpg
    Measles protection from disease

    • Marked decrease in incidence since vaccine

    • Highly infectious, spread by droplets from respiratory secretions

    • Incubation period of 10 - 14 days

    • Diagnosis, clinical, confirmed by specific IgM in blood/saliva

    • Complications: pneumonia, encephalitis

    Measles clinical features l.jpg
    Measles Clinical features protection from disease

    • Prodrome, malaise, fever, conjunctivitis and coryzal symptoms

    • Koplik’s spots: bluish grey grains on a red base on buccal mucosa opposite 2nd molars

    • Rash: purplish maculopapular, initially on the face, extends down the body

    • Illness lasts 7-10 days

    Scarlet fever l.jpg
    Scarlet Fever protection from disease

    • Streptococcal infection- Group A Strep.

    • Streptococcal strain wgich produces an erythrogenic toxin

    • Pharyngitis

    • Rash on 2nd day of illness

      • Flushed face(circumoral pallor)

      • Strawberry tongue

    Rubella l.jpg
    Rubella protection from disease

    • Mild illness, often subclinical

    • Rubella virus first isolated in 1962, recognised clinically from 19th century

    • Spread: droplets from respiratory secretions

    • Usually primary school children.

    • Infection in pregnancy can cause foetal infection (congenital defects, foetal death)

    Rubella clinical features l.jpg
    Rubella, Clinical Features protection from disease

    • Incubation period 10-18 days

    • Rash: pink macular, face and trunk on day 1, limbs day 2, disappears day 3/4

    • Lymphadenopathy: posterior cervical and sub occipital nodes

    • Conjunctival and pharyngeal injection

    • Diagnosis by specific rubella IgM

    Erythema infectiosum l.jpg
    Erythema Infectiosum protection from disease

    • Often called slapped cheek or fifth disease

    • Caused by Parvovirus B19

    • Facial rash sometimes preceded by mild fever

    • Rash: slapped cheek appearance, resolves in about 1 week but can recur with exposure to heat

    Exanthem subitum l.jpg
    Exanthem subitum protection from disease

    • Called roseola infantum or sixth disease

    • Caused by HHV-6

    • Benign illness of infants/children

    • Rash preceded by 3-4 days of high fever, upper respiratory symptoms

    • Rash: maculopapular on trunk/limbs

    Mumps l.jpg
    Mumps protection from disease

    • Viral illness mostly in children/adolescents

    • Spread by droplets, incubation 2-4 weeks

    • Prodrome of fever, malaise, headache

    • Parotid gland enlargement (lifts ear up and out) usually bilateral, unilateral in 25%

    • May involve other salivary glands

    • Complications: orchitis and meningitis

    Whooping cough 1 l.jpg
    Whooping Cough 1 protection from disease

    • Bordetella Pertussis

    • Higher incidence and increased severity in girls

    • Disease of childhood but now mostly seen in adults because of vaccination

    • Disease most severe in infants

    • Incubation period 1-3 weeks

    Whooping cough 2 l.jpg
    Whooping Cough 2 protection from disease

    • Catarrhal phase: malaise, low grade fever, runny nose and eyes

    • Paroxysmal phase: typical cough-Whoop

    • Blood tests show high white cell count

    • Complications: secondary infection, physical sequelae of paroxysms of coughing