Infection Flashcards

Question

What does bacillus mean?

Answer 1

Rod shaped bacteria

Answer 2

Parvovirus 19

Answer 3

Adenovirus BK virus Human papilloma virus JC virus

Answer 4

Herpes virus Hepatitis B Molluscum contagiosum

Answer 5

``` Coxsackievirus Echovirus Enterovirus Hepatitis A & E Norovirus ```

Answer 6

``` HIV Hepatitis C Rubella virus Encephalitis viruses Yellow fever virus West Nile virus ```

Answer 7

Ebola, Lassa, Marburg Influenza, Parainfluenza Respiratory syncytial virus (RSV)

Answer 8

``` Single stranded Non enveloped DNA virus Child hood rash Slap cheek syndrome ```

Answer 9

``` Double stranded Non enveloped DNA virus Respiratory Common cold Pneumonia ```

Answer 10

``` Double stranded Non enveloped DNA virus Polyomavirus Immunosuppressed Asymptomatic ```

Answer 11

``` Double stranded Non enveloped DNA virus Keratinocytes, mucous membranes Benign papillomas/cancers, warts STDs ```

Answer 12

``` Double stranded Non enveloped DNA virus Polyoma virus Immunosuppression ```

Answer 13

``` Double stranded Enveloped DNA virus STD Hepstein Barr ```

Answer 14

``` Double stranded Enveloped DNA virus Liver Flu like symptoms Unprotected sex Sharing needles ```

Answer 15

``` Double stranded Enveloped DNA virus Small firm raised papules on skin Not painful but itchy Highly contagious- skin to skin ```

Answer 16

``` Single stranded Positive Icosahedral Non enveloped Enterovirus Digestive tract Unwashed hands and contaminated surfacesFlu symptoms Red blisters Haemorrhagic conjunctivitis ```

Answer 17

``` Single stranded Positive Icosahedral Non enveloped GI tract Liver failure Myocarditis ```

Answer 18

``` Single stranded Positive Icosahedral Non enveloped Genus ```

Answer 19

``` Single stranded Positive Icosahedral Non enveloped Virus found in stool Liver E in particular - pets/eating meat ```

Answer 20

``` Single stranded Positive Icosahedral Non enveloped High temp, stomach cramps, headache, aching limbs, dehydration, vomiting, diarrhoea Very contagious ```

Answer 21

``` Single stranded Positive Icosahedral of helical Enveloped Lentivirus (AIDS) Affects helper T cells (CD4+) ```

Answer 22

``` Single stranded Positive Icosahedral of helical Enveloped Liver Conc in blood Blood to blood contact ```

Answer 23

``` Single stranded Positive Icosahedral of helical Enveloped First week of pregnancy German/ 3 day measles ```

Answer 24

Single stranded Positive Icosahedral of helical Enveloped (Japanese, St. Louis, tick borne, Venezuelan, equine) Inflammation of brain Most commonly caused by herpes simplex virus

Answer 25

``` Single stranded Positive Icosahedral of helical Enveloped Fevers, chills, loss of appetitie nausea, muscle pain, headache Bite of female mosquito Vaccine exists Flavivirus genus ```

Answer 26

``` Single stranded Positive Icosahedral of helical Enveloped Flavivirus genus Mosquito Africa--> NY --> USA No vaccine ```

Answer 27

``` Single stranded Negative Helical Enveloped Vomiting Diarrhoea Rash Deceased liver and kidney function Fruit bats ```

Answer 28

``` Single stranded Negative Helical Enveloped Flu symptoms ```

Answer 29

``` Single stranded Negative Helical Enveloped Lower respiratory tract infections ```

Answer 30

``` Double stranded Icosahedral Non enveloped Severe diarrhoea among infants Stools- virus passes out ```

Answer 31

``` Staph aureus Coagulate -ve staph Alpha haemolytic streptococci Beta haemolytic streptococci (inc. strep pyogenes) Streptococcus pneumoniae Enterococcus faecalis ```

Answer 32

Neisseria meningitidis Neisseria gonorrhoea Mortadella cattarhalis Acinetobacter baumannii

Answer 33

Listeria monocytogenes Bacillus anthracis Bacillus cereus

Answer 34

``` Escherichia coli Klebsiella pneumoniae Proteus species Salmonella typhi Pseudomonas aeruginosa Haemophilus influenzae ```

Answer 35

``` Pathogen Patient Mechanism of infection Infection Management Outcome ```

Answer 36

Virus Bacterium (prokaryotic) Fungus - yeast, mould (eukaryotic) Parasites - protozoa, helminthology (worm) (eukaryotic)

Answer 37

Person - age, gender, physiological state, pathological state, social factors Time - calander time, relative time Place - current, recent

Answer 38

``` Contiguous spread (direct) Inoculation Haematogenous Ingestion Inhalation Vector Vertical transmission ```

Answer 39

Attachment --> toxin production --> host damage Attachment --> interaction with host defences --> host damage Attachment --> interaction with host defences --> inflammation --> host damage

Answer 40

History Examinations Investigations Treatment - Supportive - symptom relief, physiological restoration - Specific - antimicrobials, surgery- drainage, debridement, dead space removal Infection prevention - hospital and community - prevent infection transmission to - other patients, staff and contacts

Answer 41

Spectrum of Cured to Death with disability and chronic infection being intermediates

Answer 42

Antibacterial agents Antifungal agents Antiviral agents Antiprotozoal agents

Answer 43

``` Bactericidal/ bacteriostatic Spectrum- broad vs narrow Target site (mechanism of action) Chemical structure (antibacterial class) ```

Answer 44

Antibiotic kills organism completely

Answer 45

Antibiotic inhibits the organism but it can come back

Answer 46

Groups together drugs with the same basic function and mechanism of action

Answer 47

``` Selectively toxic Few adverse effects Reach site of infection Oral/ IV formulation Long half life (infrequent dosing) No interference with other drugs ```

Answer 48

``` Those that affect: Cell wall synthesis Cell membrane function Protein synthesis Nucleic acid synthesis ```

Answer 49

B-lactams (penicillin, cephalosporins) | Glycopeptides (vancomycin)

Answer 50

Polymixins (colistin)

Answer 51

Tetracyclines Aminoglycosides (gentamicin) Macrolides (erythromycins)

Answer 52

Quinolones (ciprofloxalin, trimethoprim, rifampcin)

Answer 53

Cross linkage between peptidoglycan - gives cell wall rigidity Achieved by penicillin binding protein Penicillin gets in and blocks penicillin binding protein so protein can no longer bind to chains of amino acids- no cross linkage

Answer 54

Sits on peptidoglycan chains and stops penicillin binding protein from binding (acts at an earlier stage than B- lactams)

Answer 55

Interupting cell wall synthesis

Answer 56

Interrupting cell membrane function

Answer 57

Drug inactivating enzymes- B-lactamases, aminoglycoside enzymes Altered target- target enzyme has lowered affinity for antibacterials e.g. resistance to meticillin, macrolides and trimethoprim Altered uptake- reduced ability of antibiotic to get close to bacteria; decreased permeability (e.g. B-lactams) or increased efflux (e.g. Tetracyclines)

Answer 58

Chromosomal gene mutation- bacteria undergo spontaneous gene mutation conferring resistance; when exposed to antibiotics, bacterial cell with resistance survives and multiplies Horizontal gene transfer- plasmid to plasmid or plasmid to chromosome; genetic material moves from one organism to another by conjugation, transduction and transformation

Answer 59

Disc testing- impregnate antibody into paper filter disc and observe bacterial growth- organism won't grow where there is sufficient antibiotic to inhibit its growth Minimum inhibitory concentration- more mathematical, lots of test tubes with a range of antibiotic concentrations and the same concentration of organism- organism growth is monitored

Answer 60

Penicillins Cephalosporins Carbapenems Monobactams

Answer 61

Affect cell wall synthesis

Answer 62

B-lactam, penicillin Affect cell wall synthesis Mainly active against streptococci

Answer 63

B-lactam, penicillin Affect cell wall synthesis Mainly active against streptococci

Answer 64

B-lactam, penicillin Affect cell wall synthesis Mainly active against streptococci Also active against gram negatives

Answer 65

B-lactam, penicillin Affect cell wall synthesis Active against staphylococci and streptococci

Answer 66

B-lactam, penicillin Affect cell wall synthesis Active against staphylococci, streptococci, anaerobes and Gram negatives

Answer 67

B-lactam, penicillin Affect cell wall synthesis Active against staphylococci, streptococci, anaerobes, and High activity against gram negatives including pseudomonas

Answer 68

B-lactam,Cephalosporin (Generations with high gram negative and low gram positive activity; broad spectrum but no anaerobe activity: concern over association with C. difficile)

Answer 69

1st generation cephalosporin, B-lactam

Answer 70

2nd generation cephalosporin, B-lactam

Answer 71

3rd generation cephalosporin, B-lactam

Answer 72

3rd generation cephalosporin, B-lactam Blindness/ meningitis Good activity in CSF

Answer 73

3rd generation cephalosporin, B-lactam

Answer 74

Carbapenem, B-lactam Very broad spectrum (including anaerobes) Active against most(not all) gram negatives Generally safe in penicillin allergy, other than anaphylaxis

Answer 75

Monobactam, B-lactam

Answer 76

Affect Cell wall synthesis

Answer 77

Glycopeptides Affects cell wall synthesis Active against most Gram positive (not gram negative) Some enterococci resistant (VRE) Resistance in staphs is rare Not absorbed (oral for C.difficile only) Therapeutic drug monitoring (TDM) required as there is a narrow therapeutic window - give enough, not too much, toxicity

Answer 78

Similar activity to vancomycin, but much easier to administer Glycopeptides Affects cell wall synthesis Active against most Gram positive (not gram negative) Some enterococci resistant (VRE) Resistance in staphs is rare Not absorbed (oral for C.difficile only) Therapeutic drug monitoring (TDM) required as there is a narrow therapeutic window - give enough, not too much, toxicity

Answer 79

Affecting protein synthesis

Answer 80

Similar, broad spectrum Both oral only Specific use in penicillin allergy usually from gram positive Active in atypical pathogens in pneumonia Active against chlamidya and some Protozoa Shouldn't be given to children younger than 12 years

Answer 81

Affecting protein synthesis

Answer 82

Aminoglycosides Most common agent Profound activity against gram negative Good activity in blood and urine Potentially nephrotoxic/ototoxic Therapeutic drug monitoring (TDM) required- toxicity to kidney Generally reserved for sever gram negative sepsis

Answer 83

Affecting protein synthesis

Answer 84

Macrolides Affects protein synthesis Well distributed including intracellular penetration Alternative to penicillin for mild gram positive infections Also active against atypical respiratory pathogens

Answer 85

Affects nucleic acid synthesis

Answer 86

``` Quinolone Affects nucleic acid synthesis Commonest example Inhibits DNA gyrase (coiling of nucleic acid) Very active against gram negatives Also active against atypical pathogens Increasing resistance and risk of CDI ```

Answer 87

Inhibitors of frolic acid synthesis Trimethoprim used alone in UK for UTIs When combined with sulphamethoxazole- cotrimoxazole, used to treat PCP (pneumocystitis pneumonia) , has activity against MRSA

Answer 88

Azoles | Polyenes

Answer 89

Antifungal Active against yeasts, and or moulds Inhibit cell membrane synthesis

Answer 90

``` Antifungal Inhibits cell membrane synthesis Used to treat candida Hra, vori, posaconazol Also active against aspergillus ```

Answer 91

Antifungals | Inhibit cell membrane function

Answer 92

Antifungals Inhibit cell membrane function Nystatin for topical treatment of candida Amphotericin for IV treatment of systemic fungal infections (e.g. Aspergillus)

Answer 93

Aciclovir | Oseltamivir (tamiflu)

Answer 94

Antiviral When phosphorylates inhibits viral DNA polymerase Herpes simplex - genital herpes, encephalitis Varicella zoster - chicken pox and shingles

Answer 95

Antifungal Inhibits viral neuraminidase Influenza A & B

Answer 96

``` Antibacterial and antiprotozoal agent Active against anaerobic bacteria Also active against Protozoa - amoebae (dysentery and systemic) - giardia (diarrhoea) - trichomonas (vaginitis) ```

Answer 97

Neisseria Meningitidis

Answer 98

Cells and organs that contribute to immune defences against infections and non infectious conditions (harmless substances)

Answer 99

When the pathogen succeeds in evading and / or overwhelming the hosts immune defences

Answer 100

Pathogen recognition - cell surface and soluble receptors Containing / eliminating the infection - killing and clearance mechanisms Regulating itself - minimum damage to host (resolution) Remembering pathogens - preventing disease from recurring

Answer 101

Innate | Adaptive

Answer 102

Physical barriers Physiological barriers Chemical barriers Biological barrier

Answer 103

Skin (SA 1-2m^2) Mucous membrane (mouth, resp tract, GI tract, urinary tract) Bronchial cilia

Answer 104

Diarrhoea- food poisoning, allergies Vomiting- food poisoning, hepatitis, meningitis Coughing- pneumonia Sneezing- sinusitis

Answer 105

Low pH - skin(5.5) stomach(1-3) vagina(4.4) Antimicrobial molecules -IgA (tears, saliva)- binds specifically to microorganisms and prevents it from attaching to mucous membrane -Lysozyme (sebum, perspiration, urine) -Mucous (mucous membrane) -Beta defensins (epithelium) -Gastric acid and Pepsin

Answer 106

Normal flora - non pathological microbes - strategic locations- nasopharynx, mouth/throat, skin, GI tracts, vagina, (lactobacillus spp) - absent in internal organs Benefits - compete with pathogens for attachement sites and resources, produce antimicrobials chemicals, synthesise vitamins (K, B12 and others)

Answer 107

``` Staphylococcus aureus Staphylococcus epidermidis Streptococcus pyogenes Candida albicans Clostridium perfringens ```

Answer 108

Streptococcus pneumoniae Neisseria meningitidis Haemophilius species

Answer 109

-->Normal flora can be displaced from its normal location to a sterile location -breaching skin integrity (skin loss, burns; surgery; injection drug users; IV lines) -fecal oral route (food borne infection) -fecal perineal urethral route (UTI) -poor dental hygiene/ dental work (dental extraction, gingivitis, flossing) (common cause of harmless bacteraemia) Serious infection in high risk patients -asplenic/hyposplenic -damaged prosthetic valves -previous infective endocarditis -antibiotic prophylaxis - -> Normal flora overgrows and becomes pathogenic when host becomes immunosuppressed - diabetes, AIDS, malignant diseases, chemotherapy (neutrophils) - -> When normal flora is depleted by antibiotics - intestine --> severe colitis (clostridium difficile) - vagina --> thrush (Candida albicans)

Answer 110

Phagocytes | Chemicals

Answer 111

Phagocyte-microbe interaction - RECOGNITION - -microbial structures: Pathogen Associated Molecular Patterns (PAMPs) - carbohydrates, lipids, proteins, nucleic acid - -phagocytes: Pathogen Recognition Receptors - Toll like receptors - -opsonisation of microbes: coating proteins called opsonins that bind to the microbial surfaces leading to enhanced attachment of phagocytes and clearance of microbes - ENGULFMENT - DEGRADATION OF INFECTIOUS MICROBES - -phagocyte intracellular killing mechanisms - --O2 dependent - ROS via NADPH oxidase - --O2 independent - lysozyme, lactoferrin/transferrin, cationic proteins, proteolytic and hydrolytic enzymes

Answer 112

Complement proteins- C3b C4b Antibodies- IgM, IgG Acute phase proteins - CRP, mannose binding pectin (MBL) Essential in clearing encapsulated bacteria - neisseria meningitidis - streptococcus pneumoniae - haemophiliis influenzae b

Answer 113

Complement system- 20 serum proteins, most important C1-C9 - 2 activating pathways (actually 3) - - alternative pathway - initiated by cell surface microbial constituents - - MBL pathway - initiated when MBL binds to mannose containing residues of proteins found on Salmonella spp Candida albicans Cytokines - phagocytosis - chemo attraction, phagocyte activation, inflammation - antimicrobials actions of macrophage derived TNF alpha, IL-1, IL-6 - - liver (opsonins) CRP, MBL (complement activation) - - bone marrow - neutrophil mobilisation - - inflammatory actions - vasodilation, vascular permeability, adhesion molecules, attraction of neutrophils - -hypothalamus- increased body temp

Answer 114

C3a and C5a - recruitment of phagocytes C3b and C4b - opsonisation of pathogens and inflammation C5 - C9 - killing of pathogens in the Membrane Attack Complex

Answer 115

Infection --> microbial toxins (LPS) --> overreaction of TLR4 receptor --> overreaction of complement (neutrophils, endothelium and monocytes) --> excessive systemic inflammatory response --cytokines shower, coagulopathy, vasodilation, capillary leak (tissue organ perfusion)--> sepsis and multi organ failure Clinical problems start when phagocytosis is reduced - deceased spleen function (asplenic, hyposplenic) - decreased neutrophil number (cancer chemo, certain drugs, leukaemia and lymphoma) - decreased neutrophil function (chronic granulomatous disease, no resp burst) - chediak higashi syndrome (no phagolysosomes formed)

Answer 116

Infections arising as a consequence of providing healthcare So in hospital patients- infection is not present nor incubating at the time of admission -e.g. Onset is at least 48 hours after admission Can also include infections in hospital visitors and health workers

Answer 117

Blood borne: Hepatitis B, C, HIV Norovirus Chicken pox Influenza

Answer 118

``` Staphylococcus aureus (inc. MRSA) Clostridium Difficile Escherichia Coli, Klebsiella Pseudomonas pneumoniae, aeruginosa Mycobacterium TB ```

Answer 119

Candida albicans | Aspergillus species

Answer 120

Malaria plasmodium falciparum

Answer 121

``` Extremes of age Obesity/ malnourished Diabetes Cancer Immunosuppression Smoker Surgical patient Emergency admission ```

Answer 122

Optimise patients condition- smoking, nutrition, diabetes Antibiotic microbial prophylaxis Skin preparation Hand hygiene

Answer 123

MRSA screens Mupirocin nasal ointment Disinfectant body wash

Answer 124

Physical barriers- isolation of infected patients, protection of susceptible patients

Answer 125

Healthy- disease free and vaccinated | Good practice- good clinical techniques, hand hygiene, PPE, antimicrobial prescribing

Answer 126

Built environment- space, layout, toilets, wash hand basins Appropriate furniture and furnishings Cleaning- disinfectants/ steam cleaning/ H2O2 vapour Medical devices- single use equipment, sterilisation, decontamination Appropriate kitchen and ward facilities, good food hygiene practice Theatres- positive/ negative pressure rooms Immune suppressed patients

Answer 127

Patient - general and specific patient risk factors; interactions with other patients, healthcare workers and visitors Pathogen - virulence factors; ecological interactions- other bacteria and antibiotics/ disinfectants Practice - general and specific activities of healthcare workers, policies and their implementation, organisational structure and engagement, regional and national political initiatives, leadership at all levels from government to the world Place - healthcare environment- fixed and variable features

Answer 128

Gram positive anaerobic, bacillus, spore forming bacteria | Example of a hospital acquired infection

Answer 129

Carriage frequency increases with duration of hospital stay

Answer 130

When gut micro flora are disturbed by antibiotics (cephalosporins and amoxicillin) overgrowth can occur Enterotoxin A and B and binary toxin production causes tissue damage and fluid diarrhoea Some strains which are fluoroquinolone resistance and have evidence of enhanced toxin production are associated with more ever disease and extensive hospital outbreaks

Answer 131

History of previous antibiotic exposure 3/4 loose/ unformed stools per day Possible development of abdominal pain Pseudomembranes seen on sigmoidoscopy on mucosal surface of rectum and sigmoid colon Possible complications of toxic mega colon, bowel perforation and systemic toxicity ---> high mortality

Answer 132

Stop the inciting agent (antibiotic) Treat with metronidazole for 10 days Oral vancomycin and IV metronidazole for severe cases and treatment failures Rapid and strict isolation is essential

Answer 133

Detection of toxin or glutamate dehydrogenase (GDH) by enzyme immunoassay (EIA) Detection of toxin genes by nucleic acid amplification test (NAAT) Typing- generally by ribotyping Full blood count U&Es CRP MC&S

Answer 134

``` Enhanced ward cleaning and attention to hand hygiene is essential Suspect Isolate Gloves and apron Hand hygiene Toxin test ```

Answer 135

Botulinum- botulism Perfringens- gas gangrene, food poisoning Tetanii- tetanus

Answer 136

``` Malaria Typhoid Meningococcal septicaemia Dengue Yellow fever ```

Answer 137

1-3 weeks or longer after bite

Answer 138

Plasmodium falciparum, vivax, ovale and malariae

Answer 139

Female anopheles mosquito

Answer 140

Africa, Asia, Middle East and South and Central America

Answer 141

``` Headache Cough Fatigue Malaise Asthsalgia Myalgia Fever chills and sweats which eventually cycle every 3rd/4th day ```

Answer 142

Other than fever, often few signs (+/- splenomegaly) Cerebral features - coma Respiratory distress (metabolic acidosis, pulmonary oedema)

Answer 143

Should be managed by an ID physician Blood smear to detect parasites FBC, U&Es, LFTs, glucose Head CT if CNS symptoms

Answer 144

Depends on species causing malaria - plasmodium falciparum- (malignant) quinine, artemisinin - p, vivax, ovale, malaria- (benign) chloroquine +/- primaquine for exo erythrocytic phase)

Answer 145

Assess risk - knowledge of at risk areas Bite prevention- repellant, adequate clothing, nets, chemo prophylaxis before travel (must include regular returning travellers) Chemoprophylaxis - specific to region, start before and continue after return -doxycycline

Answer 146

Salmonella enterica serorar Typhi/ Paratyphi A, B or C

Answer 147

Enterobacteriaceae | Aerobic gram negative rods

Answer 148

Gram negative endotoxin VI antigen Invasion which allows IC growth Fimbriae adhere to epithelium over ideal lymphoid tissue (Peyers patches)--> RE system

Answer 149

``` Fever, headache Incubation period- 7-14 days Abdominal discomfort, constipation, dry cough, hepatosplenomegaly, occasionally rash Relative bradycardia Intestinal haemorrhage and perforation Paratyphoid generally milder ```

Answer 150

Moderate anaemia Relative lymphopenia Raised LFTs (transaminase and bilirubin) Culture- faeces, blood Serology (antibody detection)- no longer used

Answer 151

Usually treated with ceftriaxone or azithromycin 7-14 days | Resistance may be present against chloramphenicol, ampicillin. Cotrimoxazole, ciprofloxalin

Answer 152

Food and water hygiene precautions Typhoid vaccine- high risk travel, lab personnel Vicapsular polysaccharide antigen or live attenuated vaccine Modest protective effect (50-75%)

Answer 153

Food poisoning salmonellas- salmonella typhimurium, S.enteritidis Symptoms- diarrhoea, fever, vomiting, abdominal pain Generally self limiting but bacteraemia and deep seated infections may occur- excreting organism in diarrhoea

Answer 154

Primary animal pathogen - brucella abortus (cows) - brucella melitensis (goats and sheep) Gram negative cocobacillus - short rounded rods

Answer 155

South Europe, Africa, Asia, central and South America

Answer 156

Transmission through skin breaks / GI tract (milk)

Answer 157

Non specific febrile illness (undulant fever) Bone, joint involvement Epididymitis - inflammation/ swollen testes

Answer 158

From blood cultures

Answer 159

With doxycycline and rifampicin

Answer 160

Bacteria, viruses, Protozoa Class I MHC (found on all nucleated cells) HLA: A, B, C

Answer 161

Bacteria, parasites, worms, fungi Class II MHC (found on all dendritic cells. Macrophages, B cells) HLA: DR, DQ, DP

Answer 162

Virus (protein) is taken up and presented on cell surfaces

Answer 163

Bacteria taken up and presents in endocytic vesicle which fuses with lysosomes and destroys bacteria

Answer 164

CD8+ T cells - cytotoxic T lymphocytes - process and kill the virus CD4+ T cells (stimulates CD8+ T cells and..) - B cells- antibodies- opsonisation, neutralisaiton, complement activation - macrophages- kill opsonised microbes

Answer 165

CD4+ T cells - eosinophils- killing of parasites - B cells- Antibody: IgG4 (opsonisation), IgA (mucosal protection), IgG&IgE (antibody dependent cell toxicity) and IgE (allergies) - mast cells- local inflammation allergies (IgE) - neutrophils- phagocytosis

Answer 166

``` Gram positive, diplococcus (seen in pairs) Alpha haemolytic (can be variable) ```

Answer 167

Streptococcus pneumoniae has a polysaccharide capsule that protects it's from phagocytosis There are over 90 highly antigenic capsule sero types and antibodies to specific types are protective Pathogenicity- - pro inflamm cell wall components (e.g. c-polysaccharide) F-antigen - IgA2 protease - pneumolysin, a cytotoxin that stimulates immune responses - adhesins that bind to cell surface carbohydrates (e.g. Choline binding protein A, pneumococcal surface protein A) - tissue damaging enzymes

Answer 168

- these occur outside the major organs or the blood and tend to be less serious - bronchitis- infection of bronchi - Otis media - ear infections - sinusitis - infection of sinuses

Answer 169

These occur inside the major organs or the blood and tend to be more serious than non invasive ones - Bacteraemia - Septicaemia - Osteomyelitis - Septic arthritis - Pneumonia - Meningitis

Answer 170

``` Distinctive crackles on chest Blood test Radiography- x ray fluid on lungs Ct scan, MRI scan Blood pressure (low) Lumbar puncture test - sample of CSF Urinary antigen test- urine sample, immunochromatographic assay ```

Answer 171

Non invasive infection - treating bronchitis, middle ear infection, sinusitis Invasive infection - confusion, resp rate >30, low BP, 65 years old ***

Answer 172

Conjugate vaccine incorporating 13 capsular stereotypes | Highly immunogenicity in small children

Answer 173

``` Enterotoxigenic escherichia coli Enteroinvasive escherichia coli Campylobacter Salmonella typhi Shigella Vibrio cholera Giardia lamblia Entamoeba histolytica Cryptosporidium parvum Rotavirus Norovirus ```

Answer 174

Profuse and watery

Answer 175

Mild with abdominal cramp

Answer 176

Profuse and secretory

Answer 177

Watery mild-severe

Answer 178

``` Enveloped orthomyoxovirus (100nm) Contains a negative single stranded RNA genome divided into 8 segments Structure allows genetic reassortment- so that virus can change its surface antigens ```

Answer 179

Avian and pig

Answer 180

7 proteins - 3 of which are responsible for RNA transcription Nucleoprotein has 3 antigenic types that designate 3 main virus groups- A , B and c Matrix protein forms a shell under the lipid envelope with haemagglutin and neuraminidase proteins - expressed as 10 nm spikes on the envelope which interact with host cells - virus immunity directed against H and N

Answer 181

Incubation period- 1 to 4 days Patients infectious for 3 days - starting from one day before symptoms emerge Headache, myalgia, fever, cough lasts for 3 - 4 days Complications which are more common in elderly people and patients with cardiopulmonary disease, include primary viral and secondary bacterial pneumonia

Answer 182

Immunofluorescence inf A, B and C Nucleic acid amplification test (NAAT) - more sensitive and can identify specific stereotype which can indicate whether a patient is infected with a pandemic strain

Answer 183

Amantadine | Neuraminidase inhibitors- zanamivir, oseltamivir (tamiflu), vaccination

Answer 184

Found in rivers, lakes, warm springs, domestic water supplies, fountains, air conditioning systems, swimming pools and jacuzzis

Answer 185

Multiplication occurs at temps between 20 and 40 degree Celsius inside acanthamoeba

Answer 186

Transmission via aerosols generated from showers, and air conditioning systems

Answer 187

Infection associated with previous lung disease, smoking, high alcohol intake, but previously healthy patients can be infected. Immunocompromised patients in hospitals are vulnerable to infection if the hospital air conditioning is not adequately maintained

Answer 188

Major outer membrane protein that inhibits acidification of phagolysosomes Macrophage infectivity is required for optimal internalisation Legionella pneumophilia expresses a potent exoprotease

Answer 189

Mild influenza like illness (pontiac) Severe pneumonia (legionnaires disease) which can lead to respiratory failure and high mortality Patients may complain of nausea, vomiting, malaise before lung symptoms become prominent Cough which is unproductive and dyspnoea which is progressive Confusion is common Inappropriate natiuretic hormone production associated with low serum sodium

Answer 190

Culture of sputum, bronchoalveolar, lavage fluid Rapid diagnosis by antigen detection in urine Direct Immunofluorescence or nucleic acid amplification test (NAAT) of respiratory specimens Serum antibodies can provide retrospective diagnosis for epidemiological purposes

Answer 191

Effective regimens usually consist of a macrolide antibiotic together with rifampicin Legionellosis- prevented by adequate maintenance of air con systems and by ensuring that hot water supplies are above 45 degrees Celsius to prevent multiplication

Answer 192

Gram negative diplococcus bacteria

Answer 193

Number of sero groups (ABC, W-135) based on polysaccharide capsular antigen (acts as endotoxin) - promotes adherence, prevents phagocytosis, and triggers inflammation by cytokines Evades immune system by preventing phagocytosis Outer membrane acts as an endotoxin

Answer 194

Endotoxin binds to macrophages Local- Cytokines (tissue necrosis factors and interleukins TNF alpha and IL1) stimulate inflammatory response to promote wound repair and recruit RE system Systemic- Cytokines released into circulation stimulate oath factor macrophages and platelets, goal is for homeostasis to be restored SIRS- homeostasis not restored Also - cytokines promote coagulation and inhibit fibrinolysis causing microvascular thrombosis and organ ischaemia and failure

Answer 195

Systemic inflammatory response syndrome | Response to non specific insult (trauma, Ischaemia and infection)

Answer 196

Presence of bacteria in blood with or without clinical features

Answer 197

Generalised clinical term related to generalised sepsis

Answer 198

Systemic response to infection- SIRS + documented/ presumed infection

Answer 199

SIRS + organ dysfunction / hypoperfusion --> hypotension/ decreased urine output

Answer 200

Severe sepsis + persistently low BP despite administration of IV fluids

Answer 201

``` 2 or more of : Temp- 38 degrees Celsius H/R > 90/min R/R >20/ min WBC 12x10^9/L. ```

Answer 202

Abdominal pain, fever, nausea, weakness, muscle aches, eye pain on exposure to light, pale, cool extremities, widespread purpuric rash

Answer 203

``` FBC U&Es EDTA bottle for PCR Blood sugar Liver function test C Reactive Protein Clotting studies Blood gases ```

Answer 204

Blood culture PCR of blood Lumbar puncture- culture of CSF (only after checking contraindications- glucose and protein elimination in biochem M&C) PCR of CSF (appearance- turbidity and colour, microscopy - WBCs and RBCs, gram stain- PCR referral)

Answer 205

Sepsis 6 within 1 hour 1) give high flow O2 2) take blood cultures and other cultures 3) administer empirical antibiotics (IV) 4) measure serum lactate 5) start IV fluid resuscitation 6) commence accurate urine output measurement Antibiotics : ceftriaxone

Answer 206

Vaccination- meningococcal vaccines conjugate, achy vaccine- immunocompromised patients and travel protection, serogroup B vaccine, Antibiotic prophylaxis- close contact to infected individuals

Answer 207

``` Irreversible hypotension Respiratory failure Acute kidney injury (renal failure) Raised IC pressure Ischaemic necrosis of digits, hands and feet ```

Answer 208

Gram negative, anaerobic, rod shaped bacterium Commonly found in lower intestine of warm blooded organisms (commensal) Strains vary in fimbriae - giving the consequential disease and mechanism of infection differences

Answer 209

Enterotoxigenic E. coli - produce LT and ST toxins that act on the enteric yet to stimulate fluid secretion- diarrhoea Enteroaggregative E. coli - secrete plasma encoded toxin, a serine protease that binds alpha ford in and causes disruption of actin cytoskeleton - strains express ST toxins and haemolysin like toxins - chronic diarrhoea Enteropathogenic E. coli- colonise epithelial cell lining of small intestin and inject effector proteins that causes efface net of microvilli and intimate adherence Enterohaemorrhagic E. coli- strains produce a veto toxin (in vitro) - Haemorrhagic diarrhoea, complicated by haemolysis and acute renal failure (commensal in cattle - transmitted via hygiene failure) E. coli in ureter- express mannose binding fimbriae - associated with lower UTIs and cystitis

Answer 210

Eatubg/ drinking food contaminated with faeces Meat (infected during processing) - if not heated above 71 degrees celsius Milk and dairy products and raw fruit and veg (which could have come in contact with faeces)

Answer 211

Bloody diarrhoea, stomach cramps, nausea and vomiting, dehydration, some are Asymptomatic, blood, kidney problems Fever, weakness, bruising, passing only small amounts of urine

Answer 212

Stool sample, M,C&S, microbiological investigation (blood, and or mucus in stool or immunocompromised patient) FBC Renal function Urea and electrolytes

Answer 213

Most cases- home care and plenty of fluids IV fluids if hospitalised Antibiotics

Answer 214

Washing hands Washing fruit and veg properly Avoiding cross contamination Using a meat thermometer and cooking meat at proper temp

Answer 215

Single stranded, positive, icosahedral, non enveloped, RNACalcivirus- can cause outbreaks of acute diarrhoea and vomiting in hospitals, care homes, cruise ships and other confined communities Divided into 5 genogroups

Answer 216

Faecal oral route | Aerosols

Answer 217

Symptoms develop after a short incubation period of 24-48 hours

Answer 218

Virus replication occurs in the mucosal epithelium of the small intestine which results in broadening and flattening of villi and hyperplasia of crypt cells

Answer 219

Self limiting acute diarrhoeal illness | Can be present with sudden onset projective vomiting and explosive diarrhoea

Answer 220

NAAT | Sequencing is required for epidemiological purposes and to monitor design of future NAAT detection assays

Answer 221

Isolation Ward closure Good hand washing techniques

Answer 222

Gram positive clusters of cocci

Answer 223

A symptomatic carriage found on 40% of healthy people In nose, skin, axilla or perineum- important in. Healthcare workers especially if they carry an invasive or resistant strain (MRSA)

Answer 224

``` Coagulase Adhesion molecules Lytic enzymes Protein toxins Biofilm formation ```

Answer 225

Coagulase converts fibrinogen to fibrin and may be involved in forming a protective Barrier

Answer 226

Adhesion molecules bing fibronectin and assist with adherence

Answer 227

Lytic enzymes such as lipase breakdown the host tissue

Answer 228

Protein toxins such as panton valentine leucocidin (pvl), the toxic shock syndrome toxin (tsst), enterotoxins cause shock and toxicity

Answer 229

Biofilm formation causes slower growth in extracellular matrix and is difficult to treat with antibiotics- adheres to plastics

Answer 230

Primary skin infections- impetigo- person to person Secondary skin infections- associated with eczema, surgical wounds, intravenous devices, burns Pneumonia- rare but may follow influenza and progress rapidly with cavity formation Endocarditis- rapid and destructive, associated with intravenous drug misuse or colonisation of IV devices Osteomyelitis Septic arthritis

Answer 231

It was initially susceptible to penicillin but strains that produce B lactamases soon predominated so methicillin and related (flucoxacillin) agents were introduced and replaced penicillin Methicillin resistant S.Aureas (MRSA) emerged- resistance caused by presence of mecA gene - codes for a penicillin binding protein that binds the drug less well. Glycopeptides such as vancomycin or teicoplanin started to be required for these strains Intermediate or hetero resistance to Glycopeptides emerged as an increasing issue and fully Glycopeptide resistant strains (GRSA) have now emerged, resistance being mediated from vanA and vanB genes acquired from enterococci

Answer 232

Penicillin if susceptible Flucoxacillin if penicillin resistant Vancomycin or teicoplanin if MR Contril measures are needed in hospitals

Answer 233

Isolation of MRSA and GRSA | Topical mupirocin and chlorhexidune to eradicate carriage

Answer 234

Spreads by airborne transmission and hands of healthcare workers

Answer 235

Blood, U&Es Grows readily on most lab media- selective medium contents high salt to which staph aureus is relatively tolerant Phenotypic identification depends on demonstrating coagulase, catalase enzymes and typical cluster of grapes morphology on gram stain Typing by molecular means can support interventions to control outbreaks

Answer 236

Lentivirus

Answer 237

``` Spherical Enveloped Diploid ss +RNA virus 80-100nm in diameter Non segmented Linear ```

Answer 238

Retrovirus- uses reverse transcriptase to produce a DNA copy from viral RNA that is incorporated into the host nucleus to become the template for further viral RNA 3 genes are required for viral replication- gag, pol and env 2 types of HIV that are pathogenic to humans- HIV1 (most common around world) and HIV2 (largely confined to W Africa, appears less virulent)

Answer 239

Sexually By blood and body fluids From mother to child

Answer 240

Viral RNA is transcribed to ssDNA and integrates into host genome Antigenic variation is rapid Virus principally infects cells with a CD4+ receptors- (T Cells and macrophages) Viral replication results in progressive T cell depletion and diminished cell mediated immunity Lacking T cells means that B cell function is also reduced Damage to neural cells stimulates cytokines release - neurological damage Clinical signs mostly caused by secondary infections which occur because CD4+ is decreased and cell mediated immunity is non functional

Answer 241

50-70% of patients have an acute syndrome occurring 2-6weeks after acquisition of HIV --> rash, fever and lymphadenopathy Only about 25% of these patients have symptoms severe enough to have to seek medical attention CD4+ count declines and if untreated reaches a point ( AIDS Non specific symptoms- fever, malaise, arthralgias, headache, sore throat, with lymphadenopathy Early invasion of nervous system - meningitis, encephalitis, peripheral neuropathy, myclopathy

Answer 242

Bacteria- MTB, mycobacterium intracellulare, Salmonella, streptococcus pneumoniae Protozoa- toxoplasma Gondi, cryptosporidium parvum Fungi- candida sp, cryptococcus neoformans Virus- varicella zoster

Answer 243

Virus can be cultured from circulating mononuclear cells Genome detected by PCR and p24 antigen detected prior to seroconversion (where body makes and antibody to a virus) ELISA is used for antibody screening tests Confirmation either by western blot or line immunoassay

Answer 244

Several classes of antiretrovirals HAART- night a ruche anti retroviral therapy -Nucleoside reverse transcriptase inhibitors (NRTI's) -Non NRTI's -Protease inhibitors -Fusion inhibitors -Integrase inhibitors -Co receptor/ entry inhibitors -Zinc finger inhibitors (Prevent transmission, maintain virus at less than 50 copies, prevent emergence of resistance, restore immunological function)

Answer 245

Avoidance of partners who have a high risk factor and unprotected intercourse Screening of blood products Health education and free needle exchange programme for IV drug users Antigenic diversity has frustrated vaccine development Antiretroviral prophylaxis for infected needle stick injury Mother to child- c section

Answer 246

Hepednavirus Enveloped Contains partially double stranded DNA encoding surface antigen (HBcAg) pre core protein (HBeAg) a large active polymerase protein and a transactivator protein

Answer 247

Replicates through reverse transcriptase

Answer 248

Parenteral, congenital/ vertical and sexual routes

Answer 249

Congenital infection carries high risk of 10% patients develop chronic hepatitis complicated by cirrhosis or hcc Fulminant diseases carries a 1-2% mortality Acute hepatitis of variable severity developes insidiously Fever malaise jaundice Liver failure, liver cirrhosis, hcc

Answer 250

Immunoassay so for HBsAg HBeAg and HBcAg (and associated antibodies) enable diagnosis of acute infection and previous exposure Viral load measured by NAAT and sequencing for resistance mutations allows monitoring for therapy and directs drug choice

Answer 251

Pegylated alpha interferon Lamitudine, adefovir, entecavir, tenofovir, telbinudine and clerudine - antiviral efficacy Emtricitabine and valtorcitabine are nearing clinical introduction Therapy should be considered in chronic infection as responders have reduced risk of liver damage and liver cancer in the long term HBeAg seroconversion often seen as a success of treatment

Answer 252

Those at high risk should be immunised with recombinant HBV vaccine- HBsAg based, 3 doses at 0,1,6 months or 0,12,12 months, 95% effective Vaccine and specific immunoglobulin should be administered to neonates of infected mother to reduce transmission Post exposure prophylaxis- (HBsAg) positive source, newborns from HBsAg positive mothers, needle stick injury for HCW's without protection Blood donations must be effectively screened Needle exchange programmes for drug misusers and sexual health education schemes can help to reduce transmission

Answer 253

Skin- epithelia, hair, nails | Mucosal surfaces- conjunctival, gastrointestinal, respiratory, genitourinary

Answer 254

Papilloma | Herpes simplex

Answer 255

G+ve staphylococcus aureus, coagulative negative staphylococci, corynebacterium G -ve enterobacteriaceae

Answer 256

Yeasts | Dermatophytes

Answer 257

Lactobacilli | Yeasts

Answer 258

Enterobacteriaceae Lactobacilli Streptococci Enterococci

Answer 259

Eubacterium Lactobacillus Coliform Clostridium

Answer 260

Helicobacter Streptococci Staphylococci

Answer 261

Viridans streptococci

Answer 262

Neisseria meningitidis Streptococci pneumoniae Haemophilius influenzae

Answer 263

Staphylococcus aureus

Answer 264

Coagulase negative staphylococci Saprophytic neisseria Viridans group streptococci

Answer 265

Microbiota- commensals; microorganisms carried on skin and mucosal surfaces; normally harmless or even beneficial, transfer to other sites can be harmful Invasion- e.g. Streptococcus pyogenes pharyngitis Migration- e.g. E. coli urinary tract Innoculation- e.g. Coagulase negative staphylococcus prosthetic joint infection Haematogenous- e.g. Viridans streptococcus endocarditis

Answer 266

``` Cellulitis Pharyngitis Conjunctivitis Gastroenteritis UTI Pneumonia ```

Answer 267

Endovascular- endocarditis, vasculitis Septic arthritis Osteomyelitis Empyema

Answer 268

``` Intravascular lines Peritoneal dialysis catheters Prosthetic joints Cardiac valves Pacing wires Endovascular grafts Ventriculooeritoneal shunts ```

Answer 269

Coagulase negative staphylococci

Answer 270

``` Viridans streptococci Enterococcus faecalis Staphylococcus aureus HACEK group Candida ```

Answer 271

Coagulase negative staphylococci | Staphylococcus aureus

Answer 272

Adherence to host cell or prosthetic surfaces (pili, fimbriae) Biofilm formation Invasion and multiplication Host response- pyogenic (neutrophils --> pus) or granulomatous (fibroblasts, lymphocytes, macrophages --> nodular inflammatory lesions)

Answer 273

Starvation can induce bacteria to shrink and adopt a spore like state known as ultra-micro bacteria which wait in water soil rock or tissue until conditions are suitable for active growth Active bacteria can attach to almost any surface – changes in gene expression transform swimmers to stickers within minutes Attached bacteria multiply and encase colonies with a slimy matrix Nutrients defuse into the matrix Close proximity of cells in the matrix facilitates exchange of molecular signals that regulate behaviour Although antimicrobials damage outer cell layers – biofilm community is Propelled by shear forces aggregated cells can become detached or roll or ripple along the surface in sheets and remain in their protected biofilm state

Answer 274

Controls- sporulation, biofilm formation, virulence factor secretion 3 principles- signalling molecules (auto inducers), cell surface cytoplasmic receptors, gene expression--> cooperative behaviour and more AI production

Answer 275

Diagnosis- aim is to identify infecting organism and it's antimicrobial susceptibilities (sterilise tissue and reduce bio burden); challenges- adherent organisms and low metabolic state/small colony variants; blood cultures; tissue/prosthetic material senication and culture; antibacterials; remove prosthetic material; surgery (resect infected material) Challenges- low metabolic activity of biofilm microorganisms; poor antibacterial penetration into biofilm

Answer 276

Maintain surface integrity Prevent bacterial surface contamination Remove colonising bacteria

Answer 277

Prevent contamination Inhibit surface colonisation Remove colonising bacteria

Answer 278

Antigen specific immune responses that are either inappropriate or excessive and result in harm to host

Answer 279

Sensitisation phase - first encounter with the antigen | Effector phase - clinical pathology upon reexposure to the same antigen

Answer 280

Type I - immediate, allergy, (<30min); environmental non infectious allergens (antigens) Type II - antibody mediated (5-12 hours)- antibodies directed against an antigen on the surface of pathogen Type III - immune complex mediated (3-8 hours)- antibodies directed against soluble antigens on immune complex Type IV - cell mediated (24-48 hours)- T cells and B cells - environmental infectious agents and self antigens

Answer 281

Most forms of hypersensitivity are non-life threatening. Anaphylaxis however is a severe form of Type I hypersensitivity reaction, triggered by the exposure of a pre-sensitised individual to an allergen, causing systemic mast cell degranulation. This leads to: o Vasodilation o Tissue oedema o Airways obstruction o Fall in blood pressure o Shock Acute anaphylaxis should be treated with intramuscular adrenaline, which promptly reverses the symptoms and signs with an increase in blood pressure and reversal of airways obstruction.

Answer 282

Explains why people have allergies

Answer 283

House dust mite, cockroaches Animals especially domestic pets- cats and dogs Tree and grass pollens Insect venom such as that contained in wasp and bee stings Medicines - e.g. Penicillin Chemicals such as latex Foods- peanuts, milk, nuts etc.

Answer 284

Mast cells

Answer 285

``` Enzymes- Toxic mediators- Cytokines Chemokines Lipid mediator ```

Answer 286

tryptase, chymase- remodel connective tissue matrix

Answer 287

histamine, heparin- toxic to parasites, increase vascular permeability cause smooth muscle contraction

Answer 288

IL4, IL13 - stimulate and amplify TH2 cell response IL3-IL5 - promote eosinophil production and activation TNF-alpha - promotes inflammation, stimulation of cytokines production by many cell types activates endothelium

Answer 289

CCL3 (MIP-1alpha) - attracts monocytes, macrophage and neutrophils

Answer 290

Leukotrienes- C4, D4, E4 Cause smooth muscle contraction increase vascular permeability, stimulate mucus secretion Platelet activating factors- attracts leukocytes, amplifies production of lipid mediators , activates neutrophils, eosinophils and platelets

Answer 291

Cross-Linking of Antigen-Specific IgE molecules on surface of mast cells or basophils. The cross-linking leads to the degranulation of the cells and the release of vasoactive substances. Reactions typically occur in minutes and form the basis of most common types of allergies, and represent a component of childhood asthma (HDM etc.).

Answer 292

Type II – Antibody Mediated Hypersensitivity IgG antibodies reacting with antigen present on tissues or on the surface of cells. Once the antibodies have bound with the antigen, they interact with complement or the Fc receptor on phagocytic cells, activating these innate mechanisms leading to the induction of a localised inflammatory response and tissue damage. These reactions may occur very quickly, but may also lead to prolonged activation. Examples include: o Goodpasture’s syndrome • Autoantibodies to basement membrane in the lung and kidney o Haemolytic anaemias / Rhesus disease o Stimulating Ab’s • TSH in Grave’s disease o Blocking Ab’s • Ach R in Myasthenia Gravis • Insulin receptor in diabetes

Answer 293

Type III – Immune Complex Mediated Hypersensitivity Deposition of immune complexes, usually IgG antibodies. The immune complexes are deposited in various tissues, where they set up inflammatory reactions similar to Type II reactions (Complement activation, phagocyte Fc receptor). The commonest sites of Type III reactions are the skin, joints and kidney, and so present with rash, arthritis and/or nephritis. Examples include: o Systemic Lupus Erythematosus o Farmer’s lung

Answer 294

Type IV – Delayed Hypersensitivity T helper cells activate macrophages or cytotoxic T cells. ``` Activated macrophages/cytotoxic T cells cause tissue damage. Typically delayed hypersensitivity reactions occur two to three days after exposure to the antigen. Examples include: o External antigens • Tuberculoid Leprosy • Contact dermatitis o Autoimmune • Coeliac disease • Multiple sclerosis ```

Answer 295

Increased vascular permeability Vasodilatation Bronchial constriction

Answer 296

Blood, serum levels of mast cell products

Answer 297

Inner arm usually Mast cells in epidermis activated Due to increased vascular permeability and vasodilation - wheal and flare reaction- urticaria Needs a trained personell, risk of anaphylaxis in highly sensitive subjects

Answer 298

Mast cells in deep dermis are activated | Angio oedema- lips, eyes, tongue, upper respiratory airways (fatal)

Answer 299

Bloodstream- Anaphylaxis Systemic activation of mast cells Hypoventilation, cardiovascular collapse, generalised urticaria, angio oedema - face and resp tract, wheezing

Answer 300

Epinephrine/ adrenaline (IM)-acts on alpha1, beta 1 and beta 2 receptors Reverses peripheral vasodilation and reduces oedema Reverses airway obstruction/ bronchospasm Increases force of myocardial contraction Inhibits mast cell activation Do not delay treatment- 30 minute window Monitor pulse, BP, EG and oximetry

Answer 301

Clinical history- atopy, allergens, seasonality and route of exposure Blood test- serum allergen specific IgE Serum mast cell tryptase, histamine (systemic degranulation) Skin prick tests- range of allergens - wheal and flare reaction (>3mm), no antihistamines Challenge tests: food and drug allergies - slight risk of anaphylaxis in highly sensitive patients

Answer 302

Allergen avoidance / elimination Education- parents recognise symptoms, EPIPEN use and call emergency services Medic alert identification tags Drugs- antihistamines (alternate sedating/ non sedating), corticosteroids (topic/systemic), anti IgE igG (omalizulab), anaphylaxis- give injectable adrenaline 0.5mg Allergen desensitisation - involves administration of increasing doses of allergen extracts over a period of years given to patient by injection/ drops/ tablet under tongue (sublingual) ; 90% effective in patients with bee and wasp venom anaphylaxis; given to patients with increased risk of systemic attacks; specialist hospital based unit with resuscitation equipment

Answer 303

Heart valves may become infected during transient bacteraemia Congenitally abnormal or damaged valves are at greater risk Bacteria may originate from mouth, urinary tract, intravenous drug misuse or colonised intravascular lines

Answer 304

``` Viridans group streptococci Enterococci Other streptococci Staphylococcus aureus Coagulase negative staphylococci Fastidious gram negatives ```

Answer 305

``` Coagulase negative staphylococci Staphylococcus aureus Viridans group streptococci Enterococci and other streptococci Fungi ```

Answer 306

``` NB. Serological diagnosis Previous antibiotic therapy Chlamydophila pneumoniae/chlamydia psittaci Coxiella brunetti- Q fever Mycoplasma ```

Answer 307

Nutritionally deficient strains Staphylococcus aureus Mixed infections Fungi

Answer 308

Damage and roughening of endothelium --> fibrin and platelet deposition --> colonisation of deposit --> bacterial multiplication, further fibrin and platelet deposition, immune activation --> systemic signs of infection! development of vegetation, toxic, embolic and immune complex phenomena

Answer 309

Malaise, fever, variable heart murmurs, arthralgia Classical stigmata - splinter haemorrhages, oilers nodes, microhaematuria, retinal infarcts, finger clubbing, janeway lesions (only in long standing infection) Later stages- septic emboli may cause a stroke With aggressive organisms staphylococcus aureu, disease progresses rapidly and valves may rupture

Answer 310

Diagnosis is made if there are two major Dulce criteria present, or 1 major and 3 minor Major- blood culture with characteristic organisms; persistently positive blood cultures with any organism; evidence of endocardial involvement demonstrated by echocardiogram; new valvular regurgitation Minor- predisposition, fever (>8C), immunological signs

Answer 311

Local progression may lead to aortic root abscess Valve destruction may lead to cardiac decompensation Cerebral / limb infarction ya follow septic embolus Nephritis secondary to immune complex deposition can progress rapidly if sepsis is uncontrolled or if antibiotics with renal toxicity are given without care

Answer 312

Echocardiography Transthoracic or grand oesophageal demonstrate vegetations in valves Plain chest x ray - evidence of cardiac failure At least 3 sets of blood cultures an hour apart while fever is present Antibiotic therapy should await blood culture - serum tested for antibodies to Coxiella, bartonella, and chlamidya psittaci

Answer 313

Antibiotics - on,y when causative organism is known Based on MIC and MBC of antibiotics If gentamicin is used, concentrations must be monitored closely 2-6 weeks Surgical management

Answer 314

Many (all) infections are transmissible: - From a non human source to a human ( food- E. coli, water- cholera, environment- legionella, animals- rabies) - From person to person directly (influenza, reovirus, neisserria gonorrhoea) or indirectly (mosquitoes- dengue, malaria, cats- cat scratch/ toxoplasmosis, ticks- Lyme disease, spotted fever)

Answer 315

Endemic disease Outbreak Epidemic Pandemic

Answer 316

The usual background rate

Answer 317

Two or more places linked in time and place

Answer 318

A rate of infection greater than the usual background rate

Answer 319

Very high rate of infections spreading across many regions, countries and continents

Answer 320

R0 the average number of cases one case generates over the course of its infectious period in an otherwise uninfected, non immune population If R0 > 1 => increase in cases If R0 = 1 => stable number of cases If R0 < 1 => decrease in cases

Answer 321

Appropriate use of antimicrobials Optimal clinical outcomes Minimise toxicity and other adverse events Reduce the cost of healthcare for infections Limit the selection for antimicrobial resistant strains

Answer 322

Multidisciplinary team and relationships to other quality/ safety teams Surveillance- process measures (measuring what you do) and outcome measures (measuring results you get as a result of what you do) Interventions- persuasive, restrictive, structural

Answer 323

Number of microorganisms required to cause infection | Determines transmissibility

Answer 324

By organism By presentation of microorganism By immunity of potential host

Answer 325

Antibacterials including disinfectants Decontamination Sterilisation

Answer 326

Eliminate vector breeding sites

Answer 327

Nutrition | Medical treatment

Answer 328

Passive- e.g. Maternal antibody, intravenous immunoglobulin | Active- i.e. Vaccination - herd immunity

Answer 329

Herd immunity is a form of immunity that occurs when the vaccination of a significant portion of a population (or herd) provides a measure of protection for individuals who have not developed immunity or been vaccinated

Answer 330

Geographic- don't go there Protective clothing/ equipment- long sleeves, trousers against mosquito bites; personal protective equipment in hospitals (PPE) (gowns, gloves, masks) Behavioural- safe sex, safe disposal of sharps, food and drink prep

Answer 331

Safe water Safe air Good quality housing Well designed healthcare facilities

Answer 332

• Decreased incidence or elimination of disease/organism – Smallpox – Polio – Dracunculiasis

Answer 333

• Decreased exposure to pathogen --> decreased immune stimulus --> decreased antibody --> increased susceptibles --> outbreak • Later average age of exposure --> increased severity – e.g. polio, hepatitis A, chicken pox, congenital rubella syndrome

Answer 334

Chronic diseases cause a change in the structure or function of affected tissues/ organs which may have the potential for changing the interaction between the patient and microorganisms This may be subsequently and further affected by changes caused by the altered presence of microorganisms and the consequences of treatment e.g. with antibiotics and steroids

Answer 335

AR, defect in CF transmembrane conductance regulator gene in exocrine glands Range of different mutations Most frequent

Answer 336

Defect in CFTR- defect in Cl- transmembrane transport Mucus becomes dehydrated and thick causing blockage in small ducts / characteristic salty sweat Long colonisation and infection with a procession of different organisms Lung damage, antibacterial and steroid treatment

Answer 337

H. Influenzae Staph Aureus Pseudomonas Aeruginosa, Burkholderia Cepacia Atypical Mycobacteria, Candida albicans, Aspergillus fumigatus

Answer 338

Heterozygosity provides resistance to cholera, typhoid, TB In vitro interactions between CFTR protein and cholerol toxin, salmonella typhi, IC entry but no in vivo demonstration of benefit

Answer 339

Neutrophils and macrophages

Answer 340

``` S.Pneumoniae H.influenzae Moraxella catarrhalis Ps. Aeruginosa E.Coli ```

Answer 341

``` Respiratory syncytial virus Rhinovirus Parainfluenza virus Human metapneumovirus Coronavirus Adenovirus Influenza A virus ```

Answer 342

Hyperglycaemia and acidaemia impair- humoral immunity, polymorphonucleanuclear leukocytes and lymphocyte functions Diabetic microvascular and macrovascular disease result in poor tissue perfusion and increased risk of infection Diabetic neuropathy- diminished sensation resulting in areas of skin which become unnoticed

Answer 343

Malignant or necrotising otitis externa - pseudomonas aeruginosa - infection starts in external auditory canal and spreads to adjacent soft tissue, cartilage and bone - patients typically present with severe ear pain and otorrhoea Rhino cerebral mucormycosis - in patients with poorly controlled diabetes - especially diabetic ketoacidosis - mould fungi - organisms colonise nose and paranasal sinuses, spreading to adjacent tissues by invading blood vessels and causing soft tissue necrosis and bony erosion

Answer 344

Neurogenic bladder due to diabetic neuropathy leads to defects in bladder emptying Increased risk of a symptomatic bacteriuria and pyuria, cystitis and upper UTIs Enterobacteriaceae (e.g. E.Coli), Ps Aeuroginosa

Answer 345

CNS diseases- Alzheimers, MS, Parkinson's, Encephalitis, Stroke PNS diseases- nerve damage, due to long term heavy alcohol abuse, long term diabetes, neuropathy, syphilis, herniated disk, spinal canal stenosis, pelvic surgery; vitamin B12 deficiency

Answer 346

Skin and soft tissue S.Aureus (folliculitis, cellulitis) Group A B haemolytic streptococcus (cellulitis) Poly microbial- including 2 of above- enterobacteriaceae, various anaerobes - diabetic foot ulcers and necrotising fascitis

Answer 347

Respiratory tract infections (viral and bacterial) More common in young people with DS Due to true immunodeficiency or to other factors- altered mucus secretion/ structure of mouth and airways Otherwise healthy person with DS will probably not suffer more serious infections than siblings and will respond to vaccinations

Answer 348

Decreased neutrophil and monocyte function (chemotaxis, phagocytosis, oxidative burst) Normal number of neutrophils and monocytes Lower (children) or raised (adults) Ig levels despite normal B cell number Normal or high levels of serum IgA and secretory IgA Lowered specific antibody responses upon immunisation Normal/ raised levels of C3/C4/C5

Answer 349

Altered distribution of T cell populations (e.g. Low CD4+:CD8+) but normal T cell number Decreased T cell function including response to specific antigens and some mitogens Altered T cell intracellular signalling Abnormal cytokines production Lowering of some/ not all NK functions - increased number of NK cells

Answer 350

``` Endocarditis Pneumonia Bacteraemia Meningitis ENT- external otitis Eye infections UTIs GI tract infection Skin and soft tissue infection ```

Answer 351

State in which the immune system is unable to respond appropriately and effectively to infectious microorganisms Qualitative and quantitative defect of one or more components of the immune system

Answer 352

``` Infections suggesting underlying immune deficiency are defined as SPUR and so will be: Severe Persistent Unusual Recurrent ```

Answer 353

An increase in frequency and severity of infections | Autoimmune deficiencies and malignancy

Answer 354

Single gene disorder (or polygenic) which affects the immune system directly HLA polymorphisms

Answer 355

Underlying disease or condition affecting immune components | Causing decreased components produced and increased loss and catabolism of immune components

Answer 356

CVID- inability of B cells to mature into plasma cells IgA deficiency- B cell unable to switch to IgA Bruton's disease- impaired B cell development Hyper IgM syndrome- CD40 ligand on activated T cells

Answer 357

Reduced production of IgA --> recurrent upper and lower respiratory tract infections (bronchiectasis); GI complications including infections (Giardia) Arthropathies (including mycoplasma and urea plasma) Increased incidence of AI disease and lymphoma & gastric carcinoma Low IgM and IgG because vaccines don't amount in antibody production

Answer 358

Prophylactic antibiotics Immunoglobulin replacement therapy ( serum IgG > 8) Management of other infections and respiratory function Avoid unnecessary exposure to radiation

Answer 359

Di George syndrome- defect in embryogenesis and incomplete development of thymus gland STEM CELL DEFECT- Severe combined immunodeficiency (SCID - decreased B and T cells)- defect in gamma chain used by many receptors- IL2,4,7,9 DEATH OF DEVELOPING THYMOCYTES - Severe combined immunodeficiency (SCID) - defect in adenosine deaminase (ADA) purine nucleoside phosphorylase (PNP) DEFECTIVE T CELL DEVELOPMENT- Severe combined immunodeficiency (SCID) and Omenns syndrome- defect in genes critical for TCR rearrangement and maturation

Answer 360

``` Cardiac abnormalities Abnormal facies Thymic hypoplasia Cleft palate Hypocalcaemia 22- chromosomal abnormality ```

Answer 361

Neonatal cardiac surgery Supplement to correct hypocalcaemia Immune defect variable (low T cell number) - if lower than 0.4x10^9/L- PCP prophylaxis with antibiotics - bone marrow transplantation (severe forms) Use only X irradiated and CMV (-) blood No live vaccines (BCG, MMR, oral polio)

Answer 362

``` Failure to thrive Long term Antibiotic therapy Deep skin and abscesses of organs Low lymphocyte count (<4-10 cells /ul) Hugh susceptibility to fungal and viral infections - PCP, VZV, CMV, EBV ```

Answer 363

Short term- no live vaccines, only irradiated, CMV- blood products; aggressive treatment of infections, prevention of new infections Long term- bone marrow/ stem cell transplant, gene therapy

Answer 364

Periodicity- Cyclic neutropenia Leukocyte adhesion deficiency (LAD)- adhesion to endothelium affected, lack of CD18 protein on phagocytes Chronic granulomatous disease- intracellular killing affected, lack of respiratory burst- NADPH oxidase deficiency Chediak Higashi syndrome- failure of phagolysosome formation

Answer 365

Prolonged and recurrent infections - skin and mucous membranes - osteomyelitis - deep abscesses (staph A) - commonly staphylococcal (cat +ve) - invasive aspergillosis - inflammatory problems- (GRANULOMA)

Answer 366

``` Prophylactic antibiotics/ Antifungal agent/ immunisation Surgical management Interferon gamma - CGD Steroids- CHD Stem cell transplantation ```

Answer 367

Hereditary angio oedema C1 inhibitor deficiency C1 inhibitor usually inhibits C1 and bradykinin preventing the complement cascade But in deficiency in HAO there is little/no control over the complement cascaded So you get vasodilation and increased vascular permeability as well as increased phagocytosis etc.

Answer 368

C1 inhibitor infusion | Fresh frozen plasma

Answer 369

``` Malnutrition Infection (HIV) Liver diseases Lymphoproliferative diseases Drug induced neutropenia Splenectomy ```

Answer 370

Drugs- e,g, phenytoin, chloramphenicol, alcohol (abuse) Autoimmune Infections- hep B/C, HIV, CMV, Typhoid Bone marrow infiltration with malignancy Aplastic anaemia Vitamin B12/ Folate/ Iron deficiency Chemotherapy- cytotoxic and immunosuppressants Exposure to chemical agents- benzene, organophosphate Radiotherapy

Answer 371

Neutrophils (< 1 x 10 ^ 9) Treat suspected neutropenic sepsis as an acute medical emergency and offer empiric antibiotic therapy immediately Assess patients risk of septic complications

Answer 372

``` Infarction (sickle cell anaemia) Trauma Autoimmune haemolytic disease Infiltration (tumour) Coeliac disease Congenital ```

Answer 373

Increased susceptibility to encapsulated bacteria- haemophiliis influenzae, streptococcus pneumoniae, neisseria meningitidis OPSI- (overwhelming post splenectomy infection) - sepsis and meningitis

Answer 374

Penicillin prophylaxis (life long) Immunisation against encapsulated bacteria (at least 2 weeks before splenectomy if possible) Patient info- medic alert bracelet

Answer 375

Immune - blood borne pathogens- encapsulated bacteria - antibody production- acute response: IgM production; long term production: IgG production - splenic macrophages - removal of opsonised microbes, removal of immune complexes

Answer 376

haemophiliis influenzae, streptococcus pneumoniae, neisseria meningitidis

Answer 377

Protein losing conditions - nephropathy and enteropathy Burns

Answer 378

Staph aureus and strep pyogenes | Neutrophils

Infection Flashcards

(418 cards)