Infectious diseases Flashcards

1
Q

what is the difference between gram positive and negative bacteria?

A

Gram positive bacteria have a thick peptidoglycan cell wall that stains with crystal violet stain. Gram negative bacteria don’t have this thick peptidoglycan cell wall and don’t stain with crystal violet stain but will stain with other stains.

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2
Q

infection table

A

look a

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3
Q

what is the abx tx for MRSA?

A

doxycycline or vancomycin

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4
Q

how is this infection treated?

A

“treat with antibiotics as per the local antibiotic policy”

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5
Q

how do you take an allergy hx?

A

When taking an allergy history always ask what reaction patients have had to become labelled allergic. If they report diarrhoea for example, this is a side effect rather than an allergy and means if necessary (for example in life threatening sepsis) they can still receive that medication

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6
Q

which abx can be used to treat gram psoitive bacteria?

A

amoxicillin, co-amox, clarithromycin, clindamycin, doxycycline, vancomycin

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7
Q

which abx can be used to treat gram neg bacteria?

A

co-amox, genatmicin, ciprofloxacin, doxycylcline

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8
Q

which abx can be used to treat anaerobic bacteria?

A

co-amox, clindamycin, metrondiazole, doxycyline

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9
Q

which abx can be used to treat atypical bacteria?

A

clarithromycin, ciprofloxacin, doxycyline

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10
Q

what is the stepwise process of escalating antibiotic treatment?

A

Start with amoxicillin which covers streptococcus, listeria and enterococcus
Switch to co-amoxiclav to additionally cover staphylococcus, haemophilus and e. coli
Switch to tazocin to additionally cover pseudomonas
Switch to meropenem to additionally cover ESBLs
Add teicoplanin or vancomycin to cover MRSA
Add clarithromycin or doxycycline to cover atypical bacteria

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11
Q

what is the pathophysiology behind sepsis?

A

bacteria recognised by macrophages/lymphocytes - cytokines acctive other parts of immune system
- vasodilation from NO
- endothelium line more permeable - oedema
- activates coag system - thrombocytopenia, haemorrahges, DIC
- blood lactate rises due to hypoperfusion

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12
Q

define septic shock

A

hen arterial blood pressure drops and results in organ hypo-perfusion. This leads to a rise in blood lactate as the organs begin anaerobic respiration

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13
Q

how is septic shock measured?

A

Systolic blood pressure less than 90 despite fluid resuscitation
Hyperlactaemia (lactate > 4 mmol/L)

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14
Q

how is septic shock managed?

A

ICU
Iv bolus
Noradrenaline

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15
Q

define severe sepsis

A

when sepsis results in organ dysfunction
Hypoxia
Oliguria
Acute Kidney Injury
Thrombocytopenia
Coagulation dysfunction
Hypotension
Hyperlactaemia (> 2 mmol/L)

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16
Q

what are the risk factors for developing sepsis?

A

Very young or old patients (under 1 or over 75 years)
Chronic conditions such as COPD and diabetes
Chemotherapy, immunosuppressants or steroids
Surgery or recent trauma or burns
Pregnancy or peripartum
Indwelling medical devices such as catheters or central lines

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17
Q

what is the NEWS score?

A

early signs of sepsis
Temperature
Heart rate
Respiratory rate
Oxygen saturations
Blood pressure
Consciousness level
Other signs on examination:

Signs of potential sources such as cellulitis, discharge from a wound, cough or dysuria
Non-blanching rash can indicate meningococcal septicaemia
Reduced urine output
Mottled skin
Cyanosis
Arrhythmias such as new onset atrial fibrillation

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18
Q

what is often the first sign of sepsis?

A

tachypnoea

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19
Q

how do elderley people atypically present with sepsis?

A

confusion/drowsy

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20
Q

which pts may appear normal on observations but are acutely unwell?

A

neutropenia and immunosuppressed

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21
Q

which investigations are required for suspected sepsis?

A

Full blood count to assess cell count including white cells and neutrophils
U&Es to assess kidney function and for acute kidney injury
LFTs to assess liver function and for possible source of infection
CRP to assess inflammation
Clotting to assess for disseminated intravascular coagulopathy (DIC)
Blood cultures to assess for bacteraemia
Blood gas to assess lactate, pH and glucose
Additional investigations can be helpful in locating the source of the infection:

Urine dipstick and culture
Chest xray
CT scan if intra-abdominal infection or abscess is suspected
Lumbar puncture for meningitis or encephalitis

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22
Q

how are sepsis patients managed?

A

Patients should be assessed and treatment initiated within 1 hour of presenting with suspected sepsis
sepsis 6
Three Tests:

Blood lactate level
Blood cultures
Urine output
Three Treatments:

Oxygen to maintain oxygen saturations 94-98% (or 88-92% in COPD)
Empirical broad spectrum antibiotics
IV fluids

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23
Q

define neutropenic sepsis and some causes

A

sepsis in a patient with a low neutrophil count of less than 1 x 109/L.
Anti-cancer chemotherapy
Clozapine (schizophrenia)
Hydroxychloroquine (rheumatoid arthritis)
Methotrexate (rheumatoid arthritis)
Sulfasalazine (rheumatoid arthritis)
Carbimazole (hyperthyroidism)
Quinine (malaria)
Infliximab (monoclonal antibody use for immunosuppression)
Rituximab (monoclonal antibody use for immunosuppression)

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24
Q

how is neutropenic sepsis treated?

A

sepsis 6 - may gave different policy
with immediate broad spectrum antibiotics such as piperacillin with tazobactam (tazocin)

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25
Q

what are the two main causes of a chest infection?

A

Streptococcus pneumoniae (50%)
Haemophilus influenzae (20%)

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26
Q

what are the other causes and their associations of a chest infection?

A

Moraxella catarrhalis in immunocompromised patients or those with chronic pulmonary disease
Pseudomonas aeruginosa in patients with cystic fibrosis or bronchiectasis
Staphylococcus aureus in patients with cystic fibrosis

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27
Q

what are the 5 causes of atypical pneumonia?

A

“legions of psittaci MCQs”:
Legions – Legionella pneumophila
Psittaci – Chlamydia psittaci
M – Mycoplasma pneumoniae
C – Chlamydydophila pneumoniae
Qs – Q fever (coxiella burnetii)

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28
Q

what is the abx used in chest infection?

A

Amoxicillin
Alternatives:

Erythromycin / clarithromycin
Doxycycline

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29
Q

which abx are used to treat atypical chest infections?

A

clarithromycin
levofloxacin
doxycycline

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30
Q

what are the sx of UTI?

A

Dysuria (pain, stinging or burning when passing urine)
Suprapubic pain or discomfort
Frequency
Urgency
Incontinence
Confusion is commonly the only symptom in older more frail patients

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31
Q

what are the sx of pyelonephritis?

A

Fever is a more prominent feature than lower urinary tract infections.
Loin, suprapubic or back pain. This may be bilateral or unilateral.
Looking and feeling generally unwell
Vomiting
Loss of appetite
Haematuria
Renal angle tenderness on examination

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32
Q

how is a UTI investigated?

A

urine dipstick
MSU to microbiology lab for culture and sensitivity trsting

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33
Q

how are the results of urine dipstick interpreted?

A

Nitrites are a better indication of infection than leukocytes. If both are present then the patient should be treated as a UTI. If only nitrites are present then it is worth treating as a UTI however if only leukocytes are present then the patient should not be treated as a UTI unless there is clinical evidence that they have a UTI

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34
Q

what is the likely causative organism of UTI and some other causes?

A

E.coli
Klebsiella pneumoniae (gram-negative anaerobic rod)
Enterococcus
Pseudomonas aeruginosa
Staphylococcus saprophyticus
Candida albicans (fungal)

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35
Q

how is UTI managed?

A

3 days of antibiotics for a simple lower urinary tract infection in women
5-10 days of antibiotics for women that are immunosuppressed, have abnormal anatomy or impaired kidney function
7 days of antibiotics for men, pregnant women or catheter related UTIs
- Trimethoprim
- Nitrofurantoin

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36
Q

how are UTI’s managed in pregnancy?

A

increase the risk of pyelonephritis, premature rupture of membranes and pre-term labour.
7 days of antibiotics (even with asymptomatic bacteruria)
Urine for culture and sensitivities
First line: nitrofurantoin
Second line: cefalexin or amoxicillin
Nitrofurantoin is generally avoided in the third trimester as it is linked with haemolytic anaemia in the newborn.
Trimethoprim is generally considered safe in pregnancy but avoided in the first trimester or if they are on another medication that affects folic acid (such as anti-epileptics) due to the anti-folate effects.

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37
Q

how is pyelonephritis managed?

A

hospital if septic
7-10 days -
Cefalexin
Co-amoxiclav
Trimethoprim
Ciprofloxacin

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38
Q

define cellulitis

A

infection of the skin and the soft tissues underneath
from breach in skin barrier - trauma,eczema, fungal nail, ulcers

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39
Q

what skin changes will be seen in cellulitis?

A

Erythema (red discolouration)
Warm or hot to touch
Tense
Thickened
Oedematous
Bullae (fluid-filled blisters)
A golden-yellow crust can be present and indicate a staphylococcus aureus infection

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40
Q

what are the most common cause of cellulitis?

A

Staphylococcus aureus
Group A Streptococcus (mainly streptococcus pyogenes)
Group C Streptococcus (mainly Streptococcus dysgalactiae)
MRSA

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41
Q

how is the severity of cellulitis classified?

A

Eron:
Class 1 – no systemic toxicity or comorbidity
Class 2 – systemic toxicity or comorbidity
Class 3 – significant systemic toxicity or significant comorbidity
Class 4 – sepsis or life-threatening

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42
Q

how is cellulitis treated?

A

flucloxacillin
or clarithroycin, clindamycin, co-amoxiclav

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43
Q

in which circumstances can antibiotics be used for viral infections?

A

immunocompromised, several co morbidities

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44
Q

is tonsilitis, otitis media and rhinosinusitis more viral or bacterial

A

viral

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45
Q

what is bacterial tonsillitis most commonly caused by?

A

Group A Streptococcus (GAS) infections, mainly streptococcus pyogenes.

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46
Q

what are otitis media, tonsillitis and sinusitis most commonly caused by?

A

Streptococcus pneumoniae - most
Haemophilus influenzae
Morazella catarrhalis
Staphylococcus aureus

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47
Q

how is tonsilitis established to be a viral or bacterial infection?

A

centor criteria:
< 3 indicates they are unlikely to benefit from an antibiotic and antibiotics should not routinely be given. A score of ≥ 3 gives a 40 – 60 % probability of bacterial tonsillitis and it is appropriate to offer antibiotics. One point is given for each of the following:

Fever > 38ºC
Tonsillar exudates
Absence of cough
Tender anterior cervical lymph nodes (lymphadenopathy)

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48
Q

how is bacterial tonsilitis treated?

A

penicillin V for 10 days

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49
Q

how does otitis media present

A

ear pain
bulging red tympanic membrane
ear drum perforates - discharge

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50
Q

how is otitis media treated if it is bacterial?

A

amoxicillin

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51
Q

what are the NICE guidlines for managing sinusitis?

A

Symptoms for less than 10 days: No antibiotics.
No improvement after 10 days: 2 weeks of high-dose steroid nasal spray
No improvement after 10 days and likely bacterial cause: consider delayed or immediate prescription of antibiotics
Penicillin V (also called phenoxymethylpenicillin) for a 5 day course is typically first line

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52
Q

what are the possible intra-abdominal infections?

A

Acute diverticulitis
Cholecystitis (with secondary infection)
Ascending cholangitis
Appendicitis
Spontaneous bacterial peritonitis
Intra-abdominal abscess

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53
Q

what are the common causes of intra-abdominal infections?

A

Anaerobes (e.g. bacteroides and clostridium)
E. coli
Klebsiella
Enterococcus
Streptococcus

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54
Q

what are the commonc regimes for inta abdominal infections?

A

Co-amoxiclav alone
Amoxicillin plus gentamicin plus metronidazole
Ciprofloxacin plus metronidazole (penicillin allergy)
Vancomycin plus gentamicin plus metronidazole (penicillin allergy)

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55
Q

what is spontaneous bacterial peritonitis caused by?

A

liver failure

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56
Q

what is the first line treatment for spontaneous bacterial peritonitis?

A

piperacillin/tazobactam (tazocin)

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57
Q

how does septic arthritis present?

A

Hot, red, swollen and painful joint
Stiffness and reduced range of motion
Systemic symptoms such as fever, lethargy and sepsis

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58
Q

what is the most common causative organism of septic arthritis?

A

staph aureus
or
Neisseria gonorrhoea (gonococcus) in sexually active individuals
Group A Streptococcus (most commonly Streptococcus pyogenes)
Haemophilus influenza
Escherichia coli (E. coli)

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59
Q

what are the ddx for septic arthritis?

A

gout
pseudogout
reactive arthritis
haemoarthritis

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60
Q

how is septic arthritis managed?

A

aspirate = gram stain, micrscopy, culture, sensitivites
give empiral abx IV for 3-6 weeks
Flucloxacillin plus rifampicin is often first line

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61
Q

what is the pathophysiology of influenza?

A

three types: A, B and C, of which A and B are the most common. The A type has different H and N subtypes and you may hear about different strains, for example H1N1 (swine flu) and H5N1 (avian flu)

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62
Q

which groups of people are offered an influenza vaccine?

A

Aged 65
Young children
Pregnant women
Chronic health conditions such as asthma, COPD, heart failure and diabetes
Healthcare workers and carers

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63
Q

how does influenza present?

A

Fever
Coryzal symptoms
Lethargy and fatigue
Anorexia (loss of appetite)
Muscle and joint aches
Headache
Dry cough
Sore throat

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64
Q

how is influenza investigated?

A

viral nasal or throat swabs to virology lab for PCR naalysis

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65
Q

how is influenza managed?

A

public health monitor number of cases
if at risk of complications - ostelamivir within 48 hrs of sx to be effective
post exposure prophylaxis to higher risk

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66
Q

what are the possible complications of influenza?

A

Otitis media, sinusitis and bronchitis
Viral pneumonia
Secondary bacteria pneumonia
Worsening of chronic health conditions such as COPD and heart failure
Febrile convulsions (young children)
Encephalitis

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67
Q

what is the most common cause of gastroenteritis?

A

viral

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68
Q

what are the viral causes of gastroenteritis?

A

rotavirus
norovirus
adenovirus

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69
Q

how is e.coli spread and how does it work/

A

infected faeces, unwashed salads or water
produces shiga toxin - abdo cramps, bloody diarrhoea and vomit
destroys red blood cells and can lead to haemolytic uraemic syndrome (and use of abx increases risk)

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70
Q

what is the causes of travellers diarrhoea and how is it spread?

A

campylobacter
Raw or improperly cooked poultry
Untreated water
Unpasteurised milk

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71
Q

what is the incubation periods and symptoms of campylobacter?

A

Incubation is usually 2-5 days. Symptoms resolve after 3-6 days. Symptoms are:

Abdominal cramps
Diarrhoea often with blood
Vomiting
Fever

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72
Q

how is campylobacter treated and in which circumstances?

A

severe sx or HIV, HF
azithromycin

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73
Q

how does shigella spread and what are the sx?

A

faeces contaminated water, pools and food
inc per - 1-2 days
blood diarrhoea, cramps, fever
shiga toxin - haemolytic uraemic syndrome

74
Q

how is shigella treated?

A

azithromycin

75
Q

how does salmonella spread and what are the sx?

A

ting raw eggs or poultry and food contaminated with infected faeces of small animals
Inc - 12 hrs to 3 days
watery diarrhoea wirh mucus/blood, abdo pain, vomit

76
Q

how does bacilus cereus spread?

A

inadequate cooked food - fried rice usually

77
Q

how does bacilus cereus cause its symptoms?

A

toxin called cereulide
abdo pain, cramp, vomit within 5 hours of ingestion
water diarrhoea after 8 hrs
recovers within 24 hrs
can also cause endocarditis in IVDU

78
Q

how does yersinia enterocolitica spread?

A

pigs - raw or undercooked pork
urine, or faces from rats orrabbits

79
Q

what are the sx of yersinia enterocolitica?

A

watery or bloody diarrhoea
abdo pain
fever
lymphadenopathy
sx last 3 weeks or more
older children or afults - right sided abdo pain from mesenteric lymphadenitis
fever
presents similar to appendicitis

80
Q

how does staph aureus cause gastroenteritis?

A

enterotoxins when growing in food such as eggs, dairy or meat…cause small intestine inflammation
diarrhoea, vomit, cramps, fever
lasts 24 hrs

81
Q

how does giardia lamblia spread and what are the sx?

A

lives in small intestines of mammals
releases cysts in the stools of infected mammals which contaminate food of water
faecal-oral trnamission
asx or chronic diarrhoea

82
Q

how is giardia lamblia diagnosed and treated?

A

stool microscopy
metronidazole

83
Q

what are the principles of gastroenteritis management

A

good hygeine
infection control
faces tested with microscopy, culture and sensitivity
dehydration assesment
slowly introduce light diet
off work/school for 48 hours after sx resolved
antidiarrhoea meds - loperamide
antiemetic - metoclopramide
Antidiarrhoeals should be avoided in e. coli 0157 and shigella infections and where there is bloody diarrhoea or high fever.
Antibiotics should only be given in patients that are at risk of complications and once the causative organism is confirmed.

84
Q

what are the possible post gastroenteritis complications?

A

Lactose intolerance
Irritable bowel syndrome
Reactive arthritis
Guillain–Barré syndrome

85
Q

define meningitis

A

inflammation of the meninges due to bacterial or viral infection

86
Q

define meningococcal septicaemia and how does it present?

A

bacterial infection in the bloodstream
non blanching rash - disseminated intravascular coagulopathy and subcutaneous haemorrhages

87
Q

what are the most common causes of bacterial meningitis?

A

neisseria mengitidis
strep pneumonia
neonates - group B strep

88
Q

how does meningitis present?

A

fever, stiffness, vomit, headache, photophobia, altered consciosuness, seizures
if septicaemia - non blanching rash
babies - hypotnia, poor feeding, lethargy, hypothermia, bulging fontanelles

89
Q

how do children with possible meningitis need t be investigated?

A

lumbar puncture -
under 1 month with fever
1-3 months with fever and unwell
under 1 year with unxplained fever and features of illness

90
Q

which two tests can be used to investigate bacterial meningitis (meningeal irritation)?

A

kernig’s - lying the patient on their back, flexing one hip and knee to 90 degrees and then slowly straightening the knee whilst keeping the hip flexed at 90 degrees. This creates a slight stretch in the meninges and where there is meningitis will produce spinal pain or resistance to this movement.
brudzinski’s test - s lying the patient flat on their back and gently using your hands to lift their head and neck off the bed and flex their chin to their chest. A positive test is when this causes the patient to involuntarily flex their hips and knees.

91
Q

how are children managed with bacterial meningitis?n the community

A

suspected meningitis AND a non blanching - urgent stat injection (IM or IV) of benzylpenicillin prior to transfer to hospital-
< 1 year – 300mg
1-9 years – 600mg
> 10 years and adults – 1200mg
This shouldn’t delay transfer to hospital

92
Q

which investgations are required for meningitis?

A

blood culture
lumbar puncture for CSF
blood test for meningococcal PCR - quicker than culture

93
Q

how is bacterial meningitis managed in hospital?

A

< 3 months – cefotaxime plus amoxicillin (the amoxicillin is to cover listeria contracted during pregnancy from the mother)
> 3 months – ceftriaxone
Vancomycin should be added if risk of penicillin resistant pneumococcal infection - recent foreign travel or prolonged antibiotic exposure.

Steroids are also used to reduce the frequency and severity of hearing loss and neurological damage - Dexamethasone

Bacteria meningitis and meningococcal infection are notifiable diseases to public health

94
Q

when is the risk highest of contracting bacterial meningitis and how is the risk minimised?

A

close prolonged contact within 7 days prior to onset of illness
- single dose of ciprofloxacin

95
Q

what are the most common causes of viral meningitis?

A

herpes simples virus
enterovirus
varicella zster virus

96
Q

how is viral meningitis investigated?

A

viral PCR

97
Q

how is viral meningitis treated?

A

aciclovir

98
Q

how does lumbar puncture work?

A

needle inserted into L3-4
samples sent for culture, viral PCR, protein and glucose
blood glucose also sent

99
Q

how is CSF result interpretated?

A

Bacterial
Viral
appearance
Cloudy
Clear
Protein
High
Mildly raised or normal
Glucose
Low
Normal
White Cell Count
High (neutrophils)
High (lymphocytes)
Culture
Bacteria
Negative

100
Q

what are the complications of meningitis?

A

Hearing loss is a key complication
Seizures and epilepsy
Cognitive impairment and learning disability
Memory loss
Focal neurological deficits such as limb weakness or spasticity

101
Q

how is TB stained?

A

mycobacterium tuberculosis - resistant to the acids used in the staining procedure - acid fastness. require a special staining technique using the Zeihl-Neelsen stain. This turns TB bacteria bright red against a blue background.

102
Q

what are the risk factors for TB?

A

non UK born patients - south asia
immunocompromised - HIV
Known contact with active TB
People with relatives or close contacts from countries with a high rate of TB
Homeless people, drug users or alcoholics

103
Q

how does TB spread?

A

inhaling saliva droplets

104
Q

what containing the bacteria forms around the body in TB?

A

granuloma

105
Q

define active TB vs latent Tb vs secondary vs miliary

A

active infection
when immune system stops progression of disease - latent
when latent tb reactivates - secondary
when immune system unable to control disease - miliary

106
Q

what are the sites of extrapulmonary TB?

A

Lymph nodes. A “cold abscess” is a firm painless abscess caused by TB, usually in the neck. They do not have the inflammation, redness and pain you would expect from an acutely infected abscess.
Pleura
Central nervous system
Pericardium
Gastrointestinal system
Genitourinary system
Bones and joints
Cutaneous TB affecting the skin

107
Q

what vaccine is used for TB?

A

BCG - intradermal infection of live attenuated TB
less effective at pulmonary TB, but good at severe and complicated

108
Q

how are patients tested prior to vaccine

A

mantoux test - given vaccine only if test is negative
also assessed for the possibility of immunosuppression and HIV due to the risks related to a live vaccine

109
Q

who is BCG vaccine offered to?

A

Neonates born in areas of the UK with high rates of TB
Neonates with relatives from countries with a high rate of TB
Neonates with a family history of TB
Unvaccinated older children and young adults (< 35) who have close contact with TB
Unvaccinated children or young adults that recently arrived from a country with a high rate of TB
Healthcare workers

110
Q

what are the signs and sx of TB?

A

Lethargy
Fever or night sweats
Weight loss
Cough with or without haemoptysis
Lymphadenopathy
Erythema nodosum
Spinal pain in spinal TB (also known as Pott’s disease of the spine)

111
Q

which two tests are used to investigated TB?

A

mantoux test - if pos indicated previous vaccination, latent or active TB. involves Injecting the tuberculin creates a bleb under the skin. After 72 hours the test is “read”. This involves measuring the induration of the skin at the site of the injection. an induration of 5mm or more a positive result.
interferon-gamma release assays - taking a sample of blood and mixing it with antigens from the TB bacteria. In a person that has had previous contact with TB - interferon-gamma is released from the white blood cells then this is considered a positive result.

The IGRA test is used in patients that do not have features of active TB but do have a positive Mantoux test to confirm a diagnosis of latent TB.

112
Q

what is seen in a chest x ray of TB?

A

Primary TB - patchy consolidation, pleural effusions and hilar lymphadenopathy
Reactivated TB - patchy or nodular consolidation with cavitation (gas filled spaces in the lungs) typically in the upper zones
Disseminated Miliary TB give a picture of “millet seeds” uniformly distributed throughout the lung fields

113
Q

how can a culture be used in the treatment of TB?

A

tests for bacterial resistance to abx- but takes times so started first
- Sputum. 3 samples should be collected and tested. If they are not producing sputum then hypertonic saline can be used to induce sputum that can be collected. They might require bronchoscopy with lavage to collect sputum samples.
Mycobacterium blood cultures. These require special blood culture bottle.
Lymph node aspiration or biopsy

114
Q

what are the pros and cons of performing NAAT rather than just culture?

A

provides information about the bacteria faster than a traditional culture but is only used where having this information would affect treatment or they are at higher risk of developing complications

115
Q

how is latent TB managed?

A

only if at risk of reactivation - isoniazid and rifampicin for 3 months or isoniazid for 6 months

116
Q

how is acute pulmonary TB treated?

A

R – Rifampicin for 6 months
I – Isoniazid for 6 months
P – Pyrazinamide for 2 months
E – Ethambutol for 2 months

117
Q

what is a consequence of isoniazid and what will need to be prescribed to prevent his?

A

peripheral neuropathy - pyridoxine

118
Q

how else is TB managed?

A

Test for other infectious diseases (HIV, hepatitis B and hepatitis C).
Test contacts for TB.
Notify Public Health of all suspected cases.
Patients with active TB should be isolated to prevent spread until they are established on treatment (usually 2 weeks). In hospital negative pressure rooms are used to prevent airborne spread.
specialist MDT.
Individualised drug regimes are required for multidrug‑resistant TB.

119
Q

ow is extrapulmonary TB managed?

A

usually with corticosteroids

120
Q

what are the side effects and drug drug reactions of rifampicin?

A

red orange urine and tears
inducer of P450 - reduces effect of some drugs like POCP

121
Q

what are the side effects of pyrazinamide?

A

hyperuricaemia - gout

122
Q

what are the side effects of ethambutol?

A

colour blindness and reduced visual acuity

123
Q

what side effects are common of rifampicin, isoniazid, pyrazinamide?

A

hepatotoxicity

124
Q

define HIV

A

human immunodeficiency virus
RNA retrovirus
HIV-1 and HIV-2, 1 is most common
virus enters and destroys CD4 T helper cells

125
Q

how can HIV spread?

A

Unprotected anal, vaginal or oral sexual activity.
Mother to child at any stage of pregnancy, birth or breastfeeding - vertical transmission.
Mucous membrane, blood or open wound exposure to infected blood or bodily fluids such as through sharing needles, needle-stick injuries or blood splashed in an eye.

126
Q

what is AIDS defined by and the associated conditions?

A

end stage HIV where CH4 dropped to level that opporunistic infections/malignancies can develop -
Kaposi’s sarcoma
Pneumocystis jirovecii pneumonia (PCP)
Cytomegalovirus infection
Candidiasis (oesophageal or bronchial)
Lymphomas
Tuberculosis

127
Q

how reliable are antibody tests?

A

Antibody tests can be negative for 3 months following exposure so repeat testing is necessary if an initial test is negative within 3 months of a potential exposure.

128
Q

what is important for testing HIV?

A

consent and documented

129
Q

what are the 3 types of tests that are used for HIV?

A

antibody blood test
p24 antigen in blood
PCR testing in blood (also give viral load)

130
Q

how is HIV progression and treatment monitored?

A

CD4 count -
500-1200 cells/mm3 is the normal range
Under 200 cells/mm3 is considered end stage HIV / AIDS and puts the patient at high risk of opportunistic infections

131
Q

what is the aim of hiv treatment?

A

undetectable viral load <100 copies/ml
normal CD4 count

132
Q

how is HIV treated?

A

atiretroviral therapy medications
Some regimes involve only a single combination tablet once per day but usually 2 NRTIS plus a third agent

133
Q

what are the classes of medications used to treat HIV?

A

Protease Inhibitors (PIs)
Integrase Inhibitors (IIs)
Nucleoside Reverse Transcriptase Inhibitors (NRTIs)
Non-Nucleoside Reverse Transcriptase Inhibitors (NNRTIs)
Entry Inhibitors (EIs)

134
Q

what prophylactic treatment can be offered and what does it protect against?

A

co-trimoxazole (septrin) - PCP

135
Q

what other monitoring is required for people with HIV as their risk increases?

A

CVD - lipids and may be given statins
yearly cervical smears - HPV
influenza, pneumococca, hep A and B, tetanus, diptheria, polio - vaccinations

136
Q

what reproductive advice must be given to people with HIV?

A

condoms and regular HIV tests - although if undetectable load very unlikely
can have unprotected sex and pregnancy or may choose sperm washing and IVF
Caesarian section unless mother has undetectable viral load
newborns to HIV pos mother - ART for 4 weeks after birth
breastfeeding considered if viral load undetecatble but still risk

137
Q

what is post exposure prophylaxis and what does it involve?

A

after exposure to HIV to reduce risk
within 72 hrs
risk assessment should be carried out of risk of developing it and the side effects of prophylaxis
combination of ART therapy - Truvada (emtricitabine / tenofovir) and raltegravir for 28 days.

HIV tests should be done initially but also a minimum of 3 months after exposure to confirm a negative status - no unprotected sex while waiting

138
Q

what is the most severe member of the protozoa causing malaria?

A

Plasmodium falciparum

139
Q

how does malaria spread?

A

female anopheles mosquito bites

140
Q

what are the types of plasmodium causing malaria?

A

Plasmodium falciparum
Plasmodium vivax
Plasmodium ovale
Plasmodium malariae

141
Q

what is malaria’s life cycle?

A

spread through anopheles
infected blood sucked up and the malaria in the blood reproduces in the gut of the mosquito producing sporozoites
when bites another human or animal - sporozoites injected and travel to liver and lie dorman as hyponozoites
matures in the liver into merozoites which enter blood and infect red cells, and repdouce and rupture releasing more merozoites into blood causing haemolytic anaemia

142
Q

how does malaria present?

A

Non-specific Symptoms
Fever, sweats and rigors
Malaise
Myalgia
Headache
Vomiting

Signs
Pallor due to the anaemia
Hepatosplenomegaly
Jaundice as bilirubin is released during the rupture of red blood cells

143
Q

how is malaria diagnosed?

A

malaria blood film sent in EDTA bottle
3 samples over 3 days to exclude malaria as malaria cycle is every 48 hrs

144
Q

how is malaria managed?

A

admitted as can deteriorate
Oral options in uncomplicated malaria:
Artemether with lumefantrine (Riamet)
Proguanil and atovaquone (Malarone)
Quinine sulphate
Doxycycline

Intravenous options in severe or complicated malaria:
Artesunate. This is the most effective treatment but is not licensed.
Quinine dihydrochloride

145
Q

what are the complications of falciparum?

A

Cerebral malaria
Seizures
Reduced consciousness
Acute kidney injury
Pulmonary oedema
Disseminated intravascular coagulopathy (DIC)
Severe haemolytic anaemia
Multi-organ failure and death

146
Q

what prophylaxis can be used for malaria?

A

Be aware of locations that are high risk
Use mosquito spray (e.g. 50% DEET spray) in mosquito exposed areas
Use mosquito nets and barriers in sleeping areas
Seek medical advice if symptoms develop
Take antimalarial medication as recommended

147
Q

what are the antimalarial medications available?

A

proguanil and atovaquone
mefloquine
doxycycline

148
Q

how is PCP treated?

A

Pneumocystis jiroveci penumonia is treated with co-trimoxazole

149
Q

legionellers

A

Legionella pneumophilia is best diagnosed by the urinary antigen test
Important for meLess important
The presence of a cough with fever, malaise, headaches, and crackles on auscultation should raise suspicion of pneumonia. The presence of hyponatraemia, lymphopenia, and mild ALT derangements, on the other hand, suggests that the pneumonia is caused by an atypical organism, in particular Legionella pneumophila.

150
Q

Syphillis

A

Syphilis: intramuscular benzathine penicillin is first-line

151
Q

What are some unusual sx of pneumonia caused by strep pneumonia?

A

Cold sores

152
Q

Msu indication

A

An MSU should be sent for all women over > 65-years-old with a suspected urinary tract infection

153
Q

throat infections and lymph node infiltration

A

There are a few conditions which can cause generalised lymphadenopathy which is mentioned in the question - CMV and Infectious mononucleosis (IM) are two of them. However, given the history and presence of large swollen tonsils together with a palpable mass in the left hypochondriac regions which suggests splenomegaly, it is highly suggestive of IM. Tonsillitis, viral throat infection, and dengue fever do not present with generalised lymphadenopathy nor splenomegaly.

154
Q

viral mengintiis suspected

A

if LP can not be performed - IV ceftraxione

155
Q

how is HIV tested?

A

Combination tests (HIV p24 antigen and HIV antibody) are now standard for the diagnosis and screening of HIV

156
Q

toxoplasmosis

A

Immunocompetent patients with toxoplasmosis don’t usually require treatment
Toxoplasmosis is a parasitic disease whose main reservoir is cats. It is caused by Toxoplasmosis gondii protozoa. It can cause a flu-like illness in humas with symptoms of malaise, lymphadenopathy and myalgia or may be asymptomatic. Most healthy individuals will clear the infection but it can cause complications such as anaemia, seizure or chorioretinitis. These complications mainly occur in neonates (born to mothers with acute infection) or immunocompromised patients.

157
Q

what are the clinical features of pneumonia jiorveci?

A

Pneumocystis jiroveci commonly presents desaturation on exertion and often Chest x-ray appears normal. It almost exclusively happens in immunosuppressed patients. Eswatini has one of the highest prevalences of HIV in the world (source WHO), making it relevant in this particular scenario. The patient has had recurrent chest infections which in such a young patient should be suggestive of immunosuppression.

158
Q

BV tx

A

metronidazole BD for 5 days oral +doxy + ceftraxione

159
Q

if CD4 count <200 HIV tx

A

All patients with a CD4 count lower than 200/mm3 should receive prophylaxis against Pneumocystis jiroveci pneumonia - co-trimoxazole

160
Q

what are the incubation periods of different causes of gastroenteritis?

A

1-6 hrs: Staphylococcus aureus, Bacillus cereus*
12-48 hrs: Salmonella, Escherichia coli
48-72 hrs: Shigella, Campylobacter
> 7 days: Giardiasis, Amoebiasis

161
Q

what bacteria that causes gastroenteritis mimics an appendicitis and can cause guillian-barre syndrome?

A

campylobacter

162
Q

what is the abx of choice for gonorrhoea?

A

IM ceftraxione

163
Q

what is the abx of choice for extensive otitis externa?

A

flucloxacillin

164
Q

meningitis

A

The BNF recommend IV cefotaxime (or ceftriaxone) + amoxicillin (or ampicillin) as empirical therapy for adults > 50 years with suspected bacterial meningitis

165
Q

human bites tx

A

Human bites, like animal bites, should be treated with co-amoxiclav

166
Q

syphilis tx

A

Syphilis: intramuscular benzathine penicillin is first-line

167
Q

meningitis exposure

A

People who have been exposed to a patient with confirmed bacterial meningitis should be given prophylactic antibiotics if they have close contact within the seven days before onset

168
Q

chlamydia in pregnant women

A

Chlamydia trachomatis in pregnant and breastfeeding women should be treated with azithromycin

169
Q

prostatis

A

ciprofloxacin

170
Q

how is glucose affected by bacterial meningitis?

A

In bacterial meningitis, the CSF glucose is typically less than half the serum glucose

171
Q

what is the most likely causative organism of pneumonia in alcoholics?

A

kleisbella

172
Q

typhoid

A

A relative bradycardia, also known as Faget’s sign, is a recognised sign of typhoid fever. It is defined as a heart rate that is slower than expected for the degree of fever. This patient’s fever is reaching 40.4ºC, so one would expect a heart rate faster than 59 beats per minute.

173
Q

ebola inc period

A

2-21 days

174
Q

uti abx if breastfeeding

A

trimethoprim

175
Q

neutropenic sepsis

A

NICE guidelines for neutropenic sepsis (2016) state that neutropenic sepsis should be suspected in a person with a known cause for neutropenia (recent cancer treatment), presumed or confirmed infection, temperature >38ºC and respiratory rate >20 breaths per minute.

176
Q

preceding influenza prediposes to

A

Preceding influenza predisposes to Staphylococcus aureus pneumonia

177
Q

hep e

A

Hepatitis E is spread by the faecal-oral route and is most commonly spread by undercooked pork

178
Q

syphillus v herpes v behcet;s

A

syphilis - painless
herpes - painful and associated flu
behcets - triad of uevitis, ulcers in mouth and vagina

179
Q

what is the first line treatment of syphilis?

A

intramuscular benzathine penicillin is first-line

180
Q

adrenaline dose for anaphylaxis/allergy

A

IM 1:1000 500 micrograms

181
Q

trichomonas vaginalis

A

A strawberry cervix is associated with Trichomonas vaginalis, a condition which may present in a similar fashion to bacterial vaginosis