Ed's microbiology Flashcards

1
Q

What is the appropriate antibiotic for low severity (CURB65 score 0-1) CAP?

A
  • doxycycline
  • alternatives: amoxicillin or clarithryomycin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is the appropriate antibiotic for mod/severe (CURB65 score 2-5) CAP?

A
  • benzyl penicillin IV and
  • doxycycline PO
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is the appropriate antibiotic management for infective exacerbation of COPD?

A
  • doxycline
  • alternative: clarithromycin or amoxicillin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the antibiotic management for uncomplicated UTI?

A
  • nitrofurantoin
  • women = 3 days, men = 7 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the appropriate antibiotic management for non-severe tissue infection?

A
  • flucloxacillin PO
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is the appropriate antibiotic management for severe soft tissue infection?

A
  • flucloxacillin IV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Broad-spectrum antibiotics suppress the normal gut flora. Which bacteria does this allow to develop and how does it cause damage?

A
  • Clostridium difficile
  • gram-positive rod
  • produces exotoxin -> causes intestinal damage
  • leading to syndrome called pseudomembranous colitis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is now the leading cause of C. Diff infection?

A
  • second + third generation cephalosporins
  • eg. ceftriaxone, cefotaxime, cefoxitin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How is diagnosis of C. Diff infection made?

A
  • Stool sample detecting toxin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the management of C. Diff infection?

A
  • oral metronidazole
  • 10-14 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe the rash often associated with meningococcal septicaemia/meningitis

A
  • petechial or purpuric rash is typically associated w/ meningococcal meningitis
  • a rash is noted in 80% to 90% of patients
  • most commonly 4-18 hours after initial symptoms of illness
  • typically, rash is non-blanching petechial or purpuric
  • but a few patients may initially have non-specific erythematous macular rash
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the immediate management of the septic patient?

A

SEPSIS 6 - GIVE 3, TAKE 3

  1. administer oxygen -> aim sats >94%
  2. take blood cultures
  3. give broad spectrum antibiotics -> co-amoxiclav IV + amikacin IV
  4. give IV fluid challenges
  5. measure serum lactate
  6. measure accurate hourly urine output
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is the definition of pyrexia of unknown origin (PUO)?

A
  • a temperature >38.3 for >3weeks
  • with no obvious source
  • despite appropriate investigations
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are infectious causes of PUO?

A
  • abscesses (lung, liver, pelvic)
  • empyema
  • rheumatic fever
  • tuberculosis
  • parasites (malaria)
  • fungi
  • septicaemia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are neoplasmic causes of PUO?

A
  • lymphomas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What connective tissue disorders might cause PUO?

A
  • rheumatoid arthritis
  • polymyalgia rheumatica
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are other (not infections, neoplasms or connective tissue disorders) causes of PUO?

A
  • drugs
  • PE
  • IBD
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What investigations would you like to do for common STIs?

A
  • detailed examination of genitalia
  • urine dipstick and MC+S
  • ulcers -> swab for HSV
  • urethral smear -> gonorrhoea
  • urethral swab -> chlamydia
  • blood tests -> syphillis, hepatitis + HIV
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the most prevalent sexually transmitted infection in the UK?

A
  • chlamydia
  • approx 1 in 10 young women in UK have it
  • incubation period = 7-21 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are features of chlamydia?

A
  • asymptomatic in around 70% of women + 50% of men
  • women: cervicitis (discharge, bleeding), dysuria
  • men: urethral discharge, dysuria
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The investigation of choice for chlamydia is a urethral swab. What are potential complications of chlamydia?

A
  • epididimytis
  • PID
  • endometritis
  • infertility
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is the management of chlamydia?

A
  • doxycycline (7days)
  • or azithromycin (single dose)
  • if pregnant -> azithromycin, erythromycin or amoxicillin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What are features of the gonorrhoea bacterium?

A
  • neisseria gonorrhoea
  • gram negative diplococcus
  • incubation period = 2-5 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are clinical features of gonorrhoea?

A
  • males -> urethral discharge, dysuria
  • females -> cervicitis eg. leading to vaginal discharge
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What are potential complications of gonorrhoea?

A
  • urethral strictures
  • epididimytis
  • salpingitis (-> infertility)
  • DIC
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the management of gonorrhoea?

A
  • cephalosporins -> ceftriaxone (500mg IM single dose)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Syphillis is an STI that is characterised by primary, secondary and tertiary stages. What are these stages?

A
  • primary -> painless ulcer at site of sexual contact, local non-tender lymphadenopathy
  • secondary (6-10wks after primary infection) -> fevers, lymphadenopathy, rash on trunk, palm + soles
  • tertiary -> granulomatous lesions of skin + bones, ascending aortic aneurysms, ‘general paralysis of the insane’
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is the incubation period for syphillis?

A
  • 9-90 days
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the antibiotic management of syphillis?

A
  • benzylpenicillin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

How might Herpes Simplex present clinically?

A
  • primary infection may present w/ severe gingivostomatitis (inflammation of oral mucosa)
  • cold sores
  • painful genital ulceration
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

What is the antibiotic management of herpes simplex?

A

for both gingivostomatitis and genital herpes:

  • oral aciclovir
32
Q

A common cause of attendance at GUM clinic would be genital warts. What are these caused by?

A
  • caused by many varieties of HPV
  • type 16 and 18 predisposes to cervical cancer
33
Q

What do genital warts look like?

A
  • small fleshy protuberances which are slightly pigmented
34
Q

What is the management of genital warts?

A
  • topical podophyllum or cyrotherapy
35
Q

How does thrush (candida albicans) present?

A
  • commonest cause of discharge
  • classically described as white curds
  • vulva + vagina may be red, fissured + sore
36
Q

What is the management of thrush?

A
  • clotrimazole pessary
37
Q

How does bacterial vaginosis present clinically?

A
  • causes fishy smelling discharge
  • vagina is not inflammed
38
Q

What is the antibiotic management of bacterial vaginosis?

A
  • oral metronidazole (5-7 days)
  • 70-80% initial cure rate
  • relapse rate >50% within 3 months
39
Q

What is pelvic inflammatory disease (PID)?

A

Term used to describe infection and inflammation of the female pelvic organs including the uterus, fallopian tubes, ovaries and the surrounding peritoneum

It is usually the result of ascending infection from the endocervix

40
Q

What are causative organisms for PID?

A
  • chlamydia trachomatis - most common cause
  • neisseria gonorrhoea
  • mycoplasma genitalium
  • mycoplasma hominis
41
Q

What are clinical features of PID?

A
  • lower abdo pain
  • fever
  • deep dyspareunia
  • dysuria + menstrual irregularities may occur
  • vaginal or cervical discharge
  • cervical excitation
42
Q

What is the investigation for PID?

A
  • screen for chlamydia and gonorrhoea
43
Q

What is the antibiotic management of PID?

A
  • oral ofloxacin
  • oral metronidazole
44
Q

What are complications of PID?

A
  • infertility
  • chronic pelvic pain
  • ectopic pregnancy
45
Q

What are the life-threatening complications of malaria?

A
  • AKI - usually due to dehydration + hypovolaemia, can also be due to acute tubular necrosis in severe disease
  • hypoglycaemia - common w/ severe disease + may be worsened by quinine therapy, preg women are most at risk
  • severe anaemia - most common in young children due to direct red cell lysis
  • DIC - bleeding gums, epistaxis + petechiae in severe disease
  • septicaemia
  • seizure or other CNS complications
46
Q

What are risk factors for typhoid fever?

A
  • overcrowded living in endemic areas (eg. india)
  • poor sanitation/untreated water in endemic areas
  • poor personal hygeine in endemic areas
47
Q

What are symptoms and signs of typhoid fever?

A
  • HIGH FEVER -> sometimes occurs in a stepwise fashion with 5-7 days of daily increments in max temp of 0.5 to 1 celcius
  • dull frontal headache
  • abdominal pain
  • anorexia
  • apathetic-lethargic state
  • constipation
  • cough
  • diarrhoea
  • malaise

Signs include rose spots (blanching erythematous maculopapular lesions) reported in 5-30% of cases; usually occurs on abdo + chest

48
Q

What are the 3 types of UTI?

A
  • infecious cystitis is the most common UTI, caused by bacterial infection of bladder
  • pyelonephritis is an infection of kidney often occurs via bacterial ascent
  • urethritis is an infection causing inflammation of the urethra
49
Q

What are risk factors for UTI?

A
  • sexual activity
  • spermicide use
  • post-menopause (absence of oestrogen)
  • positive FHx
  • history of recurrent UTI
  • presence of a foreign body
50
Q

What organisms cause UTI?

A
  • E. Coli is the cause in 70-95% of uncomplicated cases
  • Staph saprophyticus is cause in 5-20% of cases
  • broad range of bacteria cause complicated UTIs, many are resistant to multiple antimicrobial agents
51
Q

What are the clinical features of UTI, specifically for cystitis?

A
  • frequency of micturition by day and night
  • painful voiding (dysuria)
  • suprapubic pain + tenderness
  • haematuria
  • smelly urine

these symptoms relate to bladder + urethral inflammation, commonly called ‘cystitis’ + suggest lower urinary tract infection

52
Q

Which symptoms would suggest extension of the infection to the pelvis and kidney, ie. pyelonephritis?

A
  • loin pain + tenderness
  • fever
  • systemic upset
53
Q

In whom is it important to always bear in mind the possibility of UTI and why?

A
  • in small children
  • cannot complain of dysuria
  • symptoms often ‘atypical’
  • possibility of UTI must always be considered in the freful, febrile child who fails to thrive
54
Q

Which investigations are important for UTI?

A
  • urine dipstick -> most effective in UTI w/ high bacterial count, diagnosis better if used in combo with other tests. Results = nitrite + leukocyte esterase positive
  • urine microscopy -> used to confirm organism type + guide antibiotic selection in complicated UTI or pyelonephritis. Result = bacteria, WBC, possibly RBC
  • urine culture + sensitivity -> most specific and sensitive test. Result = growth of >105 CFU/mL
55
Q

What is the management of uncomplicated UTI (where there is normal renal tract + function)? How long is this for?

A
  • nitrofurantoin 50mg PO 6hourly
  • women -> 3 days
  • men -> 7 days
  • alternatives: 3day course of trimethoprim/sulfamethoxazole
56
Q

What is the management of complicated UTI (abnormal renal/GU tract, voiding problems, virulent organism) and/or pyelonephritis?

A
  • co-amoxiclav IV 1.2g, 8hrly
  • then oral when afebrile
  • complete 7-day course
57
Q

Abacteriuric frequency or dysuria can be termed ‘urethral syndrome’. What are causes of abacteriuric dysuria?

A
  • postcoital bladder trauma
  • vaginitis
  • atrophic vaginitis
  • urethritis (in elderly)
  • interstitial cystitis

In symptomatic young women w/ ‘sterile pyuria’, chlamydia infection and tuberculosis must be excluded.

58
Q

What are the 3 clinical manifestations of herpes simplex virus?

A
  • cold sores
  • painful genital ulceration
  • severe gingivostomatitis
59
Q

How does herpes zoster manfiest clinically?

A
  • AKA shingles
  • acute, unilateral painful blistering rash
  • caused by reactivation of Varicella Zoster virus
60
Q

How does herpes simplex keratitis present?

A
  • presents w/ a dendritic corneal ulcer
  • leads to red and painful eye
61
Q

Infectious mononucleosis (glandular fever) is caused by EBV in 90% of cases. A classic triad of symptoms is seen in around 98% of patients. What is the triad?

A
  • sore throat
  • lymphadenopathy -> may present in anterior + posterior triangles of neck
  • pyrexia

Other features include malaise, anorexia, headache, splenomegaly and lymphocytosis

62
Q

Meningitis is the inflammation of the meninges usually caused by bacterial, viral or fungal infection. What are the signs and symptoms for this?

A
  • headache
  • nausea or vomiting
  • neck stiffness
  • fever
  • photophobia
  • confusion + seizures
63
Q

How do you diagnose meningitis?

A
  • lumbar puncture
  • blood culture in patients where LP is delayed
64
Q

What is the management of meningitis?

A

All patients should be transferred to hospital urgently

  • patients in pre-hospital setting (eg GP) -> IM benzylpenicillin
  • hospital -> ceftriaxone + aciclovir
65
Q

What is encephalitis?

A
  • inflammation of the brain parenchyma
  • associated w/ neurological dysfunction eg. altered state of consciousness, seizures, personality changes, cranial nerve palsies + speech problems
  • it is the result of direct inflammation of the brain tissue
  • as opposed to inflammation of the meninges
  • can be the result of infectious or non-infectious causes
66
Q

What are signs and symptoms of encephalitis?

A
  • fever -> seen in infectious causes
  • rash -> eg. vesicular eruption in HSV, erythema nodosum in TB
  • altered mental state
  • focal neurological deficit -> eg. aphasia, hemiparesis, ataxia
67
Q

How is diagnosis of encephalitis made?

A
  • lumbar puncture
  • bloods -> FBC, U+Es, LFTs, blood cultures
  • imaging -> CXR, CT brain

The treatment depends on the underlying cause

68
Q

What might cause CNS/cerebral abscesses?

A
  • extension of sepsis from middle ear or sinuses
  • trauma or surgery to scalp
  • penetrating head injuries
  • embolic events from endocarditis
69
Q

What are the signs + symptoms of a cerebral abscess?

A
  • presenting symptoms will depend upon site of abscess (those in critical areas eg. motor cortex will present earlier)
  • abscesses have a considerable mass effect in brain + raised ICP is common
  • although fever, headache + focal neurology are highly suggestive of a brain abscess, in the absence of 1+ of these does not exclude diagnosis
  • fever may be absent and even if present, is usually not the swinging pyrexia seen with abscesses at other sites
70
Q

How is diagnosis of cerebral abscess made?

A
  • assessment of patient includes imaging with CT scanning
71
Q

What is the management of a cerebral abscess?

A
  • treatment usually surgical
  • a craniotomy performed + abscess cavity debrided
  • the abscess may reform bc the head is closed following abscess drainage
72
Q

Which organisms are likely to cause meningitis in 6-60 year olds?

A
  • neisseria meningitidis
  • streptococcus pneumonia
73
Q

What changes in the CSF would suggest a diagnosis of viral, bacterial and TB meningitis?

A
74
Q

What are the indications for a lumbar puncture?

A
  • suspicion of meningitis
  • suspicion of subarachnoid haemorrhage (SAH)
  • suspicion of CNS diseases such as Guillain-Barre syndrome
75
Q

What are the possible complications of LP?

A
  • coning
  • introduction of infection into CSF
76
Q

What are the contraindications for lumbar puncture?

A
  • local skin sepsis
  • bleeding diatheses eg. anticoagulant therapy
  • signs of spinal cord compression
  • papilloedema or other signs of raised ICP
  • suspicion of intracranial or cord mass
  • congenital neurological lesions in lumbosacral region
  • coagulation abnormalities
  • after convulsions until stabilised