Ed's microbiology Flashcards
What is the appropriate antibiotic for low severity (CURB65 score 0-1) CAP?
- doxycycline
- alternatives: amoxicillin or clarithryomycin
What is the appropriate antibiotic for mod/severe (CURB65 score 2-5) CAP?
- benzyl penicillin IV and
- doxycycline PO
What is the appropriate antibiotic management for infective exacerbation of COPD?
- doxycline
- alternative: clarithromycin or amoxicillin
What is the antibiotic management for uncomplicated UTI?
- nitrofurantoin
- women = 3 days, men = 7 days
What is the appropriate antibiotic management for non-severe tissue infection?
- flucloxacillin PO
What is the appropriate antibiotic management for severe soft tissue infection?
- flucloxacillin IV
Broad-spectrum antibiotics suppress the normal gut flora. Which bacteria does this allow to develop and how does it cause damage?
- Clostridium difficile
- gram-positive rod
- produces exotoxin -> causes intestinal damage
- leading to syndrome called pseudomembranous colitis
What is now the leading cause of C. Diff infection?
- second + third generation cephalosporins
- eg. ceftriaxone, cefotaxime, cefoxitin
How is diagnosis of C. Diff infection made?
- Stool sample detecting toxin
What is the management of C. Diff infection?
- oral metronidazole
- 10-14 days
Describe the rash often associated with meningococcal septicaemia/meningitis
- 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
What is the immediate management of the septic patient?
SEPSIS 6 - GIVE 3, TAKE 3
- administer oxygen -> aim sats >94%
- take blood cultures
- give broad spectrum antibiotics -> co-amoxiclav IV + amikacin IV
- give IV fluid challenges
- measure serum lactate
- measure accurate hourly urine output
What is the definition of pyrexia of unknown origin (PUO)?
- a temperature >38.3 for >3weeks
- with no obvious source
- despite appropriate investigations
What are infectious causes of PUO?
- abscesses (lung, liver, pelvic)
- empyema
- rheumatic fever
- tuberculosis
- parasites (malaria)
- fungi
- septicaemia
What are neoplasmic causes of PUO?
- lymphomas
What connective tissue disorders might cause PUO?
- rheumatoid arthritis
- polymyalgia rheumatica
What are other (not infections, neoplasms or connective tissue disorders) causes of PUO?
- drugs
- PE
- IBD
What investigations would you like to do for common STIs?
- detailed examination of genitalia
- urine dipstick and MC+S
- ulcers -> swab for HSV
- urethral smear -> gonorrhoea
- urethral swab -> chlamydia
- blood tests -> syphillis, hepatitis + HIV
What is the most prevalent sexually transmitted infection in the UK?
- chlamydia
- approx 1 in 10 young women in UK have it
- incubation period = 7-21 days
What are features of chlamydia?
- asymptomatic in around 70% of women + 50% of men
- women: cervicitis (discharge, bleeding), dysuria
- men: urethral discharge, dysuria
The investigation of choice for chlamydia is a urethral swab. What are potential complications of chlamydia?
- epididimytis
- PID
- endometritis
- infertility
What is the management of chlamydia?
- doxycycline (7days)
- or azithromycin (single dose)
- if pregnant -> azithromycin, erythromycin or amoxicillin
What are features of the gonorrhoea bacterium?
- neisseria gonorrhoea
- gram negative diplococcus
- incubation period = 2-5 days
What are clinical features of gonorrhoea?
- males -> urethral discharge, dysuria
- females -> cervicitis eg. leading to vaginal discharge
What are potential complications of gonorrhoea?
- urethral strictures
- epididimytis
- salpingitis (-> infertility)
- DIC
What is the management of gonorrhoea?
- cephalosporins -> ceftriaxone (500mg IM single dose)
Syphillis is an STI that is characterised by primary, secondary and tertiary stages. What are these stages?
- 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’
What is the incubation period for syphillis?
- 9-90 days
What is the antibiotic management of syphillis?
- benzylpenicillin
How might Herpes Simplex present clinically?
- primary infection may present w/ severe gingivostomatitis (inflammation of oral mucosa)
- cold sores
- painful genital ulceration