Infectious diseases Flashcards
features of acute pyelonephritis
ascending infection (typically E. coli from the lower urinary tract
fever, rigors
loin pain
nausea/vomiting
symptoms of cystitis may be present:
dysuria
urinary frequency
treatment of acute pyelonephritis
signs of acute pyelonephritis - hospital admission
broad-spectrum cephalosporin or a quinolone (non-pregnant) - for 7-10 days
causes of amoebiasis
entamoeba histolytica (an amoeboid protozoan)
spread by the faecal-oral route
can be asymptomatic, cause mild diarrhoea or severe amoebic dysentery, can cause liver and colonic abscesses
features of amoebic dysentry
profuse, bloody diarrhoea
there may be a long incubation period
stool microscopy may show trophozoites if examined within 15 minutes or kept warm (known as a ‘hot stool’)
treatment
oral metronidazole
a ‘luminal agent’ (to eliminate intraluminal cysts) is recommended usually as well e.g. diloxanide furoate
features of amoebic liver abscess
single mass in the right lobe (may be multiple)
features
fever
right upper quadrant pain
systemic symptoms e.g. malaise
hepatomegaly
positive serology, USS
oral metronidazole
a ‘luminal agent’ (to eliminate intraluminal cysts) is recommended usually as well e.g. diloxanide furoate
management of animal bites
generally polymicrobial but the most common isolated organism is Pasteurella multocida
cleanse wound
co-amoxiclav
if penicillin-allergic then doxycycline + metronidazole is recommended
causes and management of human bites
Common organisms include:
Streptococci spp.
Staphylococcus aureus
Eikenella
Fusobacterium
Prevotella
co-amoxiclav
consider risk of viral infections such as HIV and hepatitis C
features of anthrax
caused by Bacillus anthracis, a Gram positive rod, spread by infected carcasses
Features
causes painless black eschar (cutaneous ‘malignant pustule’, but no pus)
typically painless and non-tender
may cause marked oedema
anthrax can cause gastrointestinal bleeding
management of anthrax
ciprofloxacin
indications and moa of amphotericin b
Used for systemic fungal infections
indications and moa of terbinafine
Commonly used in oral form to treat fungal nail infections
indications and moa of nystatin
As very toxic can only be used topically (e.g. for oral thrush)
features of aspergilloma
a mycetoma (mass-like fungus ball) which often colonises an existing lung cavity (e.g. secondary to tuberculosis, lung cancer or cystic fibrosis)
asymptomatic, cough, haemoptysis
effects of b. cereus poisoning
symptoms typically resolve within 24 hours in both syndromes
casuses diarrhoea and crampy abdominal pain
diagnosis of bacterial vaginosis
Amsel’s criteria for diagnosis of BV - 3/4 present
thin, white homogenous discharge
clue cells on microscopy: stippled vaginal epithelial cells
vaginal pH > 4.5
positive whiff test (addition of potassium hydroxide results in fishy odour)
management of bacterial vaginosis
if asymptomatic - no need for treatment
if symptomatic - oral metronidazole for 5-7 days, >50% relapse rate <3m
if pregnant - topical clindamycin
features of botulism
Clostridium botulinum - may result from eating contaminated food (e.g. tinned) or intravenous drug use
neurotoxin often affects bulbar muscles and autonomic nervous system
Features
patient usually fully conscious with no sensory disturbance
flaccid paralysis
diplopia
ataxia
bulbar palsy
treatment of botulism
botulism antitoxin and supportive care
antitoxin is only effective if given early - once toxin has bound its actions cannot be reversed
features of campylobacter infection
commonest bacterial cause of infectious intestinal disease in the UK
spread by the faecal-oral route and has an incubation period of 1-6 days
prodrome: headache malaise
diarrhoea: often bloody
abdominal pain: may mimic appendicitis
managment of campylobacter
first-line antibiotic is clarithromycin
features of cat scratch disease
generally caused by the Gram negative rod Bartonella henselae
Features
fever
history of a cat scratch
regional lymphadenopathy
headache, malaise
features of cellulitis
commonly occurs on the shins
usually unilateral
erythema
blisters and bullae may be seen with more severe disease
swelling
systemic upset
fever
malaise
nausea
what is a chancroid
caused by Haemophilus ducreyi
causes painful genital ulcers associated with unilateral, painful inguinal lymph node enlargement. The ulcers typically have a sharply defined, ragged, undermined border.
features of chlamydia
asymptomatic in around 70% of women and 50% of men
women: cervicitis (discharge, bleeding), dysuria
men: urethral discharge, dysuria