Microbiology Flashcards
Features of actinomycosis
Gram positive bacilli
Faculative anaerobes
Can cause multiple abcesses
May develop in appendix
Direct visualisation of organisms and sulphur granules from lesions themselves is the easiest way to make a diagnosis.
Diarrhoea with HIV
Cryptosporidium
Large tonsils, petechial haemorrhages, splenomegaly and test diagnosis
EBV
Monospot test
Organism causing genitourinary infection
E coli
Boy with recurrent pruitius ani, small worm organism
Enterobius vermicularis
Organism in septic arthritis for young adults
Neisseria gon
Necrotising fasciitis
Mainly polymicrobial
Further surgery 24-48hrs after initial surgery to review extension of infection
Muscles are relatively spared
Crepitus in 35%
Strep most common in isolation
Risk in diabetes
Floating stools and diarrhoea
Giardia lambilla
Causes of osteomyelitis in sickle
Salmonella
Features of salmonella type
Relative Brady
Rose spots on trunk
Constipation
What is the risk of wound infection in a laparoscopic cholecystectomy for uncomplicated biliary colic
4%
MOA of antibiotics
Cell wall- pen, ceph
Protein synthesis clindamycin 50, Oxala 50, amino 30, tetracycline 30, macrolides 50, linezolid 50
DNA synthesis- quinolones (cipro) dna gyrase, metronidazole, trimethoprim,
RNA- rifampicin
Hard painless ulcer cause
Treponema pallidum
Causes of Fourniers gangrene
E coli and bacteriodes
What is the risk of a wound infection in a male undergoing a Hartmanns procedure for perforated sigmoid diverticular disease?
35%
What is the likely risk of surgical wound infection in a 23 year old male undergoing an elective inguinal hernia repair?
Less than 5%
Abx for MSRA
vancomycin
teicoplanin
Some strains may be sensitive to the antibiotics listed below but they should not generally be used alone because resistance may develop:
rifampicin
macrolides
tetracyclines
aminoglycosides
clindamycin
Hepatits DNA/RNA
All RNA apart from Hep b which is double stranded DNA
Malignant otitis externa organism
Pseudomonas aeruginosa
Watercress, severe abdominal pain, fevers and progressive jaundice. Imaging with ultrasound shows mildly dilated bile ducts with hyperechoic areas
Fasciola hepatica
Treatment is with triclabendazole. Some patients may need ERCP
C jejuni features
Most common cause of acute infective diarrhoea
Spiral, gram negative rods
Usually infects caecum and terminal ileum. Local lymphadenopathy is common
May mimic appendicitis as it has marked right iliac fossa pain
Reactive arthritis is seen in 1-2% of cases
Diarrhoea, cyst on stool, immunocomprimsied
Cryptosporidium
Mx of infected prosthesis
Removal of metal work implantation of gentamicin beads and delayed revision is the mainstay of managing this complication after 4 weeks. In earlier infections, linear exchanges covered by prolonged courses of antibiotics can be used.
Cause of melanosis coli
Laxative abuse
Organism causing severe peiritoneal infections
Bacteriodes
Recently away, diarrhoea, with eggs and worms in stool
Ascaris lumbricoides
Enterobiasis diagnosis
Common cause of pruritus ani
Diagnosis usually made by placing scotch tape at the anus, this will trap eggs that can then be viewed microscopically
Most common organism in infective endocarditis with prev faulty heart valves e.g rheumatic fever
Strep viridans
Cause of quinsy
Strep pyogenes