Question book 3 Flashcards
(36 cards)
Hospital food preparation policy is being revised. Which organism is able to grow up to 1x10power2 cfu/g in coleslaw?
E. coli Campylobacter Listeria Vibrio haemolyticum Salmonella Tyhpimurium
Listeria
Can grow between 0 and 45 degC, so can end up in prepared foods
Soft cheese, cooked meats, pate are risks
Risk to immunocompromised patients and pregnant staff
Outbreak of dirrhoea on medical ward - including patients and staff. Norovirus is the cause
What action should be taken
substitute cleaning solution with peroxygen compounds
substitute cleaning solution with 100000ppm chlorine
use liquid soap and warm water as per WHO 5 moments
use alcohol hand gel as per WHO 5 moments
use gloves, aprons, and masks for interactions with patients with diarrhoea
use liquid soap and warm water as per WHO 5 moments
Norovirus is non-enveloped - so resistant to alcohol hand wash
masks are useless as non-aerosolised
1000ppm chlorine is used for cleaning
Which operation would benefit from having procedure in laminar flow theatre?
brain biopsy renal transplant total knee replacement CABG open reduction and internal fixation of hip fracture
total knee replacement
Earlier evidence showed reduced surgical site infections in orthopaedic procedures.
However, this is under review as meta-analysis did not demonstrate as big an imapct
Operating theatres are being reconditioned and air quality must be checked.
How is this best achieved?
air sampling
environmental swabs
air filters swabs
quantification of air circulation per hour
epidemiological survey of patient infection rates
air sampling
can use agar as “settle” plates, which catch any bacteria in air
or can use active air sampler which uses air pump to direct air towards plates
Operating theatres are being reconditioned and air quality must be checked.
How is this best achieved?
air sampling
environmental swabs
air filters swabs
quantification of air circulation per hour
epidemiological survey of patient infection rates
air sampling
can use agar as “settle” plates, which catch any bacteria in air
or can use active air sampler which uses air pump to direct air towards plates
3 year old has fever, barking cough. Diagnosed with Croup
What is most common cause?
rhinovirus
RSV
parainfluenza
coronavirus
Parainfluenza
32 year old IVDU had popped heroin into left buttock 1 week ago
Presents with extending necrosis and swelling over left buttock and genitalia. Has fever and rigors.
Requires multi-organ support
What is most likely diagnosis?
Anthrax Fournier's gangrene Gas gangrene Type 1 (polymicrobial) necrotising fasciitis Clostridium sordellii
Anthrax
Anthrax associated with injection, does not behave like normal cutaneous anthrax - so does not produce an eschar
What are components of anthrax toxin?
oedema factor
lethal factor
protective factor
60 year old had mtiral valve repalcement 6 weeks previously.
Presents with fever, lethargy, SOB.
Prosthetic valve endocarditis suspected.
Gram pos bacilli grown on blood culture.
What is likely organism>
Corynebacterium jeikeium Corynebacterium striatum Staphylococcus epidermidis Arcanobacterium haemolyticum Corynebacterium pseudodiphteriticum
Corynebacterium pseudodiptheriticum
Early prosthetic valve infection is within 60 days of implantation.
Staph aureus and epidermidis are lower risk than Corynebacterium pseudodiptheriticum.
Other Corynebacterium species and Arcanobacterium cause infections in native valves, not prosthetic valve
44 year old with painful discharging lesions in scrotal region over months. Some improvement with courses of flucloxacillin and clindamicin.
Swabs have grown staph aureus
On examination there is scrotal swelling with erythema, which is tender. There are discharging lesions in tunnel-like formation with normal looking skin between lesions.
What is most likely diagnosis?
Abscesses caused by PVL staph aureus Cutaneous Crohn's disease Hidradenitis suppurativa Fournier's gangrene Steatocystoma multiplex
Hidradenitis suppurative
Recurrent suppurating lesions in apocrine gland-bearing regions, due to disease of hair follicles
Antibiotics can be beneficial, if superadded infection. Biologics can be used to reduce inflammation
35 year old on chemotherapy has fever, headache, photophobia. Known to be neutropenic
CSF suggests meningitis
TB PCR neg
Gram stain no orgnaisms
CT head - NAD
What is most likely cause?
TB Staph capitis Cryptococcus Candida auris Nocardia
Cryptococcus
TB unlikely as PCR neg
Staph capitis only causes meningitis in neonates
Candida auris - commonly causes line infections
Nocardia - would expect pulmonary symptoms/ lesions
What are the two types of amoebic encephalitis?
Primary amoebic meningoencephalitis - due to Naegleria fowleri. Water exposure with facial trauma
Granulomatous amoebic meningoencehalitis - Acanthomoeba and Balamuthia are more insidious in onset
42 year old with lump on face, and outer thigh.
Recent travel to Italy last year.
Biopsy of outer thigh lesion performed
What is the most likely diagnosis?
sarcoidoisis dirofilariasis loa loa penicilliosis cutaneous TB
dirofilariasis
zoonosis transmitted by mosquitoes. Dirofilaria end up in humans as dead end hosts - resulting in subcutaneous nodules most commonly
penicilliosis is from SE Asia
TB is unlikely distribution
sarcoidosis unlikely
loa loa - calabar swellings have different distribution
30 year old with fever, weight loss, mild abdominal pain.
Travelled across all the Americas, Africa and Asia.
CT abodemn reveleaed bilateral adrenal masses which were biopsied
Histopathology - granulomatous inflammation with histiocytes
TB PCR - neg
What is most likely cause of granulomatous disease?
Dirofilariasis TB Histoplasmosis Wegner's granulomatosis Sarcoidosis
Histoplasmosis
distribution in adrenal glands is suspicious of histoplasma. Commonly causes pulmonary infection
dirofilariasis normally has lesions in skin
35 year old with enlarged cervical lymph node.
CT shows necrotic lymph node.
Has fever and weight loss
What is the cause
Kikuchi's disease Toxoplasmosis Lymphma TB Sarcoidosis
Kikuchi’s disease is necrotising lymphadenopathy
Patient with non-painful erythema of his leg. No other focal symptoms Observations normal. No lymphadenopathy CRP10
What is most likely organisms associated with this?
Staph aureus Streptococcus pyogenes Yersinia enterocolitica Mycoplasma Pneumoniae Mycobacterium tuberculosis
Strep pyogenes
Not cellulitis - normal CRP, no other symptoms
It is erythema nodosum - panicullitis usually of anterior shins. Associated with infection, AI conditions, IBD, pregnancy, drugs.
commonly associated with strep throat
CF patient presents with worsening SOB.
What organism causes severe respiratory failure in CF patients
Pseudomonas aeruginosa Staphylococcus aureus Burkholderia cepacia Haemophilus influenzae Burkholderia pseudomallei
Pseudomonas aeurogina
Baby with sensorineural hearing loss.
Mother serology shows recent CMV infection.
Baby saliva CMV positive PCR.
What is reocmmendation?
Refer to paediatric infectious diseases on discharge IV gancilocivr for 2 weeks oral valganciclovir 6 weeks oral vanganciclovir 6 months CMV immunoglobulin
oral vanganciclovir 6 months
baby has confirmed cCMV, with evidence of disease
51 year old from Egypt presents with fever and vesicular rash that covers multiple dermatomes on his face, chest and abdomen.
Has fever. HIV neg
What is next management priority for this patient?
IV aciclovir oral aciclovir high-flow oxygen positive pressure isolation VZIG
oral aciclovir
likely disseminated varicella zoster
UK has temperate climate, so most people had chickenpox by adolescence. Egypt it is less common
IV aciclovir if respiratory or neurological symptoms
Which malignancy is EBV associated with?
AML Hodgkin's lymphoma ALL CML Non-Hogkin's lymphoma
Hodgkin’s lymphoma
results in latent B-lymphocyte infection, with potential for induction of lymphoblastoid cell lines capable of indefinite growth
Also linked to: nasopharyngeal carcinoma OHL Burkitt's lymphoma PTLD
ALL and T-cell lymphoma associated with HTLV
What diseases is HTLV associated with?
Spastic paraparesis
T-cell lymphoma
ALL
Patient with subacute encephalitis
Has myoclonus
What are possible causes?
Measles - SSPE
CJD
Whipples disease - if associated ataxia
Alzheimers
Huntington’s
Wilson’s disease
6 month old previously fit and well.
Up-to-date with immunisations
Sudden onset respiratory failure, with significant lymphocytosis
What is most likely cause
Bordetella pertussis Listeria monocytogenes CMV RSV Human metapneumovirus
Bordetella pertussis
30 year old keeps tropical fish presents with violaceous hand nodules, and swollen painful lymph nodes at her elbow.
What is the best way to culture a biopsy of the hand lesion to correctly diagnose this infection?
Culture on Lowenstein-Jensen at 30degC Culture on Lowenstein-Jensen at 37degC Culture on Sabouraud's agar at 30degC Culture on Sabouraud's agar at 37degC Culture on Sabouraud's agar at 42degC
Culture on Lowenstein-Jensen at 30degC
Possible diagnoses are M. marinum and nocardia
Mycobacterium marinum is most likely diagnosis
This likes to grow at 30degC, and not 37degC like Mycobacterium tuberculosis
M. marinum is photochromogenic, so change from cream colour to yellow in light
Sabouraud’s agar is primarily used for fungal pathogens and Nocardia
