Infectious diseases and micro Flashcards
Bacterial causes of pneumonia
- Strep pneumonia
- H. influenza
- Staph aureus
Atypicals:
- Legionella (stagnant warm water)
- Mycoplasma pneumoniae
- Chlamydia pneumonia
fungal causes of penumpnia
- histoplasmosis
- cryptococcus
- pneumocystis jiroveci (pneumocystis pneumnoia)
- aspergillosis
viral causes of pneumonia
- influenza
- SARS
- RSV
signs of pneumonia O/E
- dull percussion
- increased tactile vocal fremitus
- bronchial breath sounds
- late inspiratory crackles
what is the CURB65
pneumonia mortality risk
- Confusion (abbreviated mental test <=8 or new
- Urea >7mmol/L
- Raised RR >=30
- BP <90 S or <60 D
- Age >=65
1 point- OP tx
2 points- IP tx or OP with close f/u
>3 points- IP tx with ITU admission
ix pneumonia
- CRP !!!!- procalcitonin - sputum culture/lavage - bloods culture - CXR- veil like opacity, +-lobar
Tx peumonia
CAP
- low severity- PO amoxicillin, doxy, clarithro, erythro
- severe- PO or IV- coamox with clarithro if atypical or PO erythro
HAP
- coamox PO or doxy, cefalexin
- severe- IV Taz
- add vanc/teic/linezolid if ?MRSA
- pain meds
- CPAP
what organism causes epiglottitis
- Haemophilus influenza B
tx epiglottitis
- keep child calm, do not lie them down
- intubate under GA, THEN take bloods, cultures
- rigid laryngoscopy
- IV cefotaxime, chloramphenicol if allergy hx
- rifampicin to household
what organism tends to cause respiratory infections in CF patients
- peusdomonas aeruginosa (adults)
- S aureus (most common in children)
- HiB
what organisms most commonly cause flu
- influenza A, B, C
- A and B= seasonal flu
- A- pandemics
- C- mild illness, no vaccine
drug tx flu
antiviral eg oseltamivir PO or canamivir inhaled if any of the following apply:
- -> national surveillance indicated flu is circulating
- -> person is in ‘at risk’ group
- -> person can start tx within 48hours of sx onset (off-label use outside of this duration, use clinical judgement)
- -> person is not in at risk group but felt they may develop complications
what is considered an ‘at risk’ group of flu
- splenic dysfunction
- sickle cell
- coeliac
- chronic resp disease
- chronic heart, liver or kidney disease
- neuro disease
- diabetes
- immunosupression (HIV, CT)
advice to give someone with flu
- oral fluids
- paracetemol, NSAID
- bed rest
- fever, GI sx should start to resolve within 1w
- fatigue, cough may last longer (2w)
- safety net for hospital- confusion, no urine, persistent D+V, SOB, pleuritic chest pain, cough up blood
- arrange f/u if no improvement in 1w
- lower threshold for admission/visit to hosp if child/baby
causes of UTI/pyelonephritis
- E.coli (most) !!!- staph saprophyticus (young women) - proteus - Kelbsiella - enterococcus faecalis !!- yeast
what organisms cause UTI with catheter
- E.coli
- candida
- pseudomonas
- enterococcus
- staph aureus
- coag -ve staph (S.epidermis, S capitis, S.haemolyticus
causes of UTIs in children
- E.coli
- proteus (more common in boys)
- pseudomonas (indicates structural abnormality
abx to tx UTIs
- non pregnant women, men, children
1. nitrofurantoin, trimethoprim
2. amox, or if a man, consider prostatis/pyelonephritis if no improvement witin 48hours of 1st line - pregnant women
1. nitro
2. amox, cefalexin - asx- amox, cefalexin, nitro
tx recurrent UTIs
one dose after trigger/post coital, or once nightly
- nitro, or trimeth
- amox or cefalexin
- review every 6months
- suggest vaginal oestrogen in post meno women
tx UTIs with catheter
nitro/trimeth
if with upper UTI- cefalexin
IV- ceftriaxone, amikacin
Pregnant
1- cefalexin
IV cefuroxime
Children
1. cefalexin
IV- ceftriaxone, amikacin
tx pyelonephritis
Adults and children:
PO- cefalexin
IV- amikacin, ceftriaxone
pregnant-
cefalexine PO,
IV cefuroxime
sx acute prostatitis
- UTI- LUTS
- weak stream
- acute retention
- lower back pain
- perineal, penile or rectal pain
- pain on ejaculation
sx chronic prostatitis
- complication of acute
- at least 3m of urogenital pain
- with LUTS
ix ?prostatitis
- MSU (shows UTI)
- blood cultutres, FBC
- abdo examination- distended bladder, costovertebral angle tenderness
- DRE- GENTLY– do not massage or collect secretions for culture as you risk causing sepsis. Will feel warm, large and boggy
management of prostatits
ABX
- PO cipro, levofloxacin
- IV amikacin, ceftriaxone
PAIN
- paracetemol +- low ose weak opioid, NSAID
ADVICE
- fluids
- usual course= several weeks
- safety net- worsening sx, sx dont improve within 48hour of starting abx, very feverish, confusion
ADMIT
- admit if severe, sepsis/retention/abscess sx, no improvement within 48hours of abx
- urgent referral if immunocomprimised, pre-existing urological conditions eg BPH, indwelling catheter, STI is identified
F/U
- arrange f/u in 48hours to check on progress, review abx with culture results
- reveiw abx after 14d- to continue?
- refer to r/o structural abnormalities of the UT
management of sepsis
BUFALO 6
Inform seniors/get help
- ask someone to catheterise
- O2
- IV access- chultures, X match, clotting, FBC, UE, LFT, VBG
- fluids- 500ml bolus NaCl 0.9%
- IV abx
- UO- make sure it’s completed
abx used in sepsis
depends to local protocols, but generally:
ADULTS
Community acquired:
- Tazocin (allergy-cefuroxime)
- add vanc or teic or 2-linezolid if ?MRSA
- anaerobic- add metro to broad spec cephalo eg cefuroxime
- if resisatnt- meropenem
CHILDREN( 1m-18yrs)- comm acquired - aminoglycoside (gent, amikacin, streptomycin) plus amox/ampicillin - or cefotaxime/ceftriaxone alone
ALL PEEPS:
Hospital acquired
- IV taz or meropenem
- add vanc or teic or 2. linezolid if ?MRSA- anaerobic- add metro to broad spec cephalo eg cefuroxime
tx sepsis ?related to vasc catheter
vanc or teic
tx meningococcal sepsis
- benzylpen or cefotaxime for 7d
- chloramphenicol in pen allergy
Meningitis:
3m-50years
- cefotaxime or chloramphenicol or ceftriaxone 2-4g IV
- note- dont give ceftriaxone in <3m as may lead to hyperbilirubinaemia and risks Kernicterus
- add amox IV if >50y/<3m to cover for listeria
- dexamethasone
- IV aciclovir if ?viral
Contacts:
- ciprofloxacin, (rifampicin or ceftriaxone)
what counts as low urine output
1ml/kg/hour is normal
<0.5ml/kg/hour is low
anuria is <100mls in 24hours
Management of pt with low UO
A-E
- high flow O2
- bloods- FBC, UE, clotting, gas
- BP
- fluid challende- 250-500ml boluses
- aim for S >100mmHg
- anuric- consider obstruction (post-renal)– check catheter, bladder washout using 50mls normal saline
- check drug chart- no renal damaging drugs (ACEI, NSAIDs, abx)
- AKI–> furosemide
definition and sx of AKI
- oliguria <0.5mls/kg/hour for >6 hours or anuria
- rise in Cr >26micromol/L in 48hours/50% rise in 7 days
- JVP raised
- chest auscultation- basal crackles
- ankle oedema
what organism causes meningococcal sepsis, histological appearance
- Neisseria meningitidis
- gram negative (pink)
- diplocccus
- intracellular
- coffee bean shaped
histological appearance of strep pneumonia
- lancet shaped
- (diplo)cocci
- gram positive (purple)
histological appearance of E.coli
- rod shaped/bacilli
- anaerobe
- gram negative (pink)
what is trichomonas vaginalis
- spread through sexual contact
- protozoan , single cells
- flagella
sx trichomonas vaginalis
- 50% no sx
- frothy, yellow/green discharge
- fishy odour
- itching
- dysuria
- dyspareunia
- balanitis
signs trichomonas vaginalis
- strawberry cervic (colpitis macularis
- vaginal Ph raised (>4.5)
ix ?trich
- F- charcoal swab with microscopy (posterior fornix or self taken)
- M- urethral swab or first catch urine
tx trich
- GUM referral
- metronidazole
what is a tapeworm, where is it caught from
- cestoda class worm
- long worm
- raw/undercooked meat, contaminated water
life cycle of a tape worm
- eggs passed in faces from host
- ingested by intermediate host
- hatch
- larvae enter tissues of internmediate host
- encyst
- cysts ingested by human host
sx tapeworm
- mostly no sx
- passage of worm (proglottids)
!!!!- itching - vague GI sx- abdo pain, cramps, D+N, wt loss, malaise
!!!!!- worm absorbs lots of B12- pernicious anaemia (paraesthesia, balance, confusion - hydatid cyst- liver, lungs
sx hydatid cyst in liver
- epigastric pain
- dyspepsia
- obstructive jaundice, pruritis (obstructs bile duct)
tx tapeworm
- praziquantel
- niclosamide
- neuro sx- albendazole
- cyst aspiration
- surgery
what is pinworm
- small slender worms with pointed tail
- reside in caecum, appendix, ascending colon
- enterobius vermicularia
- primarily paediatric
- transmitted via contact- bedblothes, bedding, towels, toilets, doorknobs, sex
sx pinworm
- asx
- intense itching, prickling pain in anal area/vaginal
- worse at night
- abdo discomfort, loss of appetite rarely
ix pinworm
- glass slide microscopy by dabbing stretched anal folds with cellophane tape in the early morning :)
tx pinworm
- mebendazole, albendazole- 2 doses 2w apart
- tx household and class at same time
- wash sheets, clothing
- strict handwashing and cleaning after appt
what is schistosomiasis (bilharzia)
- parasitic worm
- contact with fresh water and snails–> transmission
sx schistosomiasis
Acute:
- maculopapular lesions
- itchy
- diarrhoea, cough
- abdo pain
- malaise, arthralgia
Chronic:
- bowel wall egg deposition- blood diarrhoea, cramping, perf, appednicitis
- portal tracts- splenomegaly, ascites
- UT- haematuria, dysuria, sq cell carcinoma
- CNS sx
- postcoital bleeding, ulceration, irreg menstruation
ix ?schistosomiasis
- microscopic examination for ova in stool/urine samples
- antiodies/antigens in blood or urine
tx schistosomiasis
- corticosteroids
- praziquantel
what is legionnaries disease
severe form of penumonia caused by legionella pneumophila
- found in warm stagnant water and fresh water
- cannot spread person to person
sx legionnaires disease
cough is dry
pneumonia sx plus systemic infective sx:
headaches, muscle pain, chills fever fatigue cough, dyspnoea, chest pain N+V, diarrhoea chest pain
tx legionnaries disease
- notifiable disease
- fluroquinolones- levofloxacine, cipro
- macrolides- azithromycin, clarithro, erythro
microscopic appearance of legionela
gram negative (pink)
rod/bacillus
aerobic
non spore forming
what causes mumps
- paramyxovirus
- RNA virus of the rubulavirus family
complications of mumps
- **- pancreatitis (abdo pain)
- orchitis and redcued fertility
- meningitis, encephalitis
- **- sensorineural hearing loss
ix for ?mumps
- PCR testing of saliva swab
- blood/saliva antibody testing
transmission of mumps
- droplets of saliva
- kissing, sneezing, coughing
what causes pertussis
ie whopping cough
- bordetella pertussis- gram negative
ix for pertussis
- nasopharyngeal or nasal swab —> PCR or bacterial culture
- if cough present >2w- antipertussis toxin immunoglobulin G (oral fluid or blood)
management of pertussis
- notify UKHSA
- supportive
- avoid contact with vulnerable people
- macrolides– azithromycin, ertyrho, clarithro
- co-trimoxazole
- should resolve within 2m
what causes yellow fever
- virus in genus flavivirus
locations where yellow fever is high
South america, sub-saharan africa
- nigeria
- brazil
vector of yellow fever
mosquito
sx yellow fever
- fevere, photophobia, headaches
Acute phase
- vomiting, fever
!!!- headache, rigors, myalgia
- anorexia
toxic phase- occurs in next few days in 15% or people, half of whom die from shock
- fever
!!!- jaundice
- haemorrhage (mouth, eyes, stomach)
!!!- DIC
!!!- renal function deterioration (prerenal or gomerulonephritis and intersitial nephritis)–> oedema
- hypothermia
what is haemolytic uraemic syndrome
- due to E.coli shiga toxins, also produced by shigella
- antimotility meds eg loperamide during infection of these pathogens increases the risk
- thrombosis within small BVs
- platelets consumption
- thrombotic microangiopathy
- high bleed risk
sx HUS
- haemolytic anaemia
- thrombocytopania
- AKI
AKI
- reduced UO
- haematuria, dark brown
- lethargy, confusion
- vomiting
- oedema
- HTN
THROMBO
- bloody diarrhoea
- abdo pain
- bruising
- fever, rigors, headache
- note: jaundice is rare
- often children <5yo
ix ?HUS
- FBC, clotting, LFTs, UE
- peripheral blood smear show signs of RBC injury/haemolysis- schistocytes, RBC fragments
- stool culture- shiga toxin
- urinalysis
tx of HUS
- supportive
- dialysis
- anti HTN
- fluid balance
- blood
- renal transplant
- avoid abx, antimotility agents, NSAIDs
name some aminoglycosides
gentamicin
streptomycin
name some cephalosporins
‘cef-‘
name some penicillins
‘-cillin’
name some tetracyclines
-cycline
tetracycline
doxycycline
name come (fluoro)quinolones
-floxacin
ciprofloxacin
levofloxacin
ofloxacin
name some macrolides
- mycin
erythromycin
clarithromycin
azithro
name some sulphonamides
sulfalazine
sulphmethoxazole
sulfadiazine
names some glycopeptides
vancomycin
what is augmentin
co-amoxicillin
what are some important things to consider when px aminoglycosides
gent, streptomycin
!!!!- must be taken IV
!!!!!- usage should not exceed 7 days where possible
- nephrotoxic
- weight dosed and monitored using normogram
SE of aminoglycosides
- ototoxicity
- aphonia
- GI upset
- nephrotoxicity
- skin reactions
what are some things to consider when using carbapenems
eg meropenem
- beta lactam ring in structure- be careful in those with penicillin allergy
- imipenem is broken down by enzyme in the kidney, so is given with cilastatin (enzyme inhibitor), to block this renal metab
- v broad spec- often used in sepsis and severe/resistant infections
SE carbapenems
- GI
- *- skin reactions
- *- seizure inducing (rare)
- pancytopenia
things to consider when givign cephalosporins
- do NOT give in pen allergic patients
- **- accumulate in renal impairment as are excrete renally
- may cause c.diff
- ***- may cause false positives on coombs test
things to consider when giving glycopeptides
- used in MRSA clearance
- vanc should not be given PO as will not be absorbed (give IV)
- vanc needs plasma conc monitoring
- dont infuse too quickly
glycopeptide SEs
- otoxicity
- nephrotoxicity
- skin reactions
- red man syndrome if given too quickly