18 - Community and Hospital Acquired Infections Flashcards
What is the definition of a notifiable disease?
A disease that by law should be reported to government authorities.
Allows PHE to monitor the disease and warn of early outbreaks
How is the severity of Pneumonia scored?
CURB65
Determines treatment!
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What antibiotics are given for community acquired pneumonia?
CURB 1: PO amoxicillin
CURB 2: PO amoxicillin + PO doxycycline OR IV amoxicillin + IV clarithromycin
CURB 3-5: IV co-amoxiclav + PO clarithromycin
What are some features of early and late meningitis?
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What are some causative organisms of meningitis?
Bacteria: N.Meningitidis, S.Pneumoniae, H.Influenzae, Listeria Monocytogenes, E.Coli
Virus: HSV, VZV, HIV, enterovirus
Fungi: cryptococcus
Cancer
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What investigations should be done if meningitis is suspected?
- Blood cultures before antibiotics
- LP within one hour (do CT head first if suspect shift of brain compartments)
- Throat swabs
- EDTA bloods for meningococcal PCR
- FBC, U+Es, glucose, LFT, Clotting, Lactate, HIV serology
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What should you record in a LP for suspected meningitis and what tests should you send off for?
- Opening pressure
- Appearance e.g bloody, pus, clear, cloudy
- Send blood serum for glucose at same time
- Tests: glucose, protein
How can you tell the difference between bacterial, viral and TB meningitis based on the CSF from LP:
- Appearance
- Predominant cells
- Cell count
- Glucose
- Protein
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Who and what prophylaxis should be given when a patient has meningitis?
Needs to be isolated for first 24 hours and give Ciprofloxacin to household members and anyone who has kissed patient’s mouth
How is bacterial meningitis managed?
- ISOLATE AND INFORM PUBLIC HEALTH
- Keep euvolemic, give oxygen, glycaemic control
Meningitic:
- Take blood cultures
- Perform LP within 1 hour if no signs of increased ICP
- IV abx (Ceftriaxone)
- Dexamethasone IV
Septicaemic:
- Same as above but leave LP unil stable and get ICU help
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What antibiotic therapy is given for meningitis:
- Younger than 60
- Older than 60
- Pregnant or Immunocompromised
- Younger than 60: IV Ceftriaxone. If allergic use Meropenem
- Older than 60: IV Ceftriaxone PLUS IV Amoxicillin to cover for listeria. If allergic use Meropenem
- Pregnant or Immunocompromsied: same as above
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How does the treatment for meningitis change if it is likely to be bacterial?
Add IV dexamethasone!!!!!!!
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What are some signs of increased ICP/brain shift in meningitis?
- Papilloedema
- Uncontrolled seizures
- Focal neurology
- GCS<12
NEED TO DO CT HEAD BEFORE LP!!!!!
What are some complications with delayed treatment of meningitis?
- Deafness
- Seizures
- Permanent neurological brain damage
- Shock
- Death
- Learning disabilities
How does encephalitis present?
Prodome of infection (raised temp, lymphadenopathy, cold sores, conjuncitivitis) then:
- Odd behaviour or confusion
- Focal neruology
- Headache
- Reduce GCS
- Seizures
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What are some of the causative organisms of encephalitis?
COXSAXIE MOST COMMON
Viral: HSV1/2, arboviruses, CMB, EBV, VZV, HIV, Measles, Mumps
Non-Viral: bacterial meningitis, TB, malaria, literia
What investigations should you do if you suspect encephalitis?
- Bloods: cultures, viral PCR, malaria film, glucose
- LP: send for gram stain, culture, protein, glucose, PCR for HSV/VSV/Enteroviruses/Adenoviruses
- Contrast enhanced CT: do before LP. Bilateral temporal lobe involvment is likely to be HSV
EEG: rule out status epilepticus
What is the treatment for encephalitis?
- Start aciclovir within 30 mins of arrival due to HSV
- Supportive therapy in HDU
- Symptomatic treatment e.g phenytoin for seizures
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How is C.Diff infection managed before antibiotics are given?
- Send stool sample for C.Difficile toxin ASAP
- Isolate patient
- Review drugs: stop ABX, PPIs, Steroids, Laxatives, Opioids, Loperamide
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What antibiotics are given for a C.Diff infection?
Vancomycin PO for 10 days
What are some markers of severe C.Diff infection?
- Temp>38.3
- Low albumin <25
- WBC rising >15
- Elevated creatinine
- Signs of severe colitis on endoscopy or radiologically
What empirical antibiotics are given for peritonitis/billiary sepsis?
Mild to Moderate (not severe sepsis or shock)
- Coamoxiclav IV
- Use meropenem IV if penicillin allergy
Admitted to ITU so severe:
- Piperacillin/Tazobactam IV
- Use meropenem IV if penicillin allergy
What antibiotics are given for the following parasitic causes of gastroenteritis:
- Cryptosporidiosis
- Giardiasis
Cryptosporidiosis: watery diarrhoea with no specific treatment, give supportive therapy, inform PHE
Giardiasis: PO metronidazole
What antibiotics should be given in an entamoeba histoloytica infection?
PO Metronidazole
If a patient has sepsis of unknown origin, what is the empirical antibiotic used?
IV Meropenem
If a patient has sepsis of unknown origin with hepatic cirrhosis, what is the empirical antibiotic used?
IV Co-Amoxiclav
(meropenem like normal sepsis pathway if penicillin allergic)
What investigations should be done for acute spontaneous bacterial peritonitis?
- Blood cultures x 2 from separate dsites
- Ascitic fluid x 2, one anaerobic, one aerobic
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What is the empirical antibiotics for SBP?
IV co-amoxiclav
(IV ciprofloxacin if penicillin allergy)
What prophylaxis is given in cirrhotic ascites to prevent SBP and what is the criteria to give this prophylaxis?
Oral Co-trimoxazole or Oral Ciprofloxacin
What antibiotics should you give for variceal bleeding in cirrhosis?
IV Co-amoxiclav
(IV ciprofloxacin if penicillin allergy)
What is the management for gastroenteritis due to bacterial and viral cause?
- Send stool for culture
- Manage fluids and electrolytes
- Isolate
- Avoid antimotility agents
- Supportive therapy (self limiting so no abx)
- Consider informing PHE if thing due to food source
What antibiotics are given for cystitis?
Women: Nitrofurantoin 3 days (or trimethoprim for 3 days if eGFR<45)
Pregnant Women or Complicated: Nitrofurantoin 7 days (or trimethoprim but only if not in first semester)
Men: Nitrofurantoin 7 days (or trimethoprim) and referral to urology
What antibiotics are given for pyelonephritis?
Women and Men
- Oral co-amoxiclav for 10 days (or ciprofloxacin)
- IV if too unwell
Pregnant Women
- Oral cefalexin (or ciprofloxacin)
- IV cefuroxime if too unwell
What antibiotics are given for cellulitis?
Mild moderate: Flucloxacillin PO (or Doxycycline PO if allergic)
Severe: Flucloxacillin IV 7 days (or Vancomycin IV if allergic)
What antibiotics are given for diabetic foot infection?
Mild: Flucloxacillin PO 14 days (or Doxycycline if allergic)
Moderate: Flucloxacillin PO PLUS Ciprofloxacin PO PLUS Metronidazole PO for 14 days
Severe: Piperacillin/Tazobactam IV PLUS Vancomycin IV
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How do you define the severity of a diabetic foot infection?
Mild: 2 signs of inflammation with cellulitis <2cm around the ulcer, infection limited to skin and superficial tissues, no systemic illness
Moderate: 2 signs of inflammation with cellulitis >2cm, spread beyond superficial fascia, involvement of muscle tendon, joint or bone
Severe: Foot infection with systemic toxicity (rigors, tachycardia, hypotension)
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What antibiotics are given for necrotising fascitis?
URGENT SURGICAL REFERRAL FOR DEBRIDEMENT!!!!!
Contact microbiology
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What are the antibiotics given for osteomyelitis?
If acutely unwell:
- IV flucloxacillin
(IV vancomycin if allergy) - Always consider MRSA
What antibiotics are given for spondlodiscitis?
Only given immediately if patient septic, otherwise consult with spinal surgeon:
- Flucloxacillin IV (Vancomycin IV if allergic)
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What is the pathophysiology of spondylodiscitis?
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What antibiotics are given in infective endocarditis?
Colloect three sets of blood cultures from separate sites!!!
4 weeks for native valves, 6 weeks for prosthetics!
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What antibiotics do not work on MRSA?
- Cephalosporins
- Penicillins
How is MRSA treated?
- Decolonisation: use nasal mupirocin and 2% chlorhexidine for 5 days
- Infection: oral vancomycin
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What is ESBL and how do you treat them?
Extended Spectrum Beta-Lactamases. Usually released by gram -ve bacteria like E.Coli and Klebsiella.
Resistant to all beta-lactams apart from Carbapenems so use broad spectrum Meropenem
How do you treat a line/catheter infection?
- Remove and replace infected line
- If fever take blood cultures
- If pus swab for cultures
- Flucloxacillin PO (or doxycycline) fo 5 days, 14 days if S.Aureus
What antibiotics are given for HAP?
Mild/Moderate: Co-amoxiclav PO (or doxycyline if allergic)
Severe: Co-amoxiclav IV (or meropenem if allergic)
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What antibiotics are given for a LRTI that is not pneumonia?
- Non purulent sputum: supportive measures
- Purulent sputum: amoxicillin PO (or doxycycline)
- Purulent sputum with severe disease: co-amoxiclav PO (or doxycycline)
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What are the different ways that infections are spread?
- Contiguous (direct spread)
- Haematogenous
- Inocculation
- Ingestion
- Inhalation
- Vector
- Vertical
- Sexual
What are the management principles of infections?
- Supportive
- Specific
- Infection control
What is the issue with S.Aureus when it infects heart valves?
It uses fibronectins to attach and forms a biofilm which is difficult for antibiotics to penetrate and is destructive
If S.Epidermidis is grown in a blood culture what is the most likely diagnosis?
Likely due to contamination from the skin!
What are some diseases that Group A Strep causes?
- Endocarditis
- GN
- Necrotising fascitis
- Pharyngitis
- Scarlet Fever
What are some risk factors for C.Diff infection?
- Abx use
- Older age
- Hospital stay
Risk of toxic megacolon and bowel perforation
What are CRO organisms?
Carbapenem resistant organisms