Infections Flashcards
How do we score sepsis risk?
SOFA
qSOFA – 2+ of hypotension, tachypnoea and Alt Mental Status
What is the sepsis 6?
Give - Abx, Fluid challenge & O2
Take - Serum lactate, blood culture & UO monitoring
What tests can be done for sepsis? (other than the sepsis 6)
FBC - infection U&E + C -- Renal failure CRP ABG -- Acidosis LFTs -- Liver damage Coag Screen & D-dimer -- DIC Glc -- Hyperglycaemia
What are the characteristics of SIRS?
High or low temp
Tachycardia
Tachypnoea or low PaCO2
Leukocytosis/Leukopenia
How do you detect parasites in gastroenteritis & treat them?
Stool microscopy
Duodenal Biopsy
Treat with Metronidazole
What form’s of gastroenteritis can cause HUS or seizures?
Salmonella can cause both
Enterohaemorhagic E.Coli often causes HUS –> renal failure & Anaemia
What causes traveller’s diarrhoea?
Enterotoxigenic E.coli
Shigella
Campylobacter
What viruses cause gastroenteritis and how do you detect them?
Rotavirus
Noravirus
Serum PCR or Stool Antigen tests
What causes food poisoning?
Staph Aureus Toxin Bacillus Cereus (Reheated rice) Clostridium Perfringens (Undercooked meat)
What’s in Oral Rehydration Salts?
Glc
Amino acids
NaCl
How would you check for Infective endocarditis in a patient with PUO?
Look for a new murmur
If found do a TOE
How o you test for TB?
Mantoux test
Sputum sample for ZN stain & culture
Bone marrow biopsy
What do you do if you have a pyrexia of unknown origin and can’t find the cause?
Therapeutic Trial:
1) Anti-TB medication, response within 2 wks
2) Steroids, dramatic response within 48hrs
Pyrexia of Unknown Origin along with haematuria, what do you do?
- Renal US for cancer
- Renal biopsy & Auto-Abs for Polyarteritis
What type of HIV causes the epidemic?
Type 1 HIV Group M
What cells does HIV target?
CD4+ cells e.g. macrophages, Th cells, monocytes, brian & skin
What are the drugs involved in cART for HIV?
- Nucleoside Transcriptase Inhibitors
- Non-nucleoside Transcriptase Inhibitors
- Integrase Inhibitors
- Protease Inhibitors
cART is 3 drugs from atleast 2 classes in 1 pill
What does an acute HIV infection look like?
Mostly asymptomatic
Some get seroconversion illness:
- Looks like glandular fever
- But EBV -ve
What conditions suggest an HIV test?
- Thrush
- Unexplained wt loss or lymphadenopathy
- Guillain Barre
- Dementia
- Aspergillosis
- Anal or lung cancer
What conditions define AIDS?
- PML
- Kaposi’s Sarcoma
- Cervical Cancer
- CMV retinitis
- Pneumocytis Pneumonia
- TB
- NHL
- Cryptococcal Meningitis
- Cryptosporidiosis
How do you test for HIV?
Serum/Salivary ELISA for Abs & antigens
Babies need Viral Genome Detection (as they have the mum’s antibodies regardless of inf)
What are the common HAIs and how do you get them?
C.diff & Salmonella by Faecal-oral transmission
Staph Aureus by Direct transmission
TB & Neisseria Meningitidis by Droplet transmission
Group A strep & Viruses by penetrating injury
What methods do you have for sterilization?
- Gas (Ethylene Dioxide)
- Autoclave
- Hot Air Oven
- Ionising Radiation
How might C.Diff present?
- Pyrexia
- Diarrhoea
- Characteristic Smell
- Abdo Pain
- Leukocytosis
- pseudomembranous colitis
What causes Rabies and how does it present?
Lyssavirus
Non-specific symptoms, mania, hydrophobia, increased saliva/tears & decreased ability to swallow
They die of resp failure
How do you test for an treat Rabies?
PCR
PEP (Human Rabies Immunoglobulin & rabies vaccine)
How does Lyme’s disease present
Early - Erythema Migrans
Late:
- Acrodermatitis Chronica Atrophicans
- Neuroborrelliosis
- Arthritis
- Lymphocytoma
- Perimyocarditis or heart block
How do we detect and treat lyme’s disease?
ELISA serology & immunoblot test
Oral Doxycycline
What causes Leptospirosis?
L. Icterohaemorrhagica (rats)
L. Hardjo (cattle)
Mostly got through contaminated water
How does leptospirosis present?
Flu like illness
Can develop Weil’s Disease:
- AKI
- Jaundice
- Bleeding
How do you detect and treat leptospirosis?
ELISA Serology
PCR
Culture
Doxycycline
IV penicillin if severe
Dialysis if AKI
Mechanical Ventilation if needed
Where do you get brucellosis?
Cattle & Dairy
How does brucellosis present and how do we treat it?
Non-specific symptoms incl drenching sweats & a high undulant, resistant fever
Can develop joint pain
Arthritis, endocarditis & Epididymo-orchitis
Doxycycline for 2-3months + 1wk of rifampicin or gentamicin
CNS manifestations? –> Add Co-trimoxazole
what are the symptoms of influenza?
Abrupt high fever >3days + 2 of:
- Sorethroat or rhianorrhoea- Myalgia
- Cough
- Malaise
- Headache
Complications of influenza?
Acute Bronchitis
secondary bacterial pneumonia
Also Guillain Barre, Myocarditis, Viral pneumonia & exacerbating underlying illness
When would you treat Influenza and why?
If complicated or very sick give:
Neuraminidase inhibitors i.e. Oral Oseltamavir or Inhaled Zanamivir
How is flu transmitted?
Droplet
Direct
Indirect on surfaces
Birds
What are the surface antigen of influenza virus
N - Neuraminidase - allows virus to break out of host cell
H - Haemaglutinin - enters host cells
How does the influenza virus change?
Antigenic drift - Small molecular changes year on year
Antigenic Shift - Sudden combining of 2 strains –> epidemics
How do we test for influenza?
- Viral swab for PCR & Molecular detection
- CXR (rule out pneumonia)
- Blood culture (for other infections)- Pulse oximetry & resp rate for monitoring
- U&Es, FBC & CRP
What are the major types of Aspergillus infection?
- Acute Invasive Aspergillosis
- Allergic Bronchopulmonary Aspergillosis
- Chronic Pulmonary Aspergillosis
- Pulmonary Aspergilloma
- Influenza Ass Aspergillosis
How do we test for aspergillosis?
CT chest, PCR & bronchoalveolar lavage if a neutropenic patient
Otherwise if you suspect it you can do Sputum culture and aspergillus specific IgE/G
How do you treat aspergillosis
Voriconazole
Isavuconazole
How do we test for and treat candida?
Blood culture & PCR
Echinocandin & fluconazole
How does cryptococcus present?
LRT infection with constitutional symptoms
Moves to brain causing headache, confusion, AMS, visual problems & Coma
Typically HIV associated
How do you test for and treat Cryptococcus?
Blood Culture & Antigen testing
LP for culture, antigen testing & india ink
Amphotericin B & flucytosine (induction) & Fluconazole (maintenance)
How do you treat Malaria?
Falciparum –> Riamet (Artemether & Lumafantrine)
Complicated –> IV artesunate
Non-falciparum –> Chloroquine
Vivax or Ovale –> Add Primaquine
Complications of Malaria?
Algrid Malaria Anamia Jaundice Blackwater Fever Pulm Oedema Cerrbal Malaria DIC Hypoglycaemic Acidosis
How do you test for malaria and its complications?
Rapid Antigen Test
Thick & Thin blood films
QBC
FBC, U&Es + creatinine, LFTs & urinalysis ABG & Lactace (for acidosis) Glc (Hypoglycaemia) Clotting screen Blood culture (concominant sepsis)
How do we treat hair infections and what causes them?
Topical Abx
Oral Abx
Surgery
Staph Aureus and sometimes Strep Pyogenes
What toxins cause Toxic Shock Syndrome & SSSS?
TSS = TSST1 SSSS = Toxin A or B
Both from Staph Aureus
What causes Necrotizing Fasciitis and what are the risk factors?
Type 1 - Mixed inf – Staph, Strep, Clostridium, enterococci & Gram -ve bacilli
Type 2 - Strep Pyogenes
IVDA DM PVD Surgery Trauma
How does Necrotizing Fasciitis present and how do we treat it?
Rapid swelling, redness, pain & decreased sensation
Haemorrhagic bullae, necrosis & Crepitus
Systemic Sx e.g. fever malaise etc
Supportive
Surgery
Broad Spec Abx (Clindamycin, Gentamicin & Flucloxacillin)
How do you treat TSS?
GEt a blood culture & isolate the toxin
Remove the causative agent (e.g. tampon) Fluids Inotropes Abx \+/- IV immunoglobulins
What causes pyomyositis, how does it present and what are the risk factors?
Staph Aureus
Fever, Muscle pain & Woody stiffness
Immunocompromise (by any means) & Rheumatological disease are RFs
How do you test for and treat pyomyositis?
Blood culture
CT or MRI to isolate muscle loss & abscess
IV Abx & Drainage of abscess
What are the risk factors for surgical site infections and what causes them?
.DM Smoking Obese Malnutrtion Steroids
Staph Aureus
Pseudomonas
E Coli
What causes IV catheter infections and what’s the big risk should someone get one?
Staph Aureus
Endocarditis, so do an echo
What causes Infectious Tenosynovitis and how would it present?
.Staph Aureus –> Strep –> Mycobacterium or fungi if chronic
Semiflexed fingers
Swollen finger
Tender tendon
Pain on extension
What are the risk factors for septic bursitis, how do you test for and treat it?
IVDA Immunocompromise DM Renal Disease Rheamtic disease Alcoholism
How does typhoid present?
Early you get a high fever, malaise, neutrophilia, bradycardia, headache, constipation & cough
Wk2 develops into peaked fever, rose spots, diarrhoea, abdo pain, tachycardia & neutropenia
Late presentations include intestinal bleeds, perforations, peritonitis & metastatic inf
What causes typhoid, how do you test for it and how do you treat it?
Salmonella Typhi
Blood, marrow, urine & stool cultures
FBC & LFTs
Supportive care
Oral Azithromycin or IV Ceftriaxone if severe
How is typhoid transmitted?
Faecal oral route
How is dengue fever transmitted?
Aedes Aegyptii Mosquitos
How does dengue fever present?
Abrupt fever & Maculopapular Rash
+/- headache, arthralgia, myalgia, petichiae & purpura
How do you diagnose and treat Dengue fever?
PCR & Serology
Clinical diagnose can be made with:
- +ve tourniquet test
- Leukopenia
- thrombocytopenia
- Elevated Transaminases
Treat with supportive fluids, FFP & Platelets
Prevent with Dengvaxia Vaccine
What spreads Schistosomiasis?
Fresh water (snails) spread Schistosoma Haematobium (Africa) and Japonicum (japan)
How does Schistosomiasis present
Early - Swimer’s itch
Wks – Katayama Syndrome (Fever, urticaria, lymphadenpathy, diarrhoea, abdo pain, cough & hepatosplenomegaly)
1-2months – Cystitis causing haematuria or dysentery +/- portal hypertension
How do you test for and treat Schistosomiasis?
Stool & Urine Microscopy for Ova
Rectal Biopsy
Antibody Tests
Praziquantel +/- prednisalone if severe
what cause typhus & how does it present?
Rickettsia Conorii or Africae
Spread by ticks
Abrupt fever, headache, confusion, jaundice & rash (+/- bleeds/thrombosis)
How do we test for and treat typhus?
Serology & PCR (can also do FBC, LFT CRP & U&Es)
Tetracycline
What are the viral hemorrhagic fevers and how do they present?
Ebola & Lassa Fever
Abrupt High fever, myalgia & conjunctivitis plus other non-specific signs e.g. headache, prostration, pleuritic pain and malaise
How would you manage viral haemorrhagic fevers?
High security inf unit and supportive therapy
What spread Zika virus?
Aedes Mosquitos
Sex
Transfusion
How would you tell fungal vs bacterial vs viral meningitis?
Fungal pretty much only comes along with HIV
Bacterial vs viral on LP:
- Bacterial = High protein / Low Glucose / High pressure / Neutrophilia
- Viral = Low protein / Normal glucose / Normal Pressure / Lymphocytosis
What cause fungal meningitis?
Cryptococccus
What causes bacterial meningitis?
Neonates - E coli or
Kids - Haemophilus Influenzae
Adults - Strep Pneumoniae or N Meningitidis
How do you treat bacterial meningitis?
Neonates (Ecoli or ) & kids (H Influenzae) – Cefotaxime
Adults (Strep Pneumoniae or N Meningitidis) – Ceftriaxone
What viruses cause Meningitis?
HSV
Enteroviruses (Coxsackie, Echovirus etc)
How do you treat viral meningitis?
Aciclovir
