Week 5 Miscellaneous Infections Flashcards
What are the 3 main Clostridium spp of importance? (IMPT)
- C. perfringens
- C. tetani
- C. botulinum
What are the clinical presentations of Tetanus and how is it acquired? (IMPT)
- By Clostridium tetani
- Found in animal feces & contaminated soil (so can be acquired through splinters, cuts etc)
Presentation (toxin causes sustained excitation of motor neurons to cause sustained motor contraction)
- Stiffness
- Lockjaw
- Sardonic/sneering grin
- Opisthotonos (extreme arching of back)
What are the clinical presentations of Botulism and how is it acquired? (IMPT)
- By Clostridium botulinum
- Acquired by food poisoning (from preserved food)
Presentation (botulinum toxin in GI tract binds irreversibly to presynaptic nerve endings to inhibit ACH release)
- First affects eyes (double vision, drooping eyelids)
- Flaccid paralysis
- Speech and swallowing difficulty
- Breathing difficulty
- Death from cardiac or respiratory failure
Where is meliodosis endemic to and what are the clinical presentations?
- By Burkholderia pseudomallei
- Gram negative bacillus
- Near the equator/tropical regions during monsoon rainy seasons
- Present in soil and water
- Often latent but may reactivate
- Abscesses on lungs/organs
- May also be asymptomatic
What are the causes of Listeriosis and s/s?
- Listeria monocytogenes
- Gram positive bacillus
- Through contaminated food, unpasteurised dairy products, uncooked food
s/s:
- Fever
- GE
- May be asymptomatic
- Septicemia or meningitis in immunocompromised px
How can anthrax be acquired?
- Bacillus anthraxis
- Found naturally in the soil and spores can infect animals or animal products
- Inhalation
~ Of spores when handling contaminated materials - Cutaneous
~ When spores get into cuts on skin - GI
~ When eating undercooked meat from infected animals
How is leptospirosis transmitted and what are the s/s and their phases?
- By Leptospira interrogans
- Spread through contact with urine of infected animals (esp rats) in water or soil
- s/s:
~ Jaundice
~ Red eyes
~ Fever
~ Rigors
~ Vomiting
~ Myalgia (muscle pain)
~ Diarrhea
~ Rash
Phases:
- Usually self-limiting (first phase) but
- Re-infection is more severe
~ May have hepatorenal failure, meningitis, bleeding or haemoptysis
~ Lasts >3weeks
- Treated with penicillin
What is toxoplasmosis and what are the serious implications? (IMPT)
- By Toxoplasma gondii parasite
- Transmitted through undercooked meat or food contaminated by cat feces, mother to fetus or blood transfusion
Implications:
- Usually asymptomatic/mild (flu-like symptoms or ocular issues) unless in pregnant or immunocompromised px
- Severe reactivation and seizures
How is malaria transmitted?
- Plasmodium parasites (eg P falsiparum, knowlesi, vivax, ovale, malariae)
- Through female Anopheles mosquito
What are the symptoms of malaria?
Uncomplicated malaria
- Cold -> hot (fever, vomiting, seizures) -> sweating stage
- Fever, chills, sweats
- Headache, myalgia, malaise
- N&V
- Splenomegaly
- Mild jaundice
- Hepatomegaly
Severe malaria (when complicated by organ failure or abnormalities in blood)
- Cerebral malaria (changes in consciousness)
- Severe anemia and haemoglobinuria (due to haemlolysis)
- Acute respiratory distress syndrome (ARDS)
- Blood coagulopathy
- Hypotension
- AKF
- Hyperparasitemia (>5% of RBC infected by parasites)
How is malaria diagnosed? (IMPT)
- Microscopy using thick and thin films
~ 3 sets of blood films taken every 12-24 hours, all 3 must be negative - Rapid diagnostic test
~ But may not detect low level of parasitemia
What are the 3 Chlamydia bacteria of significance? (IMPT)
- Chlamydia trachomatis (STD)
- Chlamydia pneumoniae (pneumonia)
- Chlamydophila psittaci
What are the 2 major groups of helminths/parasitic worms?
Nematodes/roundworms:
- Intestinal and tissue roundworms
Platyhelminths/flatworms:
- Trematodes/flukes
- Cestodes/tapeworms
How to diagnose intestinal roundworms? (IMPT)
- Occult blood test (OCP)
- Stool microscopy
How are tapeworms transmitted?
- Consumption of infected animal (eg cow, pig)
