Diseases of Nervous System and Eyes Flashcards
Bacterial Meningitis
Major Symptoms
Sudden high fever and severe meningeal inflammation
Bacterial Meningitis Causative Organsism(s) x5
Neisseria meningitidis Streptococcus pneumoniae Haemophilus influenzae b Listeria monocytogenes Streptococcus agalactiae
Bacterial Meningitis
Neisseria meningitidis
Type of Pathogen
Bacteria (Gram -)
Bacterial Meningitis
Neisseria meningitidis
Mode of Transmission
Respiratory droplets
Bacterial Meningitis
Neisseria meningitidis
Key Associations
N. meningitidis known as the “meningococcus” purple spotted rash; Most common cause of meningitis in those <20 (collegee students in dorms 23x more likely)
Bacterial Meningitis
Streptococcus pneumoniae
Type of Pathogen
Bacteria (Gram +)
Bacterial Meningitis
Streptococcus pneumoniae
Mode of Transmission
Respiratory droplets
Bacterial Meningitis
Streptococcus pneumoniae
Key Associations
known as the “pneumococcus”; most common bacterial meningitis in adults
Bacterial Meningitis
Haemophilus influenzae b
Type of Pathogen
Bacteria (Gram -)
Bacterial Meningitis
Haemophilus influenzae b
Mode of Transmission
Respiratory droplets
Bacterial Meningitis
Haemophilus influenzae b
Key Associations
Commonly causes meningitis in children <18 months)
Bacterial Meningitis
Listeria monocytogenes
Type of Pathogen
Bacteria (Gram +)
Bacterial Meningitis
Listeria monocytogenes
Mode of Transmission
Contaminated food and drink
Bacterial Meningitis
Listeria monocytogenes
Key Associations
elderly, babies, pregnant women
Bacterial Meningitis
Streptococcus agalactiae
Type of Pathogen
Bacteria (Gram +)
Bacterial Meningitis
Streptococcus agalactiae
Mode of Transmission
At birth via passage through birth canal or by health care personnel
Bacterial Meningitis
Streptococcus agalactiae
Key Associations
Meningitis in premature babies and infants < 3 months
Hansen’s Disease
AKA
Leprosy
Hansen’s Disease (Leprosy)
Major Symptoms
- Tuberculoid leprosy: nonprogressive*, regions of lost sensation as a result of nerve damage;
- Lepromatous leprosy: progressive*, gradual loss of facial features, digits, other body structures
Hansen’s Disease (Leprosy)
Causative Organism
Mycobacterium leprae
Hansen’s Disease (Leprosy)
Type of Pathogen
Bacteria (acid-fast)
Hansen’s Disease (Leprosy)
Mode of Transmission
Person-to-person contact or break in the skin; can also be acquired from handling or consuming armadillos
Hansen’s Disease (Leprosy)
Key Associations
Strong immune system = tuberculoid leprosy;
Weaker immune system = lepromatous leprosy;
death is rare
Botulism
Major Symptoms
Intoxication; flaccid paralysis; Death can result from asphyxiation- cannot inhale
Botulism
Causative Organism
Clostridium botulinum
Botulism
Type of Pathogen
Bacteria (Gram +)
Botulism
Mode of Transmission
Contaminated food (esp home-canned); honey (infants); endospores enter wounds
Botulism
Key Associations
Extremely potent; Infant botulism most common form in US; “floppy baby syndrome”; Category A Bio-terrorist threat
Tetanus
AKA
Lockjaw
Tetanus (Lockjaw)
Major Symptoms
Characteristic severe muscular contraction; lockjaw; sweating, drooling, grouchiness, constant back spasms; death from asphyxiation- cannot exhale
Tetanus (Lockjaw)
Causative Organism
Clostridium tetani
Tetanus (Lockjaw)
Type of Pathogen
Bacteria (Gram +)
Tetanus (Lockjaw)
Mode of Transmission
Break in skin, mucus membranes; puncture wounds; umbilical stump
Tetanus (Lockjaw)
Key Associations
- Risus sardonicus* = smiling spasm
* Neonatal tetanus* mortality > 90% – infected umbilical stump
Viral meningitis
AKA
Aseptic meningitis
Viral meningitis (aseptic meningitis) Major Symptoms
Similar to bacterial meningitis, but milder
Viral meningitis (aseptic meningitis) Causative Organism
Enteroviruses: Poliovirus, Coxsackie virus, Echovirus (90%)
Viral meningitis (aseptic meningitis) Type of Pathogen
RNA Viruses
Viral meningitis (aseptic meningitis) Mode of Transmission
Respiratory droplets and feces
Viral meningitis (aseptic meningitis) Key Association
More common than bacterial and fungal meningitis
Poliomyelitis
Major Symptoms
Asymptomatic infections- almost 90% of cases;
Minor polio- nonspecific symptoms;
Nonparalytic polio- muscle spasms and back pain
Paralytic polio (1%)- produces paralysis (can result in bulbar polio)
Poliomyelitis
Causative Organism
Poliovirus
Poliomyelitis
Type of Pathogen
RNA Virus
Poliomyelitis
Mode of Transmission
Transmitted most often by drinking contaminated water (fecal-oral)
Poliomyelitis
Key Associations
aka infantile paralysis; Postpolio syndrome (crippling deterioration) common;
2 vaccines: OPV, IPV (no longer give OPV in US*; FDR dx with Polio
Rabies
Major Symptoms
Pain/itching at site of infection, fever, malaise, anorexia, CNS: hydrophobia, seizures, disorientation, hallucinations, paralysis
Rabies
Causative Organism
Rabies virus
Rabies
Type of Pathogen
RNA Virus
Rabies
Mode of Transmission
Transmission usually occurs via a bite; virus sometimes introduced through break in the skin or inhalation
Rabies
Key Association
Classical zoonotic disease of mammals
Bats- source of most cases of rabies in US; Too late to intervene by the time symptoms occur;
capsid described as “bullet shaped”
Eastern Equine Encephalitis
Major Symptoms
Fever, muscle pain, headache, vomiting, seizures 3-10 days after the bite of an infected mosquito
Eastern Equine Encephalitis
Causative Organism
Eastern Equine Encephalitis (EEE) Virus
Eastern Equine Encephalitis
Type of Pathogen
RNA Virus
Eastern Equine Encephalitis
Mode of Transmission
Mosquito Vector
Eastern Equine Encephalitis
Key Associations
Arbovirus; found mostly East of Mississippi River, more virulent, higher fatality than WEE virus,
BSL-3; aka sleeping sickness
(NOT the same as African Sleeping sickness)
Western Equine Encephalitis
Major Symptoms
Fever, muscle pain, headache, vomiting, seizures 3-10 days after the bite of an infected mosquito
Western Equine Encephalitis
Causative Organism
Western Equine Encephalitis (WEE) Virus
Western Equine Encephalitis
Type of Pathogen
RNA Virus
Western Equine Encephalitis
Mode of Transmission
Mosquito Vector
Western Equine Encephalitis
Key Associations
Arbovirus; found mostly West of Mississippi River; not as virulent or fatal as EEE virus
Venezuelan Equine Encephalitis
Major Symptoms
Fever, muscle pain, headache, vomiting, seizures 3-10 days after the bite of an infected mosquito
Venezuelan Equine Encephalitis
Causative Organism
Venezuelan Equine Encephalitis (VEE) virus
Venezuelan Equine Encephalitis
Type of Pathogen
RNA Virus
Venezuelan Equine Encephalitis
Mode of Transmission
Mosquito vector
Venezuelan Equine Encephalitis
Key Associations
Arbovirus; found primarily in Texas
St. Louis Encephalitis
Major Symptoms
headache, high fever, neck stiffness, stupor, disorientation, coma, tremors, occasional convulsions and spastic paralysis
St. Louis Encephalitis
Causative Organism
St. Louis Encephalitis virus
St. Louis Encephalitis
Type of Pathogen
RNA Virus
St. Louis Encephalitis
Mode of Transmission
Mosquito Vector
St. Louis Encephalitis
Key Associations
Arbovirus; named after outbreak in St. Louis
West Nile Encephalitis
Major Symptoms
80% of people asymptomatic; fever, headache, body aches, nausea, vomiting, sometimes swollen lymph glands or a skin rash on the chest, stomach, back
West Nile Encephalitis
Causative Organism
West Nile Virus
West Nile Encephalitis
Type of Pathogen
RNA Virus
West Nile Encephalitis
Mode of Transmission
Mosquito Vector
West Nile Encephalitis
Key Associations
Arbovirus; avoid handling dead birds
California (LaCrosse) Encephalitis
Major Symptoms
Initial viremia then encephalatis, fever, or rash; symptoms are usually mild
California (LaCrosse) Encephalitis
Causative Organism
California encephalitis virus
California (LaCrosse) Encephalitis
Type of Pathogen
RNA Virus
California (LaCrosse) Encephalitis
Mode of Transmission
Mosquito Vector
California (LaCrosse) Encephalitis
Key Associations
Arbovirus
Tick Borne Encephalitis
Major Symptoms
Sore muscles, fever, then encephalitis, with coma, convulsions, and paralysis
Tick Borne Encephalitis
Causative Organism
Tick Borne Encephalitis Virus
Tick Borne Encephalitis
Type of Pathogen
RNA Virus
Tick Borne Encephalitis
Mode of Transmission
Hard Tick Vector
Tick Borne Encephalitis
Key Associations
Arbovirus; Emerging disease
Cryptococcal meningitis
Major Symptoms
Similar to bacterial meningitis: headache, dizziness, drowsiness, irritability, confusion, nausea, vomiting, neck stiffness- can progress to loss of vision and coma
Cryptococcal meningitis
Causative Organism
Cryptococcus neoformans
Cryptococcal meningitis
Type of Pathogen
Fungus
Cryptococcal meningitis
Mode of Transmission
Opportunistic pathogen- inhalation of spores or dried yeast cells
Cryptococcal meningitis
Key Associations
Most common clinical form of Cryptococcal infection
Mycetismus
Major Symptoms
neurological dysfunction, hallucinations, organ damage, or death
Mycetismus
Causative Organism
Amanita phalloides
Gyromitra esculenta
Psilocybe cubensis
Mycetismus
Type of Pathogen
Ingestion
Mycetismus
Amanita phalloides
Key Associations
“Death cap mushroom”
-deadliest mushroom toxin
Mycetismus
Gyromitra esculenta
Key Associations
“False Morel”
Mycetismus
Psilocybe cubensis
Key Associations
- Hallucinogenic* (psilocybin);
* “magic mushrooms” or “shrooms”*
African Sleeping Sickness
AKA
Trypanosomiasis
African Sleeping Sickness (Trypanosomiasis)
Major Symptoms
3 stages: site of fly bite becomes lesion; Fever, lymph node swelling, and headaches; Invasion of CNS = Meningoencephalitis
African Sleeping Sickness (Trypanosomiasis)
Causative Organism
Trypanosoma bruccei gambiense
Trypanosoma bruccei rhodesiense
African Sleeping Sickness (Trypanosomiasis)
Type of Pathogen
Protozoan
African Sleeping Sickness (Trypanosomiasis)
Mode of Transmission
Tsetse fly vector
African Sleeping Sickness (Trypanosomiasis)
Trypanosoma bruccei gambiense
Key Associations
West African sleeping sickness; more common (95%)
African Sleeping Sickness (Trypanosomiasis)
Trypanosoma bruccei rhodesiense
Key Associations
East African sleeping sickness; less common (5%)
Amebic Meningo-encephalopathy
Major Symptoms
Severe headache, fever, vomiting, neurolocial tissue destruction lead to hemorrhage, coma and usually death within 3-7 days
Amebic Meningo-encephalopathy
Causative Organism
Acanthamoeba
Naegleria fowleri
Amebic Meningo-encephalopathy
Type of Pathogen
Protozoan
Amebic Meningo-encephalopathy
Mode of Transmission
Inhalation of contaminated water
Amebic Meningo-encephalopathy
Acanthamoeba
Key Associations
By the time diagnosed, almost always too late for effective treatment
Amebic Meningo-encephalopathy
Naegleria fowleri
Key Associations
aka “Brain-eating amoeba”;
By the time diagnosed, almost always too late for effective treatment
Variant Creutzfeldt-Jakob Disease (vCJD)
Major Symptoms
Insomnia, weight loss, memory failure, progressive worsening of muscle control
Variant Creutzfeldt-Jakob Disease (vCJD)
Causative Organism
Abnormal strains of prion
Variant Creutzfeldt-Jakob Disease (vCJD)
Type of Pathogen
Prion
Variant Creutzfeldt-Jakob Disease (vCJD)
Mode of Transmission
Most likely from eating BSE contaminated beef
Variant Creutzfeldt-Jakob Disease (vCJD)
Key Associations
Spongiform encephalopathy; Emergin disease
Trachoma
Major Symptoms
Eyelids to turn inward, eyelashes abrade, irritate and scar the cornea, triggering invasion of blood vessels; eventual result is blindness
Trachoma
Causative Organism
Chlamydia trachomatis
Trachoma
Type of Pathogen
Bacteria
Trachoma
Mode of Transmission
Bacteria from genitals introduced to the eyes in birth canal, via fomites or fingers
Trachoma
Key Associations
Leading cause of nontraumatic blindness in humans
Sty
Major Symptoms
Infection of hair follicle on eyelid
Sty
Causative Organism
Staphylococcus aureus
Staphylococcus epidermidis
Sty
Staphylococcus aureus
Type of Pathogen
Bacteria (Gram +)
Sty
Staphylococcus epidermidis
Type of Pathogen
Bacteria (Gram +)
Sty
Mode of Transmission
Direct contact/fomites
Sty
Staphylococcus aureus
Key Association
more likely cause
Opthalmia Neonatorum
Major Symptoms
Inflammation of cornea or blindness
Opthalmia Neonatorum
Causative Organism
Neisseria gonorrhoeae
Opthalmia Neonatorum
Type of Pathogen
Bacteria (Gram -)
Opthalmia Neonatorum
Mode of Transmission
Bacteria from genitals introduced to the eyes in birth canal
Opthalmia Neonatorum
Key Associations
aka Newborn conjunctivitis
Conjunctivitis
AKA
Pinkeye
Conjunctivitis (pinkeye)
Major Symptoms
Red eye, irritation and watering of the eyes are symptoms common to all forms; bacteria causes marked grittiness/irritation and a mucopurulent discharge
Conjunctivitis (pinkeye)
Causative Organism
Staphylococcus aureus
Streptococcus pneumoniae
Haemophilus aegyptii
Adenovirus
Conjunctivitis (pinkeye)
Staphylococcus aureus
Type of Pathogen
Bacteria (Gram +)
Conjunctivitis (pinkeye)
Streptococcus pneumoniae
Type of Pathogen
Bacteria (Gram +)
Conjunctivitis (pinkeye)
Haemophilus aegyptii
Type of Pathogen
Bacteria (Gram -)
Conjunctivitis (pinkeye)
Adenovirus
Type of Pathogen
DNA Virus
Conjunctivitis (pinkeye)
Mode of Transmission
Direct transmission
Conjunctivitis (pinkeye)
Adenovirus
Key Associations
“Swimming pool conjunctivitis”
Ocular herpes
Major Symptoms
Unilateral, gritty feeling, conjunctivitis, pain, sensitivity to light, corneal lesions- can lead to blindness
Ocular herpes
Causative Organism
HHV - 1
aka Herpes Simplex
Ocular herpes
Type of Pathogen
DNA Virus
Ocular herpes
Mode of Transmission
CLose contact with active lesions
Ocular herpes
Key Associations
Latent virus in trigeminal ganglion travels down ophthalmic branch
Ocular candidiasis
Major Symptoms
Eye pain, red eye, blindness
Ocular candidiasis
Causative Organism
Candida albicans
Ocular candidiasis
Type of Pathogen
Fungus
Ocular candidiasis
Mode of Transmission
Opportunistic pathogen
Acanthamoeba keratitis
Major Symptoms
Extreme eye pain, severe redness
Acanthamoeba keratitis
Causative Organism
Acanthamoeba
Acanthamoeba keratitis
Type of Pathogen
Protozoan
Acanthamoeba keratitis
Mode of Transmission
Enters through cuts, scrapes, conjunctiva
Acanthamoeba keratitis
Key Associations
Prevent by NEVER using non-sterile solutions to clean or store contact lenses; Emerging disease
Loa Loa Filariasis
Major Symptoms
Doesn’t normally affect vision, can be painful when moving about the eyeball or across the bridge of teh nose;
Swelling below skin called Calabar swellings
Loa Loa Filariasis
Causative Organism
Loa Loa
Loa Loa Filariasis
Type of Pathogen
Nematode
roundworm
Loa Loa Filariasis
Mode of Transmission
Deer fly or Mango fly vectors
Loa Loa Filariasis
Key Associations
aka subcutaneous filariasis or loaiasis
Onchocerciasis
Major Symptoms
Long-term corneal inflammation; leads to blindness
Onchocerciasis
Causative Organism
Onchocerca valvulus
Onchocerciasis
Type of Pathogen
Nematode
Roundworm
Onchocerciasis
Mode of Transmission
Black-fly Vector
Onchocerciasis
Key Associations
aka River Blindness