Micro II exam 5

the smallest free living bacteria known

they have no cell wall

causes Mycoplasma sp. to be flexible & pleomorphic

the colonies under a dissecting microscope have a "fried-egg" shape

causes primary atypical pneumonia

transmitted via droplet spray or contact with contaminated respiratory secretions

tends to affect school-aged children and young adults

rarely adults over the age of 50

these are urethral normal flora organisms of sexually active humans

may cause several different infections of the reproductive systems

similar to a gram-negative coccobacillus

are obligate intracellular parasites of man and certain arthropod vectors

they are small in size and are barely visible under a normal light microscope

rickettsia lack certain external structures associated with other bacteria

rickettsia cause several diseases that have as characteristics

the diseases of _____________ organisms are difficult to diagnose because the symptoms are similar to many other diseases...and...the organisms are dangerous to work with

it has been found that the genus of bacteria ___________ has an antigen in its cells that is also present in _________

Proteus is less fdangerous to work with, a diagnosis of a rickettsial disease can be performed by testing for the presence of the shared antigen

caused by Rickettsia prowazekii

transmitted from host to host via the human body louse

a louse takes a blood meal from a person with typhus fever

the rickettsia line the intestinal lining of the louse

when the louse feeds again on another human host, it defecates

leaving the skin contaminated with rickettsia

the bite itches and the wound is infected when the organism is ground in by scratching

characterized by a mental dullness or stupor caused by the high fever

symptoms include:
1. unbearable headache
2. chills
3. muscle ache
4. rash over the entire body EXCEPT:
   a. face
   b. palms pf hands
   c. soles of feet

caused by Rickettsia typhi

transmitted from host to host via the rat flea

because the disease is endemic to rats and mice

the disease is similar to Epidemic typhus but is much less severe and rarely causes death

caused by Rickettsia rickettsii

transmitted from host to host via a tick

the tick becomes infected by biting a diseased animal or by passage of the disease from a mother tick to her offspring

children are the most likely to contract the disease

adults are more likely to die

symptoms include:
1. flu-like aches & pains
2. headache
3. light sensitivity
4. chills
5. confusion
6. several days of high fever
7. a characteristic reddish to black rash

starts on the extremities

particularly on palms of hands and the soles of feet

the rash signifies that the organism is multiplying in and destroying the endothelial cells of capillaries

allows for the escape of RBC into the surrounding tissues causing the rash

a common complication is that the disease cannot be diagnosed at the onset because the symptoms resemble those of many other diseases

delayed treatment

caused by Rickettsia tsutsugamushi (orientia)

transmitted from host to host via a mite similar to a chigger

symptoms include:
1. severe headache
2. chills
3. fever
4. characteristic rash called an eschar

a rash that causes

a sloughing off of the skin

a rickettsial disease caused by coxiella burnetti

transmitted from host to host in three ways:
1. by inhallation
2. by ingestion of raw milk
3. by the bite of several types of ticks

because the organism is highly resistant to heat, light, and drying

does NOT REQUIRE an arthropod vector like other rickettsial diseases

a gram-negative coccobacillus

obligate intracellular parasites

have a complex reproduction process that forms the infectious agents called elementary bodies

also know as Ornithosis, parrot fever, or chlamydial pneumonia

caused by Chlamydia psittaci

transmitted via inhalation of dust from the feces of virtually any type of bird

1. wildbirds
2. farm birds
3. pets

causes an influenza-like infection with:
1. headache
2. fever
3. cough

can be life-threatening with symptoms of:
1. persistent high fever
2. mental confusion
3. SOB

known as inclusive conjunctivitis

Chlamydia trachomatis

transmitted by direct contact with contaminated fingers, towels, or clothing

the word trachoma means

a description of granular, pebble-like texture of the infected conjunctiva

the inflammation process results in scarring of the cornea causing blindness

this is the number one preventable cause of blindness worldwide

climatic bubo

VD

caused by Chlamydia trachomatis

first manifests as a small lesion on the genitals

second, moves to the regional lymph nodes of the inguinal area

third, causes the nodes to become swollen, inflamed, & necrotic

lastly, will eventually disfigure the external genitalia because of lymphatic obstruction

the most frequent cause of gonorrhea negative urethritis

an STD that produces a chronic urethral discharge and inflammation for up to a year

Will disfigure the external genitalia

Which is more severe?... ... . Epidemic or Endemic typhus fever

The most frequent cause of gonorrhea negative urethritis

Sloughing off of the skin

Rickettsia line the intestinal lining of the louse

Rough

Scarring of the cornea

Louse defecates when eating

Lack flagella, pili, capsules, and spores

Number one preventable cause of blindness worldwide

Starts as small lesions on the genitals and moves to regional lymph nodes

Causes an influenza-like infection

A rickettsial disease caused by a genus other than Rickettsia

Granular, pebble-like texture of the conjunctiva

A venereal disease

Causes a rash called an eschar

Bite wound itches and we grind the organism into our skin by scratching

A rash that covers the entire body EXCEPT the face, palms of the hands, and soles of the feet

A characteristic reddish to black rash

Can be diagnosed by the Weil-Felix test

Has a cellular antigen similar to that of Proteus?

No cellwall

Smallest "free-living" bacteria known.

Fried-egg shape of colonies

Flexible and pleomorphic

Rarely atfects adults over 50... usually school-aged children and young adults

Urethral normal flora organism of sexually active humans

Infectious agents are the elementary bodies

Dust of bird feces

Characterized by mental dullness and a stupor caused by the high fever

Disease is endemic to rats and mice

A rash that covers the entire body PARTICULARLY the palms of the hands and soles of the feet

Light sensitivity is a symptom

Destroys the endothelial cells of capillaries

Causes a chronic urethral discharge and inflammation for up to a year

lntermediate in size between bacteria and viruses(2)

Small in size and barely visible under a normal light microscope(2)

Children are most likely to contract it but adults are more likeiy to die

Distinctive features of the disease include a high fever and skin rash