Chapter 1.13 Chlamydia, Rickettsia, and Friends Flashcards
What is the cell characteristics of Chlamydia and Rickettsia?
gram-negative
obligate intracellular parasite
What does an obligate intracellular parasite mean?
can only survive by establishing “residence” inside animal cell
What makes Chlamydia and Rickettsia energy parasites?
they use a cell membrane transport system that steals ATP from the host and gives off ADP
What is the difference in ATP production between Chlamydia and Rickettsia?
Rickettsia can can make ATP
Chlamydia can NOT
What is the difference between Chlamydia and Rickettsia and viruses?
Chlamydia and Rickettsia have both RNA and DNA
Viruses only have either RNA or DNA
Why is Chlamydia different that normal gram-negative bacteria?
does not have peptidoglycan layer
What infections does Chlamydia cause?
conjunctivitis, cervicitis, and pneumonia
What are the 2 forms of Chlamydia?
Elementary body and initial body
What are the characteristics of the elementary body of Chlamydia?
does not divide, dense, round, small, infectious
exists extracellularly
What are the characteristics of the initial body of Chlamydia?
also called reticulate body RNA content increases binary fission occurs synthesizes its own DNA, RNA, proteins *needs ATP from the host
What is the life cycle of Chlamydia?
a. elementary body attaches and enters columnar, mucus membranes of epithelial cells
b. in endosome, EB inhibits phagosome-lysosome fusion and transforms into initial body
c. form many IBs and some change back into EBs
d. completed cycle when host cell liberates the EB which can infect more cells
What are the 3 species of Chlamydia that cause human disease?
Chlamydia trachomatis
Chlamydia psittaci
Chlamydia pneumonia
What does Chlamydia trachomatis primarily infect?
eyes and genitals
What disease is associated with Chlamydia trachomatis?
Trachoma
What is trachoma?
type of chronic conjunctivitis that is the leading cause of preventable blindness (takes 10-15 years)
Who is most susceptible to trachoma?
poverty regions, underdeveloped countries
How is Chlamydia trachomatis transmitted?
hand-to-hand transfer of infected eye secretions
What is the most common sexually transmitted disease in the U.S.?
Chlamydia trachomatis
What is inclusion conjunctivitis?
infection that babies delivered through the birth canal get from mothers infected with Chlamydia trachomatis
What is the clinical presentation of a baby with inclusion conjunctivitis?
conjunctival inflammation
yellow purulent discharge
swelling of the eyelids in 5-14 days after birth
What is the diagnosing factor for inclusion conjunctivitis?
intracytoplasmic inclusion bodies
How does chlamydial pneumonia occur in babies?
babies that pass through infected birth canal
What is the clinical presentation of a baby with chlamydial pneumonia?
occurs between 4-11 weeks of life upper respiratory symptoms rapid breathing cough respiratory distress
How is a diagnosis of chlamydial pneumonia made?
presence of anti-chlamydial IgM antibodies
What is urethritis?
infection of the urethra
What causes urethritis?
Neisseria gonorrhoeae is the most famous but not the most common
*Urethritis that is not caused by Neisseria honorrhoeae is called nongonococcal urethritis (NGU) and is caused by Chlamydia trachomatis
What is the clinical presentation of symptomatic patient with NGU?
painful urination
thin to thick, mucoid discharge from urethra
How does the cervix appear when infected with Chlamydia trachomatis?
red, swollen, yellow mucopurulent endocervical discharge
What 2 bacteria can cause pelvic inflammatory disease (PID)?
Chlamydia trachomatis and Neisseris gonorrhoeae
What are the clinical manifestations of a woman with PID?
abnormal vaginal discharge or uterine bleeding
pain with sexual intercourse
nausea
vomiting
fever
*most common symptom- lower abdominal pain
What is the PID shuffle?
small, widebased steps to minimize shaking of the abdomen
What is the Chandelier sign?
cervical motion tenderness that is so sever a patient leaps to the chandelier
*woman with PID
What are the results of PID?
fallopian tube scarring which can cause infertility, ectopic pregnancy and chronic pelvic pain
What is chlamydial epididymitis?
an infection in men with urethritis
What is the clinical presentation of man with chlamydial epididymitis?
unilateral scrotal swelling, tenderness, and pain, associated with fever
What is Reiter’s syndrome?
Inflammatory arthritis of large joints that is associated with Chlamydia trachomatis
Seen in men between 20-40
What is Fitz-Hugh-Curtis syndrome?
infection of the liver capsule that is associated with chlamydial or gonococcal infection
What is the clinical presentation of a patient with Fitz-Hugh-Curtis syndrome?
right upper quadrant pain
can occur in men and women
What is Lymphogranuloma Venereum?
sexually transmitted disease caused by Chlamydia trachomatis
What is the clinical presentation of a patient with Lymphogranuloma Venereum?
painless papule (bump) or ulceration on genitals that heals –> enlarges lymph nodes over next 2 months that may break open and drain pus
How are humans infected with Chlamydiophila psittaci?
inhaling chlamydia-laden dust form feathers or dried out feces
Who is at risk for Chlamydiophila psittaci?
breeders of carrier pigeons, veterinarians, and pet-shop workers or poultry slaughterhouses
What infection is associated with Chlaymdiophila psittaci?
atypical pneumonia called psittacosis that occurs 1-3 weeks after exposure
What viruses cause atypical pneumonia?
Myoplasma pneumoniae and Chylamydophilia
What is the clinical presentation of a patient with atypical pneumonia?
dry cough, fever, less sick appearing
What is the single species of Chlamydiphila pneumonia?
TWAR- TaiWan and Acute Respiratory
How is Chlamydiphila pneumonia transmitted?
from person to person by respiratory route
What infection does Chlaymdiphila pneumonia cause?
atypical pneumonia in young adults world wide
What is the cell characteristics of Rickettsia?
small, gram-negative, non-motile, rod-to-coccoid shape bacterium
How does Rickettsia differ from Chlamydia?
- requires arthropod vector
- replicates freely in cytoplasm (Chlamydia replicates in endosome)
- has tropism for endothelial cells that lines blood vessels (Chlamydia likes columnar epithelium)
- cause different diseases
What symptoms does Rickettsia cause?
rashes, high fevers, and bad headaches
What bacteria does Rickettsia share antigenic characteristics with?
Proteus vulgaris even though they have no relation in disease
What bacteria is involved in a positive Weil-Felix test?
Rickettsia
What is the common name for Rickettsia rickettsii?
Rocky Mountain Spotted Fever
How does Rocky Mountain Spotted Fever occur?
a person is bitten by a deer rick or dog tick
*present within a week after bite
What is the clinical presentation of a person with Rocky Mountain spotted fever?
fever, conjunctival redness, severe headache, rash on wrists, ankles, soles, and palms which later spreads to trunk
What disease does Rickettsia akari cause?
rickettsialpox
How is Rickettsia akari transmitted to humans?
via mites that live on house mice
What is the clinical presentation of rickettsialpox?
initail localize red skin bump at site of bite, the bump turns into a blister, and later a fever and headache develop, other blisters appear over the body
What disease is caused by Rickettsia prowazekii?
epidemic (sudden onset and rapid spread) form of typhus
What disease is caused by Rickettsia typhi?
endemic (constant existence of infection) form of typhus
How is Rickettsia prowazekii transmitted to humans?
via lice
What is the clinical presentation of a person infected with Rickettsia prowazekii?
epidemic typhus
abrupt onset of fever, headache 2 weeks after exposure
small pink macules on upper trunk and whole body
delirium and stuporous
What is Brill-Zinsser Diesase?
Breakout of Rickettsia prowazekii from latent state
*milder (no skin rash) symptoms
How is Rickettsia typhi transmitted to humans?
via rat flea
What is the clinical presentation of a patient with Endemic typhus?
fever, headache, flat and bumpy rash
What disease is caused by Rickettsia tsutsugamushi?
Scrub typhus or Tsutsugamushi Fever
Who is most susceptible to Rickettsia tsutsugamushi?
soilders in the South Pacific and in Vietnam
How is Ricketsia tstugamusi transmitted to humans?
spread by the bite of larvae (chiggers) of mites
*mites live on rodents and larval chiggers live in soil
What is the clinical presentation of a patient with Scrub Typhus?
high fever, headache, and scab at original bite site
later, a flat and bumpy rash develops
What is the clinical presentation of patient with Rickettsia parkeri?
fever, headaches, eschars (dead tissue), regional lymphadenopathy
What disease is associated with Bartonella quintana?
trench fever
What is trench fever?
louse-borne febrile disease from WWI
*louse is a parasite
How is Bartonella quintana different from Rickettsia?
it is NOT an obligate intracellular organism
How was trench fever spread?
in the trenches by the body louse
What is the clinical presentation of patient with trench fever?
high fever, rash, headache, severe back and leg pains
*appeared recovery but then relapse 5 days later
What disease is associated with Bartonella henselae?
cat-scratch disease
How does cat-scratch disease occur?
following a cat bite or scratch
What is the clinical presentation of cat-scratch diseases?
enlargement of regional lymph nodes, low-grade fever, malasie
What disease is associated with Coxiella burnetti?
Q Fever
What is the difference between Coxiella burnetti and Rickettsia?
Coxiella burnetti has an endospore form
What are the unique characteristics of Coxiella burnetti?
- resistance to heat and drying
- extracellular existence (Chlamydia and Rickettsia must occur intracellularly)
- non-arthropod transmission
- pneumonia
What is the clinical presentation of Q fever?
abrupt onset of fever and soaking sweats 2-3 weeks after infection
