Mycoplasm 1-12

Match the following: 1)sometimes causes postpartum fever and has been found with other bacteria in uterine tube infections. 2)causes pneumonia and has been associated with joint and other infections. 3)causes non-gonococcal urethritis in men and is associated with lung disease in premature infants of low birth weight. 4)closely related to M pneumoniae and has been associated with urethral and other infections A) Mycoplasma pneumoniae B)Mycoplasma hominis C)Ureaplasma urealyticum D)Mycoplasma genitalium

1)B 2)A 3) C 4) D

Mycoplasmas have the following characteristics: The smallest mycoplasmas are ______ nm in size. They are highly pleomorphic because they lack a rigid _____ ______and instead are bounded by a triple-layered "unit membrane" that contains a sterol

125-250 cell wall

True or false: Mycoplasma pneumoniae cause typical pneumonia

False They causes "atypical" pneumonia

Pathogenesis of M. pneumoniae In the lungs, the organism is rod-shaped, with a tapered tip that contains specific proteins that serve as the point of attachment to the respiratory epithelium. True or false? The respiratory mucosa is invaded, ciliary motion is inhibited and necrosis of the epithelium occurs.

False: The respiratory mucosa is not invaded, but ciliary motion is inhibited and necrosis of the epithelium occurs.

____________ produces hydrogen peroxide, superoxide radicals and cytolytic enzymes which contributes to the damage to the respiratory tract cells, leading to necrosis and a bad hacking cough (walking pneumonia)

M. pneumoniae

Extracellular, tiny, flexible No cell wall Not seen on gram stain smear Membrane with cholesterol but does not synthesize cholesterol Requires cholesterol for in-vitro culture Grow slowly and require at least 1 week to form a visible colony Colony frequently has a characteristic "fried-egg" shape, with a raised center and a thinner outer edge. These are the distinguishing features of:

Mycoplasma pneumoniae

Mycoplasma pneumoniae is transmitted by:

Respiratory droplets close contact families, military recruits, schools.

True or false: The mechanism by which M. pneumoniae causes inflammation is well understood and only noobs don't understand the process.

The mechanism by which M. pneumoniae causes inflammation is uncertain (even experts don't know)

True or false: M. pneumoniae has only one serotype and is antigenically distinct from other species of Mycoplasma.

True

They are called Eaton's agent

What is Mycoplasma pneumoniae

Some mycoplasmas lack the distinct tip structures but use _______ proteins or have alternative mechanisms to adhere to host cells.

adhesin

The term "________" means that a causative bacterium cannot be isolated on routine media in the diagnostic laboratory or that the disease does not resemble pneumococcal pneumonia.

atypical

True or false? Mycoplasmas are very small, walled organisms

false very small, wall-less organisms

Mycoplasmas have been cultivated from human mucous membranes and tissues, particularly from the _______,_______ and ________They are part of the normal flora of the mouth and can be grown from normal saliva, oral mucous membranes, sputum, or tonsillar tissue.

genital, urinary, and respiratory tracts.

The onset of Mycoplasma pneumonia is gradual, usually beginning with a _______ cough, sore throat, or earache. The incubation period varies from ____ to ____ weeks

nonproductive, 1 to 3

M salivarium, M orale, and other mycoplasmas can be recovered from the _____ cavities of many healthy adults, but an association with

oral

M pneumoniae in the _______is generally associated with disease

oropharynx

During M. pneumoniae infection, autoantibodies are produced against____ _____ and brain, lung, and liver cells.

red cells (cold agglutinins)

Mycoplasma pneumoniae attach to the surfaces of ciliated and non-ciliated cells, probably through the mucosal cell _________ and __________.

sialoglycoconjugates and sulfated glycolipids.

Mycoplasmas are completely resistant to penicillin because they lack the cell wall structures at which penicillin acts, but they are inhibited by ________ or ______

tetracycline or erythromycin.

True or false: Mycoplasma pneumonia is the most common type of atypical pneumonia.

true

True or false: Mycoplasmas pneumoniae are the smallest organisms that can be free-living in nature and self-replicating on laboratory media

true