Term
Pyogenic Osteomyelitis reach bone by... |
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Definition
hematogenous spread, extension from a contiguous site, direct implantation |
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Term
Osteomyelitis spread in children |
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Definition
Hematogenous in origin, develops in long bones, injury to mucosa, minor infection of skin |
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Term
Osteomyelitis spread in adults |
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Definition
Complication of open fractures, surgical procedures, diabetic infections of foot |
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Term
Most common organism in pyogenic osteomyelitis |
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Definition
Staph. aureus, organisms express receptors for bone matrix components such as collagen |
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Term
Pyogenic osteomyelitis organisms from individuals with genitourinary tract infections or IV drug users |
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Definition
E. Coli, Pseudomonas, Klebsiella |
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Term
Neonatal pyogenic osteomyelitis |
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Definition
H. influenzae, group B steptococci |
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Term
Pyogenic osteomyelitis organism for those w/sickle cell |
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Definition
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Term
Areas of bone infected in:
1. neonates
2. children
3. adults |
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Definition
1. metaphysis, epiphysis or both
2. metaphysis, long bones w/vascularity
3. metaphysis, epiphysis, subchondral regions, vertebral |
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Term
Time period for which bone undergoes necrosis in pyogenic osteomyelitis |
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Definition
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Term
What is the dead piece of bone in osteomyelitis called? |
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Definition
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Term
Consequences of epiphyseal infection in infants |
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Definition
Infection spreads through the articular surface or along capsular and tendoligamentous insertions into a joint, producing septic arthritis, also happens in vertebrae |
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Term
Symptoms after first week of osteomyelitis infection |
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Definition
Osteoclastic bone resorption, deposition of reactive bone |
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Term
Name of sleeve of living tissue around segment of devitalized infected bone |
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Definition
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Term
Morphologic variants of osteomyelitis |
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Definition
Brodie abcess (sequestered focus of staph osteomyelitis in long bone of adults), sclerosing osteomyelitis of Garre |
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Term
Osteomyelitis radiologic findings |
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Definition
Lytic focus of bone destruction surrounded by a zone of sclerosis |
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Term
Tuberculous Osteomyelitis Spread |
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Definition
Usually blood borne and originate from a focus of active visceral disease during intial stages of primary infections, may also occur from direct extension or draining lymphatics |
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Term
Most common sites tuberculous osteomyelitis
irreversible inhibitor of COX-1 and COX-2
covalent modification of enzyme (acetylation of ser residue)
toxicity:
ti |
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Definition
Spine (Pott disease), then knees and hips |
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Term
tuberculous osteomyelitis symptoms |
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Definition
pain on motion, tenderness, low-grade fevers, chills, weight loss, arthritis, sinus tract formation, psoas abscess, amyloidosis |
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Term
Where do spirochetes localize in congenital skeletal syphilis? |
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Definition
areas of active endochondral ossification and in the periosteum |
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Term
Most frequently involved bones in skeletal syphilis |
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Definition
nose, palate, skill, extremities |
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Term
Massive reactive periosteal bone deposition on medial and anterior surfaces of tibia in syphilis is called what? |
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Definition
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Term
Form of reactive arthritis defined by traid of arthritis, nongonococcal urethritis or cervicitis, and conjunctivitis |
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Definition
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Term
Reiter Syndrome caused by autoimmune rxn initiated by prior infection of what? |
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Definition
GI tract and genitourinary system |
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Term
Enteritis-Associated Arthritis caused by what? What specifically on these organisms? |
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Definition
GI infection by Yersinia, Salmonella, Shigella, Campylobacter
Outer cell membranes w/LPS |
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Term
Chronic inflammatory arthropathy that affects peipheral and axial joints and entheses |
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Definition
Psoriatic Arthritis, like rheumatoid arthritis, but not as severe |
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Term
Lyme arthritis is caused by what organism |
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Definition
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Term
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Definition
late, involves large joints |
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Term
Most common organism of arthritis in sexually active people |
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Definition
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Term
Borrelia are what type of bacteria? |
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Definition
weakly staining, gram-negative spirochetes |
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Term
Borrelia nutritional needs? movement? |
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Definition
microaerophilic, periplasmic flagella responsible for twisting motility |
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Term
Outer surface protein functions in Borrelia |
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Definition
OspA expressed in midgut of unfed ticks and binds gut proteins, repressed during feeding and OspC expressed to move to salivary glands and into mammals |
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Term
What is the leading vector-borne disease in the US? |
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Definition
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Term
Where is the three principal foci of infection in the US? |
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Definition
Northeast, Mid-Atlantic States, Pacific West |
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Term
What are the major vectors of Lyme disease? |
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Definition
Hard ticks, Ixodes scapularis in NE, mid-Atlanta, and Midwest and Ixodes pacificus on west Coast |
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Term
What are the major hosts of Lyme disease in US? |
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Definition
White-footed mouse- larval and nymph forms of Ixodes
White-tailed deer- adult Ixodes |
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Term
When can humans be infected and in what lifestage of the organism? |
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Definition
Second blood meal in spring by nymph and third blood meal in late summer by adults |
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Term
What is the lesion called that develops from the site of a tick bite? |
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Definition
Erythema migrans, not pathognomonic |
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Term
Early signs of Lyme disease |
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Definition
malaise, severe fatigue, headache, fever chills, musculoskeltal pains, myalgias, lymphadenopathy for an avg. of 4 weeks |
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Term
Clinial Case Definition of Lyme Disease |
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Definition
Either of the following:
Erythema migrans
At least one late manifestation (musculoskeletal, nervous, cardiovascular involvement) and laboratory confirmation of infection |
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Term
Laboratory Criteria for Diagnosis |
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Definition
At least one of the following:
Isolation of Borrelia burgdorferi
Demonstration of diagnostic levels of IgM or IgG antibodies to the spirochetes
Significant increase in antiboy titer between acture and convalescent serum samples |
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Term
Is B. burgdorferi seen in clinical specimens? |
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Definition
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Term
What is the diagnostic test of choice for Lyme disease? |
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Definition
serologic testing, specifically IFA and EIA, tests for later stages |
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Term
Early manifestations of Lyme disease treated with what? |
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Definition
amoxicillin, doxycycline, cefuroxime |
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Term
Recurrent arthritis from Lyme disease or central or peripheral nervous system treated with what? |
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Definition
ceftriaxone, cefotaxime, penicillin G |
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Term
How should those with chronic symptoms of Lyme disease be treated? |
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Definition
symptomatically, no more antibiotics |
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Term
What type of bacteria are Clostridium? |
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Definition
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Term
What is the structure of C. tetani? |
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Definition
large, motile, spore-forming rod that produces round, terminal spores like a delicious drumstick |
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Term
Why is C. tetani difficult to grow? |
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Definition
Because of oxygen toxicity |
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Term
What are the two types of C. tetani toxins? |
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Definition
Tetanolysin- an oxygen-labile hemolysin
Tetanospasmin- a plasmid-encoded, heat labile neurotoxin, nonconjugative |
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Term
Which C. tetani toxin is responsible for clinical manifestations of tetanus and how? |
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Definition
Tetanospasmin (A-B toxin), produced during stationary phase of growth, released when cell is lysed, carbohydrate-binding domain of heavy chain, carboxyl-terminal portion, binds to specific sialic acid receptors and adjacent glycoproteins on presynaptic membrane of motor neurons |
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Term
How does tetanospasmin travel once attached to motor neurons? |
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Definition
internalized in endosomal vesicles and transported in neuron axon to motor neuron soma in spinal cord by retrograde axonal transport, endosome becomes acidified, conformational change in N-terminus, followed by insertion into endosome membrane and passage of toxin light chain into cytosol of cell |
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Term
How does tetanospasmin work? |
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Definition
Light chain is a zinc endopeptinase that inactivates proteins like synaptobrevin that regulate release of inhibitory neurotransmitters which leads to unregulated excitation and spastic paralysis, irreversible |
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Term
Where is C. tetani found? |
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Definition
fertile soil and in GI tracts of many animals |
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Term
How does C. tetani survive even though it is extremely susceptible to oxygen toxicity? |
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Definition
spores, also aided by necrotic tissue, calcium salts, pyogenic infections |
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Term
How is the duration of the incubation period of C. tetani determined? |
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Definition
Distance of primary wound to CNS |
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Term
What is presenting sign generalized tetanus in most C. tetani patients? |
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Definition
involvement of masseter muscles (trismus and lockjaw), sardonic smile (risus sardonicus), drooling, sweating, irritability, back spasms |
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Term
How is C. tetani diagnosed? |
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Definition
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Term
What is the structure and physiology of C. botulinum? |
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Definition
large, heterogenous, fastidious, spore-forming, anaerobic |
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Term
Human disease is associated w/what types of C. botulinum? |
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Definition
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Term
What are the characteristics of C. botulinum toxin? |
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Definition
Has zinc-endopeptidase activity and a large, nontoxic subunit
Complexed w/nontoxic proteins that protect the neurotoxin during passage through the digestive tract |
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Term
How does the C. botulinum toxin get into cells and cause harm? |
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Definition
From gut, carboxyl-terminal portion of heavy chain binds to sialic acid receptors and glycoproteins on presynaptic membrane of motor neuron of peripheral and cranial nerves, endocytosis, remains at neuromuscular junction, release of light chain, inactivates SNARE proteins (synaptobrevin, SNAP 25, syntaxin) that regulate ACh, leading to flaccid paralysis |
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Term
Where is C. botulinum found? |
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Definition
soil and water
Type A- neutral or alkaline soil west of Mississippi
Type B- easter part of country in rich, organic soil
E- wet soil
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Term
What are the 4 types of botulism found in US? |
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Definition
1. classic of foodborne- consumption of home-canned foods (A and B) and preserved fish (E)
2. infant botulism- consumption of foods w/spores, honey, milk powder, soil
3. wound botulism
4. inhalation botulism- major concern for bioterrorism |
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Term
What are the initial signs of foodborne botulism? |
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Definition
blurred vision w/fixed, dilated pupils, dry mouth, constipation, and abdominal pain |
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Term
What are the progressive signs of foodborne botulism? |
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Definition
Bilateral descending weakness of peripheral muscles, respiratory paralysis |
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Term
How do patients recover from C. tetani and C. botulinum? |
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Definition
wait for affected nerve endings to regrow |
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Term
What is the most common form of botulism in US? |
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Definition
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Term
Where does C. botulinum become established in infants? |
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Definition
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Term
How can you isolate the C. botulinum specimen? |
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Definition
heat specimen for 10 min. at 80 degrees to kill all nonclostridial cells |
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Term
What are the treatment measures for botulism? |
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Definition
1. adequate ventilatory support
2. elimination of organism from GI tract through gastric lavage and metronidazole or penicillin
3. use of trivalent botulinum antitoxin |
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Term
Lymphocutaneous Sporotrichosis is cause by what organism? |
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Definition
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Term
True or False: S. schenckii is thermally dimorphic. |
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Definition
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Term
Where is sporotrichosis normally found? |
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Definition
warmer climates, Japan, Mexico, Brazil, Uruguay, Peru, Clumbia
outbreaks related to forest work, mining, and gardening
zoonotic transmission through armadillo hunters and infected cats |
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Term
When does lymphangitic sporotrichosis classically appear? |
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Definition
following local trauma to an extremity |
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Term
What are the symptoms of sporotrichosis? |
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Definition
primary skin lesions in a linear chain along lymphatic drainage |
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Term
In what conditions does the S. schenckii grow as a mold? yeast? |
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Definition
room temp, body temp (pleomorphic)
Appearance of Splendore-Hoeppli material surrounding yeast cells |
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Term
What is the treatment for lymphocutaneous sporotrichosis? |
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Definition
oral potassium iodide in saturated solution which has frequent adverse side effects
itraconazole also effective
fluconazole last resort |
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Term
What are the characteristics of Chromoblastomycosis? |
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Definition
chronic fungal infection affecting skin and subcutaneous tissues, characterized by development of slow-growing verrucous nodules or plaques |
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Term
Where is Chromoblastomycosis normally seen? |
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Definition
in tropics, where warm, moist environment coupled w/lack of footwear or clothing predisposes individuals to direct inoculation w/infected soil or organic matter |
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Term
What organisms are associated w/Chromoblastomycosis? |
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Definition
Fonsecaea, Cladosporium, Exophiala, Cladophialophora, Rhinocladiella, Phialophora |
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Term
What is the common characteristic of all fungi that cause Chromoblastomycosis in tissue? |
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Definition
All form muriform cells that are chestnut brown due to melanin in their cell walls, these cells divide by internal septation and appear as cells with vertical and horizontal lines |
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Term
What is the most common cause of Chromoblastomycosis in US? |
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Definition
Fonsecaea pedrosoi, most often involves lower extremities |
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Term
What are the clinical syndromes of Chromoblastomycosis? |
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Definition
chronic, pruritic, progressive, indolent, and resistant to treatment
Early lesions are small, warty papules and enlarge as multiple, large, cauliflower-like growths
Large lesions are hyperkeratotic |
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Term
What prep helps identify causative agent of Chromoblastomycosis in scrapings of warty lesions? |
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Definition
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Term
What are the most effective drugs for Chromoblastomycosis? |
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Definition
Itraconazole and terbinafine, posaconazole more recently
Squamous cell carcinomas may develop |
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Term
What is eumycotic mycetoma characterized by? |
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Definition
formation of multiple granulomas and abscesses that contain large aggregates of fungal hyphae known as granules or grains, drain through skin |
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Term
What are the etiologic agents for eumycotic mycetoma? |
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Definition
Phaeoacremonium, Curvularia, Fusarium, Madurella, Exophiala, Pyrenochaeta, Leptosphaeria, Scedosporium |
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Term
What are the granules of eumycotic mycetoma like? |
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Definition
composed of septate fungal hyphae, frequently distorted and bizarre, large, spherical, thick-walled chlamydoconidia often present
Splendore-Hoepplie material often interdigitates |
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Term
Where is eumycotic mycetoma typically seen? |
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Definition
tropical areas w/low rainfall, more frequent in Africa and Indian subcontinent, also Brazil, Venezuela, Middle East |
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Term
How are patient infected with eumycotic mycetoma? |
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Definition
traumatic percutaneous implantation of etiologic agent into exposed parts of body, men more than women |
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Term
What are the clinical symptoms of eumycotic mycetoma? |
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Definition
Initially small nodule, then sinus tracts on skin and drain serosanguineous fluid that contains granules |
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Term
What is the treatment for eumycotic mycetoma? |
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Definition
hard to treat, usually unsuccessful |
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Term
What is subcutaneous zygomycosis caused by? |
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Definition
Zygomycetes of the order Entomophthorales: Conidiobolus coronatus and Basidiobolus ranarum |
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Term
How does the fungi cause a chronic subcutaneous form of zygomycosis? |
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Definition
Sporadically as a result of traumatic implantation of the fungus present in plant debris in tropical environments |
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Term
Where does B. ranarum cause infection? |
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Definition
Subcutaneous infection of proximal limbs in children |
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Term
Where does C. coronatus cause infection? |
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Definition
Localized to the facial area, primarily in adults |
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Term
What type of fungi are B. ranarum and C. coronatus? |
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Definition
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Term
How are B. ranarum and C. coronatus spread? |
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Definition
B. ranarum- through traumatic implantation of the fungus into subcutaneous tissues of thighs, buttocks, and trunk
C. coronatus- through inhalation of fungal spores, which invades the tissues of the nasal cavity, paranasal sinuses, facial soft tissues
10:1 male to female ratio |
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Term
What is the clinical syndrome of B. ranarum? |
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Definition
Disk-shaped rubbery masses that may be large and localized to shoulder, pelvis, hips, thighs |
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Term
What is the clinical syndrome of C. coronatus? |
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Definition
Infection confined to rhinofacial area |
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Term
What is the treatment for subcutaneous zygomycosis infection? |
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Definition
itraconazole
Oral potassium iodide has been used |
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Term
What is subcutaneous phaeohyphomycosis caused by? |
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Definition
A heterogenous array of fungal infections caused by pigmented, dematiaceous fungi present as irregular hyphae |
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Term
What is the morphology of the agents that cause phaeohyphomycosis? |
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Definition
All grow as black molds in culture and appear as dark-walled, irregular, hyphal and yeastlike forms in tissue
May require Fontana-Masson melanin stain to confirm
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Term
What are the most frequent agents of phaeohyphomycosis? |
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Definition
Exophiala jeanselmei, Alternaria, Curvularia, Phaeoacremonium, Bipolaris |
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Term
Route of infection of phaeohyphomycosis |
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Definition
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Term
How does phaeohyphomycosis most commonly present? |
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Definition
Solitary inflammatory cyst, generally on feet and legs, can also cause brain cysts |
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Term
What is the main treatment for phaeohyphomycosis? |
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Definition
Surgical excision, also can use itraconazole with or w/o concomitant flucytosine |
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Term
What is Lacaziosis caused by? |
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Definition
Lacazia loboi, in the order Onygenales and family Ajellomycetaceae |
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Term
What is the morphology of Lacazia loboi? |
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Definition
double-refractile cell wall, reproduces by budding, some may have one or two secondary buds |
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Term
Where is Lacazia loboi endemic? |
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Definition
tropical regions of Central and South America, saprophyte of soil in thick vegetation such as the Amazon rain forest |
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Term
What mammal besides humans can carry Lacazia loboi? |
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Definition
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Term
What are the clinical symptoms of Lacazia loboi? |
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Definition
Polymorphic dermal lesions, most common are nodular keloid-like lesions, long dormancy period |
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Term
What intensely stains Lacazia loboi? |
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Definition
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Term
What is the treatment for Lacazia loboi? |
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Definition
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Term
What is the main organism that causes trichinosis? |
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Definition
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Term
Where does the adult form of T. spiralis live? |
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Definition
Duodenal and jejunal mucosa of flesh-eating mammals, infections form is present in striated muscles of carnivorous and omnivorous mammals |
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Term
What is the life cycle of T. spiralis? |
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Definition
1. Infection begins when meat contains encysted larvae is digested
2. Larvae leaves meat in small intestine and w/in 2 days develop into adult worms
3. Single fertilized female produces more than 1500 larvae in 1-3 months
4. Larvae move from the intestinal mucosa into the bloodstream and are carried in the circulation to various muscle sites throughout the body, where they coil in striated muscle fibers and become encysted
5. Larvae remain viable for many years and are infectious if ingested by a new animal host |
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Term
What muscles are most frequently involved w/T. spiralis? |
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Definition
extraocular muscles of the eye, the tongue, the deltoid, pectoral, intercostal muscles, the diaphragm, gastrocnemius |
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Term
What animals have the greatest prevalence of T. spiralis?
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Definition
Pigs, also polar bears and walruses |
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Term
At what point do you see symptoms from invasion of T. spiralis? |
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Definition
when 100 present, significant disease
1000 to 5000 is very serious, sometimes death |
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Term
What are the signs and symptoms of T. spiralis? |
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Definition
few larvae, mild flu-like syndrome
more extensive, persistent fever, GI distress, eosinophilia, muscle pain, periorbital edema
Splinter hemorrhages beneath nails cause by vasculitis from toxic secretions
Severe infecton and death results from myocarditis, encephalitis, pneumonitis, respiratory arrest
As larvae encyst in muscle, edema and inflammation occurs, calcification in 5-6 months |
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Term
What is the treatment for T. spiralis? |
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Definition
Primarily symptomatic
Mebendazole may halt production of new larvae
Steroids recommended for severe symptoms |
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Term
What are the organisms that cause Bancroft and Malayan filariasis respectively? |
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Definition
W. bancrofti and B. malayi |
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Term
What are the vectors of Bancroft and Malayan filariasis? |
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Definition
Anopheles, Aedes, and Culex mosquitoes |
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Term
What is the life cycle of W. bancrofti and B. malayi? |
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Definition
1. Larvae migrate from the location of bite to lymphatic system, primarily in arms, legs or groin, where growth adulthood occurs
2. 3 to 12 months after initial infection, adult male worm fertilizes the female, which produces sheathed larval microfilariae that find way into circulation
3. Microfilariae in blood is diagnostic for human disease and is infective for feeding mosquitoes
4. In mosquito, larvae moves through stomach and thoracic muscles in developmental stages and migrate to proboscis
5. In proboscis, become infective, third-stage larvae and transmitted by feeding mosquito
Adult form in humans can persist for 10 years |
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Term
Where does infection with W. bancrofti occur? |
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Definition
tropical and subtropical areas and is endemic in central Africa, along Mediterranean coast, in many parts of Asia
No animal reservoir has been identified |
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Term
Where does infection with B. malayi occur? |
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Definition
Malaysia, India, Thailand, Vietnam and parts of Asia
Animal reservoirs are cats and monkeys |
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Term
What are the clinical signs of W. bancrofti and B. malayi? |
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Definition
acute presentation arises from inflammatory response to presence of molting adolescent worms and dead or dying adults w/in lymphatic vessels, lymph nodes enlarge involving extremities, scrotum, testes
this may also lead to filarial elephantiasis |
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Term
What are some laboratory diagnoses of W. bancrofti and B. malayi? |
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Definition
Microfilariae in Giemsa-stained blood, buffy coat films, membrane-filtration technique w/saline, both have nocturnal and subperiodic periodicity which results in greater numbers at night, sheath |
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Term
What is the treatment of W. bancrofti and B. malayi? |
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Definition
Drug of choice is diethylcarbamazine, surgical therapy for lymphatic obstruction |
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Term
What is the life cycle of Onchocerca volvulus? |
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Definition
1. Infection occurs w/introduction of larvae through the skin during biting and feeding of the Simulium or blackfly vector
2. Larval worms migrate from skin to subcutaneous tissue and develop into adult male and female worms
3. Adults become encased in fibrous subcutaneous nodules w/in which they remain viable for as long as 15 yrs
4. Female worm, after fertilization by male, begins producing as many as 2000 nonsheathed microfilariae each day
4. Microfilariae exit capsule and migrate to skin, eyes, and other body tissues, are infective for feeding blackflies |
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Term
Where is Onchocerciasis and O. volvulus endemic? |
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Definition
Africa, especially in Congo basin and Volta River basin |
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Term
What is the main vector of O. volvulus? |
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Definition
Simulium damnosum, which breed in fast-flowing streams |
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Term
What is the common symptom of onchocerciasis? |
|
Definition
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Term
What are the clinical manifestations of O. volvulus due to? |
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Definition
Chronic inflammatory rxn to antigens to microfilariae |
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Term
What are the initial signs of O. volvulus? |
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Definition
fever, eosinophilia, urticaria, subcutaneous nodules, hanging groin |
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Term
What is the laboratory diagnosis for O. volvulus? |
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Definition
skin snip preparations from infrascapular or gluteal regions, incubated in saline, may also be seen in anterior chamber with aid of slit lamp in eye |
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Term
What is the treatment for O. volvulus? |
|
Definition
Surgical removal
Treatment w/ivermectin |
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