L32- Multi-system Infections III Flashcards
list the common microbial multi-system infections contracted via inhalation, urine, and ingestion
Inhalation: Tularemia, F. tularensis (bacteria)
Urine contact: Leptospira, L. interrogans (parasite)
Ingestion:
- Brucellosis, B. spp. (bacteria)
- Echinococcosis, E. spp (parasite)
Tularemia:
- (1) pathogen
- (2) route of transmission
- (3) geographic predominance
- (4) season predominance
- (5) occupational predominance
1- Francisella tularensis
2- inhalation via animals (usually dead) — also ingestion or injection (skin, eye, mouth, lungs)
3- northern hemisphere
4- late spring - summer
5- hunting, trapping, lab workers, farm workers (winter mos)
describe the many microbial features of Francisella tularensis
- Gram- short rod
- strict aerobe in environment; facultative aerobe in cells
- evidence on intracellular survival in macrophages
- nutritionally fastidious
After entry of F. tularensis, it spreads to (1) and then will spread to (2). It primarily infects (3) cells and undergoes (4) within (3). (5) are the major target organs.
1- regional LNs
2- multiple organs via lymph or blood
3- macrophages after phagocytosis
4- LNs, lungs, liver, kidneys
F. tularensis:
- (1) can develop only from inhalation
- (2) can develop only from injection
1- hemorrhagic inflammation of airways –> bronchopneumonia
2- granulomatous inflammation, ulcerated lesion at injection site
F. Tularensis:
- (1) incubation period before (2) symptoms (common to all syndrome types)
- (3) list the syndrome, based on transmission – indicate syndrome with highest mortality
- (4) mortality rate
1- 2-5 days
2- undulant fever, chills, malaise (pulse-Temp. dissociation)
3:
- Inhalation: **Pneumonic- highest mortality
- Injection: ulcero-glandular (lowest), glandular, oculoglandular
- Ingestion: oropharyngeal, typhoidal
4- 5-30% depends on type
Ulceroglandular Tularemia:
- (1) transmission
- spreads via (2)
- (3) presentation
1- injection: scratch, abrasion
2- lymphatics
3- painful regional lymphadenopathy, ulcerated skin lesion
Glandular Tularemia:
- (1) transmission
- (2) presentation
1- injection
2- tender lymphadenopathy w/o evidence of local cutaneous lesions
Oculoglandular Tularemia:
- (1) transmission
- (2) presentation
1- injection: enters conjunctiva via rubbing eyes (contact with contaminated fluids)
2- unilateral, purulent conjunctivitis, corneal ulceration, lymphadenopathy
Oropharyngeal Tularemia:
- (1) transmission
- (2) presentation
1- ingestion: undercooked meat, contaminated water
2- stomatitis (oral/labial inflammation), exudative pharyngitis / tonsillitis, abdominal pain, lymphadenopathy, GI bleed, n/v
Pneumonic Tularemia, aka (1):
- (2) transmission
- (3) presentation
1- primary tularemia pneumonia
2- inhalation
3- dry cough, dyspnea, pleuritic-type chest pain, hilar adenopathy, bloody pleural effusion, ARDs
Typhoidal Tularemia:
- (1) transmission
- (2) presentation
1- ingestion (most severe)
2- bacteremia; secondary pneumonitis
Note- difficult to Dx b/c no ulcers, lymphadenopathy
Tularemia / F. tularensis Dx- indicate primary and alternative methods
-**direct IFA
- serodiagnosis: titers x2
- PCR, real time-PCR
Note- culture is difficult and risky for personnel
(1) is the common infection caused by contact with animal urine / soil, and possess the following microbial characteristics, (2). It is commonly found in (3) and requires (4) transmission.
Leptospirosis- L. interrogans
- thin, tightly coiled spirochetes
- motile- 2 periplasmic flagella
- obligate aerobes
- sensitive to heat, drying, chemicals
- Found in soil (alkaline environment) for 1-2 wks
- Enters penetrating breaks in skin / mucous membranes
Leptospira interrogans:
- multiplies in (1) cells, leading to (2) clinical syndrome
- early stages, parasite is found in (3)
- late stages, parasite is found in (4)
- (5) other DDx that it is often confused with
1- endothelium of small BVs
2- Weil Disease
3- CSF, blood
4- urine
5- Dengue
Leptospirosis:
- infection occurs through (1) transmission
- (2) initial Sxs, include timeline
- (3) 2nd phase Sxs, include timeline
1- enters thru skin abrasions / conjunctiva
2- 1-2wks: acute febrile illness
3- Weil disease: liver / kidney disease- hemorrhage, necrosis, organ dysfunction
list the types of Leptospirosis and associated symptoms
Primary:
- Bacteremic: flu-like, v/d, conjunctival suffusion, calf and lumbar pain
- Meningitic: like viral meningitis (nuchal rigidity, HA, n/v)
Secondary:
- Icteric: fever, hemorrhage, hepatic / renal impairment
- Pulmonary: ARDS
______ is the main method of diagnosis Leptospirosis
MAT- microscopic agglutination test (Ab detection / serology)
Of the common ingested microbes causing multi-system infections, (1) is related to unpasteurized foods and (2) is related to contaminated foods
1- Brucella spp.
2- Echinococcus
Brucellosis:
- (1) list the bacteria species
- (2) describe its basic features
- (3) methods of transmission
1- B. abortus, B. melitensis, B. suis, B. canis
2:
- Gram- coccobaccilli, aerobic
- small, non-motile, non-encapsulated
- requires complex growth media
3- *ingestion, direct contact (lab), inhalation
List the Brucella spp. causing Brucellosis, include:
- rank by pathogenicity
- geographic area
- natural host
B. melitensis: highest pathogenicity
- everywhere (including USA) besides Africa
- goats, sheep, camels
B. suis: high pathogenicity
-South Asia, pigs (swine)
B. abortus: moderate
- Africa, Asia, S. Amer.
- cattle (a-bovine)
B. canis: moderate
-dogs (canine)
describe the colonies Brucella spp. form in the body and how it relates to pathogenesis
Smooth: O chain/Ag of smooth LPS = virulence marker, indicates more serious disease (weak endotoxin)
Rough: switch is associated with dec virulence of bacteria and disease severity
In the body, Brucella spp. bacterium infect (1) cells which is then transferred to (2) cells, explain. Then, it travels to (3) organs before reaching (4) where it secreted proteins in order to form (5).
1- intracellular parasite of RES
2- macrophages via phagocytosis (inhibits lysosome-phagosome fusion)
3- spleen, liver, BM
4- LNs (via PMNs), kidneys
5- granuloma
______ bacteria infects humans in USA who consume unpasteurized milk / dairy products
B. melitensis
rank the Brucella spp. in order of most serious disease / infection:
- acute disease occurs in __%
- incubation period = __
- Mild: B. abortus, B. canis
- Destructive Lesions: B. suis
- Severe: B. melitensis
50% experience acute disease
1-3 wk incubation period
Brucellosis, Acute infection:
- (1) incubation period
- (2) are the common presenting symptoms
- (3) are the other symptoms
1- 7-21 days
2- undulent high fever (drenching sweat), rigors, lethargy, HA, myalgia, scrotal pain; lymphadenopathy, splenomegaly
3- delirium, abdominal pain, constipation
describe the features of chronic brucellosis
-chronic episodes of nocturnal fever for mos - yrs
- weight loss
- glandular or hepatic symptoms
- sacroillitis
- depression
______ is the main method of diagnosis Brucellosis
serology- titers
-may also take blood or BM samples for culture
E. granulosus microbial features
Parasite:
- hermaphrodites
- adults: 3-6mm long taking 32-80 days to develop
E. granulosus is transmitted to humans via (1) contact while the (2) form. (2) are in (3) form- explain and the develop into (4) form, explain.
1- feces with larvae in contaminated products, ingestion
2- larvae
3- Hydatid Cyst (lungs, liver): 5-20cm containing daughter cysts
4- Unilocular Cyst: brood capsule and daughter cysts disintegrate into mother cyst
______ are the causes of Echinococcosis
E. granulosus
E. multilocularis
describe the clinical features of E. granulosus infection- include incubation period, sxs, complications
-silent up to 20 yrs
Sxs based on location of cysts:
- Liver: abdominal pain, hepatomegaly, cirrhosis, biliary obstruction
- Lung: chest pain, cough, hemoptysis
- possibly brain, bones, kidneys, heart
Rupture of cysts (possibly trauma) –> massive Ag release –> fever, urticaria, eosinophilia + Anaphylactic shock
E. multilocularis microbial features
Parasite:
- hermaphrodites
- adults: 1.2-3.7mm long taking
- larval growth limited to liver indefinitely –> invades surrounding tissue
After ingestion of E. multilocularis, egg undergoes (1- include location), to release (2). (2) will penetrate GIT walls and travel to (3). (2) will then undergo (4) progression in (3) locations.
1- egg hatches in SI
2- oncosphere
3- liver, lungs via blood
4- cyst development –> protoscolices + daughter cysts in the interior
Echinococcosis:
- (1) mechanical Sx
- (2) immune Sx
- (3) mechanism to avoid immune response
1- tissue damage –> pressure atrophy
2- damage via anaphylactic shock
3- conceals Ag sites via coating of host molecules (host cells block Ags)
describe clinical features of E, multilocularis infection
- slow growing liver tumor => abdominal pain, biliary obstruction
- occasional metastasis lesions to lungs, brain
describe diagnosis of Echinococcosis
- CT, MRI. X-Ray for cysts
- serology for Abs
