Systemic Infections Flashcards
(38 cards)
How do systemic infections begin?
starts in one part of the body and then spreads to other sites using cardiovascular and lymphatic system
- often starts in one that are well-vascularized/intimately connected to cvs system
- e.g., lungs, kidneys
Inflammation of the Heart - what is it called?
there are 3
inflammation of:
- endocardium = endocarditis (most common bacteria, can hold/host colonization and create biofilm); affects valves
- pericardium = pericarditis (viral)
- myocardium = myocarditis (most often viral)
Lymphatic systems - what can be affected?
there are 3
lymphadenopathy = swelling of lymph nodes (can only feel, not see)
lymphadenitis = inflammation of lymph nodes (can see and feel pathogen)
lymphangitis = inflammation of lymph vessels
What are some systemic viral infections?
- infectious mononucleosis
- burkitt’s lymphoma
- cytomegalovirus infections
- dengue virus
what are the systemic bacterial infections?
-systemic inflammatory response syndrome (SIRS) = medical emergency characterized by rapid HR, RR, abnormal wbc + fever
* bacteremia = bacteria in bldstream
* sepsis = infection of bldstream
* septicemia = pathogen replicates to high #s, overcomes innate immune system
* septic shock = catastrophic drop in BP d/t severe sepsis (superantigens/ PAMPS)
- plague
- lyme disease
- rocky mountain spotted fever
What are the bacterial infections of the heart?
- subacute bacterial endocarditis
- infectious endocarditis
- acute bacterial endocarditis
- prosthetic valve endocarditis
What is the criteria for sepsis?
= suspected or documented infection and an acute increase in =/> 2 sepsis related organ failure assessment (SOFA) points
what is the criteria for septic shock?
suspected or documented infection plus vasopressor therapy needed to maintain mean arterial pressure @ >/= 65 mmHg and serum lactate > 2.0 mmol/L despite adequate fluid resuscitation
what is the definition of sepsis?
life-threatening organ dysfunction caused by dysregulated host response to infection
what is the definition of septic shock?
subset of sepsis in which underlying circulatory and cellular/metabolic abnormalities lead to substantially incr mortiality risk
how do you calculate mean arterial pressure (MAP)?
[2(diastolic) + systemic]/ 3
SIRS vs SOFA criteria
SIRS: more sensitive for diagnosing sepsis (quicker)
SOFA: more accurate for predicting hospital mortality among pts with sepsis
What is the Hour-1 bundle?
= system that promotes physicians to act as quickly as possible to obtain bld cultures, administer broad spectrum abx, start appropriate fluid resuscitation, measure lactate, and begin vasopressors if clinically indicated
- for sepsis / septic shock
Infectious Mononucleosis: EBV
what family? How does it infect and replicate? incubation period?
- herpes virus family, human herpesvirus 4 (HHV4)
- virus infects and replicates in oral cavity, is shed in saliva –> latent
- oropharyngeal epithelium, tonsils, and salivary glands
- B-cells affected –> atypical appearance –> systemic spread
incubation period = 5 weeks
What are the main viral agents causing systemic infections in Canada?
- west nile virus (WNV): in canada since 2001, have varying epidemic intensities linked to climatic factors
- epstein-barr virus: significant cause of systemic infections, including infectious mononucleosis and associated cancers
- cytomegalovirus (CMV): commonly found in immunocompromised individuals and can cause severe systemic disease
- dengue virus: incr encounters among travelers returning to canada
Infectious Mononucleosis, EBV: S/S + Dx
S/S: fever, sore throat, fatigue, generalized lymphadenopathy & enlarged spleen + liver
- look @ wb count
dx: monospot test (heterophile antibodies) + serology
Cytomegalovirus infections
family? where is it shed? general info?
- herpes virus family, HHV-5 (dsDNA virus) –> episomes = latency
- asymptomatic (primary) or CMV-mononucleosis-like syndrome
- shed virus in body fluids (saliva + urine)
- cell-mediated immunity
1.
what cancers are associated with EBV?
hodgkin lymphoma
non-hodgkin lymphoma
- B-cell lymphoma
- burkitt lymphoma
Who faces a higher risk of CMV reactivation?
immunocompromised individuals
- fever, pneumonia, hepatitis, encephalitis
what transmission can CMV have?
vertical transmission
- transplacental (75%), most asymptomatic
- congenital cytomegalovirus infection (microcephaly, seizurse, petechial rash, moderate hepatosplenomegaly with jaundice)
Dengue hemorrhagic fever: how many serotypes? how is it transmitted? incubation period?
4 serotypes = can make 8 antibodies (IgM & IgG for all 4 serotypes)
- transmitted by female mosquitoes (Aedes aegypti and Aedes albopictus) = endemic in tropics
- incubation period = 4-10 days after bite
Dengue: S/S?
- high fever
- retro-orbital headache
- intense joint and muscle pain
- rash (MP or petechial)
- skin more fragile - microhemorrhagia
- “white islands in a sea of red,” small healthy skin but rash is massive
- can have asymptomatic dengue but still have antibodies
What are the 3 types of Dengue?
- without warning signs
- with warning signs
- severe dengue
labratory tests for dengue
- serology (IgM, IgG)
- RT-PCR for detecting viral RNA
- CBC shows low platelet count and elevated hematocrit
