Micro: opportunistic infections (didnt know it was done already) Flashcards
What is a compromised host?
greater than 1 defect in the bodies natural defense
can be defect with innate or adaptive
they have an increased likelihood of suffereing from severe, life threatening infections
In general, what are primary deficiencies?
inherited, congenital
In general, how do secondary deficiencies arise?
d/t underlying diseases or from a treatment from disease
Give examples of primary innate immunodeficiencies?
complement and phagocytic deficiency
something that’s wrong with the body’s immune system
Give examples of secondary innate immunodeficiencies?
Burns- Damage to skin –> 1st barrier to infection and vascular tissue
Trauma/Surgery- organism goes into blood via wound, GI –> sepsis and shock
Obstruction- urine flow via catheter –> UTI , ciliary action, peristalsis
from another source
Give examples of primary adaptive immunodeficiencies?
T-cell, B-cell, and combined immunodeficiencies
These usually manifest as peds diseases
Give examples of secondary adaptive immunodeficiencies?
Malnutriition, AIDS, cancer, transplantation, stress, pregnancy
All these are immunosuppression
What deficiency is C3 and what is it?
A complement deficiency
Affects all immune pathways
C3 is missing –> C3b missing –> no opsonization –> can’t remove bacteria
What are some bacteria that are involved in C3 complement deficiency?
Enterobacteriaceae
Gram positive cocci
Haemophilus influenzae
Pseudomonas aeruginosa
MAC (membrane attack complex), which complements are involved?
C5-9
which cause defects in cell surfaces –> cell death
What is the most common recurrent infection with MAC deficiency?
recurrent bacterial meningitis from N. meningitidis
Chronic granulomatous disease (CGD) occurs with which deficiency and what is it?
Phagocytic deficiency
NADPH oxidase is deficient which leads to a recurrent infection with catalase positive bacteria
What are some bacteria assocaited with CGD?
Enterobacteriaceae Staphyococcus Pseudomonas aeruginosa Aspergillus Mucor (Rhizopus)
Leukocyte adhesion deficiency (LAD) occurs with which deficiency and what is it?
Phagocytic deficiency
A defect in LFA-1 integrin protein which allows neutrophils to make their way out of the blood stream by adhering to receptors on the apical surface of endothelial cells in the infected areas –> recurrent infections
No pus, no abscess develops
What are some bacteria assocaited with LAD?
Gram pos. cocci, Gram neg. rods
Strep pneumoniae S. aureus S. epidermidis Klebsiella pneumoniae Enterobacter cloacae Pseudomonas aeruginosa Acinetobacter baumanii
Most common organism associated with burn wound infections?
P. aeruginosa (50%) and S. aureus (50%)
What are other types of infections associated with burn wound infections?
Bacterial infection : coag neg. staph, enterobacteriaceae
Fungal infection: candida (localized), Mucor (disseminated), Aspergillus
Viral infections: herpes, uncommon
What are other types of infections associated with burn wound infections?
Bacterial infection : coag neg. staph, enterobacteriaceae
Fungal infection: candida (localized), Mucor (disseminated), Aspergillus
Viral infections: herpes, uncommon
In obstruction, what constitutes 40% of nosocomial infections?
catheters –> always check for UTI
common source of bacteremia
In obstruction, what constitutes 40% of nosocomial infections?
catheters –> always check for UTI
common source of bacteremia
Most common organism associated with obstruction infections?
E.coli
its teh most common community and HAI
Most common organism associated with obstruction infections?
E.coli
its teh most common community and HAI
T-cell Primary adaptive immunodeficiencies?
DiGeorges*
Viruses, fungal pathogens
What are other organisms associated with Obstruction infection?
mostly nosocomial: -K.pneumoniae (drug resistant) Proteus -Pseudomonas (drug resistant yeast Enterococci S.epidermidis
B-cell Primary adaptive immunodeficiencies?
X-linked agammaglobulinemia - most common
-No B cells in the periphery
-S.pneumoniae, H.influenzae
Hyper-IgM syndrome, selective IgA deficiency
-Bacterial infections at mucosal surfaces
Non-enveloped viruses (B19, norovirus)
Malnutrition affects T-cell or B-cell immunity?
BOTH, t-cell and b-cell immunity
T-cell Primary adaptive immunodeficiencies?
DiGeorges
Viruses, fungal pathogens
Combined immunodeficiency Primary adaptive immunodeficiencies?
SCID – susceptible to just about anything
Bacteria, viruses, fungi, parasites
Malnutrition is..?
secondary adaptive immunodeficiency
an imbalance supply of nutrients and energy and the body’s demand to ensure growth, maintenance, and specific function
Malnutrition affects which immunity?
BOTH, t-cell and b-cell immunity
Which patients are HIV mostly seen in?
AIDS, cancer, transplant pt
Persistent, generalized is what stage of HIV?
asymptomatic infection
what is the algorithm for HIV symptomatic?
lymphadenopathy→symptomatic→AIDS defining conditions
AIDS: T-cell count is <200
what are the clinical stages of HIV?
acute, asymptomatic, symptomatic, AIDS
What happens in acute stage?
the p24 levels peak early BUT also drops quickly
that’s why the immune system is able to keep the virus “in check” at first, then it goes all ape shit
What happens in asymptomatic stage?
CD4 levels decrease
No trace of p24 protein
Ab to env Ag begin to rise slowly
Ab to p24 rise and plateaus
What happens in symptomatic stage?
CD4 levels decrease even more
Increase of p24 protein
Ab to env Ag plateaus
Ab to p24 decrease with CD4 levels
What happens in AIDS?
T-cell count <200
what are the most common pulmonary infections for HIV pt with >= 200 cell count?
(There are more on the chart she gave us but I wrote the ones she read off )
S.pneumoniae,
H.influenzae,
Mycobacterium tuberculosis
what are the most common pulmonary infections for HIV pt with 50-200 cell count?
Pneumocystis jiroveci Cryptococcus, Aspergillus, Mycobacterium kansasii \+ S.pneumoniae, H.influenzae, Mycobacterium tuberculosis
what are the most common pulmonary infections for HIV pt with <50 cell count?
CMV \+ Pneumocystis jiroveci Cryptococcus, Aspergillus, Mycobacterium kansasii \+ S.pneumoniae, H.influenzae, Mycobacterium tuberculosis
What is special about Ab to env Ag?
susceptible to ANTIGENIC DRIFT
so immune system needs to always keep up
what are the most common pulmonary infections for HIV pt with >= 200 cell count?
(There are more on the chart she gave us but I wrote the ones she read off )
S.pneumoniae,
H.influenzae,
Mycobacterium tuberculosis
what are the most common GI infections for HIV pt with <50 cell count?
HSV CMV M. avium intracellulare \+ Cyrptosporiudium Isospora Cyclospora \+ Candida oral hairy leukoplakia - EBV HHV-8 C.difficile
what are the most common pulmonary infections for HIV pt with >= 200 cell count?
CMV \+ Pneumocystis jiroveci Cryptococcus, Aspergillus, Mycobacterium kansasii \+ S.pneumoniae, H.influenzae, Mycobacterium tuberculosis
what are the most common GI infections for HIV pt with >= 200 cell count?
(There are more on the chart she gave us but I wrote the ones she read off )
Candida
oral hairy leukoplakia - EBV
HHV-8
C.difficile
what are the most common GI infections for HIV pt with 50-200 cell count?
Classic parasites: -Cyrptosporiudium -Isospora -Cyclospora \+ Candida oral hairy leukoplakia - EBV HHV-8 C.difficile
what are the most common GI infections for HIV pt with <50 cell count?
HSV CMV M. avium intracellulare \+ Cyrptosporiudium Isospora Cyclospora \+ Candida oral hairy leukoplakia - EBV HHV-8 C.difficile
what are the most common cutaneous infections for HIV pt with > 500 cell count?
S. aureus
S.pyogenes
Tineas
what are the most common cutaneous infections for HIV pt with 250-500 cell count?
VZV (zoster)
HSV
what are the most common cutaneous infections for HIV pt with < 250 cell count?
Bartonella HHV-8 CMV Leishmania Molluscum contagiosum Candida Scabies disseminated fungal infections
What are the two most common pathogens associated with CNS issues? (for HIV pt)
Cryptococcus neoformans (<200 cells/mm3)
The other CNS infections?
TB Syphillis Listeria HIV systemic fungi
Which BACTERIAL infection is generally seen in the first month after transplant?
P. aeruginosa, S. marcescens and E.cloacae
MRSA, VRE
Leginella, Nocardiosis
Basically gram - rods and gram + cocci
What is generally seen in the first month of post transplantation?
nosocomial infections most common viral is HSV seen within first weeks surgery related UTI immunosuppression exacerbates
What is seen 2-6 months post transplantation?
immunosuppression
What is seen after 6 months post transplantation?
Community acquired infections
UTI
VZV reactivation
things seen after discharged from hospital
Which bacterial infection is generally seen in the first month after transplant?
P. aeruginosa, S. marcescens and E.cloacae
MRSA, VRE
Leginella, Nocardiosis
Basically gram - rods and gram + cocci
What are the other FUNGAL infections? post transplant
Cryptococcus
-For HIV mostly
Coccidiodes
Histoplasmosis
What s/s do post transplant CMV pt get?
interstitial pneumonitis
AIDS pt also get retinitis
What are the other viral infections post transplant?
VZV, HSV, EBV - mono
BK virus - renal disease
Influ A and B, adenovirus - respiratory infections
What are the 2 most common FUNGAL infections post transplant?
Candida
Aspergillus –>very bad news for IC pt.
Acid fast oocysts, parasites
small circular acid fasts –> cryptosporia parvum
huge, elliptical acid fasts –> isosporia
isospora clincally looks like giardia b/c it causes malabsorption
Owl’s Eye?
CMV
Dented helmets, condoms?
PCP (pneumocystis pneumonia)
aka PJP
HIV pt with PERSISTENT diarrhea
ALWAYS cryptosporia!!
Persistent diarrhea –> Parasite
Acid fast oocysts, parasites
small circular acid fasts –> cryptosporia parvum
huge, elliptical acid fasts –> isosporia
isospora clincally looks like giardia b/c it causes malabsorption
HIV pt, excessive weight loss, CD4 count is 75, Acid fast bacilli
M. avium intracellulae
HIV, severe headache
CNS issues:
Toxoplasma –> “ring enhancing” lesions
Crytococcus neoformans –> encapsulating yeast –> leading form of meningitis in AIDS pt
What do you see in pt with Mucor
IC pt with respiratory infection
Labs: ketoacidosis diabetic and sinusitis
90 degrees, nonseptae hyphae
sickle cell anemia, tachy, hypotension, fever
Labs: leukocytosis with left shift
encapsulated gram + cocci
blood agar - alpha hemolysis
some kind of sepsis is going on
- encapsulated bacteria
S. pneumo
HIV, multi-colored lesions
Kaposi = HHV-8 (which is most common)
Bacillary angiomatosis = Bartonella (B. henselae)
IC pt with respiratory infection
Labs: neutropenia
sputum negative for bacterial growth
septae at 45 degrees
Aspergillosis
IC pt with respiratory infection
Labs: ketoacidosis diabetic and sinusitis
90 degrees, nonseptae hyphae
Mucor