Immunocompromise Flashcards
what does being immunocompromised mean
state of health where actuarial risk of infection is increased
what are 3 person centered aspects that affect the immune system
- macrobiome
- microbiome
- Host
5 primary defences that affect the microbiome
- flow
- gravity and motility
- skin and mucosal integrity
- pH and chemical factors
- normal flora
what happens if alter flow
predisposes to infection - usually from own microbiome
3 examples of low flow
- endobroncial tumor
- men with BPH get bladder infections
- women with lymphedema for breast cancer get cellulitis
what are diffs. between bacteria in mouth vs. gut
mouth - gram-pos. and araerobes
gut - gram negs
2 adv of gravity
- no butt to mouth transfer
2. shower and clean effectively
problems assoc. with bedrest
- pneumonia is often due to fecal organisms
2. skin wounds infected with fecal organisms
2 examples of altered pH
- intubated patients treated with gastric acid supressants - more pneumonia
- patients with dry mouth at risk for more cavities and caires
3 functions of skin
- barrier
- has immune cells within it
- has mucosae that secrete mucus and works with cilia to move stuff out
examples of altered skin/mucosa
- bed sores
- surg. site infections
- burn wounds
- IV drug use
- febrile neutropenia
what is mech. of bed sores
pressure on “dependent’ areas causes ischemia and get necrosis - flora get in
what is burn mortality related to (2)
- age
2. body surgface burned
what happens in IV drug use
- poke bacteria into system from skin (staph)
- local abscess, endocariditis, celulitis
2 most common causes of altered normal flora
- antibiotics
2. poor infection control
what is C. diff
anaerobic gram pos. bacteria that resisits all but a few antibiotics
ho do people get C. diff
2% already have it or in hospital - shows up once normal flora reduced with antibiotics
c.diff Sx
- diarrhea, colitis,
what is mucosal candidiasis
normal to have yeast, but held in control normally,
- alteration leads to an overgrowth
- vagina, penis, throat (thrush - usually with HIV)
what is candidemia
blood infection of candida
2 risk factors for candidemia
- broad spectrum antibiotics
2. indwelling IV cath.
what is problem with prosthetic devices
get infected with staph causing a biofilm on device
what is problem with PICC lines
pulls infection in from skin and often goes to heart
what is diff. about infection for intra vs. extravascular devices
intra can remain at risk through contact with blood, whereas extra tend to only get infected during insertion
2 types of complement deficiency
- congenital - rare
2. aquired - acute (serious insult) or chroni (autoimmune)
what is most common and important complement deficiney
late complement (c5-9)
what is late complement deficency
- increased risk of meningococcal infection (nesseria)
- later onset of meningococcus (17 vs. 5)
- 50% are recurrent
- 1/10 mortality
how to help late complement def.
vaccines for meningococcal
what are 2 possible problems with neutrophils
- neutropenia - not enough
2. defect - don’t work right
possible ways of neutropenia
- inherited
- drug induced
- chemo
- autoimmune
4 possible neutrophil dysfunctions
- adhesion defects
- chemotactic defects
- opsinic
- intracellular killing
complication diffs. between neutropenia and defects
penia - sepsis
defects - local infections
what can complicate neutropenia
lack of primary defence systems
primary defences that are down in chemo-induced neutropenia - febrile neutro
- feel sick and in bed -
- venous cath - skin organisms
- mucotitis - GI barriers disrupted
- previous/prophylaxis antibiotics - fungi later on
things in timeline in febrile neutropenia
- mucosistis - 1 week
- fever - 1 week
- venous cath infection - 3 weeks
- lung infections - after venous cath
what is main clue to lung infection
fever- rest is subtle
2 consequences of neutrophil recovery
- asymptomatic pulm. infiltrates
2. hepatosplenic candidiasis
why do neutrophil things happen
actually fixing after an infection was already there
3 things that make hospitalization a state of immunocompromise
- antibiotics
- procedures
- contact with other sicko and lack of hand washing
what does adaptive immune system protect against
exogenous (macrobiome)
- viruses, bacteria, fungi, parasites
3 things Ig protect against
- resp tract from pneumococcal
- Gi from giardia, campylobacter
- skin from strep
what are types of Ig deficiencies (2)
- hypogammaimmunoglobunemia - all Ig low - more common
2. dysgamma…. - some Ig low
3 aquired causes of Ig def.
- nephrotic synd. - loss
- malabsorbtions - GI
- CLL
what is infection risk for cirrosis
spontaneous bacterial peritonitis - portal hypertension leads to backup as opposed to without, where don’t get leak out
what happens in CLL
- cell mediated immunocompromise
- sinus, resp, infection - incapulated organisms
what is immune function of spleen
clears encapsulated bacteria
what is risk for asplenia
overwhelming post-splenectomy infeciton (OPSI)
group at risk in OPSI
children
infection in OPSI
pneumoniae and meningo - vaccinate to prevent
4 main comorbids with HIV
- virus
- bact
- fungi
- protozoa
viruses with HIV
- reactivation with previous virus
- severe or community aquires -hepC, flu
bact. with HIV
mycobacteria -TB
fungi with HIV
- mucosal condidiasis
2. other
protozoa with HIV
- toxoplasma
- intestinal protozoa
3 sources of stem cell transplants (HSCT)
- autologous -self
- allogenic - matched donor
- syngenic - identical twin donor
what must be done before HSCT
conditioning - chemo and/or radiation
consequences of conditioning (4)
- transient neutropenia
- qualitative defects in phago
- major defects on humoral and cellular immunity
- mucusitis - causes gut leakage
what happens if donor lymphocytes not HLA matched
graft-vs. host disease
what happens in GVHD
- conditioning causes leakage of gut bacteria
- microbe activate effector cells
- dendritic cells with Ag go to lymph
- proliferation of donor Tcekk
- inflammation and attack other organs
what is given to deal with mucusitis in GVHD
- venous cath. for IV meds
- TPN
- supportive blood products
what happens d30-100 post graft
herpes viruses very important
what happens d100+
- generally out of the woods
- if cell mediated def. - viruses
- if humoral mediated def. - encapsulated bact
what are polyoma viruses
DNA viruses with latency aquired in childhood
what is BK virus
normally held in check but with HSCT can get renal graft failure (BK neuropathy)
3 HSCT prevention strategies
- prophylaxis
- pre-emptive treatment
- minimize exposure
what is CMV
cytoalomegalovirus - 8-90% of adults have -causes serious illness and hard to treat
when do HSCT get CMV
if the recipient has no CMV-ABs but the donor has CMV
what is frequent complication of lung transplant
pneumonia - hosts own flora
what is cause of lymphoproliferative disorder
infection with EB virus (immortalizes B-cells)
