May4 M1-Fever in Immune Compromised Hosts Flashcards
febrile neutropenia def
- fever >38.3 once or >38 twice with 1 hr interval
2. ANC < 500
organisms to consider in febneut
- gram- enteric rods (gut mucositis)
- gram+ cocci like CoNS and MSSA, MRSA. Also, pseudomonas (central line infection)
- candida (central line and gut), aspergillus (lungs)
- Strep pneumo, resp viruses, C.diff (usual org causing fever)
main cause of febneut in cancer chemo pts
- unexplained fever (39%)
- clinically defined infection (17%)
- microbiologically defined infections (44%)
- # 1 bacteremia with gram+ cocci*
- # 2 bacteremia with gram - bacilli*
cause of the unexplained fever in febneut patients
LPS and exotoxin shedding from gram- organisms inthe gut (can cross to blood bc barrier problem) but no invasion
(imp?) causes of fever in a NEWLY diagnosed cancer patient (no chemo yet)
- tumour or cancer fever
- community stuff (S pneumo, resp viruses)
febneut patient with no symptoms: how to approach
- think of bacteria from denuded gut
- think of community things (pneumonia, respiratory viruses)
- persistent fever even on broad spectrum Abx, think fungal (candida, aspergillus)
febneut approach in symptomatic patient:
- redness or painful IV = central line sepsis
- diarrhea: think C.diff
(imp) most common cause of bacteremia in cancer chemo patient
CoNS (staph epidermidis)
febneut approach in patient with symptoms of mucositis and shock
-gut bacteria
-pneumonia, resp viruses
-fungi
-CoNS
(all the previously said) and
STREP VIRIDANS (add this one if see these symptoms)
(imp?) organisms that must always be covered at least (as empiric Abx for the febneut)
- gut bacteria (including anaerobes)
- pseudomonas
- staph aureus
(imp?) organisms that must always be covered if there is presence of mucositis or shock (as empiric Abx for the febneut)
- gut bacteria (including anaerobes)
- pseudomonas
- staph aureus
- strep viridans
(imp?) organisms that we must worry about when choosing empiric Abx for febneut if we know or are worried about resistance
- MRSA
- VRE
- ESBL (extended spectrum beta lactamases, are gram- bacteria)
(EXAM) broad spectrum Abx required to cover gram- of gut, staph aureus and pseudomonas
-broad spectrum beta-lactams (meaning beta-lactam + bli, like Pip/Tazo)
-aminoglycosides IV
-vanco IV
(if oral therapy at home = ciproflaxin + clindamycin)
when give empiric antifungal tx in febneut
- NOT in beginning unless clinical evidence for FUNGAL infection
- only if fever persists >4 days in cancer pt for febneut
- *never stop Abx**
how to investigate for fungal infection in febneut when suspect it
- check where candida caused disease: 1. liver and spleen imaging 2. retinal exam 3. chest CT
- invasive pulmonary aspergillosis will be seen on chest CT
(imp?) best anti-fungal against aspergillosis in febneut pts
voriconazole
when to give empiric anti-viral tx in febneut
NOT in the beginning and usually never UNLESS
- characteristic rash of VZV, shingles or herpes
- severe resp illness (influenza)
3 phases of BMT
- phase 1: pre-engraftment (neutropenia, barrier breakdown, mucositis and CVC access)
- phase 2: post-engraftment (impaired cellular and humoral immunity. these cells recover in that order: NK, CD8 T. still restricted T cell repertoire
- phase 3: late phase (impaired cellular and humoral immunity. these cells recovering: B, CD4 T. repertoire diversifies.
(important) infections in phase 1 of BMT (bacteria, viruses, fungi)
- gram- rods (bacilli)
- gram+ organisms
- HSV
- resp and enteric viruses
- aspergillus
- candida
(important) infections in phase 2 of BMT (bacteria, viruses, fungi)
-reactivation of latent viruses and organisms (CMV, EBV, HSV, VZV, TB)
-aspergillosis
(chronic viruses back. gut healing so less gram-)
(important) infections in phase 3 of BMT (bacteria, viruses, fungi)
- encapsulated bacteria (prob now bc immune system never back 100%)
- VZV
- aspergillus
- pneumocystis
- opportunistic pathogens
(important) what organisms to cover in febneut
-gut organisms (including anaerobes)
-pseudomonas aeruginosa
-staph aureus
-respiratory
organisms
(beta-lactam+bli comination AND aminoglycoside)
(important) when to use big things like vanco in febneut
ONLY if:
- shock
- mucositis
- line sepsis
- known MRSA
- known bacteremia with g+ cocci
infections in people with humoral immunity dysfunction
- Strep pneumo
- H. influenza
- mycoplasma spp
- moraxella
- recurrent sinopulmonary infections with community organisms*
function of humoral immunity against infections
- secretory Abs in mouth and resp tract
- not functioning = sinusitis, recurrent ear infection, pneumonias
cellular immunity dysfunction: infections you get
- IC organisms: salmonella, listeria, mycobacterium spp
- fungi (inc. pneumocystis), viruses, parasites (inc. toxoplasma)
cellular immunity dysfunction can happen how
- SCID (no lymphoid tissue, no tonsils)
- HIV
- large amount systemic CSs
complement immunity dysfunction = get what recurrent infection
Neisseria meningitidis
prob in MAC
infections in neutropenic pts (not due to chemo)
community organisms
- S. pneumo
- S. aureus
- Mycoplasma spp
- resp viruses
- N meningitidis
- UTIs
infection in Jobe’s syndrome
staph aureus (skin disease boils and all that)
infections in CGD (chronic granulomatous disease, macrophages can’t do oxidative burst after phagocytosis)
catalase + organisms
- S aureus
- Aspergillus
infections in asplenic or splenic dysfct people
encapsulated organisms (S pneumo, H influenza, N meningitidis) and also salmonella spp if have sickle cell
management of fever in babies <3 months
medical emergency (especially if under 6 months of age)
organisms babies can get infected with because of maternal stool and vaginal organisms and maternal organisms
- enteric gram- rods
- GBS
- listeria
- S aureus (MSSA, MRSA)
- GAS
- HSV (sepsis, encephalitis)
organisms premature babies can be infected
candida albicans and all the previous (-enteric gram- rods
- GBS
- listeria
- S aureus (MSSA, MRSA)
- GAS
- HSV (sepsis, encephalitis))
approach to febrile neonates <1 months
- presume serious bacterial infection
- full septic workup (blood, urine cultures), LP culture
- empiric Abx covering gram-, listeria, GBS
- CXR, nasopharyngeal viral studies, stool culture
- meningitis doses of ampicillin and cefotaxime if suspected
acyclovir to febrile neonates: yes or no
- not in current practice
- but delaying it increases mortality…
tx of febrile neonates <1 month
- ampicillin IV
- gentamicin IV
- cefotaxime IV for meningitis (3rd gen cephalosporin)
tx of febrile neonates between 1-3 months of age
-option 1: ampicillin IV
+ gentamicin IV
-option 2: -ampicillin IV + cefotaxime IV for meningitis (3rd gen cephalosporin)
