Infectious DIsease Flashcards
Infective Endocarditis
- infection of the endocardium
- commonly affects heart valves, esp mitral valve
Risk factors for infective endocarditis
- Rheumatic, Congenital or Valvular Disease
- Prosthetic heart valves
- IV drug use
- Immunosuppression
Most common causative agent in infective endocarditis
S. aureus
- responsible for > 80% of acute bacterial endocarditis in pts with hx of IV drug use
Main causative agents in infective endocarditis
- S. aureus
- Viridans streptoccocci
- Coagualse negative Staphylococcus
- Streptococcus bovus
- Candida and Aspergillus
Viridans strep in infectious endocarditis
- most common pathogen for left-sided subacute bacterial endocarditis and following dental procedurs in native valves
Coagulase negative streptococcus in infectious endocarditis
- most common infecting organism in prosthetic valves
Streptococus bovis endocarditis
S. bovis endocarditis associated with co-existing GI malignancy
Candida and Aspergillus endocarditis
account for most cases of fungal endocarditis
- predisposing factors are: long-term IV catheters, malignancy, AIDS, organ transplant, and IV drug use
Pt presents w/ fever and new / change inmurmur. Likely diagnosis?
Endocarditis
Complications of endocarditis
JR = NO FAME Janeway lesions (flat and painless) Roth spots in eyes Nail-bed (splinter) hemorrhage Osler's nodes (raised and painful) Fever Anemia Murmur Emboli to lung or brain
Endocarditis: Hx adnd PE
- Constitutional sx (fever/FUO, weight loss, fatigue)
- exam reveals heart murmur (MV > AV) in non-IV drug users; right sided murmur in IV drug users (tricuspid > MV > AV)
- immune phenomena (e.g. splinter hemorrhages, Roth spots)
Diagnosis of Endocarditis
- Duke’s criteria
- 2 major, 1 major + 3 minor, 5 minor
- CBC with leukocytosis and left shift; incr ESR and CRP
Best initial test for endocarditi
- Blood cultures
- ## TTE
Duke’s Major Criteria for Endocarditis
- At least 2 separate positive blood cx for a typical organism, persistent bacteremia w/ any organism or a single culture of Coxiella
- Evidence of endocardial involvement (via TTE/TEE) or new murmur
Duke’s Minor Criteria
- predisposing factors
- Fever > 38.3
- Vascular phenomena: septic emboli, septic infarcts, mycotic aneurysm, Janeway lesions
- Immune phenomena: GN, Osler’s nodes, Roth’s spts,
- Microbiological evidence that doesn’t meet major criteria
Tx of infective endocarditis
Best empiric treatment is vancomycin and gentamycin
- narrow abx course wherever appropriate
Tx of Viridans Strep endocarditis
- Ceftriaxone for 4 weeks
Tx of S. aureus (MSSA)
Oxacilln, nafcillin, or cefazolin
Tx of fungal endocarditis (candida or aspergillus)
Amphotericin and valve replacement
Tx of staph epidermidis or resistant Staph endocarditis
Vancomycin
Tx of Enterococi endocarditis
Ampicillin and gentamicin
Indications for surgery in patient with endocarditis
- CHF or ruptured valve or chordae tendinae
- Prosthetic valves
- Fungal endocarditis
- Abscess
- AV block
- Recurrent emboli while on abx
Causative organisms in culture negative endocarditis
HACEK (Haemophlus parainfluenzae, Actinobacillus, Cardiobacterum, Eikenella, Kingella)
Coxiella burnetti
Brucella
Bartonella
Most common causes of culture negative endocarditis
Coxiella
Bartonella
Tx of HACEK group endocarditis
Ceftriaxone
Prophylaxis indications of endocarditis
- Significant cardiac defect (e.g prostetic
HIV
retrovirus that targets and destroys CD4 T cells
- infection characterized by high rate of viral replication that leads to progressive decline in CD4 count
CD4 count
- indicates degree of immunosuppression
- guides therapy and prophylaxis and helps determine prognosis
Viral load
may predict the rate of disease progression
- provides predictions for treatment and gauges response to ARTs
HIV: Hx and PE
- acute HIV, pts are often asymptomatic but patients may also present with mononucleosis-like or flu-like symptoms (e.g. fever, lymphadenitis, maculopapular rash)
- HIV may present later as night sweats, weight loss, thrush, recurrent infxns or opportunic infxns
Diagnosis of HIV
ELISA test (detects serum antibodies) then Western blot as confirmatory tests
Baseline eval for HIV should incle:
HIV RNA PCR (viral load) CD4 count PPD skin tests Pap smear Mental status exam VDRL/RPR serologies for CMV
Treatment for HIV
Initiate ART:
- symptomatic patients (those with AIDS defining illness no matter CD4 count)
- Patients with CD4 count < 350
- Pregnant patients
- Those with HIV specific conditions (e.g. HIV associated nephropathy, neurocognitive deficits)
Initial regimen for HIV
2 nucleoside reverse transcriptase inhibitors (NRTIs) plus 1 nonnucleoside reverse transcriptase inhibitor
– most import is select multiple meds (usually 3) to achieve durable treatment response and limit resistance
Goal of HIV therapy
Limit viral suppression < 50 copies
- after therapy is started CD4 count should be monitored monthly until suppression is achieved and every 3-6 months afterward
HIV + with CD4 300 - 500
Baceterial infections TB Herpes Simplex Herpes Zoster Vaginal candidiasis Hairy leukoplakia Kaposi's sarcoma
HIV + with 75 - 175
Pneumocytosis Toxoplasmosis Cryptococcus Coccidiomycosis Cryptosporidoios
HIV < 50
Disseminated MAC infection
Histoplasmosis
CMV retinitis
CNS lymphoma
Pregnant HIV + patient is not on ARVs at time of delivery, she should be treated with what meds?
Intrapaerum zidovudine
- infants should recieve AZT for 6 weeks after birth
Which is only live vaccine that should be given to HIV patients?
MMR
P jiroveci pneumonia (PCP pneumonia)
- prophylaxis indicated at CD4 < 200
prior PCP infection - unexplained fever x 2 weeks
- HIV related candidiasis
PCP prophylaxis
- single strength TMP-SMX (Bactrim fo
* * discontinue PCP prophylaziz when CD4 > 200 for 3 months
Mycobacterium avium complex (MAC)
prophylaxis indicated when CD4 count < 50-100
- treated with weekly azithromycin
- discontinue prophylaxis when CD4 count is > 100 for > 6 months
Toxoplasma gondii (HIV +)
prophylaxis indicated < 100 with positive IgG serologies
- prophylaxis with double strength Bactrim
M tuberculosis (HIV +)
prophylaxis indicated PPD > 5mm
- treated with isonizaid x 9 months (+ pyridoxine) or rifampin (4 months)
- include pyridoxine with INH-containing regiments
`
Candida prophylaxis (HIV +)
prophylaxis indicated at multiple recurrences
esophagitis prophylaxis: fluconazole
oral: nystatin swish and swallow
