ID 14 Flashcards
What happens during the latent phase of HIV infection?
Virus replicates in lymph nodes.
Time course of untreated HIV infection
1) First couple months = Acute phase – flu-like symptoms. CD4 count drops. Viral load rises. Wide dissemination of virus. Seeding of lymphoid organs.
2) 2 months - 8 years = clinical latency. Feeling fine.
3) Falling t-cell count with constitutional symptoms
4) Final crises – opportunistic diseases (9-10 years).
moderate immunocompromised with AIDS
less than 400 CD4+ cells/mm
JC virus on imaging
Nonenhancing areas of demyelination on MRI
aspergillus HIV presentation
hemoptysis + pleuritic pain
candida presentation in aids patient with T cell count below 100
esophagitis
Histoplasma presentation in AIDS patient with T cell count below 100
fever, weight loss, fatigue, cough dyspnea, nausea vomiting diarrhea
M avium presentation in AIDs patient with T cell count below 100
fever, night sweats, weight loss or focal lymphadenitis
t gondii presentation in AIDs patients
brain abscesses
aspergillus findings in AIDs patient
cavitation or infiltrates on chest imaging
CNS lymphoma in AIDS patient findings
ring enhancing
differentiating CNS lymphoma from toxoplasma
CNS lymphoma usually solitary vs. toxoplasma
Histoplasma path finding
oval yeast cells within macrophages
variant CJD
CJD transmitted through food contaminated by BSE-infected animal products
How do you kill prions?
can’t autoclave.
location of s mutans
dental plaque
flora of neonates delivered by C-section
No flora but are rapidly colonized after birth.
Food poisoning that starts early and ends early?
1) s aureus
2) b cereus
c perfringens source
reheated meat
salmonella sources
poultry
*meat
eggs
s aureus sources
*meats
*mayonnaise
custard
campylobacter shape
comma or S-shaped
salmonella lactose?
negative
c diff GI presentation?
watery; occasionally bloody
protozoa causing watery diarrhea?
giardia
cryptosporidium
C perfringens diarrhea type
watery
viruses diarrhea type
watery
salmonella diarrhea type
bloody
EIEC diarrhea type
bloody
most common causes of pneumonia in neonates (less than 4 weeks old)
GBS
e coli
most common causes of pneumonia in children (4 week - 18 years)
Viruses (RSV)
Mycoplasma
S pneumonia
most common causes of pneumonia in adults (18-40)
Mycoplasma
C pneumonia
S pneumonia
Viruses (influenza)
most common causes of pneumonia in adults (40-65)
S pneumonia H flu Anaerobes Viruses Mycoplasma
most common causes of pneumonia in elderly
S pneumonia Influenza virus Anaerobes H flu Gram negative rods
common causes of pneumonia in alcoholics
Klebsiella
*Anaerobes (eg, peptostreptococcus, fusobacterium, prevotella, bacteroides)
common causes of pneumonia in IV drug users
1) s pneumoniae
2) s aureus
most common causes of atypical pneumonia
mycoplasma, *legionella, chlamydia
common causes of pneumonia in CF
pseudomonas
- s aureus
- s pneumonia
- burkholderia cepacia
common causes of pneumonia in immunocompromised
*s aureus enteric gram negative rods fungi viruses P jirovecii with HIV
Causes of meningitis in newborns (0-6 months)
GBS
E coli
Listeria
Causes of meningitis in children (6 mo-6 years)
S pneumonia
N meningitides
H flu type B
enteroviruses
Causes of meningitis in 6-60 yr
S pneumo
N meningitis
enteroviruses
HSV
Causes of meningitis in 60+
S pneumo
gram negative rods
listeria
meningitis managment
ceftriaxone and vanco empirically (add ampicillin if Listeria is suspected)
Viral causes of meningitis
Enteroviruses (coxsackie) HSV-*2 HIV WNV VZV
When is H influenza usually seen?
unimmunized children.
Differentiating bacterial from fungal/TB meningitis
cell type
opening pressure in viral meningitis
normal or slightly elevated
CD4 count with HIV Dementia
200
CD4 count with Bacillary angiomatosis
500
CD4 count with JC virus/PML
200
CD4 count with aspergillus
100
CD4 count with t gondii
100
CD4 count with Kaposi sarcoma
500
CD4 count with Pneumocystis jirovecii
200
CD4 count with cryptosporidium
500
CD4 count with Candida
500
CD4 count with M avium
100
CD4 count with histoplasma
100
CD4 count with HPV (squamous cell carcinoma)
500
CD4 count with cryptococcus
100
CD4 count with CMV
100
CD4 count with oral hairy leukoplakia (EBV)
500
CD4 count with B-cell lymphoma
100
Most common cause of pneumonia in infants - 3 yr?
C trachomatis
Most common cause of pneumonia in school aged children?
C pneumonia
