Heme-Onc: Systemic Infections I & II Flashcards
what are the infections of the lymphocytes
- HIV/AIDS - T-cells
- CMV - T-cells + macrophages
- Infectious mononucleosis - B-cells
HIV pathogenesis
HIV destroys T-cells and macrophages
- T-cell destruction
- HIV uses its gp120 receptor to bind
- CD4
-
either CXC-4 / CCR-5
- T-tropic: binds CXCR-4
- M-tropic: binds CCR-5
- once in, replicates itself using host machinery: RT to turn its RNA genome into DNA,
incorporates into host DNA
- HIV uses its gp120 receptor to bind
T-tropic HIV binds what receptors? with what protein?
- using gp120 protein, binds Th cells at
- CD4
- CXCR-4
M-tropic HIV binds what receptors with what protein?
- using gp120 protein, binds Th cells at
- CD4
- CCR-5
what are the various HIV subtypes and which are m/c in the US?
- HIV-1
- m/c in US: M-type, B subgroup
- HIV-2 - seen in west africa
what are the stages of HIV?
- stage 1: acute HIV infection
- stage 2: clinical latency stage
- stage 3: AIDS
stage 1 of HIV
- what is seen in the blood during the phase?
- clinical presentation?
acute phase
- antibodies titers are high at the END of this stage
- presentation
- asymptomatic, or
- mononucleosis sx, or
- combination of
- myalgia
- arthralgia
- hepatosplenomegaly
- meningitis
- encephalitis rash
stage 2 of HIV
- what is seen in the blood during the phase?
- clinical presentation?
clinical latency phase
- blood
- antibody titers high throughout
- CD4 cells drops from 500 → 200
- presentation
- lymph nodes start breaking down
- certain manifestations:
- AIDS-related complex (ARC)
- PGL - persistent generalized lymphadenopathy
stage 3 of HIV
- what is seen in the blood during the phase?
- clinical presentation?
= AIDS
- in the blood
- CD4+ cells decline below 200 (or, presence of aids defining illness)
- viral p24 increases
- HIV antibody titers DECLINES
- presentation
- ARC
- PGL
- CNS disease
- wasting disease
what are the means of transmission of HIV?
what are the m/c way HIV is transmitted
- in the world
- in the US
- in men in the US
- in women in the US
- transmitted
- sexually - anal, vaginal
- maternal-child: placenta, peripartum, breast milk
- blood - transfusion, needle
most common:
- world - heterosexual
- US - homosexual
- US men = homosexual
- US women =- heterosexual
discuss the classification of AIDS.
how is each class defined?
each class is based on the presence of other symptomatic conditions along-side HIV:
A: asymptomatic, acute HIV or PGL
B: conditions that are attributed to HIV infection, but is not quite AIDS defining
- thrush (but not esophagitis)
- cervical carcinoma in situ (but not invasive)
- bacillary angiomatosis
- hair oral leukoplakia
C: AIDS defining illnesses
- esophageal candida
- cervical carcinoma, invasive
- kaposi sarcoma
- pneumocystitis jiroveci pneumonia
- CMV retinitis
what clinical presentation of HIV constitutes AID?
- CD4
- either
- esophageal candida
- cervical carcinoma, invasive
- Kaposi’s sarcoma
- pneumocystis jiroveci pneumonia
- CMV retinitis
infectious mononucleosis (IM)
- etiologic agent?
- pathogenesis?
- heterophil positive IM
- EBV infects & multiple in the epithelial cells in the oropharynx → gets disseminated elsewhere
-
infects B-cells by binding to their CD21 receptor, inducing
- proliferation
- production of IgM Ab that the B-cells were already making + anti-EBV IgM
- → immune complex formation
infectious mononucleosis (IM) - presentation
- asymptomatic (usually)
- if symptomatic (worse in adults)
-
glandular fever triad:
- FEVER
-
PHARYNGITIS
- pharyngeal erythema + edema
- petechia on the hard/soft palates
- CERVICAL LYMPHDENOPATHY
- also
- palpebral edema
- splenomegaly / hepatosplenomegaly
-
glandular fever triad:
pharyngitis: part of glandular triad of IM (Epstein Barr Virus)
- pharyngeal erythema
- pharyngeal edema
- petechia on the hard/soft palates
cervical lymphadenopathy: part of glandular fever triad in IM (Epstein Barr Virus)
palpebral edema (bilateral upper eyelid swelling) - IM (Epstein Barr Virus)
what infectious can cause the glandular fever triad?
what is the glandular fever triad?
- EBV
- HIV
- CMV
- toxoplasmosis
fever + pharyngitis + cervical lymphadenopathy
complications of IM
- brain, spinal, nerves
- hematological
- other
- myocarditis
- pneumonia
- pancreatitis
- oral hairy leukoplakia
B and T cells
= Downy Cells
- formed by EBV infecting both B and T-cell lymphocytes (CD8, specifically)
- seen in peripheral blood smears
dx of EBV
- Downy cells on blood smear
-
heterophile Ab test (monospot)
- pts IgM Ab react against RBCs
- EBV serologies
- heterophile IgM
- +/- acute infection
- anti-VCA IgM & IgG
- IgM - acute
- IgG - acute & chronic
- anti-EBNA Ab - past infection
- heterophile IgM
IBV serology - which Abs are seen in
- acute EBV mononucleosis
- past EBV infection
- acute infection
- +/- heterophile Ab
- anti-VCA IgM
- anti-VCA IgG
- past EBV infection
- anti-VCA IgG
- anti-EBNA IgG
possible AE of IM tx?
pt may develop rash if given ampicillin / amoxicillin
CMV infections - pathogenesis
- etiological agent (HHV-5) infections T-cells and macrophages
- spreads cell to cell, then → establishes latency
- tends to really only infect immunocompromised hosts
- spreads cell to cell, then → establishes latency
key manifestations of congenital CMV
usually - no symptoms
- microcephaly
- intracerebral calcifications
- CMV choriorhinitis (AIDS defining illness)
- thrombocytopenia, hepatosplenomegaly
CMV choriorhinitis
congenital CMV infection
intracerebral calcifications
congenital CMV infection
microcephaly
congenital CMV infection
children and adults - CMV presentation
usually asymptomatic unless host is immunocompromised
- in non-immunocompromised patients
- usually asymptomatic
- if symptomatic:
- mono-nucleolus like sx
- pneumonia
- hepatitis
- organ transplant rejection
- in immunocompromised patients:
- esophagitis
- colitis
- choriorinitis (CMV rhinitis)
what are the major manifestations of a CMV infection in an immunocompromised patient?
which patients are particularly susceptible to this presentation/
- esophagitis
- colitis
- chorioretinitis (CMV retinitis)
*m/c seen in AIDS patients
means of transmission of CMV
- congenital - note that CMV is the most common cause viral congenital defects
- perinatal
- adults - sexual, transfusions / transplants
diagnosis of CMV
- heterophile negative mononucleosis
- presence of Owl’s eyes
- atypical lymphocytosis
- abnormal LFTs
owl’s eyes
CMV
owl’s eyes
CMV
owl’s eyes
CMV
