Download opportunistic infections in hiv

9th Annual Mini Medical School
Idaho WWAMI Mini Medical School, Feb. 23rd
Casi M. Wyatt, DO
Sawtooth Infectious Diseases & Epidemiology
OPPORTUNISTIC
INFECTIONS IN HIV
Objectives
1. Define “Opportunistic Infection”
2. Gain a better understanding of the CD4 cell’s
role in the immune system
3. Recognize the spectrum of opportunistic
infections in HIV

Highlight a few examples via case presentations
4. Overview of the concepts behind treatment
and prevention of these infections
A definition
Opportunistic Infections
http://en.wikipedia.org/wiki/Trojan_Horse
Opportunistic Infections
 Infections that take advantage (seize an
opportunity) of a compromised immune system
 Can be the presenting illness in a person with
undiagnosed HIV
 Occur in HIV when people
 Don’t have access to HIV care
 Are unable to adhere to or tolerate treatment
 The HIV infection has become resistant to many
treatment options
Opportunistic Infections
 Less likely to have a rapid onset and sudden fatality
 “Smoldering” type of symptoms that progress
slowly over time
 Eventually can lead to death
 Usually more than one infection is present at a time
 Greatly affect quality of life




Diarrhea
Altered taste contributing to malnutrition
Difficulty breathing
Fatigue
The CD4 Cell
Opportunistic Infections
niaid.nih.gov
The CD4 cell
 Key immune cell infected by HIV
 CD4 cells do not kill invaders (pathogens)
 CD4 cells coordinates complex interactions with
other immune cells that are responsible for killing
pathogens
 Release chemicals (cytokines) to activate other immune
cells
 Recruit “killer” cells to sites of infection
 HIV infection
 Decreases the number of CD4 cells
 Leaves residual cells non-functional
The CD4 cell
 A decrease in CD4 cells adversely affects both
types of immunity:
 Causes B cell (antibody) dysfunction causing altered
Humoral immunity
 Predisposes to pneumococcus, meningococcus, Giardia, etc.
 Causes dysfunction of Cell-mediated immunity
 Predisposes to PCP, viruses, mycobacteria and fungi,
etc.
So…The CD4 Cell
 Activates and Recruits
 Other immune cells that are responsible for killing
invaders
 Without CD4 cells, invaders take advantage of
this “opportunity” and can remain undetected
for prolonged periods of time
Creating an environment that is analogous to
a slow decay…
http://www.youtube.com/watch?v=n5-0TK4TxkM
The relationship of the CD4 cell and incidence of
opportunistic infections
OI’s
200
CD4 cells
CDC Stages of HIV
Stage 1
CD4 > 500
HIV infection
Stage 2
CD4 = 200-499
HIV infection
Stage 3
CD4 < 200
AIDS*
If an “AIDS-defining illness (AIDS indicator
disease)” is present, stage as“AIDS” regardless
of CD4 count.
cdc.gov
The Spectrum
Opportunistic Infections
Most common OI’s
 Candida esophagitis
 Pneumocystis jirovecii (PCP) pneumonia
 Disseminated Mycobacterium avium Complex
(MAI/MAC)
 Cytomegalovirus (CMV)
Moore RD. AIDS. 1992 Jul;6(7):671-7
The spectrum
of OI’s:
 Fungi



Candidiasis
Cryptococcus
PCP pneumonia
 Viruses



Recurrent HSV
CMV
Influenza
 Bacteria


Mycobacterium: tuberculosis, MAI
Streptococcus pneumoniae
 Parasites



Toxoplasmosis
Cryptosporidiosis, Isospora
Scabies
mtflyfishingschool.com
Case 1
 27 year old male presents to the emergency
department complaining of “shortness of
breath”.
 He has no know medical illnesses but over the
last 4-5 months has had increasing fatigue,
swollen lymph nodes and frequent night sweats
 His temperature is 100.4 F, heart rate rapid,
respiratory rate increased. At rest his oxygen
saturation is 93% (low normal) but when he
walks it drops to 86% (very low)
Case 1
vardb.org
radRounds.com
Case 1: PCP Pneumonia
Pneumocystis jirovecii (formerly P. carinii)
 The most common OI in AIDS
 Very common presenting illness during AIDS epidemic in
1980’s
 Still a common AIDS-defining illness in newly diagnosed
HIV today
 A fungal infection
 CD4 cell critical in controlling the infection
 Treatment is a sulfa-based antibiotic (Bactrim) and
sometimes a steroid
 Prophylaxis with Bactrim in patients with CD4 <
200 has greatly reduces the incidence of this
infection
Oral/esophageal candidiasis
lib.uiowa.edu
 Yeast infection
 Not life threatening
 Does not spread
systemically
 Affects ability to eat and
thus overall contributes to
malnutrition in HIV infected
patients
lib.uiowa.edu
en.wikipedia.org
depts.washington.edu
Cytomegalovirus (CMV)
 Wide spectrum of
illness
 Retinitis
 Most common
 CD4 usually < 50
 Can result in blindness if
not treated urgently




eyesite.ca
Esophagitis
Enterocolitis/Proctitis
Pneumonia
Encephalitis
eyediseases.nl
Case 2
 A 35 year old female presents to an urgent care
complaining of cough, weight loss and night
sweats
 She has a history of IV heroine addiction and
has frequently lived in homeless shelters
 Her vital signs are normal. Her right lung has
diminished sounds at the apex. She also has
enlarged lymph nodes of her neck, axillae and
inguinal areas.
Case 2 cont.
jyi.org
homepage.smc.edu
Is it tuberculosis or
MAC (mycobacterium
avium complex)?
emedicine.medscape.com
Mycobacterial infections: TB & MAI
 Both are opportunistic infections in HIV infected
individuals
 Diagnosis is made on culturing the organism
 Newer genetic tests are available
 Only tuberculosis is a public health threat and can
be spread person-to-person
 Both have the risk of disseminating in HIV infected
people
 Lymph nodes, GI tract are common sites
 Therapy is long and requires multiple drugs
Scabies
 An ectoparasite that

medskin.co.uk



stanford.edu
burrows under the skin
Highly contagious with
skin-to-skin contact
Can survive 24-36 hours
at room temperature
Intense itching
Crusted scabies
 More severe
 Higher mite load in AIDS
 More contagious!
Kaposi's Sarcoma (Human Herpes Virus Type
8)
 Most recently discovered




herpes virus
Purple-to-brown
patch/plaque/nodule
Biopsy needed to confirm
diagnosis
Assoc’d with
lymphoma/lymphoprolife
rative cancers
Treatment not curative
 Involves topical and
systemic chemotherapy
webmd.com
Case 3
 A 45 year old male was brought to the
Emergency Department after having a seizure at
a restaurant
 He has also been having fevers, headaches and
confusion for the past 2 weeks
Case 3: Rapid HIV test is +
hakeem-sy.com
Brain lesions and HIV:
Possibilities are numerous
 Toxoplasmosis gondii
 Parasite
 Raw meat or contact with cat feces
 Primary central nervous system lymphoma
 Progressive multifocal leukoencephalopathy (PML)
 Reactivation of latent JC virus
 CMV
 Neurocysticercosis
 Parasite from undercooked pork; most common in immigrant
populations
 Diagnosis usually requires more imaging, spinal tap,
serologic tests and sometimes brain biopsy
Treatment and Prevention
Opportunistic Infections
Treatment
 In general, is a 2-tiered approach
 Appropriate antimicrobial agent(s)
 Initiating HAART
 Patient may be at risk for IRIS
 Immune reconstitution inflammatory syndrome
eyesite.ca
Prevention
 Prophylaxis: based on history of prior infection and
current CD4 count
 TMP/SMX (Bactrim): PCP, toxoplasmosis
 Azithromycin: MAC
 Vaccines:
 Inactivated vaccines are safe in HIV
 Pneumococcal vaccine
 Influenza vaccine annually
 Hepatitis A, B vaccines
 Live vaccines: can be considered in certain cases and in
patients with higher CD4 counts
 Start HAART earlier????
In Summary
Opportunistic Infections
In summary
 The CD4 cell activates and recruits other cells
of the immune system. In HIV when this cell is
infected, microbes have an “opportunity” to
invade and go undetected for prolonged periods
of time. The lower the CD4 cell count, the
higher the risk and broader the spectrum of
opportunistic infections in HIV
In summary
 The spectrum of opportunistic infections
(illnesses) is broad and includes
 Bacteria
 Viruses
 Parasites
 Fungi
 And other illnesses: dementia, malignancy
In summary
 Treatment
 Involves
1. Treating the infection
2. Treating the HIV

This is the real key to therapy
 Prevention
1. Prophylaxis against infection
2. Vaccines to help prevent infection
3. Treating the HIV
Thank You.