80 Hematologic Manifestations of Human Immunodeficiency Virus and the Acquired Immunodeficiency Syndrome Flashcards
HIV-1, the virus that causes AIDS, is a ___________ that originated as a simian immunodeficiency virus (SIV) in chimpanzees and entered the human population in the early 20th century in equatorial Africa
Lentivirus
HIV-1 actually comprises four distinct viruses
Types M, N, O, and P
The viral type responsible for the HIV-1 pandemic, was detected in a tissue sample from 1959 and probably entered the human population in or around Kinshasa, Democratic Republic of Congo (then Leopoldville, Belgium Congo) between 1910 and 1930
Group M
The result of cross-species transmission of SIV from sooty mangabeys to humans
HIV-2
HIV1 or HIV2
Progress with disease more slowly and have lower plasma viral loads (often nondetectable)
HIV2
The globally predominant viral strain and is further divided into nine subtypes and many more recombinant viruses (circulating recombinant forms [CRFs]) with some geographic localization
Group M
Geographic localization of Group M
Subtypes A and D:
Subtype C:
Subtype B:
CRF01:
Geographic localization of Group M
Subtypes A and D: East Africa
Subtype C: most prevalent subtype globally, in South Africa, India, and Asia
Subtype B: Caribbean, the Americas, and Western Europe
CRF01:Southeast Asia
Predominant mode of transmission in the following areas:
United States, Northern Europe, Australia, and parts of Central and South America:
Sub-Saharan Africa:
Southern and Eastern Europe and Southeast Asia:
Predominant mode of transmission in the following areas:
United States, Northern Europe, Australia, and parts of Central and South America: sexual contact between men
Sub-Saharan Africa: heterosexual spread
Southern and Eastern Europe and Southeast Asia:injection drug use followed by sexual transmission
Eighty percent of HIV infections occur via ____________________when cell-free and cell-associated virions transverse the epithelium to gain access to macrophages, Langerhans cells, dendritic cells, and CD4-expressing T lymphocytes.
Mucosal transmission during sex
To infect most cells, HIV must bind to CD4 and one of two major coreceptors:
CCR5 or CXCR4
** In most cases, CCR5-utilizing viral strains are those that are transmitted and predominate early in disease
Replication of HIV occurs in
tissue macrophages and dendritic cells
Typically, the asymptomatic phase of chronic infection will last for ________, although there is great interindividual variation dictated by the effectiveness of the immune response in controlling HIV replication
8 to 10 years
Those who maintain CD4+ T-cell counts >500 for 5 years without therapy
Long-term nonprogressors
Those with low or nondetectable plasma HIV RNA without treatment
Elite controllers
Tumors classified as AIDS-defining malignancies
Kaposi sarcoma
Cervical cancer
Certain subtypes of non-Hodgkin lymphoma (NHL) (initially Burkitt lymphoma)
Immunoblastic lymphoma
Primary CNS lymphoma
HIV STAGING: Infection within the previous 6 months
Stage 0
HIV STAGING: CD4 count ≥500 cells/μL (or ≥26%)
Stage 1
HIV STAGING: CD4 count 200–499 cells/μL
(or 14%–25%)
Stage 2
HIV STAGING: AIDS-defining condition or CD4 count <200 cells/μL (or <14%)
Stage 3
Opportunistic Infections by CD4 Count
> 500 cells/μL
Any condition that can occur in HIVuninfected
persons, eg, bacterial pneumonia, tuberculosis, varicella zoster, herpes simplex virus
Opportunistic Infections by CD4 Count
350–499 cells/μL
Thrush, seborrheic dermatitis, oral hairy
leukoplakia, molluscum contagiosum
Opportunistic Infections by CD4 Count
200–349 cells/μL
Kaposi sarcoma, lymphoma
Opportunistic Infections by CD4 Count
100–199 cells/μL
Pneumocystis pneumonia, Candida esophagitis, cryptococcal meningitis
Opportunistic Infections by CD4 Count
<100 cells/μL
Toxoplasma encephalitis, disseminated, Mycobacterium avium complex, progressive
multifocal leukoencephalopathy, cytomegalovirus retinitis, primary CNS lymphoma, microsporidia
TRUE OR FALSE
All HIV-infected persons be offered ART regardless of CD4 count
TRUE
All HIV-infected persons be offered ART regardless of CD4 count
Primary Prophylaxis: Pneumocystis pneumonia
CD4 <200 cells/μL or <14% or oral candidiasis or an AIDS-defining illness
Trimethoprimsulfamethoxazole or dapsone or
aerosolized pentamidine
Primary Prophylaxis: Tuberculosis
Purified protein derivative >5 mm or positive
interferon-γ release assay
Isoniazid and pyridoxine
Primary Prophylaxis: Toxoplasmosis
Immunoglobulin G+ and CD4 <100 cells/μL
Trimethoprimsulfamethoxazole or dapsone plus pyrimethamine plus leucovorin
Primary Prophylaxis: Mycobacterium avium complex
CD4 <50 cells/μL
Azithromycin or Clarithromycin
An acute inflammatory reaction as a result of reconstitution of the immune system in the presence of organisms or foreign antigens
Immune reconstitution inflammatory syndrome (IRIS)
Risk factors for the development of IRIS
Low baseline CD4 count
More severe disease
A short interval between treatment of the opportunistic infection and initiation of ART
Treatment of IRIS
Treatment of the underlying infection or condition
Continued ART
Antiinflammatory medication, such as glucocorticoids