HIV and T-Lymphocytes Overview

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Questions and Answers

What is the primary reason that individuals with a high viral load are more likely to transmit HIV?

They are more likely to engage in risky sexual behaviors.

A higher concentration of the virus makes them more infectious. (correct)

Their immune system is too weak to fight off the virus.

They show no symptoms during the acute phase.

At what CD4+ T-cell count does the immune problems typically start in HIV infection?

200 cells/mcL (correct)

500 cells/mcL

100 cells/mcL

300 cells/mcL

Which strategy is NOT considered a risk-reducing measure in HIV prevention?

Using pre-exposure prophylaxis (PrEP)

Consistent use of condoms

Regular HIV testing and counseling

Engaging in multiple concurrent sexual relationships (correct)

Which of the following activities is most safe for individuals living with HIV to engage in?

Participating in group sports without sharing personal items Signup and view all the answers

Which counseling practice is crucial in managing and preventing perinatal transmission of HIV?

Promoting antiretroviral therapy during pregnancy Signup and view all the answers

Which statement accurately describes the characteristics of HIV?

HIV requires contact with specific body fluids for transmission. Signup and view all the answers

Which group has the highest risk of HIV transmission in North America?

Men who have sex with men (MSM) Signup and view all the answers

What is a crucial strategy to prevent perinatal transmission of HIV during childbirth?

Administering antiretroviral therapy to the mother. Signup and view all the answers

What is one effective risk-reducing strategy for individuals engaging in sexual activities?

Using barrier methods consistently. Signup and view all the answers

HIV testing and counseling practices should prioritize what aspect for effective prevention?

Providing comprehensive information about safe sexual practices. Signup and view all the answers

Which symptom is most commonly associated with the intermediate chronic infection phase of HIV?

Oropharyngeal candidiasis Signup and view all the answers

What characterizes the early chronic infection stage of HIV?

Development of HIV-specific antibodies occurs Signup and view all the answers

During the late chronic infection phase, which of the following is a significant consequence of a compromised immune system?

Greater risk for opportunistic diseases Signup and view all the answers

What is the median timeline for untreated HIV to progress to AIDS?

10 years Signup and view all the answers

Which clinical manifestation is NOT typically associated with advanced HIV infection?

Weight gain Signup and view all the answers

At what CD4+ T cell count does the intermediate chronic HIV infection phase begin?

Between 200 and 499 cells/mcL Signup and view all the answers

Which of the following is a likely symptom during the late chronic infection phase of HIV?

Chronic fatigue Signup and view all the answers

What are the criteria necessary for diagnosing AIDS?

Presence of CD4+ T cells <= 200 cells/mcL and other opportunistic infections Signup and view all the answers

Study Notes

T-Lymphocytes and HIV

CD4 protein plays a crucial role in HIV progression to AIDS.
CD4+ receptor sites are the primary targets for HIV infection.
Infection leads to a significant alteration in immune system function.

Pathophysiology of HIV

HIV is a single-stranded RNA retrovirus that infects T-helper cells.
Reverse transcriptase converts HIV RNA into HIV DNA.
Integrase allows HIV DNA to enter the nucleus, becoming a part of the cell's genetic material.
This process produces copies of the virus, known as the "viral load."
High viral load correlates with the destruction of more CD4+ cells and surrounding immune cells.

Immune System Impact

Immune complications arise when CD4+ T-cell counts fall below a critical threshold, typically around 200 cells/mcL.
Normal CD4+ count ranges from 500-1600 cells/mcL.
Opportunistic diseases become prevalent and are the leading causes of morbidity and mortality in HIV patients.

Clinical Manifestations

Stage 1 – Acute Infection

Initial HIV infection triggers rapid replication within white blood cells (WBCs).
A high viral load leads to increased CD4 cell destruction, enhancing transmission potential.
Symptoms include fever, swollen lymph nodes, sore throat, headache, and rash within 1–3 weeks post-infection.

Stage 2 – Early Chronic Infection

Entered latency period where viral load stabilizes but ongoing CD4 destruction continues.
Antibodies against HIV develop; patients often remain asymptomatic but infectious.
This stage can last for many years, with a typical time frame of 10 years before progressing to AIDS.

Stage 3 – Intermediate Chronic Infection

CD4+ T-cell count drops below 500 cells/mcL while rising viral load indicates disease progression.
Symptoms may intensify, presenting as persistent fever, night sweats, chronic diarrhea, and fatigue.
Common infections during this phase include oropharyngeal candidiasis (thrush).

Common Infections in Intermediate Chronic Phase

Oropharyngeal candidiasis
Shingles
Oral hairy leukoplakia
Persistent vaginal Candida infections
Herpes and bacterial infections
Kaposi’s sarcoma (KS)

Stage 4 – Late Chronic Infection or AIDS

Severe immune system compromise characterizes this stage.
Progressive decrease in T-cell count with a rising viral load indicates a transition to AIDS.
Heightened risk for opportunistic infections, significant weight loss, and potential malignancies or dementia.

Diagnosis of AIDS

AIDS diagnosis requires meeting specific criteria related to immune system function and opportunistic infections.
Targets for HIV treatment and management aim to eliminate the AIDS epidemic by 2030, as suggested by UNAIDS.

Transmission

HIV is fragile; transmission occurs through contact with infected body fluids such as blood and sexual secretions.
Most common transmission method is sexual contact, especially among MSM (men who have sex with men).
HIV can also spread via needle sharing, blood transfusions, perinatal transmission, and breastfeeding.
Infected individuals can transmit HIV within days of infection.

Sexual Transmission

Sexual contact involving HIV-infected fluids poses the highest risk, especially for receptive partners.
Activities that cause mucosal trauma, like certain sexual practices or the presence of genital lesions, enhance transmission risk.

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Description

This quiz covers the critical role of CD4+ T-lymphocytes in HIV infection and disease progression. It explores the pathophysiology of HIV, the impact on the immune system, and the clinical manifestations of HIV/AIDS. Test your knowledge on how HIV affects T-cells and the overall immune response.