Case Studies
The patient, a 30-year-old homosexual man, complained of unexplained weight loss, chronic
diarrhea, and respiratory congestion during the past 6 months. Physical examination revealed
right-sided pneumonitis. The following studies were performed:
Studies Results
Complete blood cell count (CBC), p. 156
Hemoglobin (Hgb), p. 251 12 g/dL (normal: 14–18 g/dL)
Hematocrit (Hct), p. 248 36% (normal: 42%–52%)
Chest x-ray, p. 956 Right-sided consolidation affecting the posterior
lower lung
Bronchoscopy, p. 526 No tumor seen
Lung biopsy, p. 688 Pneumocystis jiroveci pneumonia (PCP)
Stool culture, p. 797 Cryptosporidium muris
Acquired immunodeficiency syndrome
(AIDS) serology, p. 265
p24 antigen Positive
Enzyme-linked immunosorbent assay
(ELISA)
Positive
Western blot Positive
Lymphocyte immunophenotyping, p. 274
Total CD4 280 (normal: 600–1500 cells/L)
CD4% 18% (normal: 60%–75%)
CD4/CD8 ratio 0.58 (normal: >1.0)
Human immune deficiency virus (HIV)
viral load, p. 265
75,000 copies/mL
Diagnostic Analysis
The detection of Pneumocystis jiroveci pneumonia (PCP) supports the diagnosis of AIDS. PCP is
an opportunistic infection occurring only in immunocompromised patients and is the most
common infection in persons with AIDS. The patient’s diarrhea was caused by Cryptosporidium
muris, an enteric pathogen, which occurs frequently with AIDS and can be identified on a stool
culture. The AIDS serology tests made the diagnoses. His viral load is significant, and his
prognosis is poor.
The patient was hospitalized for a short time for treatment of PCP. Several months after he was
discharged, he developed Kaposi sarcoma. He developed psychoneurologic problems eventually
and died 18 months after the AIDS diagnosis.
Case Studies
Copyright © 2018 by Elsevier Inc. All rights reserved.
2
Critical Thinking Questions
- What is the relationship between levels of CD4 lymphocytes and the likelihood of
clinical complications from AIDS?
- Why does the United States Public Health Service recommend monitoring CD4
counts every 3–6 months in patients infected with HIV?
- This is patient seems to be unaware of his diagnosis of HIV/AIDS. How would you
approach to your patient to inform about his diagnosis?
- Is this a reportable disease in Florida? If yes. What is your responsibility as a
provider?
Full Answer Section
The following are some of the most common opportunistic infections in people with AIDS:
- Pneumocystis jiroveci pneumonia (PCP)
- Cryptosporidiosis
- Mycobacterium tuberculosis (TB)
- Candidiasis
- Kaposi sarcoma
The United States Public Health Service recommends monitoring CD4 counts every 3-6 months in patients infected with HIV because it helps to identify patients who are at risk of developing clinical complications from AIDS. Early identification and treatment of opportunistic infections can improve the patient's prognosis.
The following table shows the relationship between CD4 lymphocyte levels and the likelihood of certain opportunistic infections:
| CD4 lymphocyte level (cells/μL) |
Opportunistic infection |
Risk of developing |
| >500 |
Low |
Low |
| 200-500 |
Medium |
Increased |
| <200 |
High |
Very high |
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As you can see, the risk of developing opportunistic infections increases as the CD4 lymphocyte level decreases. This is why it is important to monitor CD4 counts regularly in patients infected with HIV.
In the case study you provided, the patient's CD4 lymphocyte level was 280 cells/μL. This is considered to be a low CD4 lymphocyte level, and the patient was at high risk of developing opportunistic infections. The patient did develop PCP, which is a common opportunistic infection in people with AIDS.
The patient's viral load was also high at 75,000 copies/mL. This means that the virus was replicating rapidly in the patient's body. A high viral load is associated with a faster decline in CD4 lymphocyte levels and a higher risk of developing clinical complications from AIDS.
The patient died 18 months after the AIDS diagnosis. This is typical of the life expectancy of people with AIDS who are not treated with antiretroviral therapy (ART). ART is a type of medication that can suppress the HIV virus and prevent it from destroying CD4 lymphocytes.
ART has revolutionized the treatment of AIDS. ART has made it possible for people with AIDS to live long and healthy lives. However, it is important to note that ART is not a cure for AIDS. The virus remains in the body even when it is suppressed by ART.
If you are infected with HIV, it is important to see a doctor regularly for monitoring and treatment. ART can help to improve your prognosis and reduce your risk of developing clinical complications from AIDS.
Sample Answer
There is a direct correlation between the level of CD4 lymphocytes and the likelihood of clinical complications from AIDS. CD4 lymphocytes are a type of white blood cell that plays a vital role in the immune system. They help to fight off infection and disease.
As the HIV virus progresses, it destroys CD4 lymphocytes. This weakens the immune system and makes the body more susceptible to infections and diseases, including opportunistic infections. Opportunistic infections are infections that take advantage of a weakened immune system to cause disease.