Question

All but which one of the following are examples of secondary immunodeficiencies? a. HIV/AIDS b. malnutrition c. chronic granulomatous disease d. immunosuppression due to measles infection

Short answer

c. chronic granulomatous disease

Step-by-step solution

Understand Primary vs Secondary Immunodeficiencies

Primary immunodeficiencies are congenital and usually hereditary, present from birth. Secondary immunodeficiencies are acquired after birth due to external factors such as infections, malnutrition, or medical treatments.

Analyze Each Option

Evaluate each choice to determine if it is a primary or secondary immunodeficiency.

Option a: HIV/AIDS

HIV/AIDS is caused by the human immunodeficiency virus, leading to acquired immunodeficiency. It is a secondary immunodeficiency.

Option b: Malnutrition

Malnutrition weakens the immune system as a result of inadequate nutrition. It is classified as a secondary immunodeficiency.

Option c: Chronic granulomatous disease

Chronic granulomatous disease is a hereditary disorder that affects the ability of immune cells to kill certain bacteria and fungi. It is a primary immunodeficiency.

Option d: Immunosuppression due to measles infection

Measles infection can cause a temporary weakening of the immune system (immunosuppression). This makes it a secondary immunodeficiency.

Identify the Correct Answer

Only chronic granulomatous disease is a primary immunodeficiency. All other options are secondary immunodeficiencies.

Key concepts

HIV/AIDS

HIV/AIDS is a major example of a secondary immunodeficiency. Secondary immunodeficiencies are conditions that develop after birth due to external factors.
The human immunodeficiency virus (HIV) targets the immune system, specifically CD4+ T cells, and gradually destroys the body's ability to fight infections and certain cancers. This results in acquired immunodeficiency syndrome (AIDS).
Key points to remember about HIV/AIDS include:

• Transmission: It is primarily spread through unprotected sexual contact, sharing needles, or from mother to child during birth or breastfeeding.
• Symptoms: Early symptoms might include flu-like illness, while later stages can lead to severe infections and cancers.
• Treatment: No cure exists, but antiretroviral therapy (ART) can control the virus, helping patients lead longer, healthier lives.

Malnutrition

Malnutrition is another example of secondary immunodeficiency. It occurs when the body does not get enough nutrients, whether due to lack of food intake, poor diet, or absorption issues. This deficiency weakens the immune defenses.
Key aspects of malnutrition include:

• Types: Protein-energy malnutrition and micronutrient deficiencies (e.g., vitamin A, zinc, iron).
• Effects: Can cause stunted growth, weakened immune response, increased susceptibility to infections, and delayed wound healing.
• Prevention: Proper nutrition, supplementation, and addressing underlying causes like poverty or disease can help prevent malnutrition.

Immunosuppression from Infections

Certain infections can temporarily or persistently suppress the immune system, leading to secondary immunodeficiency. This is because some pathogens directly target or impair immune cells.
A common example is measles:

• Measles: Can cause a significant decrease in white blood cells, leading to immunosuppression that can last for weeks to months.
• Characteristics: Fever, rash, cough, and in severe cases, complications like pneumonia or encephalitis.
• Prevention: Vaccination is the most effective way to prevent measles and related immunosuppression.

Primary Immunodeficiencies

Primary immunodeficiencies are inherited conditions present from birth. They result from genetic defects affecting the immune system's development or function.
Key points include:

• Types: There are over 300 types of primary immunodeficiencies, including Severe Combined Immunodeficiency (SCID) and Chronic Granulomatous Disease (CGD).
• Diagnosis: Often identified in childhood through genetic testing and evaluation of frequent or unusual infections.
• Treatment: Can vary by condition but may include immunoglobulin replacement therapy, bone marrow transplants, or gene therapy.

Chronic Granulomatous Disease

Chronic Granulomatous Disease (CGD) is a type of primary immunodeficiency. CGD is a hereditary condition that affects the immune system's ability to effectively combat certain bacteria and fungi.
Important facts about CGD:

• Cause: Defects in the gene responsible for producing reactive oxygen species in phagocytes, which are crucial for killing pathogens.
• Symptoms: Frequent and severe bacterial and fungal infections, granuloma formation, and inflammation.
• Treatment: Includes antibiotics, antifungals, and sometimes stem cell transplants to correct the immune defect.