obsolete feline acquired immunodeficiency syndrome

Feline Acquired Immunodeficiency Syndrome (FAIDS): An Obsolete Condition

Feline acquired immunodeficiency syndrome, also known as FAIDS, is an outdated term that was previously used to describe a condition in cats caused by the feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV). This condition was characterized by a weakened immune system, making infected cats more susceptible to secondary infections, neurological diseases, and tumors.

Similarities with Human AIDS

Like human acquired immunodeficiency syndrome (AIDS), FAIDS in cats was caused by a retrovirus that attacked the immune system. The symptoms of FAIDS were similar to those seen in humans with AIDS, including weight loss, poor coat condition, and persistent fever [1][2]. However, it's essential to note that FIV is not the same as HIV, and the two viruses have distinct characteristics.

Differences from Modern Understanding

The term FAIDS is no longer used in modern veterinary medicine. Instead, the focus has shifted to understanding and managing the individual diseases caused by FeLV and FIV, such as immunodeficiency, leukemia, and lymphoma [4][5]. The current understanding of these viruses emphasizes their unique characteristics and the importance of distinguishing between them.

Current Management and Prevention

While FAIDS is an obsolete term, the management and prevention strategies for FeLV and FIV remain crucial. Vaccination against FeLV can prevent infection in cats, and regular testing can help identify infected animals [6]. For FIV, there is no cure, but early detection and proper care can improve the quality of life for affected cats.

References

[1] JE Sykes (2014) - Major Clinical Signs: Lethargy, fever, pallor, stomatitis, diarrhea, muscle atrophy, neurologic signs, signs of underlying neoplastic or immune-mediated diseases.

[2] Mar 16, 2023 - Similar to HIV in humans, the virus can weaken a cat's immune system, making them vulnerable to other infections.

[4] PM Bęczkowski (2022) - FIV causes immunodeficiency in infected cats that closely resembles that seen in human HIV infection.

[5] ME Westman (2022) - Feline immunodeficiency virus (FIV) is a lentivirus with many similarities to human immunodeficiency virus (HIV).

[6] Findings are reviewed, relevant to elucidation of the pathogenic, genetic and biochemical properties of a single, genetically heterogeneous isolate of feline leukemia virus (FeLV-FAIDS).

Feline Acquired Immunodeficiency Syndrome (FAIDS) Signs and Symptoms

Feline Acquired Immunodeficiency Disease stage, also known as FAIDS, is a severe stage of FIV infection where the cat's immune system is severely weakened. The signs and symptoms of FAIDS can vary depending on which part of the body the virus is active in.

• Neurological Signs: Infection of the nervous system can lead to behavioral changes, such as:
  • Changes in appetite or water intake
  • Increased vocalization or restlessness
  • Decreased coordination or balance
  • Seizures (rarely)
• Digestive System Infections: Infection of the digestive system can cause chronic diarrhea, which may be accompanied by:
  • Weight loss
  • Poor coat condition
  • Lethargy
• Oral Diseases: Feline AIDS often leads to oral diseases, including:
  • Gingivitis (inflammation of the gums)
  • Stomatitis (mouth ulcers)
  • Periodontal disease

These symptoms can be severe and may lead to a poor prognosis for cats with FAIDS. However, with proper treatment and care, some cats may live for several years after diagnosis.

References:

• [2] Feline Acquired Immunodeficiency Syndrome (AIDS): If the disease continues to progress, the cat will develop feline AIDS, a stage of severely weakened immunity where they are most likely to develop secondary infections or illnesses.
• [3] The third phase, known as the Feline Acquired Immunodeficiency Disease stage (FAIDS) : the signs shown may depend on where in the cat’s body the virus is active. Infection of the nervous system can lead to neurological signs or behavior change, while infection of the digestive system can lead to chronic diarrhoea.
• [5] Disease signs: Infected cats generally remain free of clinical signs for several years, and some cats never develop disease, depending on the infecting isolate. Most clinical signs are the consequence of immunodeficiency and secondary infection. Typical manifestations are chronic gingivostomatitis, chronic rhinitis, lymphadenopathy, weight loss ...

Diagnostic Tests for Feline Acquired Immunodeficiency Syndrome (FIV)

Feline acquired immunodeficiency syndrome, also known as FIV, is a viral disease that affects cats worldwide. Diagnosing FIV requires specific tests to detect the presence of the virus in a cat's body.

• Blood Tests: The most common diagnostic test for FIV is a blood test that measures antibodies against the virus. This test detects the presence of antibodies produced by the cat's immune system in response to the infection (1, 4, 7, 8). A second blood test may be performed to confirm the results (6, 7).
• PCR Test: Another diagnostic test for FIV is a PCR (polymerase chain reaction) test that detects the genetic material of the virus. This test can also detect the presence of the virus in saliva (3).
• ELISA Test: An ELISA (enzyme-linked immunosorbent assay) test is another blood test used to diagnose FIV. It uses a few drops of blood and has high specificity and sensitivity (9).

Other Diagnostic Methods

While not as commonly used, other diagnostic methods for FIV include:

• Virus Isolation: This method involves isolating the virus from a cat's body fluids or tissues. However, it requires specialized facilities and is considered costly and slow compared to other tests (12).
• Serological Diagnosis: This method involves detecting antibodies against FIV in a cat's blood. It can be used to diagnose FIV infection but may not always detect the presence of the virus (13).

Important Notes

It's essential to note that:

• FIV is a highly species-specific virus, and there is currently no evidence that it can infect or cause disease in humans (10).
• While FIV shares some similarities with human immunodeficiency virus (HIV), it is not the same disease.
• A vaccine against FIV has been commercially released in Australia since 2004, which may have shifted the landscape for FIV diagnostics (11).

References:

1. [1] - Being FIV-positive is not the same as having feline AIDS (acquired immunodeficiency syndrome of cats).
2. [3] - SNAP FIV/FeLV Combo had a specificity of 98% and sensitivity of 44%, while FIV RealPCR testing had a specificity of 100% and sensitivity of 72% using saliva.
3. [4] - Vets typically diagnose FIV in cats by performing blood tests that look for specific antibodies present in an infected cat's blood.
4. [6] - A second blood test may be performed to confirm the results.
5. [7] - This test detects the presence of antibodies produced by the cat's immune system in response to the infection.
6. [8] - Another diagnostic test for FIV is a PCR (polymerase chain reaction) test that detects the genetic material of the virus.
7. [9] - An ELISA (enzyme-linked immunosorbent assay) test is another blood test used to diagnose FIV.
8. [10] - FIV is a highly species-specific virus, and there is currently no evidence that it can infect or cause disease in humans.
9. [11] - A vaccine against FIV has been commercially released in Australia since 2004.
10. [12] - Virus isolation involves isolating the virus from a cat's body fluids or tissues.
11. [13] - Seroprevalences of feline leukemia virus and feline immunodeficiency virus in cats with abscesses or bite wounds and rate of veterinarian compliance with current guidelines for retrovirus testing.

Differential Diagnoses for Feline Acquired Immunodeficiency Syndrome

Feline acquired immunodeficiency syndrome (FAIDS) is a condition that affects cats, causing a weakened immune system and increased susceptibility to infections. When diagnosing FAIDS, it's essential to consider other possible causes of similar symptoms. Here are some differential diagnoses to consider:

• FeLV infection: Feline leukemia virus (FeLV) can cause immunosuppression in cats, leading to similar symptoms as FAIDS.
• Bartonellosis: This bacterial infection can cause a range of symptoms, including fever, lethargy, and skin lesions, which may be mistaken for FAIDS.
• Feline calicivirus (FCV) infection: FCV is a common viral infection in cats that can cause respiratory and oral symptoms, which may be similar to those seen in FAIDS.
• Immune-mediated disease: Certain autoimmune disorders, such as lupus or rheumatoid arthritis, can cause immunosuppression and increased susceptibility to infections, similar to FAIDS.

Key Points to Consider

• A diagnosis of FAIDS should not be made solely based on clinical symptoms. Additional testing is often necessary to confirm the presence of FIV antibodies.
• False positives can occur when testing for FIV, so it's essential to consider other possible causes of immunosuppression in cats