OBJECTIVES

The main objective of this project was to assess the therapeutic effect of Zidovudine (AZT) on cats infected with either FIV or FeLV at late but not terminal stages of the respective diseases.

MATERIALS

The clinical trial was started with 10 FIV-infected cats (group 1), 3 FeLV-infected cats (group 2) and 15 healthy FIV/FeLV negative cats (control group). The control group was used just for technique's standardization, i.e., Flow Cytometry. Diagnosis was performed by ELISA, detecting p27 antigen for FeLV or antibodies for FIV, in whole blood samples. A nested PCR was standarized to confirm FIV status. Treatment with AZT was attempted at an oral dose of 5 mg/Kg, TID during 5 weeks with resting intervals of 4 weeks. The patient's follow up was done weekly, including clinical check up, hemogram, plasmatic globulin dosage and evaluation of CD4/CD8 rate by means of flow cytometry. During therapeutic phase AZT was the only drug used on study groups.

RESULTS

The FIV (+) study group presented the following clinical signs : lymphadenopathies 83%, gingivitis 67%, pneumonias 27%, pyodermia 29% uveitis 21%. The FeLV (+) study group showed spastic pupil syndrome, immunomediated glomerulonephritis and chronic gastroenteritis.

A significant increase (p<0.05, paired T Test with 5% significance rate) in the CD4/CD8 ratio was found between the 3rd and 4th weeks post-treatment onset in treated cats compared to time zero. Most of the patients (80%) underwent 2 years of treatment showing evident enhancement of physical condition: increase of bodyweight, recovery from gingivitis, pyodermias and pneumonias, decrease of lymphadenopathies and lack of opportunistic infections. The side effects, more often observed, In control and study groups, were diarrhea, anemia and adynamia. These effects were reversible and controlled upon treatment interruption.

CONCLUSION

Controlling FIV or FeLV infections could be achieve by means of anti-retroviral therapies. The use of AZT at 5 mg/Kg TID proved to be effective and safe. However, a tight follow up on patient's conditions should be done including hemograms and determination of CD4/CD8 rates.