Archive Case #224: Feline Toxoplasmosis

Clinical Clues

1. A young cat develops fever, reduced appetite and increasingly rapid breathing over several days.
2. Thoracic imaging shows a diffuse interstitial pulmonary pattern rather than a single lobar consolidation.
3. Ophthalmic examination finds posterior uveitis, adding a second affected organ system.
4. Bronchoalveolar lavage is pursued because respiratory disease is progressing despite an unclear initial cause.
5. Cytology from the affected lung identifies intracellular crescent-shaped protozoal tachyzoites amid inflammation.
6. A Toxoplasma gondii-specific PCR assay on the same affected-site sample identifies the organism causing this pulmonary and ocular syndrome.

Diagnosis

Feline Toxoplasmosis

Pulmonary and ocular disease with tachyzoites in an affected-site sample and specific PCR supports clinical toxoplasmosis. Feline infectious peritonitis and other protozoal infections can overlap with the early signs, but the organism-specific result on diseased tissue separates this answer. Hunting history or isolated seropositivity would not prove active disease. Remember: In a sick cat, compatible lesions plus organism detection in affected tissue are stronger evidence of toxoplasmosis than exposure history or a lone antibody titre.

Educational Use

Vetdle archive cases are educational veterinary games for diagnostic reasoning practice. They do not provide veterinary advice, diagnosis, treatment, or professional medical guidance.