The first clinical case of Hepatozoon felis infection in a cat from Panama.

Hepatozoon felis is the most prevalent Hepatozoon species infecting domestic cats worldwide; however, clinical disease is considered uncommon. This study describes the first clinically confirmed case of H. felis infection in a domestic cat from Panama. A 3-year-old male cat presented with painful periostitis of long bones, poor body condition and leukocytosis with marked neutrophilia. Hepatozoon gamonts were detected in neutrophils, and infection was confirmed by PCR and sequencing of the 18S rRNA gene. Phylogenetic analysis revealed a highly divergent H. felis lineage clustering separately from predominant European haplotypes. The cat was successfully treated with imidocarb, doxycycline and toltrazuril, achieving complete clinical recovery and PCR negativity. This report extends the known geographic range of H. felis to Central America and highlights its potential pathogenicity in immunocompetent cats.