The first case of feline cytauxzoonosis in Germany: clinical description and molecular confirmation

Abstract

Background Cytauxzoonosis is gaining clinical importance in recent years, being described as an emerging tick-borne disease of domestic and wild felids caused by protozoans of the genus Cytauxzoon . While in the Americas the condition is described as a fatal disease, in Europe, reports on the clinical expression of the infection are scarce. This study describes the first case of Cytauxzoon sp. infection in a domestic cat in Germany. Methods Clinical and laboratory findings, and molecular and DNA sequencing results were collected from a domestic cat suspected for cytauxzoonosis after the microscopic examination of a blood smear. Results A 6-year-old male domestic cat living in Saarlouis (Germany) was presented with a history of recent anorexia and weight loss. The cat had an outdoor lifestyle and had not travelled abroad. Serum clinical chemistry analysis revealed azotaemia with markedly increased symmetric dimethylarginine, hypercreatinemia, hyperphosphatemia and hypoalbuminemia. Moreover, a mild non-regenerative anaemia was present. Approximately one year prior these findings, the patient was diagnosed with a FIV infection. These results point toward a decreased glomerular filtration rate, presumably as a result of a kidney dysfunction. Therefore, a glomerulonephropathy was suspected. Round to oval signet-ring shaped intraerythrocytic organisms, morphologically suggestive for a piroplasm, were revealed during blood smear evaluation with a degree of parasitaemia of 32.95%. PCR analyses and sequencing of the partial 18S gene confirmed the presence of a Cytauxzoon sp. infection, with 99-100% nucleotide sequence identity with previously published Cytauxzoon sp. isolates. Conclusion This study provides the first case of molecularly confirmed Cytauxzoon sp. infection in a domestic cat in Germany and describes the clinical picture of the disease in association with FIV infection. These findings suggest that cytauxzoonosis should be considered as a differential diagnosis in cases of anaemia in domestic outdoor cats, particularly in areas where wild felid populations are present.

Arthropod-Borne Pathogens in Stray Cats from Northern Italy: A Serological and Molecular Survey

“…The BLAST analysis retrieved 100–99.75% identity with sequences deposited as Cytauxzoon sp. isolated from domestic cats in Germany (MN629916 [ 30 ]), in Switzerland (MF503141-8 [ 29 ]; KU306940-4, KU306945-8, Willi et al, Tochtermann et al unpublished), in France (KX881967 [ 28 ]; EU622908 [ 52 ]), and in Portugal (KU710344, [ 26 ]), as well as with isolates from the European lynx and the wild cat in Romania (KT361070-2, KT361074, KT361076, KT361079-81 [ 53 ]) and from the Iberian lynx in Spain (EF094468-70 [ 54 ]). Accordingly, in the NJ dendrogram the sequences obtained in this study clustered with other Cytauxzoon sp.…”

“…In Europe, cytauxzoonosis by C. felis has not been described; however, in the past decade, infections with a genetically distinct species described as Cytauxzoon sp. have been increasingly reported [ 28 ] in several European countries, both in domestic cat [ 26 , 27 , 28 , 29 , 30 , 56 , 57 ] and in wild felids, including the Iberian lynx ( L. pardinus ), the European lynx ( Lynx lynx ), and the European wild cat ( Felis silvestris silvestris ) [ 18 , 52 , 53 , 54 , 84 , 85 ]). The sequences described from Europe as Cytauxzoon sp.…”

“…A neighbor-joining (NJ) phylogram was constructed using Bioedit and MEGA-X software including the DNA sequences obtained in the present study and other sequences of Cytauxzoon spp. previously deposited in GenBank [ 18 , 26 , 28 , 30 , 52 , 53 , 54 , 55 , 56 , 57 ]. Sequencing and phylogenetic analysis was conducted only on Cytauxzoon spp.…”

“…However, a different pathogenicity, depending on the strains, was recently reported [ 22 ], and even domestic cats developing subclinical and persistent blood parasitaemia have been described [ 23 , 24 , 25 ], suggesting they may play a role as reservoir of infection [ 25 ]. Fewer epidemiological and clinical data on infections by species other than C. felis are available, especially for Europe [ 18 , 26 ], although several studies have been published lately [ 27 , 28 , 29 , 30 ]. Finally, Hepatozoon felis , H. canis , and H. silvestris are the etiological agents of feline hepatozoonosis [ 2 , 31 , 32 ].…”

A Novel Vaccine Strategy to Prevent Cytauxzoonosis in Domestic Cats

“…While C. felis is the only known species of the genus in the United States (US), other Cytauxzoon spp. have been identified in several countries from five different continents [ 4 , 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ]. Infection of domestic cats with C. felis causes cytauxzoonosis, a fatal tick-borne disease [ 13 ], and cases of cytauxzoonosis have been documented all over the southcentral, southeastern, and mid-Atlantic US [ 2 , 13 , 14 ].…”