Analysis of risk factors associated with recurrence of canine babesiosis caused by Babesia gibsoni

ACVIM consensus statement on the diagnosis of immune thrombocytopenia in dogs and cats

Immune thrombocytopenia (ITP) is the most common acquired primary hemostatic disorder in dogs. Immune thrombocytopenia less commonly affects cats but is an important cause of mortality and treatment-associated morbidity in both species. Immune thrombocytopenia remains a diagnosis of exclusion for which diagnostic guidelines are lacking. Primary, or non-associative, ITP refers to autoimmune platelet destruction. Secondary, or associative, ITP arises in response to an underlying disease trigger. However, evidence for which comorbidities serve as ITP triggers has not been systematically evaluated. To identify key diagnostic steps for ITP and important comorbidities associated with secondary ITP, we developed 12 Population Evaluation/Exposure Comparison Outcome (PECO) format questions. These questions were addressed by evidence evaluators utilizing a literature pool of 287 articles identified by the panelists using a structured search strategy. Evidence evaluators, using panel-designed templates and data extraction tools, summarized evidence and created guideline recommendations that then were integrated by diagnosis and comorbidity domain chairs. The revised PECO responses underwent a Delphi survey process to reach consensus on final guidelines. A combination of panel expertise and PECO responses were employed to develop algorithms for diagnosis of ITP in dogs and cats, which also underwent 4 iterations of Delphi review. Comorbidity evidence evaluators employed an integrated measure of evidence (IME) tool to determine evidence quality for each comorbidity; IME values combined with evidence summaries for each comorbidity were integrated to develop ITP screening recommendations, which also were subjected to Delphi review. Commentary was solicited from multiple relevant professional organizations before finalizing the consensus. The final consensus statement provides clinical guidelines for the diagnosis of, and underlying disease screening for, ITP in dogs and cats. The systematic consensus process identified numerous knowledge gaps that should guide future studies. This statement is a companion manuscript to the ACVIM Consensus Statement on the Treatment of Immune Thrombocytopenia.

The First Records of Canine Babesiosis in Dogs from Dermacentor reticulatus-Free Zone in Poland

Tick-borne microorganisms belong to important etiological agents of many infectious diseases affecting humans and animals. Among them, there are haemoprotozoans of the Babesia genus, which infect erythrocytes of a host and may cause many clinical symptoms. Canine babesiosis is an emerging tick-borne disease in Southern and Central Europe. In this study, we report two cases of symptomatic canine babesiosis caused by Babesia canis in domestic dogs from the Silesian Voivodeship, Poland, as well as the presence of Dermacentor reticulatus ticks detected on one of the Babesia-infected dogs (D. reticulatus-free zone). The molecular analysis confirmed the presence of Babesia canis in the dogs’ blood, and the sequencing analysis showed that the obtained sequence is 100% identical to the sequence of Babesia canis isolate 3469 (sequence ID: KX712122.1). Our findings should raise awareness of B. canis infection among dog owners and veterinarians in the region where B. canis was not previously reported in residential, non-traveling dogs, as well as ensuring that adequate diagnostic methods are available.

High Asymptomatic Cases of Babesiosis in Dogs and Comparison of Diagnostic Performance of Conventional PCR vs Blood Smears

PURPOSE

Babesiosis is one of the most important globally extended and quickly spreading tick-borne infections of dogs. Diagnosis of babesiosis in Sri Lanka is based on clinical signs followed by thin blood smears which could be error-prone due to undetected early infections, absence of clinical signs or low parasitemia. The present study investigated the prevalence of babesiosis in dogs presented to the Veterinary Teaching Hospital (VTH) at the Faculty of Veterinary Medicine and Animal Science, University of Peradeniya, for treatments, vaccinations, and regular check-ups, and compared the diagnosis methods of microscopy and molecular analysis.

METHODS

Blood samples from dogs were collected from January to June 2019. First, Giemsa stained blood smears were prepared, and then the blood samples were subjected to PCR using genus-specific primers to amplify a 411-450 bp region in the 18S rRNA gene. Twenty samples from PCR amplified products were sequenced for species identification and phylogenetic analysis. Clinical signs of the dogs were noted down, and ticks were also collected from dogs if any.

RESULTS

Results show a very high prevalence of canine babesiosis (78.6%) among the dogs brought to the VTH. The parasite was identified microscopically and genetically as Babesia gibsoni. A large percentage (66.7%) of infections was asymptomatic. Out of 42 blood samples, 19 (45.2%) were microscopically positive for babesiosis while 33 (78.6%) were PCR positive, showing a significant difference in the two methods of diagnosis (chi-square test, χ² = 9.462, p = 0.002). Three tick species: Rhipicephalus haemaphysaloides, Haemaphysalis bispinosa, and Rhipicephalus sanguineus were found attached to the dogs.

CONCLUSION

This study shows a very high prevalence of canine babesiosis among dogs in the Kandy area. Most of these infections might go undetected if only microscopy was used to diagnose. An improved, rapid diagnostic method such as the novel, PCR-based point-of-care diagnostic method that detects very low parasitemia within 30 min is needed. Moreover, as most infected dogs did not show clinical signs, they may act as reservoirs of infection. The ability of asymptomatic dogs to spread babesiosis should be investigated.