Hepatozoon canis (Canine Hepatozoonosis) - Microscopic exam and molecular diagnostics (PCR)
Hepatozoon canis is a protozoan parasite of dogs, Hepatozoon gender, family Hepatozoidae, the Apicomplexa, one of the most widespread protozoa transmitted by ticks, causing infection in dogs and wild canids. The gamonts are ellipsoidal, 11 microns x 4 microns. Hepatozoon canis is mainly located in Europe, Asia, Africa, North America and South America. In animals, infection with this parasite causes canine hepatozoonosis.
The life cycle of this microorganism involves two hosts which respectively occur in the vertebrate host merogonia intermediate (dogs or other canines), and sporogony gametogonia and the definitive host invertebrate (ticks Rhipicephalus sanguineus species). In some regions where there is no Riphicephalus anguineus, has been found in other Dermacentor marginatus ticks like, Dermacentor reticulatus and Haemaphysalis concinna. Sexual reproduction and development sporogenic occur in invertebrate definitive host, which is then ingested by the vertebrate intermediate host. In the definitive host invertebrate, the transestadio transmission occurs, i.e. it passes from the larval stage of the tick to nymph stage, and nymphal to adult. It has not been able to demonstrate transovarial transmission. Larvae or nymphs of ticks become infected by ingesting blood containing the gamonts with parasitized leukocytes. Dogs become infected by ingesting a tick oocysts containing sporozoites, but has also been demonstrated vertical transmission in dogs from mother to offspring. However, no evidence of transmission through the bite of ticks. Once in the vertebrate host, the sporozoites released oocyst cross the intestinal epithelium of the animal and parasitizes macrophages and endothelial cells, which migrate through the blood and lymphatic stream to various organs, including the spleen, bone marrow, lung , liver and kidney. In these organs, schizogony occurs. Numerous merozoites occur, some of them enter monocytes and neutrophils and become gametocitos.Cuando the invertebrate vector feeds on the blood of infected vertebrate, gametocytes present in their neutrophils or monocytes are absorbed in the gut of the invertebrate host, where they undergo gametogenesis to give oocysts and the life cycle begins again.
Canine hepatozoonosis in Europe occurs in the Mediterranean region of the Balkans in the Iberian Peninsula, in France, Portugal, Italy, Israel, among other regions, where Rhipicephalus sanguineus is frequent. In addition to the dogs, it found the infection in other canids such as the red fox (Vulpes vulpes) in the gray fox (Uroyon cynergeoargentus), golden jackal (Canis aureus), wild dogs (Lycaon pictus), coyotes (Canis latrans) , spotted hyena (crocuta crocuta), among others. Infection Hepatozoon canis not always cause disease, but subclinical infection with low levels of parasitemia, without presenting symptoms associated, unless they are immunosuppressed, present another concomitant infection, or are puppies under 3 to 4 months old. When infection coursing symptomatically can induce severe clinical manifestations as intermittent persistent fever, lethargy, anemia, cachexia, weight loss, lymphadenopathy, diarrhea, depression, generalized pain, oozing eye-nasal, anorexia, prostration, and subsequent paralysis when there is a high parasitic load. In localized infections can cause skin lesions and anterior uveitis, glaucoma, osteomyelitis, and hypertrophic osteoarthropathy Polyradiculoneuritis after systemic infection. Sometimes coinfection with other pathogens transmitted by Rhipicephalus sanguineus, Babesia vogeli, Anaplasma platys or Erhlichia canis.
Recommended tests for diagnosis:
The diagnosis is based on microscopic observation of the parasite in peripheral blood smears or extensions prepared from the buffy coat, detection of antibodies by indirect immunofluorescence methods or ELISA, either in molecular diagnostic methods (PCR). The molecular diagnostic tests Hepatozoon canis and differentiate Hepatozoon americanum.
Tests in IVAMI:
- , Preferable from the buffy coat (buffy coat). Microscopic examination
- Molecular diagnosis (PCR), to detect DNA Hepatozoon canis.
- Whole blood collected with EDTA (2 to 5 mL).
Preservation and shipment of sample:
- Refrigerated (preferred) for less than 2 days.
- Frozen: over 2 days (for molecular diagnostic tests only).
- Microscopic examination: 24 hours.
- Molecular diagnosis (PCR): 24 to 48 hours.
Cost of the test: