Occurrence, diagnosis and follow-up of canine strongyloidiosis in naturally infected shelter dogs.

Strongyloidiosis by Strongyloides stercoralis is a disease of increasing interest in human and animal medicine. The scientific knowledge on canine strongyloidiosis is hindered by the poor diagnostics available. To assess the most sensitive and specific diagnostic method, feces and blood from 100 shelter dogs were screened for S. stercoralis by coprological, molecular and serological tests. Thirty-six dogs (36%) scored positive to S. stercoralis by coprology (22.3% to Baermann) and/or 30% to real time-polymerase chain reaction (rt-PCR). According to two composite reference standards (CRS) based on all coprological methods and rt-PCR (first CRS) or in combination with serology (second CRS), the most sensitive test was IFAT (93.8%; CI 82.8-98.7), followed by rt-PCR (80.6%; 95% CI 64-91.8) and Baermann (60.6%; 95% CI 42.1-77.1). The inconsistent shedding of L1 during the 4-week follow-up in infected dogs suggests the importance of multiple faecal collections for a reliable diagnosis. A combination of serological and coprological tests is recommended for the surveillance and diagnosis of S. stercoralis infection in dogs.

Canine angiostrongylosis in naturally infected dogs: clinical approach and monitoring of infection after treatment.

Canine angiostrongylosis is an increasingly reported disease in Europe which can be fatal if left untreated. The wide range of clinical presentation along with the absence of pathognomonic alterations can make the diagnosis challenging; thus any additional information that may provide clues to an early diagnosis may be of value, in order to ensure adequate anthelmintic treatment. Aim of the study was to assess a clinicopathological scoring system associated with natural Angiostrongylus vasorum infection diagnosed in canine patients during clinical practice, to clinically and paraclinically monitor infected dogs after treatment, and to monitor the presence of L1 larvae in faecal samples by Baermann's test. Of the total 210 enrolled animals A. vasorum infection was diagnosed in 7 dogs. These dogs were clinically and paraclinically investigated and monitored after specific treatment. Further 3 symptomatic dogs were retrospectively included in the monitoring. Results suggest that the computed scoring system can help to increase the clinical suspicion of infection particularly in asymptomatic dogs before the onset of potentially lethal lesions. Data of faecal monitoring suggested that treatment may control parasite burden but be unable to eradicate infection. Thus, a continued faecal monitoring after treatment is advisable for identification of still infected or reinfected dogs.

Is Pulmonary Hypertension a Rare Condition Associated to Angiostrongylosis in Naturally Infected Dogs?

Canine angiostrongylosis due to Angiostrongylus vasorum is one of the cardiopulmonary parasitic diseases in dogs and it can manifest with very different clinical pictures, which often make diagnosis very difficult. Based on the nature of the vascular and parenchymal lesions induced by the infection (thrombo-arteritis and fibrosis), it is not surprising that cases of pulmonary arterial hypertension (PAH) associated with angiostrongylosis have been reported in the literature, although it seems to represent a rare condition. The aim of the present work is to describe the clinical and instrumental aspects referred to cases of canine angiostrongylosis before and after treatment then to evaluate even mild conditions of PAH using echocardiography. PAH was not only conventionally investigated based on characteristic cardiac changes that occur secondary to PAH and by estimating pulmonary pressure from spectral Doppler tracings, but also by using a combination of further selected echocardiographic parameters (AT/ET, PA/Ao, Pulmonary flow profile pattern) able also to reveal PAH in the absence of tricuspid or pulmonary regurgitation. Clinical and instrumental aspects of 17 cases of angiostrongylosis, divided into respiratory cases (n = 6), nonrespiratory (n = 5), and asymptomatic (n = 6), are here described. Radiographic alterations were recorded in 90% of patients despite the reason for clinical presentation. A state of mild to severe PAH was diagnosed in 58.8% of cases. Although the return to a normal clinical condition was achieved 2 months after treatment in almost all patients, radiographic and echocardiographic alterations were persistent for longer. The cases presented reinforce the evidence on the complexity of the clinical picture of angiostrongylosis. PAH associated with canine angiostrongylosis could be a more common condition than previously reported in naturally infected dogs. In some cases, echocardiographic findings suggestive of PAH could be the starting point to address the clinical diagnosis toward angiostrongylosis. PAH may be responsible for worsening of the clinical picture of patients; thus, a careful evaluation is suggested before and after anthelmintic treatment in order to optimize the therapeutic management of each case.

Efficacy of ivermectin to control Strongyloides stercoralis infection in sheltered dogs.

In dogs, information on treatments against S. stercoralis infection is rare and anecdotal. The aim of the present work was to evaluate the treatment outcome of S. stercoralis natural infection in sheltered dogs. Furthermore, based on the potential risk of infection, people working in the infected shelter were also tested. Seventeen sheltered dogs positive to S. stercoralis using the Baermann test were treated with ivermectin 200 µg/kg/sid/os for two consecutive days. Only two dogs showed clinical signs suggestive of strongyloidiasis (diarrhea, weigh loss) at diagnosis. All dogs showed consistently negative results for S. stercoralis at weekly monitoring after treatment using both the direct microscopy and Baermann test. Real-time PCR confirmed negative results at the last follow up 2 months after treatment. Serology performed at the first diagnosis showed that 82% and 41% of dogs were positive for S. stercoralis using an IFAT (titres ranging from 1:40 to 1:320) and ELISA, respectively. Two months after treatment, IFAT titres were strongly reduced in all animals. The results of clinical pathological laboratory tests at diagnosis in the positive dogs were within normal ranges, except for the two symptomatic dogs. Serum collected from two out of 14 shelter workers tested positive with titres 1:20 and 1:40 for S. stercoralis using an IFAT. Results of the study confirm that ivermectin was an effective treatment option to control S. stercoralis infection in dogs. Shelter workers are at risk of infection with S. stercoralis, thus the application of correct deworming protocols to reduce the environmental infective larval burden is essential to protect dogs and probably also shelter workers from the risk of infection.

Occurrence of strongyloidiasis in privately owned and sheltered dogs: clinical presentation and treatment outcome.

BACKGROUND: The increasing number of reports of human infections by Strongyloides stercoralis from a range of European countries over the last 20 years has spurred the interest of the scientific community towards this parasite and, in particular, towards the role that infections of canine hosts may play in the epidemiology of human disease. Data on the epidemiology of canine strongyloidiasis is currently limited, most likely because of the inherent limitations of current diagnostic methods. METHODS: Faecal samples were collected directly from the rectal ampulla of 272 animals of varying age and both genders living in Apulia, southern Italy. Dogs included were either privately owned (n = 210), living in an urban area but with unrestricted outdoor access (Group 1), or shelter dogs (n = 62 out of ~400) hosted in a single shelter in the province of Bari in which a history of diarrhoea, weight loss, reduced appetite and respiratory symptoms had been reported (Group 2). Strongyloides stercoralis infection was diagnosed by coproscopy on direct faecal smear and via the Baermann method. RESULTS: Six of 272 dogs were positive for S. stercoralis at the Baermann examination; all but one were from the shelter (Group 2) and displayed gastrointestinal clinical signs. The only owned dog (Group 1) infected with S. stercoralis, but clinically healthy, had been adopted from a shelter 1 year prior to sampling. Five infected dogs were treated with fenbendazole (Panacur®, Intervet, Animal Health, 50 mg/kg, PO daily for 5 days), or with a combination of fenbendazole and moxidectin plus imidacloprid spot-on (Im/Mox; Advocate® spot-on, Bayer). Post-treatment clearance of infection was confirmed in three dogs by Baermann examination, whereas treatment failure was documented in two dogs by Baermann and/or post-mortem detection of adult parasites. CONCLUSIONS: This study describes, for the first time, the presence of S. stercoralis infection in sheltered dogs from southern Italy. Data indicate that S. stercoralis infection may pose a concern for sheltered animals and raise questions on potential risks of infection for staff of municipal shelters in southern European countries. Given that a single course of treatment with fenbendazole, associated or not with Im/Mox spot-on, may not eliminate the infection, effective treatment protocols should be investigated and control strategies targeting the environment considered for reducing the risk of zoonotic infection.