Comparison of clinical and imaging findings in cats with single and mixed lungworm infection

Abstract

Objectives This study has compared clinical and imaging features in 52 cats naturally infected by respiratory nematodes Aelurostrongylus abstrusus, Troglostrongylus brevior and Capillaria aerophila, and in both monospecific and mixed infections. Methods Medical records of cats with a lungworm disease were retrospectively reviewed. Cats with clinical examination findings, haematobiochemical analysis and thoracic radiography were included in the study and clinical and radiographic scores were assigned. For eight cats CT of the thorax was also available and analysed. A statistical analysis was performed to investigate the potential correlation between clinical and radiographic score, and to evaluate the effect of age, sex and infection on clinical and radiographic severity. Results Monospecific infections by A abstrusus (32/52), T brevior (6/52) and C aerophila (5/52) and coinfectionsby T brevior/ A abstrusus (7/52), T brevior/ C aerophila (1/52) and A abstrusus/ C aerophila (1/52) were diagnosed. Cats with mixed infections showed higher clinical scores compared with cats with monospecific parasitoses ( P <0.05), while no differences were observed for radiographic scores. No correlation between clinical and radiographic scores was found (r = 0.50), and these scores were not affected by patient age or sex. CT, performed on cats infected with A abstrusus, T brevior or A abstrusus/T brevior, provided additional information in cats with mild radiographic signs. Conclusions and relevance This study indicates that clinical parameters may be more severe in mixed infections than in monospecific parasitoses. A significant correlation between clinical and radiographic score was not detected, while several subclinically infected cats showed radiographic changes. In cats with mild-to-moderate lung patterns, the ventrodorsal/dorsoventral projection showed lesions that are not visible in the lateral projections, especially in the caudal lobes.

Controlled field study evaluating the clinical efficacy of a topical formulation containing emodepside and praziquantel in the treatment of natural cat aelurostrongylosis

“…The cats underwent a complete clinical examination, with a thorough history, retroviral status (SNAP Feline Immunodeficiency Virus/Feline Leukaemia Virus Combo Test, IDEXX Laboratories), two orthogonal thoracic radiographs, Baermann test and PCRs from faeces and pharyngeal swabs. Clinical scores (CS) and a radiographic scores (RS) were assessed for each cat, as previously described 10. For each clinical sign (ie, food intake, activity, cough, mucous membranes, rectal temperature, ocular and/or nasal discharge, respiratory rate, respiratory movements, auscultations) 0 to 2 points were assigned, and 0 to 3 points were assigned for each radiographic alteration (ie, bronchial, alveolar, nodular interstitial, reticular interstitial).…”

“…Clinical scores (CS) and a radiographic scores (RS) were assessed for each cat, as previously described. 10 For each clinical sign (ie, food intake, activity, cough, mucous membranes, rectal temperature, ocular and/or nasal discharge, respiratory rate, respiratory movements, auscultations) 0 to 2 points were assigned, and 0 to 3 points were assigned for each radiographic alteration (ie, bronchial, alveolar, nodular interstitial, reticular interstitial). Individual faecal samples were tested with the Baermann migration method 23 for the presence of A abstrusus L1, that were identified according to morphometric and morphological features.…”

“…Clinical signs associated with feline aelurostrongylosis are due to the inflammatory reaction in the alveoli, bronchioles and arteries, elicited by egg production and hatching and migration of first-stage larvae (L1s) within the respiratory tract 7 8. Clinical manifestations are variable: some animals are subclinically infected9 10 or, more often, they present with prevailing respiratory and non-specific signs such as cough, dyspnoea, tachypnoea, sneezing, lethargy and weight loss 3 4 11. Also, auscultation of the thorax usually reveals increased vesicular breath sounds, wheezing or crackles 12.…”

“…Thoracic radiography often reveals a pulmonary interstitial and bronchial infiltrative pattern, with alveolar and nodular patterns being less common. Thoracic radiography and findings depend on the stage of infection, infection dose and the stage of the disease, with radiographic alterations in apparently healthy but infected cats and a possible lack of radiographic lesions in the presence of overt clinical signs 10 17…”

“…Thoracic radiography and findings depend on the stage of infection, infection dose and the stage of the disease, with radiographic alterations in apparently healthy but infected cats and a possible lack of radiographic lesions in the presence of overt clinical signs. 10 17 …”