Abstract
Dirofilaria immitis is a nematode that can cause a disease that may present clinical signs from severe to absent. When dogs are symptomatic, the clinical signs are cardiorespiratory and nonspecific, which may be misleading. This study aimed to demonstrate the clinical presentations to cardiac care by evaluating 26 dogs subjected to clinical examination, complete blood count (CBC), specific tests for D. immitis infection, chest radiography, and echocardiography. Among them, 11 (42.3%) dogs were infected and 15 (57.7%) were non-infected. Most dogs presented with coughing (65.4%) and abnormal lung sounds (81%) independent of infection. Murmur at the tricuspid focus was present in 26.9% of the dogs, of which 57.1% were infected. Echocardiography revealed tricuspid regurgitation in 30.8% of the dogs and pulmonary regurgitation in 46.1%, of which 37.5% and 50% were infected, respectively. Worms were detected by echocardiography in 45.5% of the infected dogs. The x-rays showed that the bronchial pattern was present in 45.5% of the infected dogs and in 46.7% of the non-infected dogs. The interstitial pattern was present in 18.2% of the infected animals, in contrast to 6.7% of the non-infected dogs. The CBC results for all dogs were within the reference range, except for platelets. Although similar, the percentage of dogs with thrombocytopenia was higher among infected dogs (36.4%) than among the non-infected (6.7%). These results reinforce that due to the non-specific signs of infection, it is mandatory to perform parasitological assays when evaluating dogs presenting with cardiopulmonary signs.
References
American Heartworm Society. (2020). Current Canine Guidelines for the Prevention, Diagnosis, and Management of Heartworm (Dirofilaria immitis) Infection in Dogs. American Heartworm Society. https://www.heartwormsociety. org/images/pdf/2018-AHS-Canine-Guidelines.pdf
Alberigi, B., Fernandes, J., Paiva, J. P., Mendes-de-Almeida, F., Knackfuss, F., Merlo, A., & Labarthe, N. (2020). Efficacy of semi-annual therapy of na extended-release injectable moxidectin suspension and oral doxycycline in Dirofilaria immitis naturally infected dogs. Parasites & Vectors, 13(1), 1-8. http://dx.doi.org/10.1186/ s13071-020-04380-z.
Bandi, C., Trees, A. J., & Brattig, N. W. (2001). Wolbachia in filarial nematodes: Evolutionary aspects and implications for the pathogenesis and treatment of filarial diseases. Veterinary Parasitology, 98(1-3), 215-238. http://dx.doi.org/10.1016/S0304-4017(01)00432-0. PMid:11516587.
Boon, J. A. (2011). Veterinary Ehocardiography (2nd ed.). John Wiley & Sons.
Calvert, C. A., & Thomason, J. D. (2008). Heartworm Disease. In L. Tilley, F. Smith, M. Oyama, & M. Sleeper. Manual of Canine and Feline Cardiology (4th ed., pp. 183-199). W.B.Saunderes. http://dx.doi.org/10.1016/ B978-141602398-2.10010-5.
Calvert, C. A., & Rawlings, C. A. (2002). Dirofilariose canina. In L. P. Tilley, & J. K. Goodwin. Manual de Cardiología para Cães e Gatos (3rd ed., pp. 223-227). Roca.
Calvert, C. A. & Rawlings, C. A. (1983). Diagnosis and management of canine heartworm disease. In R. W. Kirk. Current Veterinary Therapy VIII (pp. 348-359). W.B. Saunders
European Society of Dirofilariosis and Angiostrongylosis. (2017). Guidelines for clinical management of canine heartworm disease. ESDA. https://www.esda.vet/media/attachments/2021/08/19/canine-heartworm-disease.pdf
Feitosa, F. L. (2020). Introdução à semiologia. In F. L. Feitosa. Semiologia Veterinária a Arte do Diagnóstico (3rd ed., pp. 1-24). Roca.
Gompf, R. (2008). The history and Physical Examination. In L. Tilley, F. Smith, M. Oyama, & M. Sleeper. Manual of Canine and Feline Cardiology (4th ed., pp. 2-23). Saunders. http://dx.doi.org/10.1016/B978-141602398-2.10001-4.
Guerrero, J. (2005). Heartworm pathophysiology in dogs and cats. In Proceedings of the 30th Congress of the World Small Animal Association. World Small Animal Veterinary Association.
Jain, N. C. (1993). Essentials of Veterinary Hematology. Lea e Febiger.
Jessup, M., Sutton, M. S. J., Weber, K. T., & Janicki, J. S. (1987). The effect of chronic pulmonary hypertension on left ventricular size, function, and interventricular septal motion. American Heart Journal, 113(5), 1114-1122. http://dx.doi.org/10.1016/0002-8703(87)90921-5. PMid:3578005.
Keene, B. W., Atkins, C., Bonagura, J., Fox, P., Gordon, S., Haggstrom, J., Luis-Fuentes, V., Oyama, M. A., Rush, J. E., Stepien, R., & Uechi, M. (2019). ACVIM consensus guidelines for the diagnosis and treatment of myxomatous mitral valve disease in dogs. Journal of Veterinary Internal Medicine 33(3), 1127-1140. http://dx.doi.org/10.1111/jvim.15488. PMid:30974015.
Knight, D. H. (1987). Heartworm infection. The Veterinary Clinics of North America. Small Animal Practice, 17(6), 1463-1518. http://dx.doi.org/10.1016/S0195-5616(87)50012-2. PMid:3328398.
Labarthe, N., Paiva, J., & Campos, J. (2009). Dirofilariose. In C. B. Marcondes. Doenças Transmitidas e causadas por artrópodes (1st ed., pp. 283-299). Ateneu.
MacNee, W. (1994). Pathophysiology of cor pulmonale in chronic obstructive pulmonary disease. Part two. American Journal of Respiratory and Critical Care Medicine, 150(4), 1158-1168. http://dx.doi.org/10.1164/ ajrccm.150.4.7921453. PMid:7921453.
Madron, E. (2016). Dirofilariais: Specific Bidimensional Aspects. In V. Chetboul, C. Bussadori & E. Madron. Clinical Echocardiography of the Dog and Cat (1st ed., pp. 241-243). Elsevier.
Maggiore, A. D. (2014). Tracheal and airway collapse in dogs. Veterinary Clinics: Small Animal Practice, 44(1), 117-127. PMid:24268337.
McCall, J. W., Genchi, C., Kramer, L. H., Guerrero, J., & Venco, L. (2008). Heartworm disease in animals and humans. Advances in Parasitology, 66(1), 193-285. http://dx.doi.org/10.1016/S0065-308X(08)00204-2. PMid:18486691.
McHaffie, J. (2012). Dirofilaria immitis and Wolbachia pipientis: A thorough investigation of the symbiosis responsible for canine heartworm disease. Parasitology Research, 110(2), 499-502. http://dx.doi.org/10.1007/ s00436-011-2644-5. PMid:21922235.
Montoya-Alonso, J. A. (2007). Enfermidades respiratórias em pequenos animais. Interbook.
Newton, W. L., & Wright, W. H. (1956). The occurrence of a dog filariid other than Dirofilaria immitis in the United States. The Journal of Parasitology, 42(3), 246-258. http://dx.doi.org/10.2307/3274849. PMid:13332492.
Nishimura, R. A., & Tajik, A. J. (1997). Evaluation of diastolic filling of left ventricle in health and disease: Doppler echocardiography is the clinician’s Rosetta Stone. Journal of the American College of Cardiology, 30(1), 8-18. http://dx.doi.org/10.1016/S0735-1097(97)00144-7. PMid:9207615.
Niwetpathomwat, A., Kaewthamasorn, M., Tiawsirisup, S., Techangamsuwan, S., & Suvarnvibhaja, S. (2007). A retrospective study of the clinical hematology and the serum biochemistry tests made on canine dirofilariasis cases in an animal hospital population in Bangkok, Thailand. Research in Veterinary Science, 82(3), 364-369. http://dx.doi.org/10.1016/j.rvsc.2006.09.002. PMid:17095027.
Polizopoulou, Z. S., Koutinas, A. F., Saridomichelakis, M. N., Patsikas, M. N., Leontidis, L. S., Roubies, N. A., & Desiris, A. K. (2000). Clinical and laboratory observations in 91 dogs infected with Dirofilaria immitis in northern Greece. The Veterinary Record, 146(16), 466-469. http://dx.doi.org/10.1136/vr.146.16.466. PMid:10819132.
Rawlings, C. A. (1986). Heartworm Disease in Dogs and Cats (1st ed.). Saunders.
Reinero, C., Visser, L. C., Kellihan, H. B., Masseau, I., Rozanski, E., Clercx, C., Williams, K., Abbott, J., Borgarelli, M., & Scansen, B. A. (2020). ACVIM consensus statement guidelines for the diagnosis, classification, treatment, and monitoring of pulmonary hypertension in dogs. Journal of Veterinary Internal Medicine, 34(2), 549-573. http://dx.doi.org/10.1111/jvim.15725. PMid:32065428.
Render, M. L., Weinstein, A. S., & Blaustein, A. S. (1995). Left ventricular dysfunction in deteriorating patients with chronic obstructive pulmonary disease. Chest, 107(1), 162-168. http://dx.doi.org/10.1378/chest.107.1.162. PMid:7813269.
Simón, F., Siles-Lucas, M., Morchon, R., Gonzalez-Miguel, J., Mellado, I., Carreton, E., & Montoya-Alonso, J. A. (2012). Human and animal dirofilariasis: The emergence of a zoonotic mosaic. Clinical Microbiology Reviews, 25(3), 507-544. http://dx.doi.org/10.1128/CMR.00012-12. PMid:22763636.
Thrall, D. E. (2013). Practical approach to obtaining and interpreting thoracic radiographs in dogs, with emphasis on heartworm disease and its mimics. American Heartworm Society 14th Triennial Symposium.
Tilley, L. P., & Goodwin, J. K. (2002). Manual de Cardiologia para Cães e Gatos (3rd ed., pp. 489). Roca.
Venco, L., Manzocchi, S., Genchi, M., & Kramer, L. H. (2017). Heat treatment and false-positive heartworm antigen testing in ex vivo parasites and dogs naturally infected by Dirofilaria repens and Angiostrongylus vasorum. Parasites & Vectors, 10(Suppl 2), 476. http://dx.doi.org/10.1186/s13071-017-2444-6. PMid:29143662.
Venco, L. (2005). Heartworm (Dirofilaria immitis) disease in dogs. In Genchi, C., Rinaldi, L., & Cringoli, G. Dirofilaria immitis and D. repens in dog and cat and human infections (pp. 117-125). Rolando Editore.
Venco, L., Genchi, C., Vigevani Colson, P., & Kramer, L. (2003). Relative utility of echocardiography, radiography, serologic testing and microfilariae counts to predict adult worm burden in dogs naturally infected with heartworms. Recent Advances in Heartworm Disease, Symposium, (Vol. 1, pp. 111-24).
This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright (c) 2022 Nathália Marques De Oliveira Lemos , Bruno Alberigi , Norma Labarthe, Fabiana Batalha Knacfuss, Cristiane Divan Baldani, Marta Fernanda Albuquerque da Silva