Unusual cause of unilateral facial oedema: intramuscular dirofilariasis.

INTRODUCTION: Unilateral facial oedema may occur due to inflammatory, infective, or cystic pathology; patients often seek medical help at an early stage. CASE REPORT: We report one such case caused mimicking a parotid abscess, caused by dirofilariasis. CONCLUSION: Dirofilariasis is an emerging zoonosis and should be considered a differential diagnosis of atypical facial swelling. It is equally important for clinicians, radiologists, and pathologists to be familiar with the diagnostic characteristics to avoid misdiagnosis.

Angiogenesis in cardiopulmonary dirofilariosis: does the Wolbachia surface protein have a pro- or anti-angiogenic effect?

Cardiopulmonary dirofilariosis caused by Dirofilaria immitis produces inflammation, blood vessel obstruction and hypoxia, which are required conditions for the beginning of the process of neovascularization. Since D. immitis harbours intracellular symbiotic Wolbachia bacterium, the global understanding of the angiogenic process requires the analysis of the effect of the parasite molecules, but also that of Wolbachia. Canine primary lung microvascular endothelial cells were treated with the recombinant Wolbachia surface protein (rWSP) and the expression of angiogenic factors like Vascular Endothelial Growth Factor-A (VEGF-A), sFlt, membrane Endoglin (mEndoglin) and soluble Endoglin (sEndoglin), as well as the in vitro formation of pseudocapillaries, were measured. The analyses showed a significant increase in the expression of pro-angiogenic VEGF-A and anti-angiogenic sEndoglin, together with a significant decrease in both pro-angiogenic mEndoglin and pseudocapillary formation, compared to untreated controls. Due to the complexity of the angiogenic process and its relationship with other physiological processes like inflammation and fibrinolysis, these results might suggest that rWSP participate in various mechanisms related to each other and its effects might depend either on the balance between them or on the moment of their occurrence.

Multidetector computed tomographic pulmonary angiography in a cat with fatal heartworm disease.

A 17-month-old neutered male domestic shorthair cat was referred for a computed tomographic (CT) study of the thorax due to respiratory distress. Multidetector CT angiography showed a multifocal interstitial ground glass opacity, tortuous and blunted pulmonary arteries consistent with thromboembolism with perivascular lung infiltration and hypoventilation in multiple lung lobes. A blood antigen test was positive for Dirofilaria immitis. The cat's clinical condition rapidly declined and the owners elected euthanasia. The histopathologic examination confirmed heartworm disease with parasitic pulmonary thromboembolism.

Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections in stray and pet cats (Felis catus) in northwest China: co-infections and risk factors.

This study was conducted to estimate the prevalence of Toxoplasma gondii, Dirofilaria immitis, feline immunodeficiency virus (FIV), and feline leukemia virus (FeLV) infections among stray and pet cats in Lanzhou, northwest China, and to identify the influence of age, gender, and regions on seropositivity. T. gondii antibodies were examined in cat sera by the modified agglutination test (MAT). The circulating antigens of D. immitis and FeLV and specific antibodies to FIV were examined using kits commercially available. The overall prevalence of T. gondii, FIV, FeLV, and D. immitis was 19.34, 9.12, 11.33, and 3.04 %, respectively. For the genetic characterization of T. gondii genotypes in cats, genomic DNA was extracted from the seropositive cats and the T. gondii B1 gene was amplified using a semi-nested PCR. DNA samples giving positive B1 amplification were then genotyped using multilocus PCR-RFLP. Two T. gondii genotypes (ToxoDB#9 and ToxoDB#1) were identified. Results of the multivariate logistic regression analysis showed that older cats are more likely to be seropositive than juveniles for T. gondii, FIV, FeLV, and D. immitis. This is the first report of T. gondii genotypes in cats in northwest China. Moreover, the present study is the first study of retrovirus and D. immitis seroprevalence in cats in China. The results revealed that T. gondii, FIV, and FeLV infections are common in stray and pet cats in northwest China.

Aberrant heartworm migration to the abdominal aorta and systemic arteriolitis in a dog presenting with vomiting and hemorrhagic diarrhea.

A 2-year-old Dachshund was presented for vomiting and diarrhea. Abdominal ultrasound revealed Dirofilaria immitis in the abdominal aorta and an avascular segment of small intestine. The dog was euthanized. Necropsy revealed D. immitis in the abdominal aorta and widespread necrotizing arteriolitis. This is a unique presentation of aberrant migration of D. immitis.

Migration aberrante du ver du cœur vers l'aorte abdominale et artériolite systémique chez un chien présentant des vomissements et une diarrhée hémorragique. Un Dachshund âgé de 2 ans a été présenté pour des vomissements et de la diarrhée. Une échographie de l'abdomen a révélé Dirofilaria immitis dans l'aorte abdominale et un segment avasculaire du petit intestin. Le chien a été euthanasié. La nécropsie a révélé D. immitis dans l'aorte abdominale et une artériolite nécrosante généralisée. Il s'agit d'une présentation unique de la migration aberrante de D. immitis.(Traduit par Isabelle Vallières).

Dirofilaria immitis and Angiostrongylus vasorum: the contemporaneous detection in kennels.

BACKGROUND: The cardiopulmonary nematodes Dirofilaria immitis and Angiostrongylus vasorum are increasingly reported in dogs and are responsible for two diseases with overlapping endemic areas, especially in Europe: dirofilariosis and angiostrongylosis. The reasons for their apparent emergence are unknown, but several factors (e.g. increased disease awareness, better diagnostic tools, climatic changes, seasonal population dynamics and movements of animals) may play a role in the recent rise in reports of infection in the various countries of Europe. The aim of this study was to investigate the seroprevalence of D. immitis (by DiroCHECK® ELISA) and the fecal presence of first stage larvae (L1) of A. vasorum (by FLOTAC) in dogs from 68 kennels of the Campania region (southern Italy). The fecal samples were collected from pooled samples using the box as epidemiological unit. To the authors's knowledge, this is the first cross-sectional survey conducted at regional-scale in Italy and in Europe on the contemporaneous detection of D. immitis antigens and A. vasorum L1 in kennels. RESULTS: Antigens of D. immitis were detected in 24/537 (4.4%; 95% Confidence Interval = 3.0-6.7) dogs in 6 out of the 68 kennels (8.8%; 95% CI = 3.6-18.9). The 24 positive samples for D. immitis antigen were tested also with AngioDetect® and only 1 sample was seropositive for A. vasorum with a prevalence of 4.2%. A. vasorum L1 were detected in dogs from 9 out of the 68 kennels (13.2%; 95% CI = 21.8-44.9). Pooled fecal samples from 25 boxes out of the 1360 analyzed resulted positive to A. vasorum L1 (1.8%; 95% CI = 1.2-2.7). CONCLUSIONS: The present study indicates that cardiopulmonary nematodes are present in Campania region in symptomatic dogs as well as in asymptomatic ones. Therefore, regular parasitological surveillance, appropriate treatment strategies and high quality standard of hygiene are required to guarantee the health and welfare of kennel dogs.

Dirofilaria presenting as orbital mass.

Dirofilaria is a common roundworm infection of dogs, cats, raccoons, and other animals that is commonly referred to as "heartworm." The genus Dirofilaria includes D. immitis, which is a common cause of animal disease in the western hemisphere and primarily manifests as pulmonary lesions in humans, and D. repens, which is the more common causative agent of animal disease in Eurasia and primarily results in subcutaneous and ocular lesions in humans. Humans are accidental end hosts, with infection resulting from bites by mosquitoes of the Culicidae family in which ingested microfilaria have matured to infectious larvae.

Spontaneous pneumothorax in a dog with a history of successfully treated heartworm disease: A case report.

OBJECTIVE: To describe a dog presented with spontaneous pneumothorax secondary to chronic pulmonary changes associated with a history of resolved canine heartworm disease. CASE OR SERIES SUMMARY: A 7-year-old 25.2kg female spayed German Shepherd mix was presented for management of spontaneous pneumothorax. The dog had a history of heartworm disease that underwent therapy prior to adoption, and the dog was heartworm antigen negative (SNAP 4Dx) during hospitalization for the pneumothorax. An exploratory thoracotomy was performed due to an unresolving pneumothorax requiring multiple thoracocenteses. Perioperatively, the lungs did not expand with positive pressure ventilation and diffuse, multifocal to coalescing areas of darkened tissue that were grossly consistent with necrosis and/or hemorrhage were noted. The dog was euthanized intraoperatively due to an assumed poor prognosis. Histopathologic examination findings were consistent with chronic reactive changes related to previous heartworm infection. No neoplastic or infectious etiologies were identified. NEW OR UNIQUE INFORMATION PROVIDED: Spontaneous pneumothorax is a known complication of active heartworm infection. However, this case represents the first report of spontaneous pneumothorax secondary to chronic pulmonary changes caused by resolved heartworm infection.

Human pulmonary dirofilariasis coexisting with intercostal neurilemmoma: a case report and literature review.

Human pulmonary dirofilariasis (HPD) is a rare zoonotic infection caused by Dirofilaria immitis. Dogs are the definite hosts and humans are infected occasionally via a vector, generally a mosquito. Most thoracic neurilemmoma arise in the mediastinum and fewer tumors originate peripherally from the intercostal nerves. Most patients with HPD or thoracic neurilemmoma are asymptomatic and these diseases are often discovered incidentally. We present a 53-year-old female who was found to have a pulmonary nodule and a chest wall nodule during a routine health examination. She underwent a video-assisted thoracoscopic surgery (VATS) with partial lung resection and local excision of the chest wall. The pathological examination revealed a coiled, degenerating Dirofilariasis immitis worm surrounded by granulomatous inflammation with caseous necrosis and a neurilemmoma composed of S-100 protein immunoreactive but smooth muscle actin negative spindle cells. Because these diseases are self-limiting and make further treatment unnecessary, video-assisted thoracoscopic surgery (VATS) is considered preferable and less invasive for definitive diagnosis and management.

Albuminuria and proteinuria in dogs infected with Dirofilaria repens: A cross-sectional study.

BACKGROUND: It is unknown whether Dirofilaria repens is capable of causing similar glomerular lesions, as does Dirofilaria immitis. OBJECTIVE: To determine whether D. repens infection could cause albuminuria or proteinuria. ANIMALS: Sixty-five clinically healthy laboratory beagle dogs. METHODS: In this cross-sectional study, dogs were tested for D. repens infection (modified Knott test, PCR test, D. immitis antigen test) and were grouped as "D. repens infected" or "control" dogs. Urinary albumin-to-creatinine ratio (UAC) and urinary protein-to-creatinine ratio (UPC) were measured from samples taken by cystocentesis. RESULTS: Forty-three (26 infected, 17 control) dogs were included in the final study group. UAC but not UPC level was significantly higher in the infected group (UAC median 12.5; range, 0-700 mg/g and UPC median 0.15; range, 0.06-1.06) than in the control group (UAC median 6.3; range, 0-28 mg/g and UPC median 0.13; range, 0.05-0.64; P = .02 and P = .65). Overt proteinuria (UPC > 0.5) was present in 6/26 (23%) of the infected dogs and 1/17 (6%) of the control dogs. Albuminuria (UAC > 19 mg/g) was detected in 9/26 (35%) dogs in the infected group, and 2/17 dogs (12%) in the control group. CONCLUSIONS AND CLINICAL IMPORTANCE: D. repens might cause similar glomerular lesions to those caused by D. immitis.

Diagnostic Accuracy of a Point-of-Care Immunoassay for Feline Immunodeficiency Virus Antibodies, Feline Leukemia Virus Antigen, and Dirofilaria immitis Antigen.

Feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) are retroviral infections of cats worldwide whose clinical manifestations range from mild to severe disease. In both cases, infected cats can live a long life with proper care and should be managed to prevent infection of other cats. Dirofilaria immitis, the nematode that causes heartworm disease, can infect cats in any region where dogs are infected. Though cats are more resistant to infection, clinical diseases in the form of heartworm-associated respiratory disease can cause death. Screening for these infectious diseases enables veterinarians to manage their cases and prevent the spread to other cats. We describe the diagnostic accuracy of a point-of-care immunoassay for FIV, FeLV, and heartworm, compared to reference methods commonly available through reference laboratories to the practicing veterinarian. For FIV, we report 100% sensitivity (95% confidence limits (CL): 96.2-100%) and 97.8% specificity (95% CL: 95.4-99.4%). For FeLV, we report 100% sensitivity (95% CL: 97.7-100%) and 99.2% specificity (95% CL: 97.1-99.9%). And for heartworm, we report 90.2% sensitivity (95% CL: 76.9-97.3%) and 100% specificity (95% CL: 98.3-100%). Veterinarians may expect this performance relative to the reference methods they use for confirmatory serological testing.

Management and outcome of intracardiac heartworms in dogs.

BACKGROUND: Intracardiac heartworm (IH) disease is a serious condition that can become life threatening if the patient develops caval syndrome. We aim to describe the management and outcome of IH in dogs evaluated by Medvet's New Orleans cardiology service from November 2015 to December 2021. METHODS: Records of 27 dogs with IH were examined retrospectively. Follow-up information was obtained from phone conversations with referring veterinarians and owners. RESULTS: Nine of 27 dogs had a previous diagnosis of heartworm disease and were undergoing "slow kill" treatment; 12/27 dogs' heartworm disease was a new diagnosis, and 6/27 had either scheduled or started adulticide therapy. Nine dogs had heartworm extraction. No dogs died during the heartworm extraction procedure. Four of 9 dogs have died (survival time 1; 676; 1815 and 2184 days). One dog died the day after the procedure secondary to continued respiratory distress; the other three died of non-cardiac causes. Five of nine are alive (median follow-up 1062 (range 648-1831) days. Eleven dogs had IH resolution. In 7/11 this occurred while undergoing stabilization for heartworm extraction. In 4/11 heartworm extraction was not recommended because of low IH burden. All dogs with IH resolution were discharged from the hospital. Four of 11 have died (survival time 6; 22, 58 and 835 days), and 6/11 are alive (median follow-up 523 (range 268-2081) days. One was lost to follow-up after 18 days. Five dogs were medically managed. In one of five dogs, extraction was not recommended because of low IH burden. In four of five extraction was recommended but declined. One of five has died (survival 26 days), and four of five are alive (follow-up 155, 371, 935 and 947 days). Two dogs were killed at the time of diagnosis. Fifteen of 27 dogs were considered to have caval syndrome. CONCLUSION: The results suggest that patients with IH resolution have a good long-term prognosis. Most often IH resolution occurred while the dog was undergoing stabilization for heartworm extraction. When IHs are present, heartworm extraction should still be considered the treatment of choice and recommended as first-line therapy whenever possible.

Anaphylactoid reaction in a heartworm-infected dog undergoing lung lobectomy.

CASE DESCRIPTION: A 7-year-old 23-kg (50.6-lb) spayed female Border Collie with a history of heartworm disease was evaluated for respiratory distress. CLINICAL FINDINGS: Computed tomography of the thorax revealed possible pulmonary bullae or blebs, and on the basis of these findings, a tentative diagnosis of bullous emphysema was made. TREATMENT AND OUTCOME: Exploratory median sternotomy revealed gross pathological lesions in the right caudal lung lobe; the most peripheral portion appeared discolored (pale pink), and a clear line of demarcation was observed. Upon excision of the affected lung lobe, a worm segment was noticed both on the remaining stump of the lung lobe in the dog and in the removed lobe. At this time, the dog had an anaphylactoid reaction. The reaction was successfully treated with fluid therapy, antihistamines, and corticosteroids. Lung lobectomy of the right caudal lobe resulted in clinical resolution of the bilateral pneumothorax. However, during the postoperative period, the dog developed a hemothorax and was returned to surgery. As no obvious cause for the hemothorax was seen at the second surgery, the dog was treated for a potential coagulopathy with fresh frozen plasma, which provided clinical resolution of the hemothorax. Parasitological examination of the worm segment confirmed a Dirofilaria immitis infection. The dog was discharged 5 days after surgery and treated with doxycycline for 30 days and monthly administration of heartworm preventative was prescribed. CLINICAL RELEVANCE: Heartworm infection should be a differential diagnosis in dogs with spontaneous pneumothorax. Anaphylactoid reactions associated with accidental dissection of adult heartworms should be managed with treatment aimed at cardiovascular stabilization.

[Observation of dirofilariosis in the practical work of the otorhinolaryngologist].

A case of dirofilariosis is reported. The disease is believed to be caused by the contact with the cat that the patient brought in from Uzbekistan. The authors emphasize the importance of analysis of the medical history of the patients presenting with the pathology being considered, their medical examination, and correct interpretation of X-ray images of the paranasal sinuses taking into account the possibility of distribution of rare helminth species beyond their usual ranges.

A case of inguinal hernia associated with atypical Dirofilaria repens infection in a dog.

BACKGROUND: Dirofilaria repens is a filarioid nematode transmitted by mosquitoes. Adult D. repens are typically localized in the subcutaneous tissue of the host, but other, atypical localizations have also been reported. There have been several reports of clinical cases involving an association of parasites and hernias in both animals and humans. However, it is unclear if parasitic infection can act as a triggering factor in the development of hernias. METHODS: A 12-year-old dog was referred to a private veterinarian clinic in Satu Mare, northwestern Romania due to the presence of a swelling in the lateral side of the penis (inguinal area). The dog underwent hernia repair surgery during which four long nematodes were detected in the peritoneal serosa of the inguinal hernial sac. One female specimen was subjected to genomic DNA extraction to confirm species identification, based on amplification and sequencing of a 670-bp fragment of the cytochrome c oxidase subunit 1 (cox1) gene. Treatment with a single dose of imidacloprid 10% + moxidectin 2.5% (Advocate, Bayer AG) was administered. RESULTS: The nematodes were morphologically identified as adult D. repens, and the BLAST analyses revealed a 100% nucleotide similarity to a D. repens sequence isolated from a human case in Czech Republic. CONCLUSIONS: We report a case of an atypical localization of D. repens in the peritoneal cavity of a naturally infected pet dog with inguinal hernia and discuss the associations between hernia and parasitic infections.

Human pulmonary Dirofilariasis: one more case in Greece suggests that Dirofilaria is a rather common cause of coin lesions in the lungs in endemic areas of Europe.

Herein we describe a case of a 52 year-old male from Greece who presented with a coin lesion in the right lung, which proved to be an infection from Dirofilaria immitis. A careful review of the literature shows that, contrary to the common perception, humans may be frequently infected by Dirofilaria species. For this reason the authors suggest that in every case which presents with a coin lesion in the lung in endemic areas, dirofilariasis should always be considered, and excluded before any other intervention is decided.

Spontaneous pneumothorax in a dog secondary to Dirofilaria immitis infection.

A 5-year-old female spayed Labrador Retriever dog was referred to the Louisiana State University Veterinary Teaching Hospital for treatment of pneumothorax. Thoracic radiographs and computed tomography showed spontaneous pneumothorax, thoracic lymphadenopathy, pulmonary hypertension, and multifocal pulmonary bulla lesions. At surgery, numerous adult nematodes protruded from the parenchyma of the left caudal and accessory lung lobes and pulmonary arteries. On histopathology, multiple adult filarid nematodes were observed within the pulmonary blood vessels. Broad foci of necrosis of the pulmonary parenchyma were present. The tunica intima of the pulmonary arteries was markedly thickened by intimal fibrosis and medial hypertrophy. The final diagnosis was severe Dirofilaria immitis infection that resulted in pulmonary vascular lesions and focally extensive infarcts of the pulmonary parenchyma with bulla formation and rupture causing spontaneous pneumothorax. The dog received antibiotic and steroid therapy, as well as adulticide treatment, and recovered.

Unusual feline Dirofilaria immitis infection: a case report.

Cats are less susceptible to Dirofilaria immitis infection than dogs. Although rare, the feline disease can be fatal even with low parasitic loads. The infection is often asymptomatic or has non-specific symptoms that are mainly associated with the death of immature worms. Microfilaremia is rare and transient. Normally, microfilaremia, when present, lasts for not more than 33 days. This study describes a feline case presenting with non-specific clinical signs and prolonged microfilaremia. Case: a random bred cat infected by feline leukemia virus (FeLV) that was found to be microfilaremic by chance. The infection was detected by the presence of microfilariae in a blood smear and was confirmed by antigen test (SNAP Feline Triple Test, Idexx®) and echocardiogram.

Treatment of dogs with severe heartworm disease.

Fortunately, the majority of dogs diagnosed with heartworm infection are asymptomatic (or have only mild symptoms such as intermittent cough) and go through adulticide therapy without complication. Complications occurring with heartworm infection and during its treatment most often directly reflect the pulmonary vascular and parenchymal injury inflicted by Dirofilaria immitis. Clinical signs may include exercise intolerance, frequent cough, hemoptysis, tachypnea, and dyspnea. Severe manifestations such as heart failure and caval syndrome may prove fatal. Acute hypersensitivity reactions after initiation of macrocyclic lactone preventive therapy in microfilaremic dogs or after melarsomine injection during adulticide therapy do occur, but are uncommon. This article reviews complications associated with heartworm infection.