Computed tomographic features of feline sino-nasal and sino-orbital aspergillosis

Abstract

Makara, M. (2014). Computed tomographic features of feline sino-nasal and sino-orbital aspergillosis. Vet J. 201(2):215-22. DOI:10.1016DOI:10. /j.tvjl.2014 Computed tomographic features of feline sino-nasal and sino-orbital aspergillosis AbstractFeline upper respiratory tract aspergillosis (URTA) occurs as two distinct anatomic forms, sinonasal aspergillosis (SNA) and sino-orbital aspergillosis (SOA). An emerging pathogen, Aspergillus felis is frequently involved. The pathogenesis of URTA, in particular, the relationship between the infecting isolate and outcome, is poorly understood. Computed tomography was used to investigate the route of fungal infection and extension in 16 cases (SNA n=7, SOA n=9) where the infecting isolate had been identified by molecular testing.All cases had nasal cavity involvement except one cat with SNA that had unilateral frontal sinus changes. A strong association between the infecting species and anatomic form was identified. A. fumigatus infections remained within the sino-nasal cavity. Cryptic species infections were associated 2 | P a g e with orbital and paranasal soft-tissue involvement and with orbital lysis. These species were further associated with a mass in the nasal cavity, paranasal sinuses or nasopharynx. Orbital masses showed heterogeneous contrast enhancement, with central coalescing hypoattenuating foci and peripheral rim enhancement. Severe, cavitated turbinate lysis, typical of canine SNA, was present only in cats with SNA.These findings support that the nasal cavity is the portal of entry for fungal spores in feline URTA and that the route of extension to involve the orbit is via direct naso-orbital communication from bone lysis. Additionally, a pathogenic role for A. wyomingensis and a sinolith in a cat with A. udagawae infection are reported for the first time.

Imaging Diagnosis: Computed Tomographic Findings in a Case of Adenosquamous Carcinoma of the Head and Neck in a Cat

“…A sinonasal origin is suspected, however, as CT findings showed the epicenter of abnormal soft tissue accumulation and bony lysis to be the nasal cavity and the paranasal sinuses. In a number of retrospective studies published in the veterinary literature reporting on various aspects of feline sinonasal disease, no single case of feline sinonasal adenosquamous carcinoma was reported. In all of these studies, tumors of nonepithelial origin (comprising mostly of lymphoma) were found to be the most common feline sinonasal neoplasm; this was followed by tumors of epithelial origin (most commonly adenocarcinoma, squamous cell carcinoma, undifferentiated carcinoma) .…”

“…None of the cases of sinonasal neoplasia in these two studies were reported to involve skeletal structures outside of the sinonasal and paranasal region. In two studies focusing on fungal rhinosinusitis in cats, authors of both studies concluded there were many similarities in the CT appearance between sinonasal neoplasia and fungal rhinosinusitis. In their cases of feline fungal rhinosinusitis, common CT findings included development of a soft tissue mass in the nasal cavity, frontal sinus, sphenoid sinus, or nasopharynx; osteolysis affecting the turbinates, palatine bone, nasal septum, maxilla, orbital laminae, frontal bone, and cribriform plate; and extension of disease into paranasal and orbital tissues .…”

“…In two studies focusing on fungal rhinosinusitis in cats, authors of both studies concluded there were many similarities in the CT appearance between sinonasal neoplasia and fungal rhinosinusitis. In their cases of feline fungal rhinosinusitis, common CT findings included development of a soft tissue mass in the nasal cavity, frontal sinus, sphenoid sinus, or nasopharynx; osteolysis affecting the turbinates, palatine bone, nasal septum, maxilla, orbital laminae, frontal bone, and cribriform plate; and extension of disease into paranasal and orbital tissues . In contrast to reported cases of feline sinonasal neoplasia and fungal rhinosinusitis, the cat in this report showed diffuse and extensive lysis of the majority of the bones of the skull and aggressive periosteal new bone formation surrounding the calvaria, occipital condyles, atlas, and axis; these findings were not reported in any of the cases of feline sinonasal neoplasia or fungal rhinosinusitis in the scientific literature.…”

The current status of avian aspergillosis diagnoses: Veterinary practice to novel research avenues

“…Although aspergillosis is much less common in mammals compared with birds, similar diagnostic imaging modalities have been employed in canine patients for the diagnosis of aspergillosis, including rhinoscopy, radiography, CT, and MRI . MRI and CT use in feline patients has also been documented, and endoscopic examination of the guttural pouch and radiography have been reported in horses . As for clinical observations, definitive diagnoses by imaging is not possible, but serves as an indication that an infection is present and further analysis by more conclusive methods is required, such as identification of the microorganism using fungal cultures (Table ).…”

Feline infectious diseases: Our curiosity could be their salvation

“…New information on feline fungal infections is included, specifically in a report on a novel study that used computed tomography to investigate sino-nasal and sino-orbital aspergillosis (Barrs et al, 2014). Feline upper respiratory tract aspergillosis is a very topical area and this article reports infections caused by the emerging pathogen, Aspergillus felis, as well as four other Aspergillus species that have not previously been reported at this anatomical site in cats.…”