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Created page with "{{Template:Manson}} [[Image:|centre|500px]] <br /> '''A 13-year old neutered male DSH cat presents with inspiratory dyspnoea, frequent sneezing, congestion, weight loss and p..."
{{Template:Manson}}
[[Image:|centre|500px]]
<br />
'''A 13-year old neutered male DSH cat presents with inspiratory dyspnoea, frequent sneezing, congestion, weight loss and partial anorexia of three months’ duration. Physical examination reveals bilateral mucopurulent nasal discharge. Amoxicillin/clavulanic acid has been administered unsuccessfully. Vaccinations are up-to-date and the cat is free roaming. A smear is prepared from a nasal flush (Wright’s, ×40). Cranial radiographs do not reveal any osteolytic lesions or evidence of a mass.'''
<br />
<FlashCard questions="3">
|q1=What is your diagnosis based on cytological observation?
|a1=
The microphotograph illustrates a hyphal structure compatible with Aspergillus species. Nasal aspergillosis is therefore the likely diagnosis.<br><br>
This infection is more common in dogs than in cats, particularly long-nosed breeds (e.g. Collies).
|l1=
|q2=What other diagnostic tests can be performed to support this diagnosis?
|a2=
#Rhinoscopy can reveal atrophy of turbinates and the presence of white or grey plaques.
#Histological examination, like cytology, can demonstrate fungal hyphae; these are nonpigmented, segmented and branching structures; fungal culture can be performed on material obtained from a nasal flush or tissue sampling during rhinoscopy.
#Serology for detection of antibodies against Aspergillus species is a complementary diagnostic tool but less useful, as false positives do occur. A positive test supports prior exposure to the organism but does not confirm current infection. A negative antibody test does not rule out the possibility of Aspergillus infection.
#Radiographic examination may reveal nonspecific osteolytic lesions that may also be observed with neoplasia.
<br><br>
It should be noted that for cytological examination, material obtained via a nasal flush or biopsy is preferred to nasal secretions, which may not contain the organism.
|l2=
|q3=What treatment can be recommended?
|a3=Oral fluconazole or itraconazole can be administered; topical infusion of an antifungal drug such as clotrimazole has been shown to be effective in dogs, and may clear infections more successfully than systemic therapy. <br><br>
Note: Aspergillus organisms in cytological preparations are usually observed as uniform, septate hyphae of 3–6 microns in width with 45-degree angle (dichotomous) branching. <br><br>
A differential diagnosis is phycomycosis, but these fungi are rarely septate. The presence of septate, branching hyphae in a nasal cytological preparation is strongly supportive of aspergillosis. <br><br>
Definitive diagnosis is by evaluation of reproductive structures, which are seldom seen in cytological specimens but can be identified in preparations of fungal cultures.<br><br>
Nasal flushings can be very frustrating because they may reflect nonspecific inflammation and may not contain diagnostic features. Client education regarding the possibility of a nonrepresentative specimen and the possible need to progress to nasal biopsy is recommended. <br><br>
Nasal biopsy specimens taken from multiple locations may be needed and aggressive sampling is recommended to obtain specimens that will give the clinician and pathologist confidence in making a diagnosis.
|l3=
</FlashCard>
[[Category:Cytology Q&A]]
[[Image:|centre|500px]]
<br />
'''A 13-year old neutered male DSH cat presents with inspiratory dyspnoea, frequent sneezing, congestion, weight loss and partial anorexia of three months’ duration. Physical examination reveals bilateral mucopurulent nasal discharge. Amoxicillin/clavulanic acid has been administered unsuccessfully. Vaccinations are up-to-date and the cat is free roaming. A smear is prepared from a nasal flush (Wright’s, ×40). Cranial radiographs do not reveal any osteolytic lesions or evidence of a mass.'''
<br />
<FlashCard questions="3">
|q1=What is your diagnosis based on cytological observation?
|a1=
The microphotograph illustrates a hyphal structure compatible with Aspergillus species. Nasal aspergillosis is therefore the likely diagnosis.<br><br>
This infection is more common in dogs than in cats, particularly long-nosed breeds (e.g. Collies).
|l1=
|q2=What other diagnostic tests can be performed to support this diagnosis?
|a2=
#Rhinoscopy can reveal atrophy of turbinates and the presence of white or grey plaques.
#Histological examination, like cytology, can demonstrate fungal hyphae; these are nonpigmented, segmented and branching structures; fungal culture can be performed on material obtained from a nasal flush or tissue sampling during rhinoscopy.
#Serology for detection of antibodies against Aspergillus species is a complementary diagnostic tool but less useful, as false positives do occur. A positive test supports prior exposure to the organism but does not confirm current infection. A negative antibody test does not rule out the possibility of Aspergillus infection.
#Radiographic examination may reveal nonspecific osteolytic lesions that may also be observed with neoplasia.
<br><br>
It should be noted that for cytological examination, material obtained via a nasal flush or biopsy is preferred to nasal secretions, which may not contain the organism.
|l2=
|q3=What treatment can be recommended?
|a3=Oral fluconazole or itraconazole can be administered; topical infusion of an antifungal drug such as clotrimazole has been shown to be effective in dogs, and may clear infections more successfully than systemic therapy. <br><br>
Note: Aspergillus organisms in cytological preparations are usually observed as uniform, septate hyphae of 3–6 microns in width with 45-degree angle (dichotomous) branching. <br><br>
A differential diagnosis is phycomycosis, but these fungi are rarely septate. The presence of septate, branching hyphae in a nasal cytological preparation is strongly supportive of aspergillosis. <br><br>
Definitive diagnosis is by evaluation of reproductive structures, which are seldom seen in cytological specimens but can be identified in preparations of fungal cultures.<br><br>
Nasal flushings can be very frustrating because they may reflect nonspecific inflammation and may not contain diagnostic features. Client education regarding the possibility of a nonrepresentative specimen and the possible need to progress to nasal biopsy is recommended. <br><br>
Nasal biopsy specimens taken from multiple locations may be needed and aggressive sampling is recommended to obtain specimens that will give the clinician and pathologist confidence in making a diagnosis.
|l3=
</FlashCard>
[[Category:Cytology Q&A]]