Canine and Feline Nasal Disease: Case Study Overview

Case 1: Crystal

• Profile: 3-year-old Domestic Medium Hair (DMH) cat

• Background: Found as a stray; Positive for Feline Leukemia Virus (FeLV)

• Clinical Signs:

  • Unilateral mucopurulent nasal discharge, occasionally hemorrhagic

  • Facial deformity and exophthalmos

  • Proliferative retinal lesions diagnosed via fundoscopic exam

Diagnostic Assessment

• Feline Fundoscopic Exam: Shows abnormal findings consistent with the disease.

Case Study Clinical Pathogen Investigation

• Polypoid Nasal Mass: Indicative of possible fungal involvement.

Potential Pathogens and Sources

Organism Identification

• iClicker Question: What is the organism likely identified?

  • A. Coccidioides immitis

  • B. Aspergillus fumigatus

  • C. Cryptosporidium parvum

  • D. Cryptococcus neoformans

Exposure Sources

• iClicker Question: Where did Crystal get exposed?

  • All options are likely (ubiquitous exposure from soil, environment, and pigeon droppings).

Infection Factors

• iClicker Question: Why did Crystal get infected?

  • B. Immunosuppression from retroviral infection

  • Increased risk factors: proximity to other cats and pigeons.

Clinical Impact of Cryptococcus Neoformans

• Opportunistic Infection:

  • Source: Ubiquitous organism found in pigeon droppings.

  • Commonly affects cats over dogs; leading cause of fungal rhinitis in felines.

Pathophysiology

• Characteristics:

  • Saprophytic budding yeast with a polysaccharide capsule

  • Strategy to evade phagocytosis and contributes to immune dysfunction

Clinical Presentation

• Symptoms:

  • Sneezing, nasal discharge, airflow obstruction

  • Distortion of the nasal bridge, ulcers (40-50%) of nasal planum

  • Potential retinal granulomas (20%) and CNS involvement (20%).

Treatment Approaches

• Nasal Cryptococcosis:

  • Primary treatments:

    • A. Topical antifungal therapy

    • B. Surgical removal of nasal granulomas

  • Systemic antifungal therapy as adjunctive treatment.

Case 2: Dutch

• Profile: 6-year-old Male German Shepherd Dog (GSD)

• Background: Working drug sniffer at Port Huron Border Patrol

• Clinical Signs:

  • 3-month history of progressive left unilateral nasal discharge, episodic epistaxis

  • Mild laryngeal cough and nasal planum depigmentation.

Diagnostic Imaging

• CT Findings:

  • Left-sided turbinate loss, thickening, and opacity in the left frontal sinus.

Rhinoscopy Findings

• Observations:

  • White colonies along the nasal mucosa and in the frontal sinus.

  • Plaques observed.

Cytology Results

• Nasal Cytology:

  • Neutrophilic inflammation with numerous septate branching hyphae indicating a fungal infection.

Possible Pathogen Identification

• iClicker Question: What is this organism?

  • A. Dictyocaulus arnfeldi

  • B. Coccidioides immitis

  • C. Cryptococcus neoformans

  • D. Aspergillus fumigatus

Infection Origin

• iClicker Question: How did Dutch get this infection?

  • Likely from the environment or other infected dogs.

Aspergillus Fumigatus Overview

• Profile:

  • Septate and branching hyphae associated with fungal infections.

  • Common in young to middle-aged dolichocephalic breeds, particularly GSDs.

  • IgA deficiency noted in some affected dogs.

Clinical Presentation of Aspergillosis

• Symptoms:

  • Mucopurulent nasal discharge (unilateral or bilateral)

  • Epistaxis, sneezing, nasal pain, pawing/rubbing behavior

  • Facial deformity and nasal planum depigmentation.

Treatment for Nasal Aspergillosis

• Therapeutic Options:

  • A. Topical antifungal therapy (Clotrimazole, Enilconazole)

  • B. Surgical debridement of frontal sinus granulomas

  • Systemic antifungal therapy as needed.

Surgical Interventions

• Specific Procedures:

  • Frontal sinusotomy for severe sinus involvement

  • Endoscopic investigations.

  • Address local immune deficiencies in predisposed breeds.