Upper Respiratory Disease: Nasal Passage PDF

Upper respiratory disease: nasal passage Amber Harris, DVM, DACVIM(SAIM) Clinical Assistant Professor VETM5291 – CRH II January 17, 2025 Objectives Describe differentials for unilateral vs bilateral nasal discharge and how they differ. List differentials for serous/serosanguinous, mucopurulen...

Upper respiratory disease: nasal passage Amber Harris, DVM, DACVIM(SAIM) Clinical Assistant Professor VETM5291 – CRH II January 17, 2025 Objectives Describe differentials for unilateral vs bilateral nasal discharge and how they differ. List differentials for serous/serosanguinous, mucopurulent, and hemorrhagic nasal discharge. Discuss diagnostic tests used to work up nasal disease and their pros and cons. Discuss management for lymphoplasmacytic rhinitis (LPR) in dogs and cats; know appropriate expectations to relay to owners. List common infectious diseases of the nasal passages in dogs and cats (e.g. fungal, viral, bacterial, etc.). Discuss treatment recommendations. Discuss diagnosis, treatment, and outcome of nasopharyngeal polyps in cats. Outline Brief physical exam/clinical findings review Nasal discharge Disease processes: Inflammatory/immune mediated Infectious Non-neoplastic masses What is going on in there? Clinical Findings Sneezing Reduced appetite (esp cats) Paroxysmal? Dysphagia Intermittent? Reverse? Pawing/rubbing face Nasal discharge Masses/facial distortion Symmetry? Nasal planum ulceration Character? Seizures Onset? Duration? Progression? Inciting causes or triggers? Review “Nasal Discharge Review” Stertor slides on eLC Physical Examination Checking nasal patency Ocular retropulsion Reverse sneeze Irritation to the nasopharyngeal mucosa NASAL DISCHARGE Nasal Discharge… What could it mean? UNILATERAL BILATERAL Neoplasia Inflammatory rhinitis Tooth root abscess Systemic disease Foreign body Hypertension Fungal Coagulopathy Trauma Infectious Secondary bacterial Viral Highly erosive disease *Neoplasia *Fungal (Asper, Crypto) *Severe trauma  Unilateral disease that is very caudal (far back), could appear bilateral from discharge looping around the back of the nasal septum or refluxing up the contralateral nasal choanae Nasal septum Unilateral discharge could become bilateral if the disease process erodes through the nasal septum. (mass eroding thru septum)  Serous/Serosanguinous Most nasal discharge starts out serous! Often associated with: Viral, allergic, or inflammatory rhinitis Early sign of fluid overload… “Sanguineous” usually indicates: Disease progression Chronic mucosal irritation Mucosal erosion / destruction  Mucopurulent/Mucoid Often indicates secondary bacterial infection Primary nasal bacterial infections = VERY RARE!!! Chronic inflammation (⇧ mucus production) Puppy? …have DISTEMPER on the differential list!!! Sometimes an early indicator of developing pneumonia Courtesy of Dr. L. Guptill Nasal Discharge Progression Most start out as serous Often progresses to serosanguinous Chronic mucosal irritation & inflammation Mucosal erosion May become mucoid to mucopurulent Chronic inflammation +/- secondary bacterial infection (from impaired host defenses!!!) Hemorrhagic (Epistaxis) Erosive diseases Sign of systemic disease! Neoplasia Coagulopathy Inherited vs. acquired Fungal (Aspergillosis) Platelet disorder Trauma Thrombocytopenia Rickettsial disease Immune-mediated Thrombocytopathia Hypertension Vasculitis Hyperviscosity syndrome Disease processes INFLAMMATORY/IMMUNE MEDIATED  Lympho-plasmacytic rhinitis Immune-mediated disease Cause unknown… likely multifactorial Aberrant immune response… dysfunctional PRRs? Chronic exposure to allergens, irritants, infection? Seasonal allergies Previous Feline Herpes virus Hypersensitivity manifestation? Environmental, commensal fungi? Extension of Atopy, IBD?  Lympho-plasmacytic rhinitis Usually middle-aged dogs & cats Dolichocephalic over-represented Dachshunds Clinical signs: Chronic bilateral nasal discharge Commonly serous to mucoid Nasal congestion (stertor) +/- open-mouth breathing +/- sneezing Cats: reduced appetite  Lympho-plasmacytic rhinitis Diagnosis of exclusion Rule out other diseases / triggers Definitive diagnosis: CT → thickened turbinates, fluid Rhinoscopy → mucus, hyperemia Nasal biopsy + histopathology Concern for secondary bacterial infection? Significant mucopurulent nasal discharge LP & neutrophilic inflammation on histopath Culture biopsied piece of nasal tissue (not discharge!)  Lympho-plasmacytic rhinitis Difficult to manage… NOT GOING TO CURE Set client expectations… Goal = improved clinical signs Various treatment protocols: Antihistamines – rarely helpful Eosinophilic inflammation on biopsy? Anti-inflammatories Immunosuppression Immune modulation +/- antibiotics for secondary infections LPR Management strategies Glucocorticoids: Oral prednisone/prednisolone* Anti-inflammatory dose Immunosuppression Dogs = maybe helpful Cats = often works well If + response to oral steroids, consider: Inhaled Topical LPR Management strategies NSAID + antibiotic Immunosuppression Dogs Cyclosporine Doxycycline + Chlorambucil Piroxicam or Radiation therapy meloxicam Immunomodulation Cats Hypoallergenic diet? Azithromycin + Fish oil Meloxicam supplementation? Allergy shots? Dilute Cerenia? Other Management Considerations Treat 2o infections if present Ideally based on tissue culture & sensitivity Environment modification Humidification Trigger avoidance!!! Cigarette smoke Perfumes Cleaners / air fresheners Dusty litter Disease processes INFECTIOUS Fungal Rhinitis – Cryptococcus neoformans Worldwide distribution Found in bird (Pigeon) poop… Cats: Nasal (granuloma) Cutaneous Systemic “Roman nose” Dogs: (rare) CNS Mucopurulent (+/- hemorrhagic) Disseminated nasal discharge Sneezing  Cryptococcus Diagnosis Cytology of nasal discharge Yeast with thick, non-staining capsule Serum latex agglutination (SLA) titer Detects capsular antigen Treatment: +/- surgical debulking Oral anti-fungal therapy Itra- or Fluconazole Treatment ~20 time – 30μmup to 6m capsule; Severe disease or CNS? ~3 – 8μm organism -Monitor SLA titer + amphotericin B (ideally until negative)  Aspergillus fumigatus Sino-nasal disease of dogs Often unilateral mucoid discharge Can be hemorrhagic, epistaxis +/- planum depigmentation German shepherds Rottweiler Cats = Sino-orbital disease Aspergillosis Diagnosis Nasal CT Loss of nasal turbinates Fluid/debris in nose, sinuses +/- bone destruction Orbital bones? Palate? Frontal sinus? Cribriform? Invading CNS? Immune response to Asper is highly destructive & erosive Aspergillosis Diagnosis Rhinoscopy Visualize plaque White, gray, necrotic Can look metallic Cytology +/- fungal culture Normal Sino-Nasal Aspergillosis Treatment Isolated to nasal passages: plaque debulking Topical 1% clotrimazole 1 treatment = 80-85% success 2 treatments = >90% success Infiltrated beyond nose into CNS: Topical clotrimazole cream? Caution with liquid formulations Oral antifungals? Itraconazole + terbinafine Unlikely to successfully clear Feline Upper Respiratory Disease Complex Viral Feline herpesvirus-1 Feline calicivirus First reported in Influenza virus cats in the 1950’s! Covid-19??? Bacterial Mycoplasma species Bordetella bronchiseptica Chlamydia felis Primary Infections Most commonly = VIRAL Feline herpesvirus-1 Represent > 80% Feline calicivirus of cases Co-infections common…  Disease severity! Mycoplasma species Bordetella bronchiseptica Most are Chlamydia felis opportunistic Streptococcus canis Streptococcus equi ss. zooepidemicus Secondary Infections Most commonly = Bacterial Streptococcus sp. Not present in Staphylococcus sp. every case!!! Pasteurella multocida Escherichia coli Often causes: Mucopurulent discharge Systemic signs / illness Patient feels bad Fever, tachypnea, etc. Pathogen Generalities Pathogen shedding Oculo-nasal & oral secretions Transmission Close / direct contact Mutual grooming Overcrowded housing Fomites Bowls, cages, toys, YOU! +/- aerosolization Over 4 feet High morbidity, low mortality General Clinical Signs “Upper Respiratory Tract Infection (URTI)” Oculo-nasal discharge Serous to mucopurulent Squinting Conjunctivitis Sneezing Keratitis Stertor Rhinitis Nasal congestion +/- systemic illness +/- lower airway signs +/- death (kittens)  -Nasal discharge -Stertor -Stertor -Facial deformity -Congested meow Feline Herpesvirus (FHV-1) Feline Viral Rhinotracheitis (FVR) Large, enveloped dsDNA alphaherpesvirus Strain variation minimal Similar to virus of dogs, seals Fragile outside host Easily disinfected!  FHV-1 Most cats are exposed during their lifetime Exposure ≠ infection URTI Dendritic ulcer Ulcerative, eosinophilic dermatitis Feline Calicivirus (FCV) Small, unenveloped ssRNA Survives outside host for prolonged periods ≥ 30 days Resists routine disinfection Following infection: Shed continuously in… ~ 45% for ≤ 30 days ~ 45% for ≥ 75 days >> URTI  URTI Diagnosis History of known exposure Clinical signs & exam Remember unique associations… “Lightning bolt” corneal ulcer? Coughing dog at home? Conjunctivitis only? URTI + multi-systemic illness? +/- organism identification PCR Oronasal +/- conjunctival swabs Viral URTI Management Stress avoidance Supportive care Partial anorexia? Smelly, warm food Clean nose Systemically ill? Fluid, nutritional support Treat secondary infections Relative isolation Remember most cases are viral… Signs are mild & self-limiting There are NO consistently effective primary therapies. Viral URTI Management Antibiotics? VIRAL infections = most common 80-90% of cases!!! Secondary bacterial infections? Oral targeted therapies: Lysine Famciclovir FVRCP vaccine NOT 100% protective Reduces disease severity and duration Disease processes NON-NEOPLASTIC MASSES  Nasopharyngeal Polyps Originate in middle ear or auditory tube Can extend: Up into ear canal (aural) Back into nasopharynx Composed of: Fibrovascular granulation tissue Covered by epithelium Minimal inflammation +/- ulceration Fatty, avascular stalk  Nasopharyngeal Polyps Young cats (most commonly >> heavy sedation Spay hook soft palate, pull rostrally  NP Polyp Treatment Traction avulsion (aka “Grab & Rip”) Clamp the BASE/STALK of the polyp Once clamped, first push INTO the mouth to rip stalk Horner’s Syndrome Loss of sympathetic innervation to eye 1. MIOSIS 2. PTOSIS 3. ENOPHTHALAMUS 4. THIRD EYELID PROTRUSION Induced by polyp removal in ~43% (more likely with surgical removal) Typically resolves 1 – 4 weeks following removal Traction Avulsion Success 41% recurrence rate reported More likely if bullae is Aural >>>> Nasopharyngeal involved Post-removal glucocorticoids Prednisolone 0.5 – 1 mg/kg/day tapered over 6-8 wks Associated with reduced risk of recurrence Recurrence reported from: 19 days… up to 9 months! QUESTIONS??? [email protected] FYI slides  How can you protect your practice from an outbreak? Advanced screening of scheduled appointments Treat URTIs on an out-patient basis if possible Immediately place URTI suspects in room upon arrival Always transport patient in carrier Minimize patient handling & # of staff involved Wear white coat & gloves Change coat / scrubs after seeing URTI patient Disinfect stethoscope, thermometers, etc. Immediate disinfection? Clean room Wash hands Prevention Practices Disinfection Dilute bleach (1:32) 1/2 cup per gallon H20 Potassium peroxymonosulfate (Virkon® Trifectant®) Accelerated hydrogen peroxide (Accel®) Good hygiene Hand washing Sanitizers (60-90% ethanol, propanol) Personal protective equipment Clean equipment  Shelter Medicine? How would your preventative strategies differ? Quarantine incoming!!! Minimize stress? House alone in cages / kennels House in low-stress / traffic area Provide a hiding places Separate cats by >4-5 feet… Impermeable separation between cages? Immediate disinfection? Clean cages, good husbandry Staff PPE & wash / disinfect hands Visitors wash / disinfect hands  Shelter URTI Outbreak Whole other ballgame… Requires its own lecture! Outbreak Prevention & Management Resources UC Davis Koret Shelter Medicine program http://www.sheltermedicine.com/library/resources/pacvet-2015 U of Florida Maddie’s Shelter Program https://sheltermedicine.vetmed.ufl.edu/shelter-services/disease- management/