Respiratory System Diseases

Upper respiratory tract

nasal cavity

sinuses

nasopharynx

larynx

lower respiratory tract

trachea

bronchi

lungs

pleural cavity

components of upper airways

nares

nasal passages and nasal cavity

nasal turbinates

paranasal sinues

nasopharynx

oropharynx

larynx

trachea

protective mechanisms of upper airways

four key defense mechanisms:

• Mucociliary Elevator  

  • Mucus-secreting goblet cells trap particles 

  • Ciliated cells sweep debris toward the pharynx 

• . Turbinate Filtration

  • Creates turbulent airflow to capture larger particles

  • Particles adhere to mucus-covered surfaces 

• Sneeze Reflex

  • Forceful expulsion of air triggered by nasal irritation 

  • Removes irritants from nasal passages 

• Cough Reflex

  • Three-phase process: inspiration, pressurized expiration, glottic opening 

  • Expels irritants from the larynx and trachea 

lower airway components

• Mainstem bronchi (left and right) 

• Lobar bronchi 

• Segmental bronchi 

• Bronchioles 

• Terminal bronchioles 

• Respiratory bronchioles 

• Alveolar ducts 

• Alveolar sacs 

• Alveoli (where gas exchange occurs) 

• Pulmonary capillaries 

• Pleural space and pleura 

alveolar macrophages

• Phagocytic cells that patrol alveolar spaces 

• Engulf and digest foreign particles, bacteria, and debris 

pulmonary lymphatic system

• Drains excess fluid from lung tissue 

• Removes foreign particles and transports them to lymph nodes 

surfactant production

• Reduces surface tension within alveoli 

• Contains immunoglobulins that bind pathogens 

• Enhances macrophage function 

understanding cough

productive cough

• Results from accumulation of material (fluid, cells, debris) in airways 

• Characterized by expectoration of material during coughing 

• Usually associated with conditions that produce excess respiratory secretions 

• Examples: bacterial pneumonia, fungal infections, bronchiectasis 

*Nursing considerations: position patient to facilitate drainage, monitor character and quantity of expectorated material 

nonproductive cough

• No material is expelled during coughing 

• Typically caused by airway irritation without significant secretion accumulation 

• Associated with inflammation, compression, or irritation of airways 

• Examples: collapsing trachea, chronic bronchitis, early pulmonary fibrosis 

*Nursing considerations: note frequency, timing, and triggers of cough 

Diseases of the upper respiratory tract

• epistaxis

• brachiocephalic airway syndrome

epistaxis

nosebleed in dogs and cats

Causes

• localized

  • trauma to nose

  • foreign bodies (grass awns, foxtails)

  • nasal tumors

  • fungal infections

  • bacterial infections

  • severe inflammation of nasal passages

• systemic causes

  • coagulation disorders

    • rodenticide poisoning

    • von willebrand disease

    • hemophilia

    • liver failure

    • disseminated intravascular coagulation (DIC)

• platelet disorders

  • immune-mediated thrombocytopenia

  • tick-borne diseases bone marroe disease

  • drug reactions

  • viral infections (FeLV, FIV)

  • certain cancers (hemangiosarcoma)

• hypertension (high blood pressure)

• hyperviscosity syndrome

Clinical signs - epistaxis

blood from one or both nostrils

range from mild (blood tinged droplets when sneezing) to severe (steady, continuous bleeding)

may see sneezing or nasal discharge before bleeding

with severe bleeding 

signs of blood loss (pale mm, weakness, elevated heart rate)

resp difficulty if blood clots block airways

secondary signs of bleeding in vomit or blood

epistaxis diagnosis

• initial assessment

  • Complete history (including medications, possible toxin exposure, previous episodes) 

  • General physical examination (check for pale gums, other sites of bleeding) 

  • Oral examination to check for dental disease or oral tumors 

• Diagnostics

  • Biochemistry profile /CBC/UA 

  • Coagulation tests (PT, PTT, ACT, buccal bleeding time) 

  • Fungal antigen testing:  

  • Tick-borne disease panels (Ehrlichia, Anaplasma, etc.) 

  • Thoracic radiographs to check for metastasis or fungal disease 

  • Skull/nasal radiographs 

  • Rhinoscopy (visual examination of nasal passages) 

  • Nasal flush and cytology 

  • Biopsy of masses or abnormal tissue 

  • CT scan or MRI for detailed imaging (referral) 

epistaxis treatment

• Keep the animal calm (excitement increases blood pressure and bleeding) 

• Apply ice pack to bridge of nose (constricts blood vessels) 

• Apply pressure when anatomically feasible 

• Oxymetazoline nasal spray (like Afrin) may help constrict vessels 

• Vitamin K therapy for coagulation disorders 

• Other treatments may include following respective to the cause: 

  • Antifungal therapy for fungal infections

  • Tumor management (surgery, radiation, chemotherapy) 

  • Medications to address systemic diseases 

  • Foreign body removal 

epistaxis nursing care considerations

• Minimize stress and handling 

• Monitor vital signs (respiratory rate, heart rate, mucous membrane color) 

• Maintain open airways 

• Maintain a stress-free environment 

• Position patient with head slightly elevated 

• Accurate recording of bleeding episodes (frequency, duration, volume

client education

• Explain that epistaxis is a symptom of an underlying condition, not a disease itself 

• Explain the importance of keeping pet calm during episodes 

• Discuss the importance of identifying the root cause 

brachiocephalic airway syndrome (BAS)

Brachycephalic Airway Syndrome refers to a collection of upper respiratory abnormalities that occur in dogs and cats with shortened skull conformation (brachycephalic breeds). The syndrome results in increased resistance to airflow through the upper respiratory tract, causing chronic respiratory distress.

Brachiocephalic airway syndrome causes

congenital and anatomical:

• Shortened skull (brachycephalic conformation) genetically inherited 

• Predisposition in specific breeds with extreme head shapes 

• Multiple abnormalities typically present simultaneously:  

  • Stenotic nares (narrowed nostril openings) 

  • Elongated soft palate 

  • Everted laryngeal saccules 

  • Hypoplastic trachea (narrowed windpipe) 

  • Laryngeal collapse (in advanced cases

secondary/acquired factors

• Obesity (exacerbates breathing difficulties) 

• High environmental temperatures/Excessive exercise 

• Excitement/stress 

• Progressive worsening over time due to chronic negative pressure in the air 

BAS clinical signs

• Inspiratory stridor (noisy breathing) 

• Stertor (snoring sounds) 

• Exercise intolerance 

• Increased respiratory effort (exaggerated chest and abdominal movements) 

• Open-mouth breathing/panting at rest 

• Cyanosis (blue discoloration of mucous membranes) during exertion 

• Syncope/Collapse in severe case 

BAS diagnosis

• Physical exam, history, oral and ocular exam

• Auscultation of stridor and respiratory sounds 

• Weight assessment 

• Thoracic radiographs to evaluate tracheal diameter, heart size, and check for aspiration pneumonia 

• Advanced imaging (CT scan) in complex cases 

BAS treatment

• Maintaining calm environment to reduce respiratory distress 

• Weight loss if obese 

• Avoid excessive exercise or stress, especially in hot weather 

• Supplemental oxygen therapy for acute distress 

• Anti-inflammatory medications to reduce airway swelling 

• Surgical interventions (often multiple procedures performed simultaneously):  

  • Stenotic nares correction (alar wedge resection) 

  • Soft palate resection (staphylectomy) 

  • Everted laryngeal saccule excision 

  • Permanent tracheostomy (severe cases with laryngeal collapse) 

BAS client education

• Explanation of the anatomical abnormalities involved 

• Progressive nature of the disease 

• Lifelong management requirements 

• Weight management (crucial for symptom control) 

• Exercise modification:  

  • Recognition of respiratory distress signs 

  • Temperature control (avoid heat) 

  • Avoiding stressful situations 

BAS nursing notes

Effective oxygenation is critical for brachycephalic patients due to their anatomical respiratory compromise and limited reserve capacity. During respiratory distress or perioperative care, minimize stress and handling while providing oxygen via non-restrictive methods such as oxygen cages or flow-by techniques. Early intervention with appropriate oxygen therapy and patient positioning is essential for preventing life-threatening complications in these high-risk patients. 

infectious canine tracheobronchitis (ICT)

"kennel cough," is an acute, highly contagious respiratory disease characterized by inflammation of the upper airways, specifically the trachea and mainstem bronchi.

It represents a complex of infections rather than a single disease entity, with multiple pathogens often involved simultaneously. 

Causes

• Bordetella bronchiseptica (bacteria) - most common causative agent 

• Canine parainfluenza virus 

• Canine adenovirus type 2 

• Canine herpesvirus 

• Mycoplasma species (often opportunistic) 

• Canine distemper virus (less common in vaccinated populations) 

Transmission

• Highly contagious via aerosol route (coughing, sneezing) 

• Direct dog-to-dog contact 

Clinical signs

• Dry, harsh, hacking characteristic cough (occurring in fits)easily elicited by tracheal palpation 

• Nasal/ocular discharge  

• +/- Fever 

• +/- Lethargy 

Dx

• History of exposure to other dogs 

• Physical examination (tracheal sensitivity)

• Further Diagnostics can include: 

  • Thoracic radiographs to rule out pneumonia or lower airway disease 

  • Complete blood count to assess for systemic inflammation 

  • Transtracheal wash (TTW) or bronchoalveolar lavage (BAL) for culture 

  • Culture and sensitivity testing for B. bronchiseptica 

Tx

• Antitussives 

• Antibiotics 

• Supportive care such as: Humidification of airways, rest, and corticosteroids 

Client education

• Self-limiting nature of the disease (2-3 weeks for resolution)

• Highly contagious to other dogs 

• Need for isolation from other dogs until resolution 

• Intranasal or injectable vaccine as prevention 

Collapsing trachea

Collapsing Trachea is a progressive respiratory condition characterized by weakening and subsequent collapse of the tracheal rings during respiration. While the exact cause remains unclear, it is primarily a disorder of small breed dogs and can significantly impact quality of life without proper management 

Causes

• Reduced glycoprotein and glycosaminoglycan content in tracheal cartilage 

• Genetic predisposition in toy and miniature breeds 

• Progressive degeneration of tracheal cartilage with age 

Clinical signs

• Characteristic harsh, dry "goose honk" cough 

• Cough exacerbated by excitement, exercise, pulling on collar 

• Respiratory distress with severe collapse 

• Exercise intolerance 

• Cyanosis in severe cases 

• Increased respiratory effort 

Diagnosis

• Physical exam with Tracheal palpation elicits characteristic "goose honk" cough 

• Radiography: DV and lateral views during both inspiration and expiration 

• Fluoroscopy: Dynamic visualization of tracheal collapse during respiration

• Ultrasonography: Real-time assessment of tracheal movement 

• Bronchoscopy: Direct visualization of collapsing trachea during respiration 

Treatment

• Cough suppressants, anti-inflammatories, and bronchodilators as needed 

• Weight reduction 

• Surgical options (for severe cases):  

  • Extraluminal prosthetic rings /Intraluminal stents for  

Client educaiton

• Weight management 

• Reduce environmental and stress triggers 

• Use harness for walking 

• Recognize respiratory distress signs

Pneumonia

Pneumonia is an inflammation of the pulmonary parenchyma (small airways, interstitial tissues, and alveoli) that results in respiratory disturbance, and is a potentially life-threatening condition

Causes

• Bacterial infection (often secondary to other conditions) 

• Viral infection (canine distemper, adenovirus, parainfluenza, feline calicivirus) 

• Fungal infection  

• Parasitic invasion  

• Protozoal infection  

• Aspiration of: Vomitus or regurgitated food or Improperly administered medication 

Clinical signs

• Cough (may be dry/nonproductive or wet/productive) 

• Lethargy and anorexia 

• Fever 

• Respiratory distress 

• Possible hypoxia in severe cases 

• Increased respiratory rate and effort 

• Nasal discharge (in some cases) 

• Signs may vary depending on the causative agent 

• Some cases may present with minimal clinical signs despite significant radiographic changes 

Diagnosis

• History and clinical findings 

• Thoracic radiographs  

• Fluid analysis from airway samples  

• Complete blood count (leukocytosis common) 

Treatment

• Treatment approaches vary based on patient status (stable, unstable, or critical) 

  • Antimicrobial therapy  

  • Supportive care - Hydration management/IV fluids  

  • Respiratory support  

  • Airway clearance techniques (nebulization/vaporization, coupage, light exercise) 

  • Regular monitoring (rechecks and radiographs typically weekly) 

Client education

• Recognizing signs of improvement or deterioration 

• Compliance with ongoing rechecks  

  • Medication administration techniques 

pneumonia nursing note

: Comprehensive nursing care for pneumonia patients is critical for recovery, incorporating oxygen support, fluid therapy, antimicrobial administration, and various physiotherapy techniques (nebulization, coupage) that collectively mobilize respiratory secretions, prevent dehydration, and optimize pulmonary function while maintaining vigilant monitoring for clinical improvement or deterioration 

pleural effusion

Pleural effusion is the buildup of fluid within the pleural space. 

• Breed predispositions: Afghans and oriental breeds of cats for chylothorax 

• Age factors: Older cats more likely to develop chylothorax than younger cats 

Causes

everal underlying causes include:  

• Congestive heart failure (especially right-sided failure) 

• Intrathoracic neoplasia (lymphoma, mesotheliomas, metastatic carcinomas) 

• Empyema (purulent exudative pleural effusion) 

• Chylothorax (accumulation of chylous fluid in the pleural space) 

Clinical Signs

• Dyspnea (labored breathing) 

• Respiratory distress 

• Possible cough 

• Possible fever 

• Pleural pain 

• Circulatory compromise 

Diagnosis

• Retraction of lung borders from thoracic wall 

• Blunting of costophrenic angles 

• Partial to total obliteration of cardiac borders 

• Widened mediastinum 

Thoracocentesis

• Cytology 

• Specific gravity 

• pH 

• Protein concentration 

• Packed cell volume 

• Total and differential white blood cell count 

Treatment

Based on underlying cause:  

• Congestive heart failure: Treat underlying disease, therapeutic thoracocentesis as needed 

• Neoplasia: Therapeutic thoracocentesis, chemotherapy, pleurodesis 

• Pyothorax:  

  • Tube thoracostomy with continual drainage (bilateral if necessary) 

  • Antibiotic therapy based on culture and sensitivity 

  • Long-term treatment (at least 3 months) 

Client education

• Effusion will return unless primary disease is treated 

• Treatment can be long-term and expensive 

• Periodic reevaluation is required 

Nursing Note: Care should be taken when restraining any animal with pleural effusion. Further distress can lead to an emergency situation where the patient can expire.

feline asthma

Feline asthma is a common respiratory condition in cats where the airways become inflamed and narrow in response to certain triggers in the environment.

It works much like human asthma - when a cat breathes in something it's allergic to, the body overreacts, causing the breathing tubes to tighten, swell, and fill with mucus. This makes it difficult for the cat to breathe, leading to coughing, wheezing, and sometimes severe breathing difficulty. The condition typically comes and goes in episodes, with normal breathing in between. 

causes

• Type I hypersensitivity reaction to inhaled allergens 

• Mediated by immunoglobulin E (IgE) and immune cells (mast cells, basophils, eosinophils) 

• Common in young to middle-aged cats 

• Equal representation in males and females 

• Suspected genetic component 

• Environmental triggers (dust, aerosols, smoke, perfume, cat litter dust) 

clinical signs

• Tachypnea (especially at rest) 

• Dyspnea (often episodic) 

• Wheezing (may be audible without stethoscope in severe cases) 

• Cough (uncommon) 

• Episodic respiratory distress with normal behavior between episodes 

• Bronchoconstriction (smooth muscle contraction around bronchioles) 

• Increased mucus secretion 

diagnosis

• History and physical examination 

• Normal minimum database (CBC, serum biochemistry, urinalysis) 

• Thoracic radiographs  

• Airway secretion analysis  

• R/O Parasitic, bacterial, and neoplastic possibilities

Treatment

Acute crisis treatment:  

• Bronchodilators (terbutaline) 

• Short-acting corticosteroids 

• Supplemental oxygen 

• Nebulilization  

• Oral corticosteroids (prednisone) 

• Injectable corticosteroids if oral administration not feasible 

• Bronchodilators (terbutaline, albuterol) 

client education

• Typically, a lifelong condition 

• Environmental /stress management 

• Most cats can live normal lives with proper management 

• Periodic episodes of respiratory distress will occur 

• Make sure clients are taught how to use MDI (Metered Dose Inhalers)     for long term management if at home treatment is required  

Feline Herpesvirus (Rhinotracheitis)

FHV

highly contagious upper respiratory disease in cats with high morbitidy rates that can be extremely severe in young kittens

causes:

• Caused by feline herpesvirus type 1 (FHV-1) 

• Occurs year-round in both vaccinated and unvaccinated populations 

• Transmission occurs via aerosolization (sneezing) and direct cat-to-cat contact 

• Queens may transmit the disease to kittens during grooming 

• Virus typically survives only 18-24 hours in the environment 

• Cats shed the virus for approximately 3 weeks post-infection 

• Fomites include food dishes, clothing, bedding, and toys 

clinical signs

• Acute onset of sneezing 

• Severe conjunctivitis 

• Purulent rhinitis (nasal discharge) 

• Fever 

• Depression 

• Anorexia (loss of appetite) 

• Ulcerated nasal planum 

• Excessive salivation 

• Potential abortion in pregnant queens 

• Corneal ulcers 

treatment

• Fluid therapy (IV, SQ) to address dehydration 

• Broad-spectrum antibiotics to prevent secondary infections 

• Decongestants, vaporization, or antihistamines as appropriate 

• Specialized feeding approaches including force-feeding or offering strong-smelling foods/Warming food to enhance palatability 

• Minimizing stress on affected animals 

• Topical antiviral medications for ocular infections 

• Avoiding cortisone as an anti-inflammatory agent 

Client education

• Educate about how FVR is highly contagious among cats 

• Be aware that humans can transmit the disease between cats via hands and clothing

• Standard disinfectants effectively kill the virus 

• The disease affects only cats, not humans or other animals 

• Importance of completing full course of medications 

• Significance of isolation during active infection 

• Maintaining vaccination schedules 

Feline Calcivirus

Feline Calicivirus (FCV) is an acute, highly contagious upper respiratory tract disease in cats. It is one of the principal diseases in the feline respiratory disease complex with most severe cases occurring in kittens

Causes

• Multiple strains of calicivirus exist, each potentially causing different clinical manifestations 

• Transmission occurs through direct contact with infected cats 

• Can be spread through small airborne droplets (such as from sneezing) and contaminated objects 

Clinical signs

• Fever, which may reach high temperatures 

• Serous ocular and/or nasal discharge 

• Mild conjunctivitis 

• Oral ulcers with increased salivation 

• Pneumonia in some cases 

• Acute arthritis in kittens ("limping kitten syndrome") 

• Diarrhea may occur 

• Depression and loss of appetite 

• Some strains affect the lining of the mouth and lungs 

• Some strains produce fluid buildup in the lungs (pulmonary edema) 

• Mouth sores/ulcerative stomatitis (distinguishing feature from FVR) 

• Joint pain and lameness (particularly in 8–12 week old kittens) 

Treatment

• Supportive care is the mainstay of treatment 

• Broad-spectrum antibiotics to prevent secondary bacterial infections 

• Force-feeding if ulcers prevent cat from eating normally 

• Oxygen therapy if dyspnea (difficulty breathing) is present 

• Fluid therapy for dehydrated patients 

• Environmental disinfection using bleach (effective against the virus) 

• Antihistamines may be prescribed early in the disease course 

• Nutritional support for cats unwilling to eat 

Client education

• Stress management is important to prevent relapses 

• Proper isolation of infected cats is necessary to prevent spread to other cats 

• Environmental disinfection is critical due to the virus's ability to survive in the environment & highly contagious nature  

• Continued forced feeding may be necessary for cats unwilling to eat due to oral pain 

• Vaccination is effective in preventing the disease but may not protect against all strains 

Fungal Respiratory diseases

Blastomycosis

Coccidioidomycosis

Histoplasmosis

Cryptococcosis

Blastomycosis

Blastomycosis is a systemic fungal infection. The organism exists in a mycelial phase in soil and laboratory cultures but converts to a yeast form in infected tissues. This disease predominantly affects dogs, with lower incidence in cats, and is endemic in the eastern United States. 

Causes

• Caused by the dimorphic fungus Blastomyces dermatitidis 

• Primary habitat is soil, especially in the Mississippi, Ohio, and St. Lawrence River valleys and Great Lakes regions 

• Highest incidence in Kentucky, Illinois, Tennessee, Mississippi, Indiana, Iowa, Ohio, Arkansas, and North Carolina 

• Three clinical forms: primary pulmonary infection, disseminated disease, and local cutaneous infections 

• Primary route of infection is inhalation of fungal spores 

• Wound contamination is a secondary route of infection 

• Incubation period is 5 to 12 weeks 

Clinical signs

• Anorexia 

• Depression 

• Weight loss 

• Fever (>103°F) 

• Cough and dyspnea (difficulty breathing) 

• Ocular and nasal discharge 

• Wound exudates (serosanguinous to purulent) 

• Lymphadenopathy (enlarged lymph nodes) 

• CNS signs in cases with neurological involvement 

Diagnosis

• CBC and blood chemistry show nonspecific signs of chronic disease 

• Hypercalcemia may be present in some dogs 

• Cytology to identify organism in tissues or secretions 

• Radiography reveals generalized diffuse, nodular interstitial pattern 

• Osseous lesions in epiphyseal areas of long bones may be present 

• Serology testing for confirmation 

• Lack of response to antibiotic and corticosteroid therapy should raise suspicion 

Treatment

• Antifungals, Injectable or Oral (Amphotericin-B most effective, but does have some side effects that include cardiac and renal issues) 

• Oral antifungals can be long term 

Client education

• Caution needed when handling animals with draining lesions 

• Humans share the same environment as pets and may be exposed to the same fungal spores 

• Prognosis depends on disease stage and animal's sex (females have higher survival rates) 

• Relapses are common, requiring long-term management 

• Treatment medications are expensive 

Coccidiodomycosis

Coccidioidomycosis is a fungal infection that can affect both dogs and cats, with young male dogs being most susceptible. Clinical signs may take weeks to years to appear after exposure to the fungal spores. Sometimes referred to as “Valley Fever” in dogs. 

Causes

• Caused by Coccidioides immitis, a dimorphic soil fungus 

• Found primarily in semiarid areas with sandy soils and mild winters 

• Endemic in California, Nevada, Utah, Arizona, New Mexico, and Texas 

• Inhalation of fungal spores is the primary route of infection 

• Clinical signs may not appear for weeks to years after exposure 

clinical signs

• Mild, nonproductive cough 

• Low-grade fever 

• Anorexia 

• Weight loss 

• Weakness and depression if systemic 

• Lameness, soft-tissue swelling, and pain if bone involvement 

• Lymphadenopathy (may or may not be present) 

• Myocarditis (may or may not be present) 

• Skin lesions 

• Signs of CNS involvement in severe cases 

Diagnosis

• CBC or blood chemistry shows nonspecific signs of chronic disease 

• Cytology/biopsy may reveal thick, double-walled spherical bodies 

• Radiography shows a wide range of parenchymal changes in the lung 

• Serology testing is available 

• Titers greater than 1:16 to 1:32 indicate active disease 

Treatment and prevention

• Treatment options:  

  • Anti-Fungals such as Ketoconazole/IItraconazole:   

  • Oral medications may be required for 6-12 months 

Client education

• No known risk for animal-to-human transmission exists 

• Use caution when treating animals with draining lesions 

• Response to treatment is usually good, but relapses are common 

• Lifelong treatment may be necessary to maintain remission 

• Medications are expensive 

• Avoid endemic areas with high environmental loads 

• No effective vaccine available 

Histoplasmosis

Histoplasmosis is a fungal disease that is endemic in much of the central and eastern United States. The fungus is commonly associated with bird and bat droppings. Clinical histoplasmosis affects cats and dogs with equal frequency 

Causes

• Caused by Histoplasma capsulatum, a dimorphic soil fungus 

• Endemic in 31 of the 48 continental states, most common in Ohio, Missouri, and the Mississippi River Valley 

• Associated with bird and bat droppings 

• Inhalation is the primary route of infection 

• Gastrointestinal tract may also be susceptible 

• Incubation period is 12-16 days 

• Equally common in cats and dogs 

Clinical signs

• Feline (primarily pulmonary signs):  

  • Weight loss 

  • Fever 

  • Anorexia 

  • Pale mucous membranes 

  • May or may not show dyspnea 

  • Hepatomegaly 

  • Peripheral lymphadenopathy 

  • May or may not show ocular lesions 

• Canine (primarily gastrointestinal signs):  

  • Weight loss 

  • Diarrhea (large bowel) 

  • Dyspnea 

  • Cough 

  • Pale mucous membranes 

  • Low-grade fever 

Diagnosis

• CBC/Blood chemistry (results usually normal) 

• Cytology or histopathology: Small, round intracellular bodies surrounded by a light halo 

• Radiology: Diffuse or linear pulmonary interstitial patterns (thorax) 

• GI tract radiography may indicate ascites 

• Serology available but results often false negative 

Treatment and prevention

• treatment options

  • antifungals PO

  • ketoconazole, itraconazole

Client education

• CBC/Blood chemistry (results usually normal) 

• Cytology or histopathology: Small, round intracellular bodies surrounded by a light halo 

• Radiology: Diffuse or linear pulmonary interstitial patterns (thorax) 

• GI tract radiography may indicate ascites 

• Serology available but results often false negative 

Cryptococcosis

causes

• Caused by Cryptococcus neoformans 

• Commonly found in avian excreta, especially pigeon droppings 

• Inhalation is the primary route of infection 

• Immunosuppressed animals are more likely to become infected 

• Most common systemic mycosis in cats, less common in dogs 

clinical signs

• Canine:  

  • Primarily CNS lesions (vestibular dysfunction) 

  • Skin lesions in about 25% of cases 

• Feline:  

  • Nasal cavity and sinus lesions 

  • Chronic nasal discharge 

  • Nasal granulomas 

  • Lymphadenopathy 

  • CNS involvement (seen in 25% of cases) 

  • Eye lesions (may or may not be present) 

  • Low-grade fever, malaise 

  • Weight loss, anorexia 

Diagnosis

cytology of aspirates, impression smears, cerebrospinal fluid

commercial antigen test available

TX

• Antifungals. Minimum treatment time is 2 months

Client ed

• Prognosis is fair to good unless there is CNS involvement, which worsens the outlook 

• No known health hazard to humans exists, Avoid areas with high concentrations of pigeon droppings 

• Treatment may be prolonged and requires consistency 

• Regular monitoring is essential to assess response to therapy 

• No effective vaccine available 

fungal key differentiating factors

• Blastomycosis: High fever, most common in dogs, females have better prognosis 

• •

  Coccidioidomycosis: Young male dogs most affected, bone involvement common, long latency period 

• •

  Histoplasmosis: Different presentation in cats (pulmonary) vs. dogs (GI), associated with bird/bat droppings 

• •

  Cryptococcosis: Most common fungal infection in cats, primarily nasal/CNS signs, good prognosis unless CNS involved

Nursing note

Core Vaccines are as follows for Dogs & Cats by Current AVMA recommendations and help to reduce the risk of many infections discussed in this course.   

Feline core vaccines  

• rabies 

• calicivirus (often given as part of combo vaccine FVRCP) 

• panleukopenia (often given as part of combo vaccine FVRCP) 

• FELV (based on lifestyle- would be recommended for indoor/outdoor cats)  

Canine core vaccines  

• rabies  

• distemper (often given as part of combo vaccine DHPP) 

• parvovirus (often given as part of combo vaccine DHPP) 

• adenovirus (often given as part of combo vaccine DHPP) 

• Lepto (recommended) and is generally given as part of DHPP, unless client and veterinarian decide otherwise