Respiratory case 3

Case Overview

• Patient: Tizzy, a 4-year-old Shetland pony, companion animal

• Chief Complaint: Nasal discharge

History Taking Questions

• Duration of Ownership: How long has the owner had the pony?

• History of Nasal Discharge: Previous episodes? Duration of current discharge?

• Characteristics of Discharge: Unilateral/bilateral, color, smell?

• Frequency: Constant or intermittent?

• Treatment History: Previous treatments administered?

• Management: Stabling conditions, bedding, forage type?

• Associated Symptoms: Coughing, breathing changes, exercise intolerance, change in appetite?

• Other Horses: Are any other horses affected on the property?

Owner Information

• Tizzy owned for 1 year, no prior nasal discharge or illness.

• Current Symptoms: Right-sided thick yellow nasal discharge for 3 months.

• Views other horse unaffected, no cough or exercise intolerance noted.

• Fully vaccinated and wormed.

Clinical Examination Findings

• Heart Rate: 40 beats per minute, normal sinus rhythm

• Nasal Discharge: Purulent, right unilateral

• Respiratory Rate: 12 breaths per minute, normal character

• Auscultation: Normal at rest and on rebreathing

• Lymph Node: Right mandibular lymph node moderately enlarged and non-painful

• Percussion: Right sinus possibly dull

• Temperature: 38.1°C

• Other Observations: No facial swelling or epiphora

Possible Diagnoses

• Most Likely: Upper respiratory tract infectious disease due to unilateral discharge and enlarged lymph node.

• Other Considerations:

  • Chronic sinusitis (primary: bacterial, viral, fungal)

  • Guttural pouch empyema (Strep. equi equi)

  • Viral upper respiratory tract disease (Equine influenza, herpesvirus)

  • Less likely: Asthma, pneumonia, lung tumors.

Differential Diagnosis for Sinusitis

1. Chronic sinusitis (Primary and Secondary)

2. Guttural pouch empyema and mycosis

3. Viral upper respiratory tract diseases

4. Less likely: Asthma, pneumonia, lung tumors

Secondary Sinusitis Causes

• Possible Causes:

• Dental disease

• Sinus cyst

• Sinus neoplasia

Initial Treatment Plan

• Diagnosis: Sinusitis is most likely and can be caused by primary or secondary issues.

• Owner's Preference: No further investigation by the owner.

• Treatment Options:

  • 5-day course of oral trimethoprim sulphonamide and phenylbutazone

Further Diagnostics

• Response to Treatment: Initially effective, but discharge returned post-treatment.

• Next Steps in Investigation:

  • Oral examination with full mouth speculum

  • Head ultrasonography

  • Upper respiratory tract endoscopy

Endoscopic Findings

• Abnormality found at the back of the right nasal meati: discharge from caudal maxillary drainage angle.

Radiographic Findings

• X-Ray Observations: Fluid and/or soft tissue in frontal and maxillary sinuses, absent permanent 3rd cheek teeth (incidental finding).

Final Diagnosis

• Diagnosis: Chronic primary sinusitis due to poor drainage.

• Culture Results: Growth of Streptococcus equi zooepidemicus, sensitive to multiple antibiotics.

• Less likely to have secondary issues based on investigations: dental issues and possible masses ruled out.

Treatment Plan

• Recommended Treatment:

  • 6 weeks of oral trimethoprim sulphonamide

  • 10 days of intramuscular ceftiofur

  • Sinus trephination and lavage

  • Referral for a maxillary sinus flap under standing sedation

Sinus Outcomes

• Procedure: Sinus trephination performed, purulent material released.

• Post-Procedure Care: Lavage performed twice daily with warm salt water for 7 days.

• Outcome: No further episodes of sinusitis noted; Tizzy returned to pasture.