Introduction

• Cause:
  • Nutritional such as hypovitaminosis A.
  • Inappropriate husbandry leading to immunosuppression.
  • Bacterial infections, eg Klebsiella spp, Salmonella spp, Pseudomonas spp, Proteus spp, Pasteurella spp, Aeromonas spp, Morganella morganii, Mycoplasma spp, Chlamydia pneumoniae, Mycobacteria spp.
  • Fungal infections, eg Aspergillus spp.
  • Neoplastic disease affecting the sinus tract.
  • Traumatic injuries to the face, eg when live prey is fed.
  • Viral infections such as Ferlavirus, Sunshinevirus, Arenavirus (inclusion body disease; IBD), Reovirus, Nidovirus in snakes as well as Herpes viruses in Chelonia.
  • Dysecdysis leading to obstruction of nostrils and dyspnea.
  • Parasitic such as disseminated intranuclear coccidiosis.
• Signs: nasal discharge, bubbling at the nose, open mouth breathing, dyspnea, lethargy, inappetence, weakness, sudden death.
• Diagnosis: thorough husbandry review including nutrition, culture and sensitivity swabbing, PCR testing, diagnostic imaging, bronchial/bronchoalveolar lavage, cytology, blood cultures.
• Treatment: based on causative agents, systemic antibiotics, anti-inflammatories, nebulizing therapy.
• Prognosis: good to guarded depending on the time of presentation.

Pathogenesis

Etiology

• Husbandry Chelonia husbandry Lizard husbandry Snake husbandry:
  • Nutritional such as hypovitaminosis A Hypovitaminosis A most commonly seen in aquatic and semi-aquatic species.
  • Inappropriate husbandry leading to immunosuppression with lack of appropriate temperatures and UVB exposure, eg outdated lamps, wrong % UVB for the species kept.
• Infectious causes:
  • Bacterial infections: Klebsiella spp, Salmonella spp, Pseudomonas spp, Proteus spp, Aeromonas spp, Morganella morganii, Mycoplasma spp, Chlamydia pneumoniae, Mycobacteria spp Lower respiratory tract disease.
  • Fungal infections, eg Aspergillus spp Fungal infections overview.
  • Viral infections such as Ferlavirus Ferlavirus infection, Sunshinevirus Sunshinevirus infection, Arenavirus (IBD, inclusion body disease) Inclusion body disease, Reovirus, Nidovirus in snakes Lower respiratory tract disease as well as Herpes viruses Herpes virus infection in Chelonia.
• Neoplastic disease affecting the sinus tract.
• Traumatic injuries Traumatic injuries to the face, eg when live prey is fed or striking at glass enclosures.

Predisposing factors

General

• Inappropriate husbandry Chelonia husbandry Lizard husbandry Snake husbandry with insufficient temperatures, lack or inappropriate UVB, nutritional deficiencies Nutritional requirements.
• Sub-optimal husbandry, including high stocking densities, poor ventilation, poor hygiene, use of organic substrate/bedding
• Underlying disease such as hepatic lipidosis Hepatic lipidosis.

Specific

• Hypovitaminosis A Hypovitaminosis A may lead to non-specific signs such as inappetence, lethargy, periorbital swelling and nasal discharge.

Pathophysiology

• Dysecdysis Ecdysis / dysecdysis may lead to obstruction of nostrils and dyspnea Dyspnea.
• Hypovitaminosis A Hypovitaminosis A may lead to immunocompromise, periorbital swelling and predispose to secondary bacterial infections. Deficiencies of this vitamin affect the glandular mucous membrane epithelium.
• Chronic stress of life in captivity may predispose reptiles to secondary infections with mycobacteria and fungal agents; this is often linked to poor husbandry and dirty conditions.

Timecourse

• Days to months.
• Herpes virus and Mycoplasma infections may resurface even after initial improvement. Recurrent cases of disease should be investigated for underlying immunosuppression.

Epidemiology

• Captively kept reptiles are at a higher risk of repeated rostral trauma from collisions with the door of enclosure Traumatic injuries.
• Feeding of live prey risks head trauma and injury in snakes: this is illegal in the UK unless indicated on welfare grounds (where an animal will not feed from dead prey under any circumstances). Such injuries may be more common in wild reptiles.

Diagnosis

Treatment

Prevention

Outcomes