Epistaxis and Hemoptysis

W. David Wilson • Jeanne Lofstedt • Jeffrey Lakritz

■ Definition Epistaxis is defined as the presence of blood at the external nares⁴⁷; the amount of blood at the nostrils can range from small flecks incorporated in serous nasal discharge to large volumes flowing freely from both nostrils.

■ Pathophysiology Blood at the external nares originates from one or more of the following structures: nasal cavity, paranasal sinuses, guttural pouch (auditory tube diverticulum), oral cavity, pharynx, larynx, trachea, or lungs.⁴⁷ These respiratory structures may be affected by a primary disease process or may be one of many mucosal surfaces involved in a bleeding diathesis (Boxes 5.9 and 5.10). The actual disease condition, the affected structure, and the large animal species involved determine whether epistaxis is profuse or scant, unilateral or bilateral, induced by exercise, accompanied by hemoptysis, and/or associated with concurrent abnormal nasal discharge.

NASAL CAVITY OR PARANASAL SINUS PATHOLOGIC CONDI­TIONS. Epistaxis associated with diseased respiratory tract structures rostral to the caudal border of the nasal septum (e.g., nasal cavity, paranasal sinuses) is usually unilateral and appears spontaneously (i.e., occurs without exertion or lowering of the head). However, with profuse hemorrhage from these sites, blood may drain caudally, accumulate in the pharynx, and exit from both nostrils.

Nasal cavity structures are highly vascular and prone to injury. Bleeding can be caused by foreign bodies, fungal granulomas, or neoplasms that invade the nasal cavity; epistaxis associated with these lesions is commonly unilateral, scant, and evident only intermittently. Trauma induced by passage of a nasogastric tube or endoscope is the most common cause of profuse hemorrhage of nasal origin in horses.⁴⁷ Erosive diseases that affect the paranasal sinuses of horses (e.g., progres­sive ethmoidal hematoma)⁴⁷ or sheep (endemic nasal adeno­carcinoma)⁴⁹ commonly cause a unilateral, serosanguineous nasal discharge preceded or accompanied by mucopurulent discharge.

PATHOLOGIC CONDITIONS OF THE GUTTURAL POUCHES OF THE HORSE. Spontaneous epistaxis that occurs at rest in a mature horse warrants consideration of the guttural pouch as the source of hemorrhage.⁵⁰ In the case of guttural pouch mycosis, epistaxis is typically caused by fungal erosion of the internal carotid artery in the roof of the medial compartment of the guttural pouch.^50-52 The horse initially experiences several episodes of minor hemorrhage characterized by a small amount of fresh blood at the external nares; this may be preceded by a unilateral catarrhal nasal discharge and followed by a sero­mucous nasal discharge. Ultimately, massive arterial bleeding associated with erosion of the internal carotid artery manifests as large volumes of blood gushing from both nostrils.⁵¹ Epistaxis caused by bleeding from the guttural pouch is typically most pronounced on the ipsilateral side, but nasal bleeding is usually bilateral in this condition, especially if hemorrhage is profuse, because the nasopharynx drains into both nasal passages.⁵²

PULMONARY PATHOLOGIC CONDITIONS. In horses, pulmo­nary hemorrhage manifests as bilateral epistaxis, most often during or immediately after strenuous exercise.⁴⁷ In many cases of pulmonary hemorrhage, however, epistaxis is not observed

■ BOX 5.9

Causes of Epistaxis in Horses

Common Causes

Exercise-induced pulmonary hemorrhage (EIPH) Guttural pouch mycosis

Progressive ethmoidal hematoma

Nasal trauma

Pharyngeal or retropharyngeal trauma or abscess Nasal polyps

Tumors (nose, paranasal sinuses)

Foreign body (nasal, pharyngeal, laryngeal, tracheal, bronchial) Purpura hemorrhagica

Less Common Causes

Pleuropneumonia

Infarctive lobar pneumonia Pulmonary neoplasia

Fungal granuloma (maduromycosis, aspergillosis, rhinosporidi- osis, mycetoma)

Cryptococcal rhinitis Coccidioidomycosis Guttural pouch empyema Guttural pouch neoplasia Guttural pouch foreign body

Vesicular stomatitis

Atrial fibrillation

Idiopathic thrombocytopenic purpura Immune-mediated thrombocytopenia Lymphosarcoma

Myeloproliferative disease

Disseminated intravascular coagulation (DIC) Toxic hepatic failure

Multiple clotting defects (foals)

Equine infectious anemia (EIA) Skull fracture

Gunshot injury

Pharyngeal lymphoid hyperplasia

Uncommon Causes

Nasal amyloidosis Rectus capitis ventralis rupture Black disease (Clostridium novyi) Snakebite

Retrobulbar neoplasia

Chronic hepatitis or cholangitis Acute renal failure

Cardiac neoplasia Laryngeal hemiplegia Phycomycosis, pythiosis, zygomycosis Thrombasthenia-like syndrome Besnoitiosis, globidiosis (exotic) Dacryohemorrhea (exotic)

Toxic Causes

Arsenic

Warfarin or dicumarol

Stachybotryotoxicosis (Stachybotrys species) Plant toxins

Moldy sweet clover (Melilotus alba)

Pyrrolizidine alkaloid (e.g., common groundsel [Senecio vulgaris], fiddleneck [Amsinckia species], tansy ragwort [Senecio jacobaea])

because blood originating from the lungs is swallowed when it reaches the pharynx.

■ BOX 5.10

■ BOX 5.11

Causes of Epistaxis in Ruminants

Common Causes

Pharyngeal or retropharyngeal trauma or abscess

Lung embolus from caudal vena cava thrombosis (CVCT) (B) Infection of paranasal sinuses

Nasal trauma

Foreign body (nasal, pharyngeal, laryngeal, tracheal, bronchial) Nasal bots (Oestrus ovis) (C, O)

Nasal adenoma, adenopapilloma, adenocarcinoma (C, O) Dehorning of adult animals (B)

Less Common Causes

Nasal granuloma, atopic rhinitis (B)

Fungal granuloma (maduromycosis, rhinosporidiosis, mycetoma) (B, C)

Neoplasia (nose, paranasal sinuses) Skull fracture

Gunshot injury Bluetongue (O)

Vesicular stomatitis

Bovine virus diarrhea (BVD-MD) (B)

Malignant catarrhal fever (B)

Infectious bovine rhinotracheitis (IBR; BHV-1) (B)

Uncommon Causes

Black disease (Clostridium novyi) (B, O)

Acute anthrax (Bacillus anthracis)

Bacillary hemoglobinuria (Clostridium haemolyticum) (B, O) Snakebite

Acute renal failure

Endocarditis

Liver fluke disease

Pulmonary neoplasia Pasteurella pneumonia or septicemia (C, O) Xylazine-induced pulmonary edema (O)

Idiopathic granulocytopenia or thrombocytopenia (B) Hemophilia A (factor VIII deficiency) (B)

Factor XI deficiency (B)

Hereditary platelet aggregating disorder in Simmentals (B) Cardiomyopathy in polled Hereford calves (B) Trypanosomiasis (exotic) (B, O)

Ondiri disease (exotic) (B, O) Besnoitiosis, globidiosis (exotic) (B, O) Endemic ethmoid carcinoma (exotic) (B)

Gedoelstia hasleri nasal bots (exotic) (O, C) Nairobi sheep disease (exotic) (O, C)

Leech infestation (hirudiniasis) (exotic)

Toxic Causes

Mercury

Arsenic

Warfarin, diphacinone

Furazolidone

Trichloroethylene-extracted feed

Oak (acorn poisoning)

Bracken fern (Pteridium aquilinum) Moldy sweet clover (Melilotus alba) Phytogenous selenium poisoning (e.g., Astragalus species)

Oxalate poisoning (e.g., Halogen species, Sarcobatus species) Stachybotryotoxicosis (Stachybotrys species) Mycotoxicosis

B, Bovine; C, caprine; O, ovine.

Causes of Hemoptysis in Ruminants

Caudal vena cava thrombosis (CVCT)

Aspiration pneumonia

Pharyngeal or retropharyngeal abscess or trauma Thoracic trauma (fractured ribs or sternum)

Foreign body (nasal, oropharyngeal, tracheal, bronchial) Pulmonary aspergillosis

contrast to humans and other animal species, where foaming of blood exiting the nares suggests pulmonary hemorrhage, foaming of the blood is rarely encountered in horses with pulmonary hemorrhage because the horizontal position of the major bronchi allows blood to pool and flow freely without having to be coughed up.

EIPH, a syndrome experienced by 40% to 75% of Thor­oughbred racehorses and by horses of other breeds engaged in strenuous activity, is characterized by hemorrhage into the tracheobronchial tree during competitive exercise.^47,53,54 Although pulmonary hemorrhage can be identified by endo­scopic examination of the trachea immediately after exercise in these horses, EIPH manifests as frank epistaxis at the external nares in only a small percentage of cases.⁵³ Bleeding at the nares may range from a slight orange-tinged serous nasal discharge to a constant trickle of fresh blood that persists for several hours after exercise.^47,54 The exact source of hemorrhage in horses with EIPH has not been identified, but it is known that affected horses have proliferation of the bronchial arterial blood supply to the lungs.⁵⁵ Fatal massive epistaxis, an infrequent sequela to exercise, has been attributed to tearing of the lung in association with pleural adhesions or focal shear stress.⁵⁶ Other less common causes of postexercise pulmonary hemorrhage in horses include pulmonary abscesses or pleuropneumonia with pulmonary infarction; in these cases the odor of the breath may be fetid, and hemorrhage may occur spontaneously (without exercise), which aids in the differentiation of these conditions from EIPH.^47,57

Caudal vena cava thrombosis (CVCT; also known as pul­monary embolic aneurysm or pulmonary thromboembolism) is the disease most likely to be associated with epistaxis and hemoptysis in cattle (Box 5.11).⁵⁸ This sporadic, fatal condition of feedlot cattle is the result of a four-step sequence of events that cul­minates with the rupture of a pulmonary artery aneurysm into a bronchus.

Pulmonary edema present in the terminal stages of left-sided heart failure may also be responsible for bilateral serosanguine- ous discharge at the external nares of large animals.⁴⁷

PATHOLOGIC CONDITIONS OF THE ORAL CAVITY, PHARYNX, OR LARYNX. Less often, epistaxis can result from bleeding from lesions in the oral cavity, pharynx, or larynx. Examples include oral cavity erosions associated with infectious diseases (e.g., mucosal form of bovine virus diarrhea infection in cattle, bluetongue in sheep), erosions associated with epiglottic entrapment in horses, foreign bodies wedged in the mouth or pharynx of large animals, and pharyngeal or retropharyngeal trauma caused by a “balling gun.”

BLEEDING DIATHESIS. Several inherited and acquired coagulation disorders of large animals manifest as epistaxis.⁵⁹ Inherited clotting factor deficiencies (usually deficiencies of

factors VIII, IX, or XI) or acquired factor deficiencies (those caused by warfarin, sweet clover toxicosis, or advanced liver disease) cause bleeding from large vessels. In addition to epistaxis, subcutaneous hematomas, hemarthrosis, melena, hematuria, and prolonged bleeding from sites of injury may be observed. With conditions causing vasculitis (e.g., equine purpura hemorrhagica, equine viral arteritis), small vessel bleeding occurs. Vasculitis is characterized by mucous membrane petechiae and ecchymoses and demarcated areas of skin edema. Nasal mucous membrane petechiae associated with vasculitis may manifest as epistaxis. Similarly, thrombocytopenia (e.g., immune-mediated thrombocytopenia in horses, bracken fern toxicosis in cattle) is characterized by mucous membrane petechiae and occasionally epistaxis.

Approach to Diagnosis of Epistaxis and Hemoptysis

HISTORY. History information collected should closely follow that described for animals with nasal discharge and should include duration of ownership, time of first appearance of blood at the nares, number of times the animal has bled, volume and color of blood, presence of blood at one or both nostrils, association of epistaxis with exercise, swallowing motions or cough after exercise, concurrent hemoptysis, other signs of respiratory tract disease (e.g., stridor, cough, nasal discharge, respiratory distress), evidence of involvement of cranial nerves (e.g., feed particles at the nares, drooping of the lip or ear), possibility of recent trauma (e.g., nasogastric intubation, head injury), and exposure to toxic plants (e.g., bracken fern, sweet clover).

PHYSICAL EXAMINATION. A complete physical examination should be performed to detect abnormalities indicative of systemic disease or disease affecting other body systems. This examination should include assessment of the attitude of the animal; determination of rectal temperature, pulse rate, and respiratory rate and character; evaluation of mucous membranes for color and petechiae; inspection of the animal to detect hematomas or prolonged bleeding from sites of injury or venipuncture; and neurologic examination to detect neurologic dysfunction (e.g., dysphagia, Horner's syndrome, facial paralysis, head tilt, nystagmus), which may accompany guttural pouch mycosis.

EVALUATION OF THE HEAD AND RESPIRATORY SYSTEM. A complete evaluation of the head and respiratory system should also be carried out. The nasal bones and flat bones overlying the maxillary and frontal sinuses should be examined for asymmetry or deformation; the eyes should be evaluated for exophthalmos or epiphora; the nasal mucosae should be inspected with a light source to demonstrate erosive, ulcerative, or mass lesions; and the sinuses should be percussed to detect altered resonance or pain. On continuing the examination, the following should be evaluated: symmetry and amount of airflow through the nostrils and the effect of occluding each nostril independently, odor at the nose or mouth, presence of stridor, and the effect of applying pressure to the larynx or trachea. The oral cavity should be carefully inspected in animals in which epistaxis is accompanied by a necrotic breath odor. Special attention should be paid to the maxillary cheek teeth of horses and the base of the tongue and the oropharynx of all large animals. Structures in the external pharyngeal region (mandibular lymph nodes, Viborg's triangle, retropharyngeal lymph nodes, parotid salivary gland) should be observed and palpated for swelling, heat, or pain, and the trachea should be observed and palpated where exposed to detect any abnormalities. The larynx, trachea, and lungs should be carefully auscultated at rest and after application of a rebreathing bag for abnormally loud breath sounds, crackles, or wheezes, which may implicate pulmonary disease as the cause of epistaxis. Careful cardiac auscultation should be carried out to detect murmurs or dysrhythmias, which may be associated with left-sided heart failure and pulmonary edema. The chest wall should be palpated to detect rib fractures or pleural friction rubs, and the thorax should be percussed bilaterally to demonstrate large mass lesions, pleural effusion, or pleurodynia.

COMPLETE BLOOD COUNT. A complete blood count and assessment of fibrinogen concentration can be useful in the evaluation of animals with primary or secondary inflammatory conditions or those that have developed blood loss anemia as a sequela to epistaxis (e.g., horses with guttural pouch mycosis or cattle with pulmonary thromboembolism secondary to CVCT). The degree of anemia may give an indication of the severity and chronicity of the bleeding or, in cases of bracken fern poisoning, of the degree of bone marrow suppression.

CLOTTING PROFILE. A clotting profile should be performed (platelet count, prothrombin time [PT], activated partial thromboplastin time [APTT], concentration of fibrin degrada­tion products [FDPs], and plasma antithrombin III) if mucous membrane petechiae or a tendency to bleed was noted on the general physical examination or if the history suggests exposure

to sweet clover, warfarin, or bracken fern.

BIOCHEMISTRY PROFILE. A biochemistry profile should be performed to detect disease processes in organ systems other than the lungs (e.g., increased liver enzyme activity in cattle with hemoptysis secondary to CVCT or animals with liver failure causing secondary clotting factor deficiency).

OCCULT BLOOD. Feces should be tested for occult blood. Positive results may suggest swallowing of blood originating from the lungs or pharynx or gastrointestinal bleeding.

ENDOSCOPIC EVALUATION. Endoscopic evaluation is a useful diagnostic aid in cases of epistaxis. The nasal passages, naso­maxillary aperture in the middle meatus, turbinates (conchae), nasal septum, pharynx, guttural pouches, larynx, and tracheo­bronchial tree should be systematically evaluated through both nostrils at rest and after exercise if indicated to determine the presence, nature, and source of blood and the anatomic or mass lesion responsible for the bleeding. Care should be taken when endoscopy is performed in horses with guttural pouch mycosis because dislodging a clot of blood in the affected guttural pouch may result in fatal hemorrhage.⁶⁰ Similarly, the stress of endoscopy may prove fatal to cattle with pulmonary thromboembolism secondary to CVCT. If EIPH is suspected, endoscopy should be performed 30 to 120 minutes after strenuous exercise to allow time for the mucociliary escalator to transport blood to where it can be visualized⁵³; this blood may persist from 6 hours to 4 days after exercise, depending on the severity of pulmonary hemorrhage. It is important to remember that EIPH may not be repeatable. In one study only 33% of Thoroughbred racehorses tested positive for EIPH on all subsequent endoscopic examinations after breezing.⁶¹ Biopsy (with histologic evaluation and possibly culture of samples) is indicated when granulomas, polyps, erosions, or mass lesions are visualized through the endoscope.

TRACHEAL ASPIRATION, BRONCHOALVEOLAR LAVAGE, AND THORACOCENTESIS. Percutaneous transtracheal aspiration or endoscopic tracheal aspiration, BAL, or thoracocentesis with cytologic studies and culture of collected samples is indicated when pulmonary or pleural diseases are thought to be responsible for hemorrhage into the respiratory tract^20,21,62-64 (see the Cough section earlier). The presence of hemosidero- phages in tracheobronchial aspirates or BAL fluid is generally considered indicative of previous pulmonary hemorrhage⁵³; however, mucopolysaccharides engulfed by alveolar macrophages can bind plasma iron in the absence of pulmonary hemorrhage to form an iron pigment resembling hemosiderin.⁶⁴

RADIOGRAPHIC EXAMINATION. Radiographic examination of the nasal passages, paranasal sinuses, pharynx, retropharyngeal region (including the guttural pouches), larynx, and trachea is indicated if the source of nasal bleeding cannot be definitively diagnosed through physical examination and endoscopy. The nasal passages, turbinates, and paranasal sinuses should be evaluated for fluid lines, cystic structures, bony lysis or prolifera­tion, distortion of normal architecture, or changes in the tooth roots. Space-occupying lesions in the pharynx and larynx may also be demonstrated by radiographic examination. Demonstra­tion of a fluid-air interface in the guttural pouch may indicate guttural pouch hemorrhage or guttural pouch empyema.⁴⁷ New bone formation and sclerosis around the temporohyoid articulation (temporohyoid osteoarthropathy) may accompany mycotic infection of the guttural pouch but also occurs in the absence of mycotic infection.⁴⁷ CT examination may be indicated if the lesion in the head or neck causing hemorrhage cannot be defined adequately with plain radiographs. Thoracic radiographs using four overlapping lateral views in adult horses and cattle and lateral and ventrodorsal views in immature animals and small ruminants aid in identification and definition of diseases affecting the lungs, pleurae, and mediastinum.²⁰

ULTRASOUND EXAMINATION. See the Cough section earlier.

PARACENTESIS. Paracentesis of the maxillary sinuses²⁰ can be performed if percussion and inspection indicate that a lesion in the maxillary sinus may be the cause of epistaxis (see the Nasal Discharge section earlier).

PLEUROSCOPIC EXAMINATION. Pleuroscopic examination⁶⁵ is rarely indicated in the evaluation of epistaxis and should be limited to cases in which a disease process involving the pleura (e.g., pleural neoplasia, pleuropneumonia with pulmonary infarctions) is strongly suspected based on the results of other diagnostic tests and a diagnosis cannot be reached by less invasive approaches (see the Cough section earlier).