What Is a Chronic Ear Infection?
Ear infections are usually secondary to inflammation of the external ear canals (the tube-shaped part of the ear visible under the ear flap). Inflammation of the canals leads to the reproduction of normal bacteria and yeast that live in the ear to the point where the body is unable to control their numbers (called overgrowth). Other bacteria can also take advantage of the inflammation and unhealthy environment inside the ear to establish infection. The overgrowth of these organisms causes more inflammation. Inflammation of the ear canal causes swelling, making the tube narrower than usual. Inflammation also causes an increase in the production of wax. The ears become very itchy and painful. Severe ear infections can lead to eardrum rupture and middle and inner ear infections. Deep infections can lead to deafness and neurologic signs.
Certain disorders or diseases may be the primary reason ear infections develop. These conditions include:
- Allergies (environmental and food)
- Ear mites
- Foreign bodies
- Skin disorders (like seborrhea)
- Thyroid disease (in dogs)
- Tumors or polyps in the ear
Ear infections may recur because of the inability to control the original infection or treat the underlying cause. Chronic changes lead to future infections, and scar tissue and permanent narrowing of the ear canals can make future infections difficult to treat.
What Are the Signs of an Ear Infection?
An external ear infection first shows signs of local inflammation (redness, discharge). Pets may shake their heads, scratch their ears, or rub their ears against furniture or the floor. Some pets with severe infections may cry or groan as they rub and scratch their ears. Some pets scratch so severely that their nails create wounds on the skin around their face, neck, and ears.
External ear infections may progress to involve the middle and inner ear, leading to more serious signs of disease:
- External ear infection (otitis externa)
- Itchy or painful ears
- Head shaking
- Discharge and odor from the ears
- Narrowing or even closing of the canals
- Middle ear infection (otitis media)
- Paralysis of the nerves in the face
- Dry eye
- Hearing loss
- Abnormal pupil size
- Inner ear infection (otitis interna)
- Inability to keep balance, stand, or walk
- Head tilt
How Is an Ear Infection Diagnosed and Treated?
During a physical examination, your veterinarian will look in the ear for the presence of inflammation, redness, discharge, growths, or other findings that may indicate an ear infection. Sometimes, a cotton swab is used to collect debris from the ear. This material can be placed on a slide and examined under a microscope to determine if the infection is due to yeast, bacteria, or mites. Your veterinarian may also collect a sample of ear debris for culture and sensitivity testing, which identifies the exact organisms present and helps your veterinarian select the best antibiotic to use.
In severe cases, or if the animal is in too much pain to permit an examination of the ears, sedation may be needed to evaluate the ears, collect samples of discharge, clean the ears, and initiate treatment. With the pet sedated, the ears can be gently flushed to remove debris and facilitate better examination of the ear. Radiographs (X-rays) and other diagnostic tests can be performed while the pet is sedated to determine if the middle or inner ear are also involved.
Once the infection has been identified, most animals with chronic ear infections can be treated at home. Ear mites are relatively easy to treat with medication placed directly into the ear or applied topically between the shoulder blades. Most yeast and bacterial infections can be treated with regular cleanings and topical or oral medication. When inflammation is severe, a steroid may be needed to give comfort to your pet and decrease the swelling around the ear canals.
If there are underlying problems such as thyroid disease or seborrhea, these must also be addressed to clear the infection and reduce the chances of recurrence.
If the ear canals have been permanently narrowed or damage is otherwise severe, surgery may be recommended to allow for drainage and application of medication. In other cases, more extensive surgery may be recommended to prevent the pet from being in chronic pain due to a permanently deformed, infected ear.
How Can Ear Infections Be Prevented?
Once an infection has been cleared, maintaining a healthy ear environment with regular cleaning helps prevent recurrence. Unfortunately, regular cleaning isn’t always enough. Underlying diseases such as allergies and skin disorders must be identified and resolved in order to help avoid future infections.
Conjunctivitus in Dogs and Cats
Dogs and cats alike can be affected by conjunctivitis, an inflammation of the tissues surrounding the inner eyelids and white part of the eyes that sometimes accompanies a respiratory infection or eye injury. It can also be brought on by airborne irritants, dry eye, or a more serious illness such as canine distemper or feline herpesvirus.
Symptoms include goopy or bloodshot eyes, swollen eyelids, and rubbing of the eyes. Treatment ranges from eye drops and ointments to surgery in rare cases.
Conjunctivitis is the medical term used to describe inflammation of the conjunctiva — the soft tissues that line the inside of the eyelids and the white portion of the eye.
Conjunctivitis can occur as part of an upper respiratory tract infection, a condition that resembles a common cold. It can also be associated with a localized problem that causes trauma to or irritation of the eyes. Causes include:
- Airborne irritants, such as cigarette smoke, dust, and perfumes
- Systemic illnesses (illnesses that affect the whole body), such as feline herpesvirus, feline immunodeficiency virus (FIV), canine distemper, and bartonellosis (infection with the bacteria that cause “cat scratch disease” in humans)
- Dry eye (aka, keratoconjunctivitis sicca) a medical condition characterized by inadequate tear production)
- Entropion (a malformation of the eyelids that causes the edges of the lids to roll inward; the hairs on the eyelids scrape against the eye and cause irritation)
- Trauma to the eye, such as a blow
The severity of conjunctivitis will vary dramatically from case to case. Only rarely will blindness result.
Symptoms and Identification
The clinical signs of conjunctivitis vary depending on the severity of the inflammation. Signs include:
- Discharge from the eyes (can be pus, watery, or thick, like mucus)
- Swollen eyelids
- Red, “bloodshot” eyes
- Rubbing the eyes with a paw or against other objects, such as furniture or the floor
If the conjunctivitis is severe, permanent damage to the cornea (the clear covering on the surface of the eye) can occur.
The medical history and physical examination findings can provide valuable information for your veterinarian. The medical history may include trying to determine how long the conjunctivitis has been going on and whether any other signs of illness have been observed. Physical examination findings may reveal evidence of underlying illness. For example, a cat with an upper respiratory tract infection may have a runny nose, sneezing, and a fever in addition to conjunctivitis.
Diagnosis of conjunctivitis is usually based on physical examination findings. If a pet is squinting because his/her eyes are painful, a veterinarian will often begin the examination by applying a drop of liquid topical anesthetic directly to the eye. This is not painful, and after a few minutes, it numbs the surface of the eye so the examination can proceed. During the examination, the veterinarian will likely look for foreign material, wounds, or other causes of conjunctivitis. Entropion can also be diagnosed during the physical examination.
While examining the pet’s eyes, the veterinarian will often instill fluorescein stain. Fluorescein is a green-tinted dye that fluoresces (glows) under blue light. If the surface of the cornea is intact, the fluorescein dye will not stick to the eye. However, if there is a scratch, ulcer, or wound on the cornea, the dye adheres to the defect and can show your veterinarian where and how serious the injury is. Fluorescein staining is not painful and can provide valuable information about the condition of a pet’s eye.
Testing to determine if tear production is adequate is typical in cases where dry eye (keratoconjunctivitis sicca) is suspected. Similarly, if a systemic illness (such as FIV) is suspected, blood testing or other diagnostic tests may be recommended.
Any dog or cat can develop conjunctivitis.
Most cases of conjunctivitis are treated with drops or ointments applied directly to the eyes. If the conjunctivitis is associated with another illness, like an upper respiratory infection, antibiotics or other medication given by mouth may also be recommended. In many cases, the eye starts looking better after only a few treatments. However, all medications should be given as directed for the full course of treatment.
If the conjunctivitis is associated with entropion, surgery may be recommended to correct the deformed eyelid. Similarly, if a pet has dry eye, long-term management may be recommended to control the condition.
A veterinarian will typically recommend recheck exams during the course of treatment to monitor how well the condition is responding to therapy. Rarely, a pet will require surgery to remove the eye to prevent further pain, inflammation, and infection.
Many causes of conjunctivitis are preventable. For example, minimizing exposure to airborne irritants like cigarette smoke, monitoring pets during play and exercise to reduce the risk of trauma to the eye, and keeping pets current on vaccinations against diseases that can cause conjunctivitis, such as feline herpes virus and canine distemper can reduce the likelihood of developing conjunctivitis associated with these causes.