UPPER RESPIRATORY INFECTIONS (URIs)

BACKGROUND

The upper respiratory tract includes the sinuses, nasal passages, pharynx, and larynx. These structures direct the air we breathe from the outside to the trachea and eventually to the lungs for respiration to take place.

An upper respiratory tract infection, or upper respiratory infection, is an infectious process of any of the components of the upper airway. Infection of the specific areas of the upper respiratory tract can be named specifically. Examples of these may include:

• Rhinitis (inflammation of the nasal cavity)
• Sinus infection (sinusitis or rhinosinusitis) - inflammation of the sinuses located around the nose
• Common cold (nasopharyngitis) - inflammation of the nares, pharynx, hypopharynx, uvula, and tonsils
• Pharyngitis (inflammation of the pharynx, uvula, and tonsils)
• Epiglottitis (inflammation of the upper portion of the larynx or the epiglottis)
• Laryngitis (inflammation of the larynx)
• Laryngotracheitis (inflammation of the larynx and the trachea), and
• Tracheitis (inflammation of the trachea).

Upper respiratory infections are one of the most frequent causes for a doctor visit. Although upper respiratory infections can happen at any time, they are most common in the fall and winter months, from September until March.

DISEASE OCCURRENCE IN POPULATION:

URIs is the most common infectious illness in the general population and is the leading cause of missed days at work or school. They represent the most frequent acute diagnosis in the office setting.

RISK FACTORS:

Not everybody exposed to or who comes into direct contact with an ill person will "catch" their cold. People are especially susceptible if there is a decrease in the body's immune system so that the virus can begin to spread within the body and cause symptoms in the body.

Some common risk factors for upper respiratory infection are:

• physical or close contact with someone with a upper respiratory infection
• poor hand washing after contact with an individual with upper respiratory infection
• close contact with children in a group setting, schools or daycare centers
• contact with groups of individuals in a closed setting, such as, traveling, tours, cruises
• smoking or second-hand smoking (may impair mucosal resistance and destroy the cilia)
• health care facilities, hospitals, nursing homes

• When humidity is low. Indoor heating favors survival of many viruses that cause URIs.
• immunocompromised state (compromised immune system) such as,HIV, organ transplant, congenital immune defects, long term steroid use; and
• anatomical abnormalities as in facialtrauma, upper airway trauma, nasal polyps.

SIGN AND SYMPTOMS:

Generally, the symptoms of upper respiratory infection result from the toxins released by the pathogens as well as the inflammatory response mounted by the immune system to fight the infection.

Common symptoms of upper respiratory infection generally include:

• nasal congestion
• runny nose (rhinorrhea)
• nasal discharge (may change from clear to white to green)
• trouble breathing
• breathing much faster than usual
• sneezing
• sore or scratchy throat
• painful swallowing (odynophagia)
• cough (from laryngeal swelling and post nasal drip)
• malaise, and
• fever (more common in children).

Other less common symptoms may include

• foul breath
• reduced ability to smell (hyposmia)
• headache
• shortness of breath
• sinus pain
• itchy and watery eye (conjunctivitis)
• nausea
• vomiting
• diarrhea, and
• body aches.

Some of the common complications of upper respiratory infections are the following:

• respiratory compromise from epiglottitis;
• secondary infection by bacteria (viral infection can cause impairment of the physical barrier in the respiratory airways making it easier for bacteria to invade) resulting in bacterial sinusitis, bronchitis, pneumonia;
• formation of abscesses in the tonsils;
• rheumatic fever from strep throat;
• spread of infection from sinuses to the brain (meningitis);
• involvement of the ears resulting in middle ear infections (otitis media);
• worsening of underlying chronic lung disease (asthma, COPD);
• spread of infection to the heart (pericarditis, myocarditis);
• spread of the infection to the brain or the fluid around the brain causing encephalitis or meningitis; and
• muscular pain and rib fractures from forceful coughing.

DIAGNOSTIC TEST:

The diagnosis of upper respiratory infection is typically made based on review of symptoms, physical examination, and occasionally, laboratory tests.

In physical examination of an individual with upper respiratory infection, a doctor may look for swollen and redness inside wall of the nasal cavity (sign of inflammation), redness of the throat, enlargement of the tonsils, white secretions on the tonsils (exudates), enlarged lymph nodes around the head and neck, redness of the eyes, and facial tenderness (sinusitis). Other signs may include bad breath (halitosis), cough, voice hoarseness, and fever.

Laboratory testing is generally not recommended in the evaluation of upper respiratory infections. Because most upper respiratory infections are caused by viruses, specific testing is not required as there is typically no specific treatment for different types of viral upper respiratory infections.

Some important situations where specific testing may be important include:

• Suspected strep throat (fever, lymph nodes in the neck, whitish tonsils, absence of cough), necessitating rapid antigen testing (rapid strep test) to rule in or rule out the condition given possible severe sequelae if untreated.
• Possible bacterial infection by taking bacterial cultures with nasal swab, throat swab, or sputum.
• Prolonged symptoms, as finding a specific virus can prevent unnecessary use of antibiotics (for example, rapid testing for the influenza virus from nasal or pharyngeal swabs).
• Evaluation of allergies and asthma which can cause long lasting or unusual symptoms.
• Enlarged lymph node and sore throat as the primary symptoms that may be caused by Ebstein-Barr virus (mononucleosis) with expected longer time course (by using the monospot test).
• Testing for the H1N1 (swine) flu if suspected.

Blood work and imaging tests are rarely necessary in the valuation of upper respiratory infection. X-rays of the neck may be done if suspected case of epiglottitis. Although the finding of swollen epiglottis may not be diagnostic, its absence can rule out the condition. CT scans can sometimes be useful if symptoms suggestive of sinusitis last longer than 4 weeks or are associated with visual changes, copious nasal discharge, or protrusion of the eye. CT scan can determine the extent of sinus inflammation, formation of abscess, or the spread of infection into adjacent structures (cavity of the eye or the brain)

TREATMENT OPTIONS:

Rest is an important step in treating upper respiratory infections. Usual activities, such as, working and light exercising may be continued as much as tolerated.

Increased intake of oral fluids is also generally advised to keep up with the fluid loss from runny nose, fevers, and poor appetite associated with upper respiratory infections

Treatment of the symptoms of upper respiratory infection is usually continued until the infection has resolved.

Some of the most common upper respiratory infection or cold medications used to treat these symptoms are the following:

• Acetaminophen can be used to reduce fever and body aches.
• Non-steroidal anti-inflammatory drugs such as ibuprofen can be used for body aches and fever.
• Antihistamines such as diphenhydramine are helpful in decreasing nasal secretions and congestions.
• Nasal ipratropium (topical) can be used to diminish nasal secretions.
• Cough medications (antitussives) can be used to reduce cough. Many cough medications are commercially available such as dextromethorphan, guaifenesin , and codeine all have shown benefits in reducing cough in upper respiratory infections.
• Honey can be used in reducing cough.
• Steroids such as dexamethasone and prednisone orally (and nasally) are sometimes used reduce inflammation of the airway passage and decrease swelling and congestion.
• Decongestants such as pseudoephedrine Actifed oral, phenylephrine can be used to reduce nasal congestion (generally not recommended in children less than 2 years of age and not recommended for individuals with high blood pressure).
• Oxymetazoline nasal solution is a decongestant, but should only be used for short-term.
• Combination medications containing many of these components are also widely available over the counter.

Some cough and cold medicines can cause excessive drowsiness need to be used with caution in children younger than 4 years of age and the elderly.

Antibiotics are sometimes used to treat upper respiratory infections if a bacterial infection is suspected or diagnosed. These conditions may include strep throat, bacterial sinusitis, or epiglottitis. Antivirals may occasionally be recommended by doctors in patients who are immunocompromised (poor immune system). The treating doctor can determine which antibiotic would be the best option for a particular infection.

Because antibiotics are associated with many side effects and can promote bacterial resistance and secondary infections, they need to be used very cautiously and only under the direction of a treating physician.

Inhaled epinephrine is sometimes used in children with severe spasm of the airways (bronchospasm) and in croup to reduce spasm.

Rarely, surgical procedures may be necessary in cases of complicated sinus infections, compromised airway with difficulty breathing, formation of abscesses behind the throat, or abscess formation of the tonsils (peritonsillar abscess).

PRECAUTIONS:

There are several measures that can reduce the risk of infections in general. Smoking cessation, reducing stress, adequate and balanced diet, and regular exercise are all measures that can improve the immune system and reduce the overall risk of infections. Breastfeeding also helps strengthen the immune system of infants by transferring the protective antibodies from the mother's milk to the baby.

Other preventive measures to diminish the risk of spread of upper respiratory infections are:

• hand washing is especially encouraged during the cold seasons (fall and winter) or handling others with the infection;
• reducing contact with people who may have the infection (people may carry and spread the virus a few days before they have symptoms and a few days after their symptoms have resolved);
• proper cleaning of common objects that are touched by individuals who may be infectious such as, telephones, refrigerator door, computers, stair railings, door handles, etc.;
• covering mouth and noise when coughing or sneezing; and
• vaccination with flu vaccine as recommended for certain people (elderly, people with chronic medical conditions, health care workers, etc.).

Moist warm air can help soothe the oral and nasal passages that become more irritated with dry air. This can make breathing easier and nasal secretions looser and easier to discharge. Some simple ways to do this are:

• making steam in the shower by turning on the hot water (without going under it) and breathing the steamed air;
• drinking warm beverages (hot tea, hot chocolate, warm milk);
• using a vaporizer to create humidity in the room; and
• avoid cold, dry air if possible.

Nasal saline (salt water) can help with symptoms of nasal congestion. There are over the counter saline spray solutions available that can be used for this purpose. Simpler and more cost effective home-made salt water solution may also be considered. A forth of a teaspoon of salt can be added to 8 oz cup of room temperature water and stirred to dissolve. Using a bulb syringe or a small spray bottle, the solution may be applied in one nostril at time with slow inhalation and expelled with exhalation several times a day as needed.

Salt water gurgles and lozenges may reduce throat irritation and dryness and can alleviate the symptoms of throat symptoms.

Cough can be suppressed by limiting exposure to irritants, such as, cold whether, cigarette smoke, dust, and pollution. Sleeping in a semi-upright position may be helpful at time to reduce cough.

Adequate hydration with water, juices, and non-caffeinated drinks can thin nasal secretions and replace the fluid losses.

REFERENCES:

• http://patient.info/health/common-cold-and-other-upper-respiratory-tract-infections
• http://www.medicinenet.com/upper_respiratory_infection/page14.htm
• http://www.medicinenet.com/upper_respiratory_infection/article.htm
• Cherry DK, Hing E, Woodwell DA, Rechtsteiner EA. National Ambulatory Medical Care Survey: 2006 Summary. 2008. Available at http://www.cdc.gov/nchs/data/nhsr/nhsr003.pdf.