Phys review-- otitis media .pdf

Otitis media Disease summary: ○ Definition: acute otitis media (AOM) is defined as any inflammation of the middle ear regardless of specific cause or pathogenesis ○ The term acute refers to a short and painful infection with rapid onset of symptoms...

Otitis media Disease summary: ○ Definition: acute otitis media (AOM) is defined as any inflammation of the middle ear regardless of specific cause or pathogenesis ○ The term acute refers to a short and painful infection with rapid onset of symptoms ○ Acute otitis media can be classified into many variants based on cause and clinical manifestations ○ However, it is most commonly a pediatric bacterial infection of the middle ear that is usually precipitated by a virally induced upper respiratory tract infection ○ The accumulation of fluid and mucus in the auditory tube predisposes the middle ear to a secondary bacterial infection ○ The patient typically presents with otalgia (i.e., earache), a sensation of increased pressure within the ear, loss of hearing and fever Prevalence: ○ Although it may occur at any age, AOM is most common in infants and children (80-90% of all cases before 6 years of age) ○ Peak prevalence in both genders occurs between ages 6-18 months ○ Some studies show bimodal prevalence peaks ○ A second, lower peak occurs at ages 4-5 years and corresponds with entry into school ○ Recent well-controlled studies suggest that AOM prevalence is the same in boys and gisl that there is no difference in incidence between blacks and whites in the US ○ Second only to upper respiratory infection, AOM is the most common disease of childhood and the most common cause for childhood visits to a physician’s office ○ The illness accounts for approximately 20 million physician visits annually ○ Acute otitis media is also the most frequent specific diagnosis rendered in children who are febrile ○ Approximately half of all children have an episode of AOM before their first birthday, and four or five children develop the condition by age 3 years ○ Furthermore, one third of children who have reached 7 years of age have experienced a minimum of six episodes of AOM SIgnificance ○ Although an ear infection is not considered a medical emergency, AOM can be extremely painful, especially for the first 24 hours after onset ○ Furthermore, interpreting pain in a child too young to communicate verbally can be a challenge for the healthcare provider ○ Acute otitis media in this era of antimicrobial therapy, mortality rates due to AOM are extremely low (1 death/100,000 cases) ○ However, despite the frequent use of systemic antibiotics to treat the illness, morbidity from this disease remains significant. ○ If AOM does not clear completely, the infection can spread into the mastoid bone behind the ear and causes mastoiditis or develop into a persistent condition for at least 6 weeks (i.e., chronic otitis media) in which acute episodes flare intermittently ○ Long-lasting or recurrent infections can damage the eardrum, bones of the ear, and middle ear structures and have the potential to cause permanent hearing loss.  Causes and risk factors ○ The most common bacterial pathogen in AOM is: Streptococcus pneumoniae followed by Haemophilus influenzae and Moraxella catarrhalis. ○ These three microbes are responsible for 95% of all cases of AOM with a bacterial etiology. ○ In infants younger than 6 weeks, gram negative bacilli (e.g., Escherichia coli, Klebsiella species, and Pseudomonas aeruginosa) play a much larger role as etiologic agents, causing one in five cases ○ Viruses most commonly associated with AOM are respiratory syncytial virus, influenza viruses, parainfluenza viruses, rhinovirus, and adenovirus. ○ Since children have eustachian tubes that are usually narrower than those of an adult and an immature immune system, all children are susceptible to middle ear infections. However, some children are at especially high risk. ○ Children at highest risk include: those attending childcare centers (especially with more than six children) ○ genetic factors (Susceptibility to infection may run in families, however, no specific genes have been linked to vulnerability to AOM at this time.) ○ change in altitude ○ cold climate ○ Socioeconomic status includes many independent factors that affect risk In general, lower socioeconomic status confers higher risk for: environmental exposure to cigarette smoke bottle feeding crowded group daycare and living conditions Diagnosis: Clinical Manifestations and Lab tests ○ Acute otitis media should be suspected in children with otalgia, otorrhea (i.e., discharge from the ear), headache, concurrent or recent upper respiratory infection symptoms (such as cough, rhinorrhea, or sinus congestion), lethargy, difficulty sleeping, or gastrointestinal manifestations (such as anorexia, nausea, vomiting, or diarrhea). ○ Young children may show signs of otalgia by tugging on an affected ear. ○ Otalgia occurs more often when the child is lying down, which may be due to increased eustachian tube dysfunction. ○ Irritability may be the sole early symptom in a young infant or toddler. ○ Symptoms of more advanced AOM include hearing loss, tinnitus (i.e., ringing in the ears), vertigo (i.e., room-spinning dizziness), unsteadiness and clumsiness ○ Rupture of the TM is accompanied by a sudden decrease in pain, followed by the onset of otorrhea. ○ A normal TM is pale gray in color and translucent. ○ A dark pink or light red TM is consistent with the inflammatory process that occurs with AOM. ○ An opaque yellow or blue TM is consistent with fluid within the middle ear. ○ Dark red suggests blood behind the TM.  ○ Redness of the TM alone does not necessarily indicate AOM, because crying, removal of cerumen (i.e., earwax) with associated irritation of the auditory canal, coughing, nose blowing, and fever can all cause redness of the eardrum without a middle ear infection, indicating an air-filled space. ○ A TM that moves only slightly with both positive and negative pressure applied indicates the probable presence of middle ear fluid ○ The position of the TM (i.e., bulging, retracted, neutral) is also key to distinguishing AOM from other ear disorders. ○ The TM is usually in the neutral position (i.e., neither retracted nor bulging). ○ In AOM, the TM is usually bulging. ○ In fact, bulging of the TM is the single greatest predictive sign when evaluating the presence of fluid in the middle ear ○ Abnormal movement of the TM (i.e., abnormal mobility) during pneumatic otoscopy can suggest various ear conditions. ○ A normal TM responds briskly to both positive and negative pressure, If Mastoiditis does occur: 1. The ear is usually displaced laterally and forward. 2. There is palpable tenderness with erythema over the postauricular area. 3. This indicates that the infection has spread from the middle ear cavity to the mastoid space. ○ Perforation of the TM is a frequent, but usually not serious, complication. ○ With proper treatment, most perforations heal without residual effects within 2 weeks The use of antibiotics may also cause side effects such as nausea, diarrhea, rash, and other allergic reactions, some of which can be life threatening. Furthermore, frequent use of antibiotics may create strains of antibiotic-resistant bacteria that make future infections more difficult to treat. Over-the-counter pain relievers, such as ibuprofen or acetaminophen, are often effective for otalgia. However, aspirin should not be given to children younger than 16 years of age because the drug may cause a life threatening condition known as Reye syndrome. Infants younger than 6 months should always receive antibiotics, despite diagnostic certainty and disease severity. Children ages 6 months to 2 years should receive antibiotics when the diagnosis is certain