4/17 URI: iBook Ch 9 Flashcards
Define Pharyngitis
What agents cause it?
What is the most important distinction to make in diagnosing Pharyngitis?
An inflammatory syndrome of the pharynx caused by several types of organisms.
Predominant causes are viral but can also be due to bacterial and atypicals.
Most impt distinction: Group A Strep (bacteria) vs all other causes (primarily viral)
Common cold: cardinal symptoms?
- Nasal discharge and obstruction
- Sneezing
- Sore/scratchy throat
- Nonproductive cough with sensation of postnasal drip
Common cold: physical findings?
Avg duration of illness?
- Red nares with clear discharge, “glassy” nasal membranes
- Throad injected wiht mucus on posterior pharyngeal wall; no exudate
- No or mild fever (<1’ elevation)
- Duration ~1 week, will last 3d longer in smokers
Common cold: most common cause? next most common?
Seasons most prevalent?
- Rhinovirus (HRV) is most common followed by coronavirus
- Rhinovirus prevalent in fall/spring; coronavirus and RSV in winter
Common cold: incubation period? at what point is maximal viral excretion?
Incubation is 48-72 h
Max viral excretion coincides with peak of clinical illness, but begins 1 day before, and may persist over a week.
Common cold: most effective transmission?
- hand to hand transmission more efficient than droplet spread for rhinovirus. may persist on fomites (contaminated object or surface) for several hours.
- influenza, parainfluenza, adenovirus, coxsackievirus transmit via aerosol
Common cold: where does replication of rhinovirus occur?
-What are the major mediators of symptoms?
Rhinovirus replicates in nasal epithelium, but does not cause much destruction.
-Symptoms are mainly due to immune response of host: mainly kinins
Common cold: diagnosis?
Clinical diagnosis (viral cultures not readily avail)
-Challenge is to distinguish bacterial conditions (infrequent; treatable) from viral illness (more common; self-limited)
Common cold: treatment?
Symptomatic treatment!
- Rhinorrhea: intranasal ipratropium bromide or cromolyn sodium to reduce volume and severity
- Sore throat: ibuprofen, warm saline gargles
- couth: antitussives
- systemic sx: rest, ibuprofen
- Decongestants
Common cold: treatments that are NOT effective?
antibiotics, Vit C, echinacea, antihistamines, expectorants, glucocorticoids, zinc
Common cold in kids: what should I avoid giving them? why?
Avoid aspirin use in children with URI
May cause Reye’s Syndrome
[potentially fatal; affects many organs, especially the brain and liver. Also –> hypoglycemia. Classic features: rash, vomiting, liver damage.
Exact cause unknown. Has been associated with aspirin consumption by children with viral illness; also occurs in the absence of aspirin use.]
Common cold: 3 possible complications?
Frequency of these complications?
- Sinusitis. occurs in 40% of adults w cold sx.
- Acute Otitis media. Primarily occurs in kids; 50-80% of adults develop Eustachian tube dysfunction.
- Lower resp tract disease. In adults, up to 40% of acute asthma attacks are secondary to colds.
Group A ß-hemolytic streptococcal pharyngitis (GABHS): symptoms?
- Abrupt onset
- Sore throat, pain w swallowing
- Systemic illness: fever, malaise
- Nasal congestion/cough in 50% (not prominent)
Group A ß-hemolytic streptococcal pharyngitis (GABHS): Physical findings?
- temps of 100-104
- Diffuse redness of pharynx and tonsils (may be bright red)
- Tonsillar exudate in 50-80% (patchy or confluent)
- Enlarged, tender anterior cervical lymph nodes
Group A ß-hemolytic streptococcal pharyngitis (GABHS): what are the factors leading to infection?
Group A ß-hemolytic strep causes what % of sore throats in adults? kids?
Exact factors leading to infection are unknown: may be altered host immunity, bacterial interference, elaboration of enzymes (streptokinase, hyaluronidase, proteinase) by virulent strains.
Group A ß-hemolytic strep: 10% of sore throats in adults & 25% in kids.
Group A ß-hemolytic strep: diagnosis?
Two methods:
- Culture: throat swab –> agar. look for beta-bemolysis. Type with a latex agglutination assay. (false neg 5%)
- Rapid enzyme immunoassay. Preferred for clinical diagnosis; allows prompt treatment.
Group A ß-hemolytic strep: why is it impt to accurately identify the Group A strep?
- prevent the immune-medient sequela of rheumatic fever (potential –> heart disease)
- prevent suppurative complications (peritonsillar abscess)
Group A ß-hemolytic strep: how can we estimate the probability of Group A strep infection?
Three clinical clues: tonsillar exudates, enlarged tender cervical LNs, temp > 100.
If all three sx present, probability of Group A strep infection = 42%.
How can we decrease the occurence of acute rheumatic fever in suspected Group A strep?
Can decrease rheumatic fever 10x by starting antibiotics within 9d of onset of sx. Continue for 10d of treatment overall.
Antibiotics can also reduce symptoms, suppurative complications, and infectious spread.
Group A ß-hemolytic strep: what antibiotics to use?
- Oral penicillin V
- Benzathine penicillin via single IM injection if compliance is problematic
- If PCN allergy, Erythromycin, clarithroymycin, azithromycin
Group A ß-hemolytic strep: meds for symptoms?
- For sore throat, fever & systemic sx: acetominophen
- Severe sore throat: acetaminophen w Codeine or viscous Xylocaine
Mononucleosis: symptoms?
Onset?
Pharyngitis/laryngitis
Fever, headache, malaise, fatigue
Abrupt onset or several day prodrome
Mononucleosis: Physical findings?
Fever
Adenopathy: both cervical and generalized
-Splenomegaly (50%)
Mononucleosis: Etiology?
Majority: EBV.
Also: CMV, HIV
EBV: how is it spread?
(remember this is the main cause of mono)
spread by intimate contact with oropharyngeal secretions.
Can persist up to 18m after clinical recovery.
EBV: what are peak periods of seroconversion?
severity of clinical illness increases w what?
Peak periods of seroconversion are 0-5 yrs and in the 20s
Severity of clinical illness increases with age.
Mononucleosis: Diagnosis?
- Clinical syndrome
- Hematologic findings: Lymphotycosis; Atypical lymphocytosis = hallmark; thrombocytopenia
- Heterophile antibodies (antibodies that agglutinate sheep erythrocytes). Commercial test “Monospot” available.
- EBV antibodies
Mononucleosis: Treatment?
Treatment = symptomatic
Occasionally give steroids for airway obstruction, severe thrombocytopenia, hemolytic anemia
define acute bronchitis.
how does it contrast with chronic bronchitis?
acute inflammatory condition of the tracheobronchial tree that does not involve the pulmonary parenchyma
contrast w chronic: chronic has significant sputum production on most days during at least 3 months each of 2 consecutive years (who comes up this stuff??!!). also contrasts with acute exacerbation of chronic bronchitis (AECB)
Acute Bronchitis: Cardinal Symptoms?
- Persistent cough (days to weeks)
- Possible sputum production
- Possible fevers
Acute Bronchitis: Physical Findings?
- Cough
- Possible fevers (most likely with Influenza, Adenovirus, Mycoplasma)
- Lung exam: crackles or wheezes, no consolidation
Acute Bronchitis: Etiology? (what pathogens?)
Which pathogens are most important/treatable? (2)
Majority of cases are viral.
Most important (and treatable) are Mycoplasma pneumoniae and Chlamydia pneumoniae
Bordetella pertussis should be considered with appropriate epidemiology