Upper respiratory tract Notes

Contents

Osmosis High-Yield Notes

This Osmosis High-Yield Note provides an overview of Upper respiratory tract essentials. All Osmosis Notes are clearly laid-out and contain striking images, tables, and diagrams to help visual learners understand complex topics quickly and efficiently. Find more information about Upper respiratory tract:

Bacterial epiglottitis

Laryngitis

Nasal polyps

Retropharyngeal and peritonsillar abscesses

Sinusitis

Upper respiratory tract infection

NOTES NOTES UPPER RESPIRATORY TRACT GENERALLY, WHAT IS IT? DIAGNOSIS PATHOLOGY & CAUSES ▪ Upper-airway infection (e.g. nasal cavity, pharynx, larynx) with pathogenic microbes RISK FACTORS ▪ Compromised immunity; genetic, congenital malformations; concomitant infection LAB RESULTS ▪ Cultures, complete blood count (CBC) ▫ Bacterial involvement OTHER DIAGNOSTICS ▪ Clinical presentation, physical exam COMPLICATIONS TREATMENT ▪ Airway obstruction, infection spread, sepsis SIGNS & SYMPTOMS ▪ Stridor; fever (if bacterial infection); discharge; difficulty swallowing MEDICATIONS ▪ Antimicrobials SURGERY ▪ Surgical interventions OTHER INTERVENTIONS ▪ Respiratory support, intubation (if severe respiratory obstruction) 946 OSMOSIS.ORG
Chapter 133 Upper Respiratory Tract BACTERIAL EPIGLOTTITIS osms.it/bacterial-epiglottitis PATHOLOGY & CAUSES ▪ Inflammation of epiglottis, nearby supraglottic structures ▪ Fluid, inflammatory-cell accumulation → rapid, progressive swelling of epiglottis, adjacent structures (supraglottic larynx) → airway narrows, ball-valve curling → airway obstruction CAUSES ▪ Bacteria from posterior nasopharynx, Haemophilus influenzae (most common in children), Streptococcus pneumoniae, Staphylococcus aureus RISK FACTORS ▪ Unimmunized status ▪ Mucosal trauma ▫ E.g. burns, caustic substance/foreign body ingestion ▪ Most common in children 6–12 years old ▪ Comorbidities (adults) ▫ E.g. diabetes mellitus, substance abuse, BMI > 25 COMPLICATIONS ▪ ▪ ▪ ▪ Airway obstruction Oropharyngeal secretion aspiration Cardiopulmonary arrest High mortality rate anterior neck tenderness, anxiety DIAGNOSIS DIAGNOSTIC IMAGING Laryngoscopy ▪ Swollen, red epiglottis X-ray ▪ Shadow of enlarged epiglottis (“thumb” sign); ballooning of hypopharynx LAB RESULTS ▪ CBC: ↑ white blood cells (WBCs) ▪ ↑ C-reactive protein (CRP), positive throat culture TREATMENT MEDICATIONS ▪ Empiric antimicrobial therapy ▫ E.g. third generation cephalosporin for Haemophilus influenzae colonization OTHER INTERVENTIONS ▪ Airway management with humidified supplemental oxygen Prevention ▪ Haemophilus Influenzae Type b (Hib) vaccine SIGNS & SYMPTOMS ▪ Children: abrupt “3Ds” onset: dysphagia, drooling, distress ▪ Respiratory: stridor, retractions, tachypnea, cyanosis ▪ Behavioral: individual refuses to lie down; assumes tripod posture ▪ Voice: aphonia, muffled ▪ Other: sore throat, fever, odynophagia, OSMOSIS.ORG 947
LARYNGITIS osms.it/laryngitis PATHOLOGY & CAUSES ▪ Inflammation of larynx ▫ Acute: < three weeks ▫ Chronic: > three weeks CAUSES Acute ▪ Viral ▫ Rhinovirus, influenza virus, parainfluenza, adenovirus ▪ Bacterial ▫ Moraxella catarrhalis, H. influenzae, S. pneumoniae ▪ Fungal ▫ Candida in immunosuppressed ▪ Trauma, nerve damage Chronic ▪ Acid reflux, smoke exposure, allergies, rheumatoid arthritis, autoimmune disease SIGNS & SYMPTOMS ▪ Flu-like ▫ Fever, cough, malaise, enlarged lymph nodes ▪ Stridor, hoarseness, pain, odynophagia, lump in throat 948 OSMOSIS.ORG DIAGNOSIS DIAGNOSTIC IMAGING Laryngoscopy ▪ Swollen, red vocal folds; biopsy LAB RESULTS ▪ Blood culture TREATMENT MEDICATIONS ▪ Simple analgesics ▪ Non-steroidal anti-inflammatory drugs (NSAIDs) ▪ If bacterial infection, antibiotics OTHER INTERVENTIONS ▪ Voice rest
Chapter 133 Upper Respiratory Tract NASAL POLYPS osms.it/nasal-polyps PATHOLOGY & CAUSES ▪ Overgrowths of epithelial tissue lining nasal cavity, paranasal sinuses ▪ Most commonly formed in maxillary/ ethmoid sinus ▪ Results in airflow obstruction, mucus drainage blockage DIAGNOSIS DIAGNOSTIC IMAGING Endoscopy ▪ Direct visualization of nasal polyp CT scan ▪ Hyperdense outpouching in nasal cavity CAUSES ▪ Unknown; associated with long-term inflammatory sinus conditions ▫ Seasonal allergies, frequent asthma exacerbations, chronic sinusitis, aspirin sensitivity RISK FACTORS ▪ Cystic fibrosis, primary ciliary dyskinesia COMPLICATIONS ▪ Mucus drainage obstruction; sinusitis → recurrent infections TREATMENT MEDICATIONS Topical steroids ▪ Nasal spray to shrink polyp; ↓ inflammation, swelling Nasal saline lavage ▪ Underlying allergy treatment SURGERY ▪ Endoscopic sinus surgery if unresponsive to steroids SIGNS & SYMPTOMS ▪ May be asymptomatic ▪ Bacterial infection ▫ Blocked mucus drainage ▫ Fever, headache ▪ Obstructed air flow ▫ ↓ sense of smell, snorting, sleep apnea, cyanosis (in infants) OSMOSIS.ORG 949
Figure 133.1 The histological appearance of a nasal polyp. There is loose, myxoid stroma lined by respiratory epithelium. Figure 133.2 A trans-nasal view of a polyp in the posterior nasal passage. RETROPHARYNGEAL & PERITONSILLAR ABSCESS osms.it/rp-and-pt-abscess PATHOLOGY & CAUSES ▪ Abscesses of the upper respiratory tract TYPES Retropharyngeal abscess ▪ Abscess formation in retropharyngeal space ▫ Between buccopharyngeal fascia, alar fascia ▪ Bacteria of nasopharynx enter weakened mucosa → white blood cells (WBCs) follow, create pus → mass grows, pushes into airway Peritonsillar abscess ▪ Pus in potential space between pharyngeal muscles, palatine tonsils CAUSES Retropharyngeal abscess ▪ Bacterial ▫ S. aureus, group A beta-hemolytic bacteria, H. parainfluenzae ▪ Trauma, upper respiratory tract infections Peritonsillar abscess ▪ Streptococcus pyogenes (most common) → acute tonsillitis ▪ Staphylococcus, Haemophilus, anaerobes of mouth flora (less common) COMPLICATIONS Retropharyngeal abscess ▪ Spread beyond retropharyngeal space, mediastinitis, pericarditis; pharyngitis, airway obstruction; sepsis Peritonsillar abscess ▪ Retropharyngeal abscess, cellulitis of head and neck, sepsis 950 OSMOSIS.ORG
Chapter 133 Upper Respiratory Tract SIGNS & SYMPTOMS ▪ Fever, lethargy, swelling, sore throat Retropharyngeal abscess ▪ Neck pain/stiffness, pharyngeal obstruction, difficulty swallowing, dyspnea, cough, stridor Peritonsillar abscess ▪ Asymmetric tonsillar swelling with uvular displacement; lymph node enlargement ▪ Muffled voice, trismus, sleep disturbance (difficult breathing), snoring, halitosis DIAGNOSIS DIAGNOSTIC IMAGING Contrast CT scan ▪ Tissue swelling Figure 133.3 Clinical appearance of a right sided peritonsillar abscess which shows swelling of the palatopharyngeal arch. Ultrasound ▪ Differentiate Peritonsillar abscess from Cellulitis LAB RESULTS ▪ Systemic spread in CBC, throat culture, blood culture OTHER DIAGNOSTICS Clinical presentation ▪ Swollen pharyngeal space tissues ▪ Redness, asymmetry TREATMENT MEDICATIONS ▪ IV antibiotics Figure 133.4 A CT scan of the head in the axial plane demonstrating a peritonsillar abscess. SURGERY ▪ Surgical drainage of abscess ▪ Peritonsillar abscess ▫ If airway obstruction, immediate tonsillectomy/incision, drainage OSMOSIS.ORG 951
SINUSITIS osms.it/sinusitis PATHOLOGY & CAUSES ▪ Inflammation of sinuses, usually due to infection LAB RESULTS ▪ CBC, leukocytes often normal ▪ Swabs, cannulation contraindicated due to high likelihood of sample contamination TREATMENT CAUSES ▪ Influenza, parainfluenza, rhinoviruses, adenoviruses; bacteria of nasopharynx RISK FACTORS ▪ Upper respiratory tract infections, allergies, teeth infections (spread to maxillary sinus), tumors, adenitis, nasotracheal/nasogastric tubes, genetic disorders (Kartagener, cystic fibrosis), deformation of bone COMPLICATIONS ▪ Meningitis, cavernous sinus thrombosis, orbital/periorbital cellulitis, abscesses SIGNS & SYMPTOMS MEDICATIONS Antibiotics ▪ If bacterial ▪ First line treatment, penicillin (amoxicillin with clavulanic acid); second line, fluoroquinolones Corticosteroids (topical/systemic) ▪ Alleviate allergies OTHER INTERVENTIONS Steam treatments ▪ Dislodge secretions ▪ Bacterial ▫ Fever, headache, immediately previous upper respiratory infection, feeling of draining fluid, pain when leaning forward, voice change, last > 10 days ▪ Viral ▫ Self-limiting, painful sinuses (esp. leaning forward), discharge, last < 10 days DIAGNOSIS DIAGNOSTIC IMAGING ▪ Rare CT scan ▪ Screen for complications 952 OSMOSIS.ORG Figure 133.5 A CT scan of the head in the coronal plane demonstrating left maxillary sinusitis.
Chapter 133 Upper Respiratory Tract UPPER RESPIRATORY TRACT INFECTION osms.it/upper-resp-tract-infection PATHOLOGY & CAUSES Pharyngitis ▪ Clinical syndrome characterized by sore throat, cervical lymphadenopathy; sore throat worsens with swallowing; typically accompanied by reactive enlargement of tonsils ▪ Inflammation of nasopharyngeal mucosa with reactive inflammation of lymph nodes, tonsils The common cold ▪ Mild self-limiting viral infection characterized by nasal congestion, rhinorrhea, sore throat, nonproductive cough, low grade fever ▪ Most common upper respiratory tract infection ▪ Hand contact/inhalation of airborne droplets from infected individual → viral inoculation → deposition on nasal mucosa → viral replication → cytokines release from infected cells → immune response initiates → inflammation, congestion of nasal cavity mucous membranes ▪ Resolves within one week, symptoms last up to 10–14 days; esp. in young children < six ▪ No cross immunity between serotypes ▫ Possible reinfection with milder symptoms, shorter duration CAUSES Pharyngitis ▪ Infectious ▫ Most common pathogens: respiratory viruses (rhinovirus, echovirus, adenovirus, coronavirus), Group A Streptococcus pyogenes (GAS) ▫ Less common pathogens: bacteria (Staphylococcus aureus; Group C, G Streptococcus; Arcanobacterium haemolyticum; Fusobacterium necrophorum; Mycoplasma pneumoniae; Chlamydia pneumoniae; Corynebacterium diphtheriae; Neisseria gonorrhoeae; Treponema pallidum); viruses (respiratory syncytial viruses; influenza A, B; HIV; Epstein–Barr virus; cytomegalovirus; herpes simplex virus; parainfluenza; enteroviruses) ▪ Noninfectious ▫ Allergic rhinitis ▫ Irritative pharyngitis (due to dry air, esp. in winter) ▫ Medications (e.g. angiotensinconverting enzyme inhibitors) ▫ Kawasaki disease ▫ Periodic fever, aphthous stomatitis, pharyngitis, adenitis (PFAPA) syndrome The common cold ▪ Viruses ▫ Most common: rhinoviruses (50% of all cases) ▫ Coronaviruses, parainfluenza viruses, RSV, influenza, adenoviruses, coxsackie viruses RISK FACTORS The common cold ▪ Age, usually children < six; malnutrition; underlying diseases; immunodeficiency disorders; smoking; stress; sleep disturbances; weather, high prevalence in fall, winter COMPLICATIONS Pharyngitis ▪ Severe pharyngeal inflammation, abscess formation, tonsillar hypertrophy → upper OSMOSIS.ORG 953
airway obstruction ▪ Post streptococcal ▫ Suppurative (spread of infection beyond pharynx): otitis media; peritonsillar cellulitis/abscess; retropharyngeal abscess; sinusitis; meningitis; bacteremia; necrotizing fasciitis; jugular vein septic thrombophlebitis ▫ Non suppurative (immune mediated): acute rheumatic fever, which can progress to rheumatic heart disease; post streptococcal glomerulonephritis; reactive arthritis; scarlet fever (delayed skin reactivity to erythrogenic toxin produced by GAS; requires prior exposure to GAS; characteristic scarlet rash, white with red enlarged papillae aka “strawberry tongue”); streptococcal toxic shock syndrome; pediatric autoimmune neuropsychiatric disorder associated with streptococcus (PANDAS) ▪ Lemierre syndrome: suppurative thrombophlebitis of jugular vein caused by Fusobacterium necrophorum The common cold ▪ Secondary bacterial infection ▫ Acute otitis media, sinusitis, pneumonia ▪ Asthma exacerbation SIGNS & SYMPTOMS Pharyngitis ▪ Reddening; edema of pharyngeal mucosa; sore throat, worsens when swallowing ▪ Neck pain/swelling due to reactive lymphadenopathy ▫ Not prominent in viral pharyngitis ▫ Prominent, tender, anterior cervical lymphadenopathy in bacterial pharyngitis ▪ Constitutional symptoms ▫ Fever (low grade in viral pharyngitis, high grade in bacterial pharyngitis) ▫ Headache, fatigue, malaise ▪ Swollen, reddened tonsils with white spots of exudate from tonsillar crypts ▪ Suggestive of ▫ Viral pharyngitis: cough, nasal congestion, conjunctivitis, coryza, oral 954 OSMOSIS.ORG ulcer, viral exanthem ▫ Bacterial pharyngitis: sudden onset of symptoms, high grade fever, tonsillopharyngeal edema, tonsillar exudates, painful cervical lymphadenopathy ▪ Symptoms resolve within 3–5 days in viral pharyngitis; 5–7 days in bacterial pharyngitis The common cold ▪ Immune response to infection ▪ Nasal features ▫ Congestion; clear, purulent, yellow/green discharge; sneezing; erythema, nasal mucosa swelling ▪ Nonproductive cough ▪ Sore throat ▪ Low grade fever ▫ Predominant in young children; uncommon in older children, adults ▪ Headache, malaise, abnormal middle ear pressure, conjunctivitis DIAGNOSIS LAB RESULTS Pharyngitis ▪ If suggestive of GAS pharyngitis (AKA strep throat) ▫ Rapid strep test (RST): detects GAS antigens on swab sample of tonsils, posterior pharynx ▫ Throat culture: more accurate than RST, takes 24 hours. If RST negative, but clinical suspicion of GAS pharyngitis; beta hemolytic, bacitracin sensitive, pyrrolidonyl arylamidase (PYR) positive colonies ▫ Polymerase chain reaction (PCR)-based assays: more sensitive, rarely available ▫ Serological tests: (antistreptococcal antibodies: anti-streptolysin (ASO), antihyaluronidase, anti-streptokinase, antinicotinamide adenine dinucleotidase, anti-DNase; ↑ titres suggestive of recent GAS infection; useful for detecting post streptococcal complications
Chapter 133 Upper Respiratory Tract OTHER DIAGNOSTICS Pharyngitis ▪ Oropharyngeal examination ▪ Centor criteria: predict possibility of GAS pharyngitis ▫ 1 point each: fever, tonsillar exudates, tender anterior cervical lymphadenopathy, absence of cough, age < 15; subtract 1 point if age > 44 ▫ -1, 0, 1: no testing ▫ 2, 3: testing required ▫ 4, 5: empirical antibiotic treatment The common cold ▪ Clinical presentation ▪ Re-evaluation if symptoms worsen/exceed expected recovery time TREATMENT ▫ Chronic tonsillitis unresponsive to antibiotics ▫ Tonsil enlargement causing airway obstruction ▫ Complications of pharyngotonsillitis ▫ PFAPA syndrome OTHER INTERVENTIONS Pharyngitis ▪ Viral pharyngitis often self-limited ▪ Symptomatic ▫ Rest ▫ Adequate fluids to loosen secretions, prevent airway obstruction The common cold ▪ Symptomatic ▫ Rest ▫ Adequate fluids MEDICATIONS Pharyngitis ▪ Antipyretics/analgesics ▫ Aspirin, acetaminophen, nonsteroidal anti-inflammatory drugs (NSAIDs); for fever, pain control ▪ Salt water gargling ▪ GAS pharyngitis: antibiotics to prevent complications, reduce symptoms, prevent transmission ▫ First line treatment: penicillin (penicillin V/amoxicillin) ▫ Alternatives: cephalosporins, clindamycin, macrolides ▫ If recurrent/persistent: repeat 10 day course of antibiotics The common cold ▪ Topical saline/nasal suction/combination of nasal decongestant with antihistamines ▪ Antipyretics/analgesics ▪ Dextromethorphan/codeine to suppress cough SURGERY Pharyngitis ▪ Tonsillectomy ▫ Recurrent infections OSMOSIS.ORG 955

Osmosis High-Yield Notes

This Osmosis High-Yield Note provides an overview of Upper respiratory tract essentials. All Osmosis Notes are clearly laid-out and contain striking images, tables, and diagrams to help visual learners understand complex topics quickly and efficiently. Find more information about Upper respiratory tract:

Bacterial epiglottitis

Laryngitis

Nasal polyps

Retropharyngeal and peritonsillar abscesses

Sinusitis

Upper respiratory tract infection