Upper respiratory tract Notes
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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 by visiting the associated Learn Page.