CMS150 Clinical Medicine Week 1 PDF

CMS150 CLINICAL MEDICINE WEEK 1 JANUARY 2023 LEARNING OUTCOMES Differentiate between causes of acute pharyngitis Know the relative frequencies of the causes of acute pharyngitis and how they vary based on patients' epidemiological characteristics Understand the potential harms of physical examinatio...

CMS150 CLINICAL MEDICINE WEEK 1 JANUARY 2023 LEARNING OUTCOMES Differentiate between causes of acute pharyngitis Know the relative frequencies of the causes of acute pharyngitis and how they vary based on patients' epidemiological characteristics Understand the potential harms of physical examination in a patient with acute pharyngitis Identify signs and symptoms that suggest urgent and emergent conditions in a patient with acute pharyngitis WEEK 1: THE CASE OF ALEX BEST 14-year-old adolescent CC: recent onset SORE THROAT SORE THROAT = PHARYNGITIS Inflammation of the pharynx DURATION OF SORE THROAT Acute are normally infectious causes Acute pharyngitis – less than 2 weeks duration Chronic pharyngitis – more than 2 weeks duration Could be other chronic things, GERD, etc IN OUR CASE, RECENT ONSET We have a case of acute pharyngitis CAUSES OF PHARYNGITIS: AN OVERVIEW Causes of Pharyngitis Noninfectious Causes Infectious Causes Viral Bacterial Infection is the most common cause of sore throat Viral > bacterial Causes of Pharyngitis INFECTIOUS PHARYNGITIS Sore throat caused by an infection Viral Bacterial Fungal Infectious Causes Fungal pharyngitis is rare Consider in patients: Viral Bacterial Who are immunocompromised With chronic steroid or antibiotic use - Rhinovirus Coronavirus Adenovirus Herpes simplex virus (HSV) Influenza A and B Parainfluenza virus Epstein-Barr virus Cytomegalovirus Human herpesvirus (HHV) 6 HIV Causes of Pharyngitis Infectious Causes Viral VIRAL PHARYNGITIS Infection of pharynx by a virus Most common cause: common cold At least 25% of cases due to rhinoviruses and coronaviruses Causes of Pharyngitis Infectious Causes - Group A beta-hemolytic streptococci (GABHS) - Fusobacterium necrophorum - Group C beta-hemolytic streptococci - Neisseria gonorrhoeae - Corynebacterium diphtheriae - Mycoplasma pneumoniae - Chlamydophila pneumoniae Bacterial BACTERIAL PHARYNGITIS Infection of pharynx by bacteria Most common cause: Group A beta-hemolytic streptococci (GABHS) 5-15% of sore throats in adults 20-30% sore throats in children (ages 5-15) Class Viruses Infection Rhinovirus Coronavirus Adenovirus Herpes Simplex Virus (HSV) 1 and 2 Influenza A and B Parainfluenza virus Epstein-Barr virus (EBV) Cytomegalovirus (CMV) HIV Group A beta-hemolytic streptococci Fusobacterium necrophorum Frequency1 20% 5% 5% 4% 2% 2% < 1% < 1% < 1% 15–30% 10% Clinical Syndrome Common cold Common cold Acute respiratory disease Stomatitis, pharyngitis Influenza Common cold, croup Infectious mononucleosis Infectious mononucleosis Primary HIV infection Bacteria Pharyngitis, tonsillitis Pharyngitis, peritonsillar abscess, Lemierre syndrome (rare) Group C beta-hemolytic streptococci 5% Pharyngitis, tonsillitis Neisseria gonorrhoeae < 1% Pharyngitis Corynebacterium diphtheriae < 1% Diphtheria Mycoplasma pneumoniae < 1% Pneumonia, bronchitis Chlamydophila pneumoniae Unknown Pneumonia, bronchitis Table 30-1.Frequency and clinical syndrome for infectious causes of sore throat. 1Estimated percentage of cases in all ages, prevalence estimates are sensitive to the population studied. Source: Symptom to Diagnosis: An Evidence-Based Guide, 4e Source: Canadian Family Physician Jul 2011, 57 (7) 791-794 Causes of Pharyngitis NON-INFECTIOUS PHARYNGITIS Consider in patients: With chronic sore throat Without signs of infection Who do not respond to treatment Noninfectious Causes - Persistent cough - Upper airway cough syndrome (postnasal drip) - Gastroesophageal reflux disease - Acute thyroiditis - Neoplasm Tumor - Allergies - Smoking - Rhinovirus Coronavirus Adenovirus Herpes simplex virus (HSV) Influenza A and B Parainfluenza virus Epstein-Barr virus Cytomegalovirus Human herpesvirus (HHV) 6 HIV Causes of Pharyngitis Noninfectious Causes Infectious Causes Viral Bacterial - Persistent cough - Upper airway cough syndrome (postnasal drip) - Gastroesophageal reflux disease - Acute thyroiditis - Neoplasm - Allergies - Smoking - Group A beta-hemolytic streptococci (GABHS) - Fusobacterium necrophorum - Group C beta-hemolytic streptococci - Neisseria gonorrhoeae - Corynebacterium diphtheriae - Mycoplasma pneumoniae - Chlamydophila pneumoniae GENERAL APPROACH TO ACUTE PHARYNGITIS Rule out serious diagnoses and red flags/alarm symptoms that prompt emergent/urgent management Most cases of acute pharyngitis are due to infectious cause – determine the specific infectious cause (i.e., viral or bacterial) Identify acute sore throat caused by group A betahemolytic streptococcal (GABHS) pharyngitis Antibiotic treatment may be indicated BACK TO THE CASE OF ALEX BEST: 14-year-old adolescent CC: recent onset SORE THROAT Rule out serious conditions and red flags/alarm symptoms WHAT IS A RED FLAG OR ALARM SYMPTOM/SIGN? Red flags are signs and symptoms found in the patient history and clinical examination that may indicate possible serious underlying pathology. Red flags prompt further investigation and/or referral. Symptoms B Difficulty swallowing Sore throat, dysphagia, or & Pain when swallowing odynophagia with any of the following: Drooling SERIOUS Respiratory distress D I A G N O S E S Inability to open mouth fully A N D A L A R M (trismus) Lock jaw S Y M P TO M S Muffled voice Stiff neck Erythema of neck - - History of recent foreign body impaction or oropharyngeal procedure (trauma) Serious Diagnoses Acute epiglottitis or supraglottitis Peritonsillar abscess Parapharyngeal space infection Retropharyngeal space infection Submandibular space infection (Ludwig's angina) Superficial jugular thrombophlebitis (Lemierre syndrome). Retropharyngeal abscess Fever, rash, diffuse adenopathy, Primary HIV infection sore throat Swollen lymph nodes systemically G Recent cocaine smoking Potential Complications Airway obstruction; sepsis; spread to parapharyngeal or retropharyngeal spaces, with subsequent spread to pleura, mediastinum, carotid sheath, or jugular vein Airway obstruction; sepsis; spread to mediastinum, pleural space, or pericardium Transmission of disease Mucosal burn injury to pharynx Respiratory obstruction and larynx Weight loss, fevers, night sweats Lymphoma, head and neck Advanced malignancy cancers Source: The Patient History, 2e ACUTE EPIGLOTTITIS Rare but potentially fatal condition Inflammation of epiglottis and adjacent tissues Bacterial infection primarily caused by Haemophilus influenzae In the past, most commonly seen in children aged 2-6 HiB vaccination in infants has decreased incidence Most common in winter and spring Positive thumb sign on lateral radiograph of the neck is diagnostic Medical emergency → refer! Airway management is key to prevent airway compromise May require intubation Requires antibiotic therapy ACUTE EPIGLOTTITIS Clinical Presentation Acute onset fever, severe sore throat, toxic appearance They look tired, overall unwell Y The 4 Ds: Dysphagia (difficulty swallowing) Drooling Dysphonia (muffled, hoarse, abnormal voice) Distress (inspiratory stridor, tripod position, severe dyspnea, irritability, restlessness) Do not use a tongue depressor when examining the oropharynx as it can precipitate airway obstruction PERITONSILLAR ABSCESS = around = collection of pus Aka quinsy Most common deep infection of head and neck (30% of abscesses of head and neck) Most common in young adults (ages 20-40); increased risk in immunocompromised and diabetics Usually begins as acute tonsillitis → cellulitis → abscess formation Polymicrobial infection Common organisms: Group A streptococci, Staphylococcus aureus, Haemophilus influenzae, Fusobacterium, Peptostreptococcus, Pigemented Prevotella species, Veillonella Diagnosis can be made clinically without labwork/imaging in patients with typical presentation PERITONSILLAR ABSCESS Clinical Presentation Severe unilateral sore throat Dysphagia and odynophagia → pooling of saliva or drooling Fever and malaise Dysphonia: muffled “hot potato” voice Rancid or fetor breath Otalgia Ear pain Trismus (66% of patients) (Watch this video for an example of what “hot potato” voice sounds like: https://www.youtube.com/watch?v= 5KMlx1XXtCM) Lock jaw Oropharyngeal exam: erythematous enlarged tonsil and bulging soft palate on affected side, uvular deviation to contralateral side May have severely tender cervical lymphadenopathy O - Tonsillar swelling Early Peritonsillar Abscess. Edema and marked erythema of the left tonsillar pillar in early peritonsillar abscess. (Photo contributor: Kevin J. Knoop, MD, MS.) Citation: 5-17 Peritonsillar Abscess, Knoop KJ, Stack LB, Storrow AB, Thurman R. The Atlas of Emergency Medicine, 5e; 2021. Available at: https://accessmedicine.mhmedical.com/content.aspx?sectionid=250456208&bookid=2969 Copyright © 2022 McGraw-Hill Education. All rights reserved Peritonsillar Abscess. Acute peritonsillar abscess showing medial displacement of the uvula, palatine tonsil, and anterior pillar. (Photo contributor: Lawrence B. Stack, MD.) Citation: 5-17 Peritonsillar Abscess, Knoop KJ, Stack LB, Storrow AB, Thurman R. The Atlas of Emergency Medicine, 5e; 2021. Available at: https://accessmedicine.mhmedical.com/content.aspx?sectionid=250456208&bookid=2969 Copyright © 2022 McGraw-Hill Education. All rights reserved PERITONSILLAR ABSCESS Culture of pus from abscess drainage confirms diagnosis Imaging not necessary to confirm diagnosis CT with IV contrast (LR+ 4, LR- 0) Intraoral ultrasonography (sensitivity 89-95%, specificity 79100%) Treatment includes drainage, antibiotic therapy, supportive care RETROPHARYNGEAL ABSCESS Behind the throat Pus forming Retropharyngeal edema due to cellulitis and suppurative adenitis of Infection of lymph lymph nodes in retropharyngeal space nodes Preceded by upper respiratory infection, pharyngitis, otitis media, wound infection following penetrating injury to posterior pharynx Peak incidence in 3-5 year olds Observed as prevertebral soft-tissue thickening on lateral X-ray of neck Treat as impending airway emergency Requires antibiotic therapy, possible surgical consultation for needle aspiration or incision and drainage RETROPHARYNGEAL ABSCESS Clinical Presentation Sore throat and dysphagia Difficulty swallowing Fever Drooling Dysphonia (muffled voice) Neck stiffness; limited neck ROM (especially hyperextension) Stridor Whistling noise when breathing in May see bulging of the posterior wall of oropharynx on clinical examination BACK TO THE CASE OF ALEX BEST: 14-year-old adolescent CC: recent onset SORE THROAT No red flags present Gather more information to determine if an infectious cause is likely ALEX IS FEBRILE There is variation across references and populations for normal body temperature ranges, but the general consensus is that body temperature (oral, rectal, tympanic or temporal artery measurement) over 38°C (100.4°F) is considered a fever FEVER STRONGLY SUGGESTS INFECTIOUS CAUSE OF PHARYNGITIS WHAT TYPE OF INFECTION COULD IT BE? Source: Canadian Family Physician Jul 2011, 57 (7) 791-794 VIRAL PHARYNGITIS Most pharyngitis cases are viral in origin Associated symptoms that are more likely to present with viral illness: cough, nasal congestion, conjunctivitis, hoarseness, diarrhea, oropharyngeal lesions (ulcers or vesicles) Viruses that are most likely to cause pharyngitis in children: Common cold (50%) – caused by rhinovirus, coronavirus, adenovirus, parainfluenza virus, respiratory syncytial virus Influenza (5%) – caused by Influenza virus (type A and B) most commonly Mononucleosis (5%) – caused by Epstein-Barr Virus (EBV), cytomegalovirus (CMV) Viral causes of pharyngitis do not require antibiotic therapy unless there is a secondary bacterial infection BACK TO THE CASE OF ALEX BEST: 14-year-old adolescent CC: recent onset SORE THROAT Febrile – suggests infectious cause Identify acute sore throat caused by group A beta-hemolytic streptococcal (GABHS) pharyngitis Antibiotic therapy may be indicated STREPTOCOCCAL PHARYNGITIS aka “strep throat”, GABHS pharyngitis Infection of pharynx caused by group A beta-hemolytic streptococci (GABHS) Most common in children aged 5-15 Risk factors: exposure to sick contact with GABHS, winter or early spring Typical Presentation Acute onset fever and sore throat Headache, nausea, vomiting, malaise, dysphagia, abdominal pain Cough and rhinorrhea usually absent (presence suggests more viral cause) Edema and erythema of tonsils and pharynx; non-adherent tonsillar and/or pharyngeal exudate Enlarged and tender anterior cervical lymph nodes 1 in 10 cases of streptococcal pharyngitis may evolve into scarlet fever: scarlatiniform rash and strawberry tongue May have palatine petechiae This image depicts a close intraoral view of a child’s inflamed oropharynx, which also included the patient’s soft palate, as well as tonsillitis, all which had been caused by group A Streptococcus (GAS) bacteria. These bacteria are spread through direct contact with mucus from the nose or throat of persons, who are infected, or through contact with infected wounds, or sores on the skin. https://phil.cdc.gov//PHIL_Images/6375/6375_lores.jpg Strep pharyngitis showing tonsillar exudate and erythema. (Reproduced with permission from Richard P. Usatine, MD.) Citation: Chapter 37 Pharyngitis, Usatine RP, Smith MA, Mayeaux, Jr. EJ, Chumley HS. The Color Atlas and Synopsis of Family Medicine, 3e; 2019. Available at: https://accessmedicine.mhmedical.com/content.aspx?bookid=2547&sectionid=206778481 Copyright © 2022 McGraw-Hill Education. All rights reserved Scarlatiniform rash in scarlet fever. This 7-year-old boy has a typical sandpaper rash with his strep throat and fever. The erythema is particularly concentrated in the axillary area. (Reproduced with permission from Richard P. Usatine, MD.) Citation: Chapter 37 Pharyngitis, Usatine RP, Smith MA, Mayeaux, Jr. EJ, Chumley HS. The Color Atlas and Synopsis of Family Medicine, 3e; 2019. Available at: https://accessmedicine.mhmedical.com/content.aspx?bookid=2547&sectionid=206778481 Copyright © 2022 McGraw-Hill Education. All rights reserved Strawberry tongue in a child with scarlet fever caused by strep pharyngitis; note marked erythema and prominent papillae. (Reproduced with permission from Richard P. Usatine, MD.) Citation: Chapter 36 Scarlet Fever and Strawberry Tongue, Usatine RP, Smith MA, Mayeaux, Jr. EJ, Chumley HS. The Color Atlas and Synopsis of Family Medicine, 3e; 2019. Available at: https://accessmedicine.mhmedical.com/content.aspx?bookid=2547&sectionid=206778435 Copyright © 2022 McGraw-Hill Education. All rights reserved This image depicts an intraoral view of a patient, who had presented to a clinical setting exhibiting redness and edema of the oropharynx, and petechiae, or small red spots, on the soft palate. A diagnosis of strep throat had been made, caused by group A Streptococcus bacteria. https://phil.cdc.gov//phil_images/20030214/13/PHIL_3185_lores.jpg Overlapping presentation with viral pharyngitis Viral pharyngitis with visible palatal petechiae. Palatal petechiae can be seen in all types of pharyngitis. (Reproduced with permission from Richard P. Usatine, MD.) Viral pharyngitis in a young adult showing enlarged cryptic tonsils with some erythema and exudate. (Reproduced with permission from Richard P. Usatine, MD.) Citation: Chapter 37 Pharyngitis, Usatine RP, Smith MA, Mayeaux, Jr. EJ, Chumley HS. The Color Atlas and Synopsis of Family Medicine, 3e; 2019. Available at: https://accessmedicine.mhmedical.com/content.aspx?bookid=2547&sectionid=206778481 Accessed: December 15, 2022 Copyright © 2022 McGraw-Hill Education. All rights reserved COMPLICATIONS Don’t involve pus! Non-suppurative complications Acute rheumatic fever (ARF) – rare in North America More common in children than adolescents and adults In Canada, 0.1 to 2 cases per 100,000 Higher in remote, Canadian Indigenous communities (Northern Ontario 8.33/100,000) Risk may be higher in immigrants from endemic areas (e.g., Philippines, China) In USA, 3000-4000 cases of GABHS pharyngitis need to be treated to prevent 1 case of ARF Antibodies can start to react to self - can Can develop 1-4 weeks after GABHS pharyngitis affect the heart & joints Cross-reactive antibodies produced in reaction to GABHS infection leading to fever, arthralgia, erythema marginatum, subcutaneous nodules (Osler’s nodes), increased ESR and CRP, carditis, prolonged PR interval, Sydenham’s chorea COMPLICATIONS Non-suppurative complications Poststreptococcal glomerulonephritis Can develop 1-2 weeks after infection with GABHS Injury to the glomerulus due to deposition of immune complexes and circulating autoantibodies Pediatric autoimmune neuropsychiatric disorder associated with group A streptococcal (PANDAS) infection Abrupt onset of severe exacerbations of obsessive-compulsive type behaviours or tics in children following GABHS infection Thought to be due to antibodies cross-reacting with regions in the basal ganglia → behavioural and motor disturbances COMPLICATIONS Suppurative complications Peritonsillar abscess Retropharyngeal abscess Otitis media Sinusitis Mastoiditis Cervical lymphadenitis Meningitis Bacteremia A LOOK AT THE EVIDENCE FOR DIAGNOSING STREP THROAT What are the best history questions to ask? What are the best physical exams to perform? What are the best diagnostic tests to order? Table 20–3. Likelihood Ratios for GAS Infection for Common Historical and Physical Examination Features. a The range of likelihood ratios from the studies are presented for each variable. If there was agreement among all studies, a single summary likelihood ratio is presented. Symptom LR+a LR–a Reported fever Absence of cough Absence of runny nose Presence of myalgias Presence of headache Presence of nausea Duration of symptoms < 3 days Streptococcal exposure in previous 2 weeks 0.75–2.6 1.1–1.7 0.86–1.6 1.4 1.0–1.1 0.76–3.1 0.72–3.5 1.9 0.66–0.94 0.53–0.89 0.51–1.4 0.93 0.55–1.2 0.91 0.15–2.2 0.92 Source: The Patient History, 2e Accuracy for History and Physical Examination Elements in the Diagnosis of Strep Throat Symptoms and Signs Any exudates Reported fever Measured temperature >37.8°C Anterior cervical nodes swollen/enlarged Pharyngeal exudates Tonsillar swelling/enlargement Tonsillar or pharyngeal exudates Anterior cervical nodes tender Tonsillar exudates Sensitivity (95% CI) Specificity or Range 0.21-0.58 0.69-0.92 0.3-0.92 0.23-0.90 0.11-0.84 0.43-0.96 LR+ (95% CI) or Range 1.5-2.6 0.97-2.6 1.1-3.0 LR- (95% CI) or Range 0.66-0.94 0.32-1.0 0.27-0.94 0.55-0.82 0.34-0.73 0.47-2.9 0.58-0.92 0.03-0.48 0.56-0.86 0.76-0.99 0.56-0.86 2.1 (1.4-3.1) 1.4-3.1 0.90 (0.75-1.1) 0.63 (0.56-0.72) 0.28-0.61 0.62-0.88 1.8 (1.5-2.3) 0.74 (0.66-0.82) 0.32-0.66 0.53-0.84 1.2-1.9 0.60 (0.49-0.71) 0.36 (0.21-0.52) 0.71-0.98 3.4 (1.8-6.0) 0.72 (0.60-0.88) Source: Ebell MH, Smith MA, Barry HC, Ives K, Carey M. The rational clinical examination. Does this patient have strep throat? JAMA. 2000 Dec 13;284(22):2912-8. Accuracy for History and Physical Examination Elements in the Diagnosis of Strep Throat Sensitivity (95% CI) or Range No cough 0.51-0.79 No coryza 0.42-0.84 Myalgias 0.49 (0.43-0.56) History of sore throat 0.18-0.93 Headache 0.48 (0.42-0.53) Pharynx injected 0.43-0.99 Measured 0.22-0.58 temperature >38.3°C Nausea 0.26 (0.12-0.43) Duration