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INFECTIONS OF THE UPPER RESPIRATORY TRACT •They are among the most common reasons for visits to primary care Providers • the illnesses are typically mild •Even though the minority (~25%) of cases are caused by bacteria, URIs are the leading diagnoses for which antibiotics are prescribed on an outpatient basis in the United States Dr. Farzin khorvash • Although most URIs1 are caused by viruses, distinguishing patients with primary viral infection from those with primary bacterial infection is difficult • Signs and symptoms of bacterial and viral URIs are, in fact, indistinguishable • Because routine, rapid testing is neither available nor practical for most syndromes, acute infections are diagnosed largely on clinical grounds. Dr. Farzin khorvash NONSPECIFIC INFECTIONS OF THE UPPER RESPIRATORY TRACT • Nonspecific URIs, by definition, have no prominent localizing features • They are identified by a variety of descriptive names, including acute infective rhinitis, acute rhinopharyngitis/nasopharyngitis, acute coryza, and acute nasal catarrh, as well as by the inclusive label common cold. Dr. Farzin khorvash Etiology • Nearly all nonspecific URIs are caused by viruses spanning multiple virus families • For instance, rhinoviruses (~30 to 40% of cases) consist of at least 100 immunotypes • influenza virus (3 immunotypes) • parainfluenza virus (4 immunotypes) • coronavirus (at least 3 immunotypes) • adenovirus (47 immunotypes) • Respiratory syncytial virus (RSV) • enteroviruses, rubella virus, and varicella-zoster virus) Dr. Farzin khorvash Manifestations • rhinorrhea (with or without purulence) • nasal congestion • cough • sore throat • fever, malaise, sneezing, and hoarseness, are more variable • fever more common among infants and young children • myalgias and fatigue, for example, are sometimes seen with influenza and parainfluenza infections, while conjunctivitis may suggest infection with adenovirus or enterovirus • Findings on physical examination are frequently nonspecific Dr. Farzin khorvash secondary bacterial infections • • • • 0.5 and 2% of colds are complicated rhinosinusitis, otitis media, and pneumonia infants, elderly persons, and chronically ill patients prolonged course of illness, worsening of illness severity, and localization of signs and symptoms • purulent secretions from the nares or throat : sinusitis or pharyngitis • these secretions are also seen in nonspecific URI and, in the absence of other clinical features, are poor predictors of bacterial infection Dr. Farzin khorvash TREATMENT • Antibiotics have no role In the absence of clinical evidence of bacterial infection • treatment remains entirely symptom-based • decongestants • nonsteroidal anti-inflammatory drugs • dextromethorphan for cough • Clinical trials of zinc, vitamin C, echinacea, no consistent benefit for the treatment of nonspecific URI. Dr. Farzin khorvash INFECTIONS OF THE SINUS • most cases of sinusitis involve more than one sinus • the maxillary sinus is most commonly involved, the ethmoid, frontal, and sphenoid sinuses • respiratory epithelium produces mucus, is transported out by ciliary action into the nasal cavity • Normally remain sterile despite their adjacency to the bacterium-filled nasal passages • the sinus ostia are obstructed or ciliary clearance is impaired • The retained secretions may become infected with a variety of pathogens, including viruses, bacteria, and fungi. Dr. Farzin khorvash ACUTE SINUSITIS • sinusitis of <4 weeks' duration • occur primarily as a consequence of a preceding viral URI • Differentiating acute bacterial and viral sinusitis on clinical grounds is difficult • antibiotics are prescribed frequently (in 85 to 98% of all cases) Dr. Farzin khorvash Etiolog • acute obstruction of the sinus ostia or impairment of ciliary • Noninfectious causes include allergic rhinitis barotrauma or chemical irritants • nasal and sinus tumors • granulomatous diseases (e.g., Wegener's granulomatosis or rhinoscleroma) • altered mucus content (e.g., cystic fibrosis) • In the hospital setting, nasotracheal intubation Dr. Farzin khorvash organisms • viruses, bacteria, and fungi • Viral is far more common than bacterial • viruses alone and with bacteria • rhinovirus, parainfluenza virus, and influenza virus. Dr. Farzin khorvash Bacterial causes • S. pneumoniae and nontypable Haemophilus influenzae are the most common ,50 to 60% • Moraxella catarrhalis (20%) of children but less often in adults • streptococcal species and Staphylococcus aureus • Anaerobes are with infections of the roots of premolar teeth that spread into the adjacent maxillary sinuses • Chlamydia pneumoniae and Mycoplasma pneumoniae ,unclear Dr. Farzin khorvash Nosocomial cases • • • • • • S. aureus Pseudomonas aeruginosa Serratia marcescens Klebsiella pneumoniae, Enterobacter species polymicrobial ,highly resistant Dr. Farzin khorvash Fungi • immunocompromised patients • mucormycosis • occur in diabetic patients with ketoacidosis • transplant recipients • hematologic malignancies • receiving chronic glucocorticoid or deferoxamine therapy • Aspergillus and Fusarium species Dr. Farzin khorvash Manifestations • after or in conjunction with a viral URI • difficult to discriminate the clinical • bacterial sinusitis complicates only 0.2 to 2% of these viral infections. Dr. Farzin khorvash Manifestations • • • • • nasal drainage and congestion facial pain or pressure headache. Thick, purulent or discolored nasal discharge is often thought to indicate bacterial sinusitis, but it also occurs early in viral infections such as the common cold • Other nonspecific symptoms include cough, sneezing, and fever • Tooth pain, most often involving the upper molars, is associated with bacterial sinusitis Dr. Farzin khorvash Manifestations • sinus pain or pressure often localizes and be worse when the patient bends over or is supine • symptoms of advanced sphenoid or ethmoid sinus: severe frontal or retroorbital pain radiating to the occiput, thrombosis of the cavernous sinus, and signs of orbital cellulitis • advanced frontal sinusitis ,Pott's puffy tumor, swelling and pitting edema over the frontal bone ,subperiosteal abscess Dr. Farzin khorvash Life-threatening complications • Meningitis • epidural abscess • cerebral abscess. Dr. Farzin khorvash Diagnosis • illness duration • acute bacterial sinusitis is uncommon in patients whose symptoms have lasted <7 days • facial or tooth pain in combination with purulent nasal discharge that have persisted for >7 days Dr. Farzin khorvash computed tomography, sinus radiography • patients who meet these criteria, only 40 to 50% have true bacterial sinusitis • CT or XR is not recommended for routine cases, particularly early in the course of illness (i.e., at <7 days) • persistent, recurrent, or chronic sinusitis, CT of the sinuses is choice. Dr. Farzin khorvash Diagnosis • illness duration • acute bacterial sinusitis is uncommon in patients whose symptoms have lasted <7 days • facial or tooth pain in combination with purulent nasal discharge that have persisted for >7 days Dr. Farzin khorvash Diagnosis • evidence of fungal hyphal elements and tissue invasion • acute nosocomial sinusitis should be confirmed by a sinus CT scan • sinus aspirate , if possible, for culture and susceptibility testing. Dr. Farzin khorvash TREATMENT • Most patients ,improve without antibiotic therapy • mild to moderate symptoms of <7 days' duration • facilitating sinus drainage, such as oral and topical decongestants, nasal saline lavage • in patients with a history of chronic sinusitis or allergies — nasal glucocorticoids. Dr. Farzin khorvash antibiotics • do not improve after 7 days • more severe symptoms (regardless of duration) Dr. Farzin khorvash antibiotics • Empirical therapy ,S. pneumoniae and H. influenzae • amoxicillin • drug-resistant S. pneumoniae • Up to 10% of patients do not respond to initial antimicrobial therapy • these patients should be considered for sinus aspiration and/or lavage • prophylactic antibiotics to prevent episodes of recurrent acute bacterial sinusitis is not recommended. Dr. Farzin khorvash Surgical intervention and intravenous antibiotics • severe disease • intracranial complications, such as abscess or orbital involvement • acute invasive fungal sinusitis usually require extensive surgical debridement • Intravenous antifungal such as amphotericin B Dr. Farzin khorvash Treatment of nosocomial sinusitis • broad-spectrum antibiotics to cover common pathogens such as S. aureus and gram-negative bacilli • Therapy should then be tailored to the results of culture and susceptibility testing of sinus aspirates. Dr. Farzin khorvash CHRONIC SINUSITIS • symptoms of sinus inflammation lasting >12 weeks • bacteria or fungi • clinical cure in most cases is very difficult • Many patients have undergone repeated courses of antibacterial agents and multiple sinus surgeries • increasing their risk of colonization with antibiotic-resistant pathogens and of surgical complications Dr. Farzin khorvash chronic bacterial sinusitis • impairment of mucociliary clearance from repeated infections rather than to persistent bacterial infection • pathogenesis of this condition is poorly understood • certain conditions (e.g., cystic fibrosis) • most patients do not have obvious underlying conditions that result in the obstruction of sinus drainage, the impairment of ciliary action, or immune dysfunction Dr. Farzin khorvash chronic bacterial sinusitis • nasal congestion and sinus pressure, with intermittent periods for years • CT scan be helpful in defining the extent of disease and the response to therapy • endoscopic examinations and obtain tissue samples for histologic examination and culture. Dr. Farzin khorvash Chronic fungal sinusitis • immunocompetent hosts • usually noninvasive, although slowly progressive • Aspergillus species Dr. Farzin khorvash Chronic fungal sinusitis • In mild, indolent disease • repeated failures of antibacterial therapy • only nonspecific mucosal changes may be seen on sinus CT • Endoscopic surgery is usually curative in these patients, with no need for antifungal therapy Dr. Farzin khorvash Chronic fungal sinusitis • mycetoma (fungus ball) within the sinus • Treatment for this condition is also surgical • systemic antifungal therapy may be warranted in the rare case where bony erosion occurs. Dr. Farzin khorvash Chronic fungal sinusitis • allergic fungal sinusitis • history of nasal polyposis and asthma • thick, eosinophilic mucus with the consistency of peanut butter that contains sparse fungal hyphae on histologic examination. • Patients often present with pansinusitis. Dr. Farzin khorvash TREATMENT • administration of intranasal glucocorticoids; and mechanical irrigation of the sinus with sterile saline solution • When this management approach fails, sinus surgery may be indicated Dr. Farzin khorvash INFECTIONS OF THE EAR AND MASTOID • middle and external ear,skin, cartilage, periosteum, ear canal, and tympanic and mastoid cavities • Both viruses and bacteria Dr. Farzin khorvash Acute Otitis Media • when pathogens from the nasopharynx are introduced into the inflammatory fluid collected in the middle ear — e.g., by nose blowing during a URI • The diagnosis of acute otitis media requires the demonstration of fluid in the middle ear (with tympanic membrane immobility) and the accompanying signs Dr. Farzin khorvash ETIOLOGY • typically ,viral URI • RSV, influenza virus, rhinovirus, and enterovirus • they predispose the patient to bacterial • S. pneumoniae ,35% of cases • H. influenzae (nontypable strains) and M. catarrhalis are • Viruses,either alone or with bacteria in 17 to 40% of cases. Dr. Farzin khorvash MANIFESTATIONS • Fluid in the middle ear ,pneumatic otoscopy • this movement is dampened when fluid is present • the tympanic membrane can also be erythematous, bulging, or retracted • occasionally can spontaneously perforate. Dr. Farzin khorvash MANIFESTATIONS • otalgia, otorrhea, diminished hearing, fever, or irritability • Erythema of the tympanic membrane is often evident but is nonspecific • Other signs and symptoms include vertigo, nystagmus, and tinnitus. Dr. Farzin khorvash TREATMENT • most cases resolve clinically 1 week after the onset of illness • initial observation and aggressive pain management with anti-inflammatory therapy • reserving antibiotics for high-risk patients, patients with complicated disease, or patients who do not improve after 48 to 72 h. • recommend antibiotic therapy for children <2 years old and immunocompromised Dr. Farzin khorvash TREATMENT • therapy is generally empirical • except :tympanocentesis is warranted ,newborns, refractory to therapy, severely ill immune deficiency • amoxicillin is as successful as any other agent, and it remains the drug of first choice Dr. Farzin khorvash TREATMENT • 5 to 7 days for uncomplicated longer • courses ( 10 days) should be reserved for complicated cases or for children <2 years old Dr. Farzin khorvash TREATMENT • A switch in regimen • there is no clinical improvement by the third day of therapy • infection with a ß-lactamase-producing strain of H. influenzae or M. catarrhalis or with a strain of penicillin-resistant S. pneumoniae • Decongestants and antihistamines are frequently used • but clinical trials have yielded no significant evidence of benefit Dr. Farzin khorvash Recurrent Acute Otitis Media • more than three episodes within 6 months • or four episodes within 12 months • relapse or reinfection • the recommended treatment consists of antibiotics active against ß-lactamaseproducing organisms Dr. Farzin khorvash Antibiotic prophylaxis • TMP-SMX or amoxicillin can reduce • benefit is small compared with the cost of the drug and the high likelihood of colonization with antibiotic-resistant pathogens • Other approaches : • placement of tympanostomy tubes, adenoidectomy, and tonsillectomy plus adenoidectomy, are of questionable overall value, given the relatively small benefit compared with the potential for complications. Dr. Farzin khorvash Serous Otitis Media • when fluid is present in the middle ear for an extended period and in the absence of signs and symptoms of infection • In general, acute effusions are self-limited; most resolve in 2 to 4 weeks • In some cases, in particular after an episode of acute otitis media, effusions can persist for months • often associated with a significant hearing loss Dr. Farzin khorvash TREATMENT • The great majority resolve spontaneously within 3 months • Antibiotic therapy or myringotomy with insertion of tympanostomy tubes is typically reserved for • patients in whom bilateral effusion : • (1) has persisted for at least 3 months and • (2) is associated with significant bilateral hearing loss Dr. Farzin khorvash Chronic Otitis Media • persistent or recurrent purulent otorrhea , tympanic membrane perforation • some degree of conductive hearing loss • divided into two subcategories: active and inactive • Inactive disease is characterized by a central perforation of the tympanic membrane, which allows drainage of purulent fluid Dr. Farzin khorvash active • When the perforation is more peripheral, squamous epithelium from the auditory canal may invade the middle ear through the perforation, forming a mass of cholesteatoma • This mass can enlarge ,erode bone and promote further infection, which can lead to meningitis, brain abscess, or paralysis of cranialnerve VII Dr. Farzin khorvash Treatment of chronic active • is surgical; mastoidectomy, myringoplasty, and tympanoplasty • overall success rate of ~80% • Chronic inactive ;is more difficult to cure, • repeated courses of topical antibiotic drops during periods of drainage • Systemic antibiotics may offer better cure rates, but their role remains unclear. Dr. Farzin khorvash Mastoiditis • In typical acute mastoiditis, purulent exudate collects in the mastoid air cells, producing pressure that may result in erosion of the surrounding bone and the formation of abscess-like cavities that are usually evident on CT • Patients typically present with pain, erythema, and swelling of the mastoid process along with displacement of the pinna, usually in conjunction with the typical signs and symptoms of acute middle-ear infection • Rarely, patients can develop severe complications if the infection tracks under the periosteum of the temporal bone to cause a subperiosteal abscess, erodes through the mastoid tip to cause a deep neck abscess, or extends posteriorly to cause septic thrombosis of the lateral sinus. Dr. Farzin khorvash Treatment • Cultures of purulent fluid should be performed • Initial empirical therapy :against organisms associated with acute otitis media, • severe or prolonged courses : S. aureus and gram-negative bacilli (including Pseudomonas) • Most patients can be treated conservatively with intravenous antibiotics • surgery (cortical mastoidectomy) can be reserved for complicated cases and those in which conservative treatment has failed. Dr. Farzin khorvash ACUTE PHARYNGITIS • Millions of visits • the majority by typical respiratory viruses • important is with group A ß-hemolytic Streptococcus (S. pyogenes), which can progress to acute rheumatic fever and acute glomerulonephritis • the risk for both of which can be reduced by timely penicillin therapy. Dr. Farzin khorvash Etiology • 30% have no identified cause. • Respiratory viruses :rhinoviruses ,coronaviruses Influenza virus, parainfluenza virus, and adenovirus the latter as part of the more clinically severe syndrome of pharyngoconjunctival fever • HSV types 1 and 2, coxsackievirus A, CMV, EBV • Acute HIV infection Dr. Farzin khorvash Acute bacterial pharyngitis • • • • • • • • • • S. pyogenes, (~5 to 15% of all cases ) children 5 to 15 years of age Streptococci of groups C and G account Neisseria gonorrhoeae Corynebacterium diphtheriae Corynebacterium ulcerans Yersinia enterocolitica Treponema pallidum (in secondary syphilis) M. pneumoniae C. pneumoniae Dr. Farzin khorvash Anaerobic bacteria • Vincent's angina • can contribute to more serious polymicrobial infections • peritonsillar or retropharyngeal abscess Dr. Farzin khorvash Manifestations • viruses :not severe and is typically associated with a constellation of coryzal symptoms • Findings on physical examination are uncommon; • fever is rare, • tender cervical adenopathy and pharyngeal exudates are not seen. Dr. Farzin khorvash Manifestations • influenza virus can be severe with fever as well as with myalgias, headache, and cough • pharyngoconjunctival fever due to adenovirus infection is similar • Since pharyngeal exudate may be present on examination • adenoviral pharyngitis is distinguished by the presence of conjunctivitis in one-third to onehalf of patients. Dr. Farzin khorvash Manifestations • primary HSV :mimic streptococcal pharyngitis in some cases, with pharyngeal inflammation and exudate • vesicles and shallow ulcers on the palate • coxsackievirus ( herpangina):small vesicles that develop on the soft palate and uvula and then rupture to form shallow white ulcers Dr. Farzin khorvash infectious mononucleosis • Acute exudative pharyngitis coupled with fever, fatigue, generalized lymphadenopathy, splenomegaly • CMV,EBV Dr. Farzin khorvash HIV • • • • • • fever acute pharyngitis myalgias, arthralgias, malaise nonpruritic maculopapular rash lymphadenopathy mucosal ulcerations without exudate. Dr. Farzin khorvash streptococci A, C, and G • ranging from a relatively mild illness without many accompanying symptoms to clinically severe cases • pharyngeal pain, fever, chills, and abdominal pain • A hyperemic pharyngeal membrane with tonsillar hypertrophy and exudate is usually seen • tender anterior cervical adenopathy • Coryzal manifestations, including cough, are typically absent Dr. Farzin khorvash scarlet fever • Strains of S. pyogenes that generate erythrogenic toxin • characterized by an erythematous rash and strawberry tongue Dr. Farzin khorvash Diagnosis • Throat swab culture • Rapid antigen-detection tests offer good specificity (>90%) but lower sensitivity that varies across the clinical spectrum of disease (65 to 90%) Dr. Farzin khorvash RADT • all negative rapid antigen-detection tests in children be confirmed by a throat culture • do not recommend backup culture when adults have a negative rapid antigen-detection test Dr. Farzin khorvash Diagnosis • Cultures and rapid diagnostic tests for influenza virus, adenovirus, HSV, EBV9, CMV, and M. pneumoniae, are available • the monospot test for EBV • HIV RNA or antigen (p24) when acute primary HIV infection • cultures : N. gonorrhoeae, C. diphtheriae, or Y. enterocolitica Dr. Farzin khorvash TREATMENT • Antibiotic benefit:S. pyogenes • a decrease in the risk of rheumatic fever • rheumatic fever is now a rare disease, even in untreated patients • When therapy is started within 48 h of illness onset, however, symptom duration is also decreased. • reduce the spread of streptococcal pharyngitis, overcrowding or close contact Dr. Farzin khorvash streptococcal pharyngitis • single dose of intramuscular benzathine penicillin • 10-day course of oral penicillin • Erythromycin :penicillin • Testing for cure is unnecessary and may reveal only chronic colonization. • Penicillin prophylaxis (benzathine penicillin G, 1.2 million units intramuscularly every 3 to 4 weeks) for patients at risk of recurrent rheumatic fever Dr. Farzin khorvash influenza virus • amantadine, rimantadine, and the two newer agents oseltamivir and zanamivir • All of these agents need to be started within 36 to 48 h of symptom onset to reduce illness duration meaningfully • Of these agents, only oseltamivir and zanamivir are active against both influenza A and influenza B Dr. Farzin khorvash Complications • rheumatic feveracute • glomerulonephritis • numerous suppurative conditions, such as peritonsillar abscess ,otitis media, mastoiditis, sinusitis, bacteremia, and pneumonia • Therapy of acute streptococcal pharyngitis can prevent the development of rheumatic fever • no evidence that it can prevent acute glomerulonephritis Dr. Farzin khorvash peritonsillar abscess • • • • severe pharyngeal pain dysphagia, fever, medial displacement of the tonsil therapy :Oral penicillin ,with clindamycin as an alternative • Early use of antibiotics in these cases has substantially reduced the need for surgical drainage Dr. Farzin khorvash Vincent's angina • acute necrotizing ulcerative gingivitis • painful, inflamed gingiva • ulcerations of the interdental papillae that bleed easily • halitosis ,fever, malaise, and lymphadenopathy • oral anaerobes • Treatment :debridement and oral penicillin + metronidazole • clindamycin alone as an alternative. Dr. Farzin khorvash Ludwig's angina • is a rapidly progressive, potentially fulminant cellulitis involving the sublingual and submandibular spaces • typically originates from an infected or recently extracted tooth, most commonly the lower second and third molars • dysphagia, odynophagia, and "woody" edema in the sublingual region, forcing the tongue up and back with the potential for airway obstruction. • Fever, dysarthria, and drooling , speak in a "hot potato" voice Dr. Farzin khorvash treatment • Intubation or tracheostomy may be necessary to secure the airway • asphyxiation is the most common cause of death • monitored closely and intravenous antibiotics directed against streptococci and oral anaerobes • ampicillin/sulbactam • high-dose penicillin plus metronidazole. Dr. Farzin khorvash Postanginal septicemia (Lemierre's disease) • oropharyngeal infection by Fusobacterium necrophorum • starts as a sore throat (most commonly in adolescents and young adults), exudative tonsillitis or peritonsillar abscess Dr. Farzin khorvash • Infection of the deep pharyngeal tissue allows organisms to drain into the lateral pharyngeal space • which contains the carotid artery and internal jugular vein • Septic thrombophlebitis of the internal jugular vein: pain, dysphagia, and neck swelling and stiffness Dr. Farzin khorvash • Sepsis occurs 3 to 10 days after the onset • metastatic infection to the lung and other distant sites • extend along the carotid sheath and into the posterior mediastinum • mediastinitis, erode into the carotid artery, with the early sign of repeated small bleeds into the mouth • The mortality rate as 50% • Treatment : intravenous antibiotics (penicillin G or clindamycin) and surgical drainage • The concomitant use of anticoagulants to prevent embolization remains controversial but is often advised. Dr. Farzin khorvash LARYNGITIS • inflammatory process involving the larynx • are acute • by the same viruses responsible for many other URI Dr. Farzin khorvash Etiology • rhinovirus, influenza virus, parainfluenza virus, adenovirus, coxsackievirus, coronavirus, and RSV • acute bacterial respiratory infections, such as group A Streptococcus or C. diphtheriae ,M. catarrhalis Dr. Farzin khorvash Chronic laryngitis • Mycobacterium tuberculosis • Histoplasma and Blastomyces may cause laryngitis • Candida species :thrush or esophagitis and particularly in immunosuppressed patients • to Coccidioides and Cryptococcus. Dr. Farzin khorvash Manifestations • hoarseness • other symptoms and signs of URI, including rhinorrhea, nasal congestion, cough, and sore throat • Direct laryngoscopy :diffuse laryngeal erythema and edema, along with vascular engorgement of the vocal folds • tuberculous laryngitis, mucosal nodules and ulcerations visible on laryngoscopy • these lesions are sometimes mistaken for laryngeal cancer Dr. Farzin khorvash TREATMENT • humidification • voice rest • Antibiotics are not recommended except when group A Streptococcus is cultured • chronic laryngitis usually requires biopsy with culture. • Patients with laryngeal tuberculosis are highly contagious Dr. Farzin khorvash CROUP • viral respiratory illnesses • characterized by marked swelling of the subglottic region of the larynx • Croup primarily affects children <6 years old Dr. Farzin khorvash EPIGLOTTITIS • Acute epiglottitis :acute, rapidly progressive cellulitis of the epiglottis and adjacent • airway obstruction in both children and adults • Before the widespread use of H. influenzae type b (Hib) vaccine, this entity was much more common among children, with a peak incidence at ~3.5 years of age • a medical emergency, particularly in children, and prompt diagnosis and airway protection are of utmost importance. Dr. Farzin khorvash Etiology • • • • • • Hib12 group A Streptococcus S. pneumoniae Haemophilus parainfluenzae S. aureus Viruses have not yet been established as a cause of acute epiglottitis. Dr. Farzin khorvash Manifestations • more acutely in young children than in adolescents or adults • On presentation, most children have had symptoms for <24 h, including high fever, severe sore throat, tachycardia, systemic toxicity, and drooling while sitting forward • Symptoms and signs of respiratory obstruction may also be present and may progress rapidly Dr. Farzin khorvash Physical examination • moderate or severe respiratory distress • inspiratory stridor and retractions of the chest wall • These findings diminish as the disease progresses and the patient tires Dr. Farzin khorvash diagnosis • often made on clinical grounds • direct fiberoptic laryngoscopy is frequently performed in a controlled environment :"cherry-red" epiglottis and to facilitate placement of an endotracheal tube • Direct visualization in an examination room (e.g., with a tongue blade and indirect laryngoscopy) is not recommended Dr. Farzin khorvash • Lateral neck radiographs and laboratory tests • but may delay the critical securing of the airway • Neck radiographs :enlarged edematous epiglottis (the "thumbprint sign"), usually with a dilated hypopharynx and normal subglottic structures. • Laboratory tests :mild to moderate leukocytosis with a predominance of neutrophils • Blood cultures are positive in a significant proportion of cases. Dr. Farzin khorvash TREATMENT • Security of the airway • blood and epiglottis specimens have been obtained for culture • intravenous antibiotics, particularly H. influenzae • Because rates of ampicillin resistance in this organism have risen • therapy : a ß-lactam/ß-lactamase inhibitor combination or a second- or third-generation cephalosporin Dr. Farzin khorvash • ampicillin/sulbactam, cefuroxime, cefotaxime, or ceftriaxone • clindamycin and TMP-SMX reserved for patients allergic to ß-lactams • continued for 7 to 10 days • household contacts of a patient with H. influenzae epiglottitis include an unvaccinated child under the age of 4, all members of the household (including the patient) should receive prophylactic rifampin for 4 days to eradicate H. influenzae carriage. Dr. Farzin khorvash retropharyngeal abscess • sore throat, fever, dysphagia, and neck pain and are often drooling , pain with swallowing • tender cervical adenopathy, neck swelling, and diffuse erythema and edema of the posterior pharynx , bulge in the posterior pharyngeal wall • A soft tissue mass :by lateral neck radiography or CT • Because of the risk of airway obstruction, treatment begins with securing of the airway • combination of surgical drainage and intravenousantibiotic administration Dr. Farzin khorvash retropharyngeal abscess • streptococci, oral anaerobes, and S. aureus • ampicillin/sulbactam, clindamycin alone, or clindamycin plus ceftriaxone • Complications :rupture into the posterior pharynx, which may lead to aspiration pneumonia and empyema • Extension may also occur to the lateral pharyngeal space and mediastinum: mediastinitis and pericarditis • or into nearby major blood vessels Dr. Farzin khorvash