Respiratory Illness (pharyngitis/pneumonia)

- an infection of the oropharynx.

Complications

• otitis media and sinusitis
• epiglottitis
• peritonsillar abscess
• acute rheumatic fever, glomerulo-nephritis, and scarlet fever
• diptheria.

• Viruses cause most cases; how-ever, bacteria may be involved in 25% of cases or more in epidemic situations.

• In children, viruses are the main cause.

• In adults, parainfluenza and influenza, adenovirus, entero-virus, Epstein-Barr, and herpes simples also must be considered.

• S. pyogenes infections occur most frequently in school-aged children.

• Adenovirus is the most common cause in crowded living conditions (schools and military settings), as well as S. pyogenes in winter months.

Symptoms

• Sore throat, the hallmark symp-tom, usually develops acutely.

• General malaise, myalgia, fever, and upper respiratory tract symp-toms, including coryza, cough, and laryngitis may occur.

• Exudative pharyngitis is not a specific finding for strep pharyn-gitis; it also can be seen with EBV, adenovirus, herpes simplex virus, and other viral infections.

• Tender cervical lymphadenopathy with an exudative pharyngitis and leukocytosis (WBD >15,000/mm3) suggests strep infection.

• Bright erythematous rash with "sandpaper feel" involving trunk, face, and skin folds (Pastia's lines) also suggests strep infec-tion. The rash spares the palms and soles, and desquamates in the resolving phase.

• Peritonsillar abscess occurs most commonly in adults in the second and third decades of life; the su-perior pole of the tonsil is the most common location: Trismus: displaced uvula.

• Adherent gray-black membrane suggests diptheria.

• Dysphagia out of proportion to the signs of pharyngitis.

• Patient appears anxious, leaning forward, drooling.

• Examine only if prepared to do emergency endotracheal intuba-tion or tracheostomy.

• Rapid strep antigen - takes 10 minutes with sensitivity 75% to 90% and specificity over 95%.

• Throat culture including culture for N. gonorrhoeae if clinical setting dictates.

• If severe pharyngitis, use rapid strep and treat if positive. If negative, get throat culture for strep.

• Consider other diagnostic tests; i.e., Monospot, diptheria culture, N. gonorrhoeae culture. If clini-cal suspicion is very high (fever, exudate, headache, adenopathy), treat with no culture.

Definition

Bacterial, viral, and occasionally fungal infections of the paranasal sinuses may cause acute or chornic sinusitis. Acute sinusitis is most commonly caused by H. influenzae or S. pneumoniae. It is often difficult to distinguish infectious sinusitis from noninfectious allergic conditions.

Maxillary Sinusitis

• Extremely common (1% of viral upper respiratory infections are complicated by acute maxillary sinusitis).

• Complications related to maxil-lary sinusitis are rare.

• Associated with facial pain, puru-lent nasal discharge, and altered facial sensation. Facial pain ag-gravated by stooping.

• Transillumination of the sinuses.

• Unusual, but may be complicated by potentially life-threatening infections:
• cranial osteomyelitis
• brain abscess
• frontal subperiosteal absceess
• epidural abscess or subdural abscess

• Pain and tenderness over the frontal sinus.

• Fever, purulent nasal discharge, and signs of involvement of the maxillary sinuses may be seen.

• Pitting edema over the forehead suggests a possible diagnosis of a subperiosteal abscess.

• Bacterial infections common cause of orbital cellulitis: tender-ness of the eye, ophthalmoplegia, chemosis, proptosis, and erythema of the lids.

• Rare, but the relationship of the sphenoid sinus to the pituitary gland, optic canals, dura mater, and cavernous sinus may lead to severe complications.

• Headache is the most common initial symptom. Pain is often unilateral and may involve the frontal, temporal, or occipital regions. Patients may have unex-plained tenderness over the vertex of the skull or over the mastoid.

• Fever is frequently present with acute infection, but may be absent with chronic infection.

• Associated infections: Most cases follow viral upper respiratory tract infection. Symptoms of viral infection that persist longer than 7 days should raise the question of sinusitis.

• Mechanical problems: Deviated nasal septum, facial trauma, nasal polyps.

• Allergies: Allergic rhinosinusitis predisposes.

• Extension of odontogenic infec-tions.

• Cystic fibrosis.

• Immunosuppressed patients:
• rhinocerebral mucormycosis - DKA
• invasive aspergillosis - neutropenia.

• AIDS - extremely common.

• Nosocomial sinusitis: Prolonged nasotracheal or nasogastric intubation associated with fever.

• Radiologic exam is the most sen-sitive and specific test.

• Water's view is the best exam of the maxillary sinuses.
• Findings of opacity, air/fluid level, or mucosal thickening greater than 8 mm correlate with purulent sinusitis.

• X-ray exam may be helpful in diagnosing frontal, ethmoid, and sphenoid sinusitis.

• CT scan, when indicated, is even more sensitive in detecting sinusitis.

• Direct sinus aspiration is the only procedure that can provide accu-rate information concerning etiol-ogy.

- an inflammatory process invol-ving the lung parenchyma.

• Except in immunocompromised patients, an infiltrate must be present on a chest film to make the diagnosis.

• Community acquired refers to any pneumonia contracted outside the hospital.

• Aspiration pneumonia refers to the aspiration of large quantities of oropharyngeal contents, pri-marily in patients with altered consciousness or impaired swal-lowing.

• Nosocomial pneumonia is one that is acquired in a hospital set-ting.

• Estimated incidence: 1.5 cases per 100 persons per year.

• Overall mortality for all age groups is 24 per 100,000; much higher for patients over age 65; fatality rate for elderly is 12%.

• Pneumonia is the most common cause of infection-related death.

• Aspiration of oropharyngeal or nasopharyngeal microbes (e.g., pneumococcus).

• Inhalation of airborne microbes (e.g., Legionella).

• Hematogenous spread from distant sites of infection (S. Aureus in IV drug users).

• Common symptoms: Cough, fever, dyspnea, chest pain.

• Cough may not be present in the elderly or immunocompromised.

• Bacterial: Productive, purulent, rust-colored or bloody sputum often classical presentation excepting Legionella, TWAR, and mycoplasma.

• Viral: May be nonproductive. Often atypical presentation.
• M. pneumoniae, Pneumocystis carinii, Legionella nonproductive.
• chest pain - pleuretic.

• Fever.

• Tachycardia.

• Tachypnea, cyanosis.

• Examination of the chest:
• early decreased breath sounds, later rales as pneumonia pro-gresses
• evidence of consolidation sug-gests bacterial process
• few if any findings for flu, Mycoplasma, Chlamydia, despite impressive findings on chest film

• Splenectomy scar suggests possi-ble infection with encapsulated organisms.

• Mental status changes suggest hy-poxia and/or concurrent meningi-tis.

• WBC count
• usually elevated in bacterial
• may be normal in viral and atypical pneumonias

• sputum
• appearance:

- color
- amount
- consistency
- odor
• microscopic evaluation

- Gram's stain: adequate sam-ple should have >25 neutro-phils and <10 epithelial cells per low power field (100X)
- presence of WBCs without bacteria suggests Mycoplasma, Legionella, or virus
- Gomori's methenamine silver stain for P. carinii
- acid-fast stain for TB
- fungal stains.

• cultures

• serologic studies.

• Lobar consolidation - pneumococcus.

• Bilateral diffuse infiltrates - P. carinii or viral etiology.

• M. tuberculosis and Klebsiella pneumoniae - upper lobe involvement.

• Superior or basilar segments of lower lobes or posterior segments of upper lobes suggest aspiration.

• Cavitation - TB, S. aureus, or gram negative bacilli.

• Perihilar distribution - early mycoplasma or influenza.

Streptococcus pneumoniae
Haemophilus influenzae
Staphylococcus aureus
Mycoplasma pneumoniae
Legionella pneumophila

Streptococcus pneumoniae

• Most common cause of commun-ity-acquired pneumonia.

• Abrupt onset with a single shak-ing chill (80% of cases).

• Patients appear ill and are usually febrile, frequently to 40 degrees C; tachycardia and tachypnea are present.

• Pleural effusions (20% of cases).

• Leukocytosis is typical.

• Lobar or sublobar consolidation on chest film.

• Gram's stain 85% sentivity and specificity.

• Gram's stain (>10 lancet-shaped diplococci POIF) 85% specific.

• Blood culture 25% sensitive and 100% specific.

• Fever, chilld, cough, and dyspnea are the most common complaints.

• Minimal temp, pulse, and RR ele-vations; rales may be present.

• Gram's stain shows numerous polymorphonuclear leukocytes amid small pleomorphic gram-negative coccobacilli.

• Bacteremia occurs in 33% of cases.

• Bronchopneumonia most common pattern; lobar colsolidation can occur.

• Most common cause of commun-ity-acquired pneumonia in young adults with no underlying risk factors.

• Infections increase in frequency in fall and early winter.

• Insidious onset 60%; patients don't appear ill; rashes may be seen.

• Extrapulmonary manifestations:
• cold agglutinins (33% to 72%)
• autoimmune hemolytic anemia (24%)
• meningitis and meningoence-phalitis (4%)
• Myopericarditis (4%)

• WBC 10,000 or less in 75% of cases.

• Gram's stain reveals PMNs with no predominant organism.

• Comp fix titers of 1:64 on acute sera is presumptive evidence of infection.

• Chest film findings vary:
• patchy bronchopneumonia (40%) - insidious onset and nonspecific symptoms
• lobar or segmental consolida-tion (40%) - acute onset sug-gestive of bacterial
• interstitial (20%) - longer du-ration of symptoms with less fever and more dyspnea
• pleural effusions may be seen in up to 20% of patients.

• Common in immunocompromised hosts and in healthy adults as a complication of flu.

• Abrupt onset, multiple chills, productive cough, pleuritic chest pain.

• Patients appear toxic, tachycardia, temp >40C.

• In hematogenous form, endocardi-tis should be considered.

• WBC usually above 15,000.

• Gram's stain with large gram-positive cocci in clusters and PMNs.

• On chest film, bilateral lower lobe bronchopneumonia is characteristic.

• Abscess, empyema, and pleural effusions are common complica-tions.

• Organism may spread via drinking water, and infection occurs from inhalation of aerosols.

• Presentation may be insidious or abrupt - anorexia, weakness, malaise in 100%.

• Cough may be dry initially, but later become productive or bloody.

• Nonremitting temp elevation >39øC in 80%.

• Tachypnea, rales, and evidence of consolidation are present.

• WBC >10,000 or greater is typical.

• Alkaline phosphatase, bilirubin, and transaminase often elevated.

• Hyponatremia and hypophospha-temia are common.

• Gram's stain - few to mod PMNs and rarely faintly staining gm negative rods.

• Chest film initially - patchy al-veolar infiltrate in single lobe (lo-wer lobes commonly).

• Most common viral cause; peak incidence in winter.

• Near end of typical flu illness (i.e., fever, headache, sore throat, myalgia, malaise), the patient suddenly worsens. Cough is scant watery, progressing to mucoid or bloody.

• Pleuritic chest pain present in 50% of patients.

• Chest exam reveals rales.

• WBC from normal to 15,000.

• Gram's stain - few PMNs with-out predominant organism.

• Virus isolation - nasopharyngeal swabs, sputum, throat washings, transtracheal aspirate, or lung biopsy. Culture requires 7 days and is only 60% sensitive.

• Chest film - perihilar infiltrates.

Recommended Diagnostic Approach

• Obtain history and physical.

• Get a CBC (the absence of ele-vated WBC does not rule out pneumonia).

• Get a good quality sputum for Gram stain andculture.

• Chest film (infiltrate must be present to diagnose pneumonia), except in severe IVVD or immu-nocompromised patients.

• Blood cultures (when indicated).

• ABG (when indicated).

In 1990, 2.9 million deaths world-wide were TB-related, with 20,000,000 active cases. The incidence in the U.S. has been increasing over recent years:

1953 53/100,000
1984 9.4/100,000
1990 10.5/100,000

Screening Modalities

Screening modalities include the mantoux skin test (PPD), with results read 48 to 72 hours later; chest x-ray; and sputum smear studies.

Finding active disease requires a constant level of suspicion. Clinical clues include prior TB exposure, night sweats, weight loss, and prolonged respiratory symptoms. If in doubt, mask the patient and then proceed with your evaluation.

Chest X-ray findings particularly suspicious for TB include cavitary lesions, upper lobar infiltrates, miliary patterns, and pleural involvement.

Treatment

The advent of multi-drug resistant TB has made treatment much more complex, but treatment of active disease has always been multi-drug because resistance to single agent therapy develops rapidly.

RSV is the most important respiratory tract pathogen in early childhood. It also occurs in adults. It is the most common cause of bronchio-litis and pneumonia in children under one year of age.

Rapid antibody kits for RSV, similar to the rapid strep test, are available. An antiviral agent, Ribavirin, is available to treat severe cases.