Intracranial complications are rare in developed countries but may include meningitis, epidural abscess, brain abscess, lateral venous sinus thrombosis, cavernous sinus thrombosis, subdural empyema, and carotid artery thrombosis. Paranasal sinusitis Sinusitis Sinusitis is inflammation of the paranasal sinuses due to viral, bacterial, or fungal infections or allergic reactions. Most commonly, the maxillary and ethmoid sinuses are affected.
Infection of the sinuses causes pain and purulent discharge and may extend into the cranium, causing the following complications:. Acute purulent meningitis Acute Bacterial Meningitis Acute bacterial meningitis is rapidly progressive bacterial infection of the meninges and subarachnoid space.
Acute bacterial endocarditis Infective Endocarditis Infective endocarditis is infection of the endocardium, usually with bacteria commonly, streptococci or staphylococci or fungi. Pneumococcal endocarditis may produce a corrosive valvular lesion, with sudden rupture or fenestration, leading to rapidly progressive heart failure requiring valve replacement. Austrian syndrome is a rare condition characterized by the triad of pneumococcal meningitis, pneumonia, and endocarditis due to S.
Native aortic valve insufficiency is the most common cause of heart failure in affected patients. Spontaneous pneumococcal peritonitis occurs most often in patients with cirrhosis and ascites, with no features to distinguish it from spontaneous bacterial peritonitis Spontaneous Bacterial Peritonitis SBP Spontaneous bacterial peritonitis SBP is infection of ascitic fluid without an apparent source.
Manifestations may include fever, malaise, and symptoms of ascites and worsening hepatic failure Pneumococci are readily identified by their typical appearance on Gram stain as lancet-shaped diplococci.
The characteristic capsule can be best detected using the Quellung test. In this test, application of antiserum followed by staining with India ink causes the capsule to appear like a halo around the organism. The capsule is also visible in smears stained with methylene blue. Culture confirms identification; antimicrobial susceptibility testing should be done.
Serotyping and genotyping of isolates can be helpful for epidemiologic reasons eg, to follow the spread of specific clones and antimicrobial resistance patterns. Differences in virulence within a serotype may be distinguished by techniques such as pulsed-field gel electrophoresis and multilocus sequence typing.
However, the negative predictive value the proportion of patients with a negative test that are actually disease free is low, so a negative urine antigen test should not be used to rule out pneumococcal disease. A beta-lactam, macrolide, respiratory fluoroquinolone eg, levofloxacin , moxifloxacin , gemifloxacin , tetracycline eg, omadacycline , or pleuromutilin eg, lefamulin.
If pneumococcal infection is suspected, initial therapy pending susceptibility studies should be determined by local resistance patterns. Although preferred treatment for pneumococcal infections is a beta-lactam or macrolide antibiotic, treatment has become more challenging because resistant strains have emerged.
Strains highly resistant to penicillin, ampicillin , and other beta-lactams are common worldwide. The most common predisposing factor to beta-lactam resistance is use of these drugs within the past several months. Resistance to macrolide antibiotics has also increased significantly; these drugs are no longer recommended as monotherapy for hospitalized patients with community-acquired pneumonia.
Intermediately resistant organisms may be treated with usual or high doses of penicillin G or another beta-lactam. Seriously ill patients with nonmeningeal infections caused by organisms that are resistant to penicillin can often be treated with ceftriaxone , cefotaxime , or ceftaroline. Fluoroquinolones eg, moxifloxacin , levofloxacin , gemifloxacin , omadacycline , and lefamulin are effective for respiratory infections with highly penicillin-resistant pneumococci in adults.
Evidence suggests that the mortality rate for bacteremic pneumococcal pneumonia is lower when combination therapy eg, macrolide plus beta-lactam is used.
All penicillin-resistant isolates have been susceptible to vancomycin so far, but parenteral vancomycin does not always produce concentrations in cerebrospinal fluid adequate for treatment of meningitis especially if corticosteroids are also being used. Therefore, in patients with meningitis, ceftriaxone or cefotaxime , rifampin , or both are commonly used with vancomycin. We also demonstrated that wild-type strains and pneumolysin mutants oxidized oxy-hemoglobin to met-hemoglobin.
Hydrogen peroxide knockout mutants, however, failed to oxidize oxy-hemoglobin. Therefore, the greenish halo formed on cultures of S. Figure 7. In a positive quellung reaction, the capsule appears as an enlarged clear halo surrounding the dark blue stained cell.
Top of Page. Skip directly to site content Skip directly to page options Skip directly to A-Z link. Section Navigation. Facebook Twitter LinkedIn Syndicate. Chapter 8: Identification and Characterization of Streptococcus pneumoniae.
Minus Related Pages. Printer friendly version pdf icon [14 pages] S. Related Links. Links with this icon indicate that you are leaving the CDC website. Like other streptococci, they lack catalase and ferment glucose to lactic acid.
Unlike other streptococci, they do not display an M protein, they hydrolyze inulin, and their cell wall composition is characteristic both in terms of their peptidoglycan and their teichoic acid. Gram Stain of a film of sputum from a case of lobar pneumonia. In all cases, growth requires a source of catalase e. On agar, pneumococci grow as glistening colonies, about 1 mm in diameter. Two serotypes, types 3 and 37, are mucoid. Pneumococci spontaneously undergo a genetically determined, phase variation from opaque to transparent colonies at a rate of 1 in 10 5.
The transparent colony type is adapted to colonization of the nasopharynx, whereas the opaque variant is suited for survival in blood.
The chemical basis for the difference in colony appearance is not known, but significant difference in surface protein expression between the two types has been shown. Streptococcus pneumoniae is a fermentative aerotolerant anaerobe. It is usually cultured in media that contain blood. On blood agar, colonies characteristically produce a zone of alpha green hemolysis, which differentiates S. Special tests such as inulin fermentation, bile solubility, and optochin an antibiotic sensitivity must be routinely employed to differentiate the pneumococcus from Streptococcus viridans.
Streptococcus pneumoniae Gram-stain of blood broth culture.
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