Streptococcus pneumoniae infection

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Streptococcus pneumoniae infection Microchapters

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Patient Information

Overview

Classification

Community Acquired Pneumonia
Endocarditis
Sinusitis
Bronchitis
Meningitis

Cause

Laboratory Findings

Medical Therapy

Primary Prevention

This page is about clinical aspects of the disease.  For microbiologic aspects of the causative organism(s), see Streptococcus pneumoniae.

For patient information click here.

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Usama Talib, BSc, MD [2]

Overview

Streptococcus pneumoniae, or pneumococcus, is a Gram-positive, alpha-hemolytic diplococcus bacterium and a member of the genus Streptococcus.[1] A significant human pathogen, S. pneumoniae was recognized as a major cause of pneumonia in the late 19th century and is the subject of many humoral immunity studies.

Despite the name, the organism causes many types of infection other than pneumonia, including acute sinusitis, otitis media, meningitis, osteomyelitis, septic arthritis, endocarditis, peritonitis, pericarditis, cellulitis, and brain abscess.

S. pneumoniae is the most common cause of bacterial meningitis in adults and children, and is one of the top two isolates found in otitis media.[2] Pneumococcal pneumonia is more common in the very young and the very old.

S. pneumoniae can be differentiated from Streptococcus viridans, which is also alpha hemolytic, using an optochin test, as S. pneumoniae is optochin sensitive. The encapsulated, gram-positive coccoid bacteria have a distinctive morphology on gram stain, the so-called, "lancet shape." It has a polysaccharide capsule that acts as a virulence factor for the organism; 91 different capsular types are known, and these types differ in virulence, prevalence, and extent of drug resistance.

Historical Perspective

Pathophysiology

Causes

Differentiating Streptococcus pneumoniae infection from other Diseases

Epidemiology & Demographics

Risk Factors

Natural History, Complications & Prognosis

Diagnosis

History & Symptoms | Physical Examination | Lab Findings | Chest X Ray | CT | Other Imaging Findings | Other Diagnostic Studies

Treatment

  • Streptococcus pneumonia treatment
  • 1. Lung (Community-acquired pneumonia)[3]
  • 1.1 Penicillin sensitive (minimum inhibitory concentration < 2 mcg/ml)
  • Preferred regimen: Penicillin G 5-24 MU IV in equally divided doses q4-6h, Amoxicillin 1 g PO tid (+/- macrolide)
  • Alternative regimen: Macrolides (Azithromycin (IV) 500 mg IV qd for at least 2 days followed by 500 mg PO qd 7-10 days or Clarithromycin extended-release tablets 1000 mg PO qd for 7 days) and oral Cephalosporins-Cefpodoxime 200 mg PO bd, (Cefprozil 500 mg PO bd, Cefditoren 400 mg PO bd, Cefdinir 300 mg PO bd), OR parenteral Cephalosporins-Ceftriaxone 2 g IV q24h (or Cefotaxime 1-2 g IV q6-8h), Clindamycin 600-1200 mg IV/IM q6-12h, do not give single IM doses > 600 mg; IV infusion rates should not exceed 30 mg/min , Doxycycline 100 mg PO bd, respiratory flouroquniolones.
  • 2.Endocarditis[4]
  • Preferred regimen (1): Aqueous crystalline Penicillin-G 6 MU q4-6h IV for 4 weeks
  • Preferred regimen (2) (who are unable to tolerate beta lactams therapy): Vancomycin 15 mg/kg IV q12h (target trough concentration, 10-15 mcg/mL); for troughs of 15-20 mcg/mL (MIC, 1 mcg/mL or less), 15-20 mg/kg (actual body weight) IV q8-12h for most patients with normal renal function
  • Preferred regimen (3) (If the isolate is resistant (MIC 2 g/mL) to cefotaxime): Cefotaxime 1-2 g q8-12h IV/IM (max dose: 12 g/24 hr) AND Vancomycin 15 mg/kg/day IV q12h AND Rifampin 300 mg IV/PO q8h for 6 weeks, in combination with appropriate antimicrobial therapy
  • Alternative regimen (1): Cefazolin 0.5-2 g q8h IV/IM (max dose: 12 g/24 hr)
  • Alternative regimen (2): Ceftriaxone 2 g IV q12h
  • Note : Streptococcus pneumoniae with intermediate doses minimum inhibitory concentration (MIC) 0.12 g/mL–0.5 g/mL Penicillin resistance (MIC 0.1 to 1.0 g/mL) or high Penicillin resistance (MIC 2.0 g/mL) is being recovered from patients with bacteremia.
  • 3. Sinuses (sinusitis)[5]
  • Empiric therapy
  • 3.1 For initial empiric treatment of acute bacterial rhinosinusitis in adults
  • 3.2 For second-line high-dose therapy for acute bacterial rhinosinusitis in adults
  • Preferred regimen: Amoxicillin 2 g/Clavulanate 125 mg PO bid recommended by the Infectious Disease Society of America (IDSA).
  • Note: The second line high dose therapy is recommended in adults who have failed initial therapy, in regions of high endemic rates (10% or greater) of invasive Penicillin-nonsusceptible Streptococcus pneumoniae, severe infection.
  • 4. Bronchi (acute exacerbation of chronic bronchitis)[6]
  • Preferred regimen (1): Amoxicillin 875 mg PO q12h or 500 mg PO q8h
  • Preferred regimen (2): Doxycycline 100 mg PO q12h
  • 5. CNS (meningitis)[7]
  • Empiric therapy
Note: Middle ear infections (otitis media), peritoneum infections (spontaneous bacterial peritonitis), pericardium infections (purulent pericarditis), skin infections (cellulitis) and eye infections (conjunctivitis) caused by Streptococcus pneumonia.
  • Prevention
  • 1. Pneumovax (23-valent) prevents bacteremia; impact on rates of CAP are modest or nil.
  • 2. Prevnar vaccine for children <2 yrs age prevents invasive pneumococcal infection in adults by herd effect. Impact is impressive with rates of invasive pneumococcal infection down 80% in peds and 20-40% in adults.
  • 3. Risk for bacteremia in splenectomy, HIV, smokers, black race, multiple myeloma, asthma.


References

  1. Ryan KJ; Ray CG (editors) (2004). Sherris Medical Microbiology (4th ed. ed.). McGraw Hill. ISBN 0-8385-8529-9.
  2. Dagan R. "Treatment of acute otitis media - challenges in the era of antibiotic resistance". Vaccine. 19 Suppl 1: S9–S16. PMID 11163457.
  3. Mandell LA, Wunderink RG, Anzueto A, Bartlett JG, Campbell GD, Dean NC; et al. (2007). "Infectious Diseases Society of America/American Thoracic Society consensus guidelines on the management of community-acquired pneumonia in adults". Clin Infect Dis. 44 Suppl 2: S27–72. doi:10.1086/511159. PMID 17278083.
  4. Baddour LM, Wilson WR, Bayer AS, Fowler VG, Bolger AF, Levison ME; et al. (2005). "Infective endocarditis: diagnosis, antimicrobial therapy, and management of complications: a statement for healthcare professionals from the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease in the Young, and the Councils on Clinical Cardiology, Stroke, and Cardiovascular Surgery and Anesthesia, American Heart Association: endorsed by the Infectious Diseases Society of America". Circulation. 111 (23): e394–434. doi:10.1161/CIRCULATIONAHA.105.165564. PMID 15956145.
  5. Chow AW, Benninger MS, Brook I, Brozek JL, Goldstein EJ, Hicks LA; et al. (2012). "IDSA clinical practice guideline for acute bacterial rhinosinusitis in children and adults". Clin Infect Dis. 54 (8): e72–e112. doi:10.1093/cid/cir1043. PMID 22438350.
  6. Bartlett, John (2012). Johns Hopkins ABX guide : diagnosis and treatment of infectious diseases. Burlington, MA: Jones and Bartlett Learning. ISBN 978-1449625580.
  7. Tunkel AR, Hartman BJ, Kaplan SL, Kaufman BA, Roos KL, Scheld WM; et al. (2004). "Practice guidelines for the management of bacterial meningitis". Clin Infect Dis. 39 (9): 1267–84. doi:10.1086/425368. PMID 15494903.