What is invasive pneumococcal disease (Invasive Streptococcus pneumoniae infection)?

From the Guidelines

Invasive pneumococcal disease (IPD) refers to severe infections caused by the bacteria Streptococcus pneumoniae (pneumococcus) that invade normally sterile sites in the body, including the bloodstream, cerebrospinal fluid, or pleural cavity, and can lead to life-threatening conditions such as bacteremia, meningitis, and bacteremic pneumonia. This occurs when the bacteria spread beyond the respiratory tract, where they commonly reside, and can affect anyone, but is particularly concerning in vulnerable populations such as young children, older adults, and those with weakened immune systems 1.

Key Characteristics of Invasive Pneumococcal Disease

• IPD includes serious conditions like bacteremia (bacteria in the blood), meningitis (infection of the membranes covering the brain and spinal cord), and bacteremic pneumonia (lung infection with bacteria in the blood) 1.
• The bacteria spread through respiratory droplets from person to person, and while many people carry pneumococcus in their nose and throat without illness, in some cases the bacteria overcome the body's defenses and cause invasive disease 1.
• Prevention primarily relies on pneumococcal vaccines, which are recommended for high-risk groups, such as adults aged ≥65 years and those with underlying medical conditions that put them at greater risk for serious pneumococcal infection 1.

Treatment and Prevention

• Treatment typically involves antibiotics, with penicillin being common, though antibiotic resistance is an increasing concern requiring careful selection of antimicrobial therapy 1.
• The use of 13-valent pneumococcal conjugate vaccine and 23-valent pneumococcal polysaccharide vaccine among adults aged ≥65 years is recommended to prevent IPD, with updated recommendations from the Advisory Committee on Immunization Practices (ACIP) 1.

Important Considerations

• The bacteria can cause serious illness, including sepsis, meningitis, and pneumonia with bacteremia (invasive) or without bacteremia (noninvasive) 1.
• Widespread use of pneumococcal conjugate vaccines in children has led to sharp declines in pneumococcal disease among unvaccinated children and adults by preventing carriage, and thereby transmission, of vaccine-type strains 1.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Definition of Invasive Pneumococcal Disease

• Invasive pneumococcal disease (IPD) is defined as infection confirmed by the isolation of Streptococcus pneumoniae from a normally sterile site, which classically presents as bacterial pneumonia, meningitis, or primary bacteraemia 2.
• IPD can also manifest in unusual forms, such as endocarditis, arthritis, spontaneous bacterial peritonitis, and osteomyelitis, which are referred to as unusual invasive pneumococcal disease (uIPD) 2.

Clinical Presentations of IPD

• The most common clinical presentations of IPD are pneumonia, meningitis, and primary bacteraemia 3, 4.
• Bacteremic pneumonia is the most frequent clinical presentation of IPD, accounting for 66.3% of cases 5.
• Unusual manifestations of IPD, such as osteoarticular infection and gastrointestinal disease, can also occur 2.

Risk Factors and Mortality

• IPD primarily affects young children, older adults (> 65 years of age), and individuals with comorbidities or impaired immune systems 3.
• The mortality rate for IPD ranges from 10 to 30% in adults, and is much lower (< 3%) in children 3.
• The all-cause mortality rate for uIPD is 32%, which is higher than that of typical IPD 2.
• A Charlson Index >2 and a Pitt Score >2 are independent predictors of mortality in patients with IPD 2.

Vaccination and Prevention

• Vaccinating adults and high-risk patients with the pneumococcal polysaccharide vaccine can reduce the incidence of IPD in populations at risk 3.
• The introduction of pneumococcal vaccination has led to a significant decrease in the incidence and mortality of IPD in adults 5.
• Increasing vaccine coverage in adults, particularly in individuals with risk factors, is necessary to further reduce morbidity and mortality from IPD 5.