January 2024 Device-associated Module
BSI
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secondary to IAB because the patient meets IAB criterion 3b with fever, nausea, and abdominal
pain. Also, the CT scan results are definitive for an intraabdominal infection, and there is an MBI
organism identified in the blood specimen . The organism identified in the blood specimen is
used as an element to meet the Organ/Space SSI site-specific infection criterion and is collected
during the SSI surveillance period. The patient also meets IAB criterion 3a with fever, nausea,
abdominal pain, and the organism (Escherichia coli) identified from the site-specific specimen
culture. Although the organism identified (Escherichia coli), differs from the organism used to
meet IAB criterion 3b (Bacteroides fragilis), the BSI is considered secondary to the organ/space SSI
IAB and both organisms (Escherichia coli and Bacteroides fragilis) would be listed as the IAB
infection pathogens.
*Example G: Patient is febrile with a new onset of cough, and has a positive chest imaging test
indicating the presence of an infiltrate. Blood and bronchoalveolar lavage (BAL) specimens are
collected that identifies Klebsiella pneumoniae > 10
4
CFU/ml from the BAL and Pseudomonas
aeruginosa from the blood. Although the organisms in the blood specimen and site-specific
specimen do not match for at least one organism, the patient can meet PNU2 using either the
identification of an organism from blood specimen or the BAL specimen as one of the elements of
the infection criterion. The positive blood culture or BAL specimen plus the infiltrate on chest
imaging test, fever, and new onset of cough are used to fully meet the PNU2 definition. The
blood culture is considered to be a secondary BSI to PNEU and both organisms are listed as PNEU
pathogens.
*In situations where an NHSN infection definition can be met using more than one criterion of the
infection definition, it is possible that identification of an organism from the blood and site-specific
specimens may not match, and a BSI may still be considered a secondary BSI.
Reporting Guidance - When Neither Scenario 1, 2, or the NEC Exception Can Be Applied:
If the organism identified from the blood specimen does not match the organism from the site-specific
specimen, and that blood specimen cannot be used to meet the site-specific infection criteria, that blood
specimen cannot be considered a secondary BSI, and in this scenario, the positive blood specimen is
considered a primary BSI.
Example 1: Patient has pustules on their abdomen along with tenderness and swelling. Purulent
material is obtained from the pustules and is positive for Streptococcus Group B. A blood
specimen collected the same day identifies methicillin resistant Staphylococcus aureus. Because
the organisms from the pustules and blood specimens do not match, and SKIN does not include a
positive blood specimen as an element, both a site-specific infection, SKIN (criterion 1 or 2a), and
a primary BSI is reported.
Example 2: A patient has an abscess in the soft tissue around a percutaneous endoscopic
gastrostomy (PEG) tube, identified by CT scan, and there is purulent drainage noted from the site.
There is no site-specific specimen collected or other sites of infection identified, however, a blood
specimen is positive for Staphylococcus aureus. Since there are no site-specific cultures collected,
ST criterion 1 is not met which means a blood specimen cannot deemed secondary. Therefore,
the positive blood specimen must be investigated as primary BSI. The patient has an ST infection
(criterion 2), and a primary BSI with the pathogen Staphylococcus aureus.