A 9 year old female child presented to the emergency room with fever, cough, and fast breathing for two days. She has a history of SLE and is on medications including hydroxychloroquine, azathioprine, and prednisone. On examination, she was lethargic, breathing rapidly, feverish, and had a weak pulse. Blood tests showed 22,000 white blood cells with neutrophilia. Blood cultures were drawn and she was started on empirical antibiotics including meropenem and vancomycin. The blood culture later grew Streptococcus pneumoniae. Based on the MIC values, ceftriaxone was chosen over vancomycin and the other antibiotics were stopped. The child's condition improved

1. 9 yr old female child presented at ER with complaints of fever, cough and fast breathing for 2 days
Known case of SLE on Hydroxychloroquine , Azathioprine and Prednisolone .
O/E : Lethargic , tachypnea , febrile feeble peripheral pulse, Temp : 104 F ,
CBC : 22,000 , Neutrophilia
Blood culture was done
Started on empirical antibiotic therapy with Meropenem and Vancomycin
Case

2. Significance of MIC values in Blood culture report
Both Ceftriaxone and vancomycin are
sensitive, which one to select?
Look at break point and MIC?
Divide Break point with MIC = Higher
value suggest more killing power of
antibiotic mathematically
Vancomycin 1/0.25 = 4
Ceftraixone 01/0.12 = 8.3

3. Blood culture grew Streptococcus pneumonia :
Ceftriaxone was started
Meropenem and Vancomycin were stopped
Vancomycin is still reserve a drug, should be used
in right clinical settings, eg meningitis
Child clinically improved .
Significance of MIC values in Blood culture report

4. Sensitive
Sensitive, but above is better
mathematically
MIC
MIC
MIC
Intermediate, higher dose of
antibiotic might suffice
Resistant