Question

A 60-year old male is seen in an emergency room complaining of fever, chills and dizziness. His temperature is 102 degrees F. He has had periods of both constipation and diarrhea over the past several months. His vitals show that he is hypotensive and tachycardic. Blood is drawn for a CBC and culture. A stool specimen is obtained for a guaiac test.

All blood cultures were positive within 24 hours.

Gram stains reveal GPC in chains.

Gray gamma-hemolytic colonies are isolated in sub-culture.

Biochemical testing:

Catalase negative

Growth on bile esculin agar

No growth in 6.5% salt

Negative PYR test

Stool Guaiac test is positive

A) How do we determine whether or not the positive blood culutures are the result of contamination?

B) Does this patient have septicemia?

C) What is the likely identification of this organism?

D) Keeping the positive stool guaiac test in mind, what further testing may be needed to discover the underlying cause of this patient's condition?

Answer 1

a in blood cultures differentiate bacterimia and contamination , in contamination bacteria from outside source are introduced in to sample . by evaluating the signs and symptoms physician can identify whether it is symptoms of bacterimia if patient was hypotensive , tachycardiac and febrile it suggest bacterimia collect samples from 2 different sites for culture ,repeat culture .multiple positive result suggest bacterimia

b hypotension ,tachycardia are present inthe patient suggestive of septicemia other symptoms fever ,chill ,mental confusion

c enterococci also known as group d streptococci .enterococus faecalis in this genus can cause sepsis .bile solubility and optochin sensitivity are characteristic

d if the test is positive a colonoscopy done to find the cause