Question

Cecil is admitted to the hospital with severe chest pain and diagnosed with an acute MI. He is put in the CCU where invasive monitoring allows him to survive the episode. On the 13th day Cecil develops a significant fever. A central venous catheter is removed, and blood cultures taken. Both aerobic and anaerobic blood cultures show catalase positive, coagulase positive cocci in clusters.

Answer 1

The gram positive staphylococcus aureus bacteria show clusters or clumps on coagulated plasma drop. Staph. aureus produces coagulase enzyme that converts the fibrinogen in plasma to fibrin forming clumps.   

Coagulase test Test is negative when no cluster or clumps are formed Positive test result for staph aureus witfh formation of clumps or cluster

Gram positive staphylococcus aureus is the most common organism to infect the endocardium of heart resulting in endocarditis. Gram positive staph aureus infection can affect the heart after a surgery or insertion of an iv line.

Symptoms of endocarditis include :

• fever
• Lethargy
• abnormal heart rate
• heart murmur
• increased respiratory rate