A 3-month-old male is brought to the emergency department because of fever and poor feeding for 2 days. He became very fussy the previous evening and cried for most of the night. The mother does not recall any sick contacts at home. He appears irritable. His temperature is 38.6°C (101.5°F), pulse is 180/min, and blood pressure is 82/51 mm Hg. Examination shows scleral icterus. He becomes more agitated when picked up. There is full range of motion of his neck and extremities. The anterior fontanelle feels soft and flat. A lumbar puncture is performed, and the results of cerebrospinal fluid (CSF) analysis are as follows: Gram-negative coccobacilli are isolated from the CSF. These organisms demonstrate little growth on 5% sheep blood agar but grow well when incubated on the same media alongside colonies of Staphylococcus aureus. Staphylococci promote the growth of these bacteria by supplementing which of the following substances?

Question

A 3-month-old male is brought to the emergency department because of fever and poor feeding for 2 days. He became very fussy the previous evening and cried for most of the night. The mother does not recall any sick contacts at home. He appears irritable. His temperature is 38.6°C (101.5°F), pulse is 180/min, and blood pressure is 82/51 mm Hg. Examination shows scleral icterus. He becomes more agitated when picked up. There is full range of motion of his neck and extremities. The anterior fontanelle feels soft and flat. A lumbar puncture is performed, and the results of cerebrospinal fluid (CSF) analysis are as follows:  Gram-negative coccobacilli are isolated from the CSF.  These organisms demonstrate little growth on 5% sheep blood agar but grow well when incubated on the same media alongside colonies of Staphylococcus aureus.  Staphylococci promote the growth of these bacteria by supplementing which of the following substances?

Quizplus · Accepted Answer

Eductional Objective: Haemophilus influenzae is a "blood-loving" organism that requires X (hematin) and V (NAD+) factors for growth.  This can be accomplished by growing H influenzae in the presence of Staphylococcus aureus and demonstrating the "satellite phenomenon," whereby H influenzae grow only near the B-hemolytic S aureus colonies that produce the needed X and V factors.

A 3-Month-Old Male Is Brought to the Emergency Department Because