Microbiology Test 4

Beta-hemolytic gram-positive cocci are isolated from the cerebrospinal fluid of a 2-day-old infant with signs of meningitis. The isolate grows on sheep blood agar under aerobic conditions and is resistant to a bacitracin disc. Which of the following should be performed for the identification of the organism?

A 4-year-old is admitted with symptoms of meningitis, and a Gram stain of the cerebrospinal fluid reveals small, pleomorphic, gram-negative coccobacilli. After 24 hours incubation at 35C, small, moist, gray colonies, which are oxidase variable, are found on the chocolate agar plate only. Which of the following biochemical data would be consistent with this isolate?

A technologist is reading a Gram stain from a CSF and observes many intracellular gram-negative diplococci. Which set of chemistry and hematology CSF results would most likely be seen in someone with this type of infection?

An 18-year-old boy is admitted to the hospital with suspected meningitis. He is lethargic and presents with a rigid neck. He has not had most of the recommended vaccines from childhood to now. Gram stain of hi spinal fluid shows many PMNs with intra-and extracellular gram-negative diplococci. The suspected pathogen is:

A 25-year-old man who had recently worked as a steward on a transoceanic grain ship presented to the emergency room with high fever, diarrhea and prostration. Axillary lymph nodes are hemorrhagic and enlarged. A Wright-Giemsa stain of the aspirate shows bacilli that are bipolar, resembling safety pins. The most likely identification of this organism is:

Anaerobic gram-positive bacilli with subterminal spores are isolated from a peritoneal abscess. The colony has a swarming appearance. The most likely identification of this organism is:

A Gram stain of a peritoneal fluid shows large gram-positive bacilli. There is 3+ growth on classic identification of the organism, the microbiologist could:

An organism from a peritoneal abscess is isolated on kanamycin-vancomycin laked blood agar and grows black colonies on BBE agar. It is nonpigmented, catalase-positive, and indole-negative. The genus of this organism is:

Thin, gram-negative bacilli with tapered ends isolated from an empyema specimen grow only on anaerobic sheep blood agar. They are found to be indole-positive, lipase-negative, and are inhibited by 20%o bile. The most probable identification of this isolate would be:

A 10-year-old child with cystic fibrosis presents with cough and shortness of breath.

Her sputum Gram stain is seen in the image:

Based on the Gram stain, the best medium and incubation condition to optimize recovery of the organism seen is:

A sputum culture from an alcoholic seen in the ER grows gray, mucoid, stringy colonies on sheep blood agar. The isolate grows readily on MacConkey agar and forms mucoid, dark pink colonies. The colonies yield the test results shown in this table:

The organism is most likely:

A patient with a nosocomial pneumonia has a sputum Gram stain that shows many neutrophils and numerous small gram-negative coccobacilli. The organism grows in 24 hours as a mucoid, hemolytic colony on blood agar and as a colorless colony on a MacConkey agar. The organism has the characteristics shown in this table:

The organism is:

Serum samples collected from a patient with pneumonia demonstrate a rising antibody titer to Legionella. A bronchoalveolar lavage (BAL) specimen from this patient has a positive antigen test for Legionella, but no organisms are recovered on buffered charcoal yeast extract medium after 2 days of incubation. The best explanation is that the:

A 17-year-old female with cystic fibrosis is diagnosed with pneumonia. A sputum sample grows gram-negative bacilli with yellow, smooth colonies that have the biochemical reactions shown in this table:

The most likely organism is:

A college student who recently studied a semester abroad in Southeast Asia is admitted to the hospital with a diagnosis of “glanders-like” infection (melioidosis). A sputum specimen grows small, gram-negative bacilli that are positive for oxidase, reduce nitrate to gas, and oxidize glucose, lactose, and mannitol. What is the most likely organism?

An organism previously thought to be nonpathogenic, Moraxella catarrhalis, is now known to be associated with opportunistic respiratory infection and nosocomial transmission. Characteristic identification criteria include:

An organism recovered from a sputum has the following characteristics:

These results are consistent with which of the following genera?

The Gram stain of drainage from a pulmonary sinus tract shows many WBCs and 3+ branching gram-positive bacilli. Colonies grow only on anaerobic media after 3 days incubation. They are yellow-tan and have a molar tooth appearance. The most likely genus is:

A 1-2 mm translucent, nonpigmented colony, isolated from an anaerobic culture of a lung abscess after 72 hours, is found to fluoresce brick-red under ultraviolet light. A Gram stain of the organism reveals coccobacilli that have te characteristics shown in this table:

The identification of this isolate is:

Psittacosis is transmissible to man via contact with: