CSF

A CSF specimen was sent to the laboratory for analysis. A glucose, protein, and cell count were performed. Based on the following results, what would be the probable cause? AnalyteResultGlucose50 mg/dLProtein25 mg/dLLeukocytes2 cells/mm3

Normal CSF

When three tubes of cerebrospinal fluid are received in the laboratory they should be distributed to the various laboratory sections as follows:

#1 Chemistry, #2 Microbiology, #3 Hematology

When a lumbar puncture is performed, what volume of spinal fluid is needed for optimal recovery of meningitis causing organisms?

5-10 mL

The cryptococcal antigen test used to diagnosis Cryptococcus neoformans meningitis is based on what type of rapid methodology?

Latex agglutination

What virulence factor is not inherent to bacterium?

Production of opsonins

The most frequent cause of bacterial meningitis in adults and in children is:

Streptococcus pneumoniae

A patient tested positive for cryptococcal antigen and rheumatoid factor. The results of the cryptococcal antigen should be reported as?

Uninterpretable

The image on the right is a Wright-Giemsa stained CSF smear (1000X). What structures are indicated by the arrows?

Bacteria

A 3-year old girl was brought to the ER with a temperature of 103ºF, lethargy, and cervical rigidity. Three tubes of cloudy CSF were delivered to the Lab, and preliminary test results showed: WBC: 4,500/µL Differential: 88% neutrophilsGlucose: 15 mg/dL 12% lymphocytesProtein: 140 mg/dLGram stain: No organisms observed From these results, what preliminary diagnosis SHOULD the physician consider?

Bacterial meningitis

A CSF specimen is received from a patient with suspected meningitis. Positive Gram stain, along with the results shown here suggest what type of condition? Elevated WBC count Neutrophils predominant Marked protein elevation Marked glucose decrease Lactate level = 37 mg/dL

Bacterial meningitis

Spinal fluid cultures on a 3-day-old infant revealed beta-hemolytic, gram-positive cocci occurring in pairs and chains. The organism was catalase-negative and bile esculin-negative. Resistance to bacitracin was noted. The other test necessary to identify this organism is a positive test by:

CAMP

Molecular methods are commonly used for direct detection of organisms in clinical specimens. One specimen type that can be used is cerebrospinal fluid. This is important as patients who are immunocompromised can succumb to neural infections quite easily when compared to immunocompetent patients. Which of the following is an advantage of performing molecular testing on CSF patients?

Can detect viable and nonviable organisms

An immunosuppressed patient with a CSF shunt is exhibiting symptoms of a shunt infection. When performing a Gram stain, the organism observed in the image to the right is seen. What is the most likely identity of this organism?

Candida sp.

A CSF shunt tip specimen was sent to the microbiology laboratory for culture. The shunt specimen was inoculated to sheep blood agar, chocolate agar, and a thioglycollate broth. After 24 hours of CO2 and non CO2 incubation at 37°C, the sheep blood agar, chocolate agar, and the thioglycollate broth had growth. The microbiology tech evaluated the media and observed the following: Growth: Sheep blood grew small, white non-hemolytic colonies. Chocolate grew small, white colonies. Gram Stain: Gram positive cocci in clusters Biochemical: Catalase positive; coagulase negative Which of the following organisms is most likely the cause of the CSF shunt tip infection?

Coagulase negative staphylococci

The most common cause of acute meningitis associated with CSF shunts is:

Coagulase-negative staphylococci

A spinal fluid was sent to the laboratory for testing. When the hematology tech performed the cell differential, she noticed encapsulated yeast as seen in the images to the right. Upon further investigation, she determined that the patient was immunocompromised and had a recent history of pneumonia. Which of the following would be the most beneficial test to determine a diagnosis?

Cryptococcus neoformans antigen test

A CSF shunt specimen was sent to the microbiology laboratory for culture. The shunt specimen was inoculated to chocolate agar and a thioglycollate broth. After two days of incubation in CO2 at 37°C, the chocolate agar had no growth and the thioglycollate broth had growth at the bottom of the tube. The microbiology tech then subbed the thioglycollate broth to an anaerobic blood agar plate and incubated the plate in anaerobic conditions at 37C for 48 hours. After the 48 hour incubation, the anaerobic blood agar plate was evaluated: Growth: Small, white colonies were observed Gram Stain: Gram positive, pleomorphic, diphtheroid-like rod Biochemical: Catalase positive; Nitrate Reduction positive, Sensitive to Vancomycin and Kanamycin Which of the following organisms is most likely the cause of the CSF shunt infection?

Cutibacterium (Propionibacterium) acnes

Which anaerobic bacteria incidence is increasing in CSF shunt infections?

Cutibacterium (Propionibacterium) acnes

A patient with hydrocephalus had a shunt placed 3 weeks ago and is now experiencing symptoms consistent with a CSF shunt infection. When a CSF sample is sent to the microbiology department, the image on the right is observed on the Gram stain. What is the most likely cause of this CSF shunt infection?

E. coli

An organism has been isolated from the CSF of a premature newborn. The organism grew in 48 hours on MacConkey and blood agar (see image). Additional reactions include: Alk/Alk (red over red) on Kligler Iron agar, oxidative utilization of carbohydrates and a positive indole reaction. Which of the follwing is the most likely identification?

Elizabethkingia (Flavobacterium) meningosepticum

Elizabethkingia is the new genus name for the bacterium formerly called Chryseobacterium meningosepticum, an important agent of neonatal mentingitis (now E. meningoseptica). What biochemical characteristic is unique for the family Flavobacteriaceae among the nonfermenters?

Indole production

A beta-hemolytic gram-positive cocci, isolated from the CSF of an infant, grew on sheep blood agar under aerobic conditions and was resistant to a bacitracin disc. Which of the following tests should be performed for the presumptive identification of the organism?

Latex agglutination test

An organism isolated from the spinal fluid of a newborn produced small, grayish, slightly translucent beta-hemolytic colonies on sheep blood agar. A Gram stain of the colony showed small Gram-positive rods that look like diphtheroids. The organism is MOST likely:

Listeria monocytogenes

A patient came into the emergency department with symptoms of meningitis. The patient was suspected of having a blocked cerebral shunt, which can cause meningitis. The shunt was drained and sent to the microbiology laboratory for culture. All of the following organisms are associated with shunt infections EXCEPT?

Neisseria meningitidis

An 18-year-old student was seen in the college health center with a sudden onset of headache, fever and stiff neck. A gram stain of the cerebral spinal fluid sediment is shown in the photograph to the right. The MOST likely cause of this patient's acute meningitis is:

Neisseria meningitidis

An organism grew out of a spinal shunt. The protocol for growth of this organism is to notify infection control and the public health department. In addition, any health care worker who came in contact with the patient must be treated promptly with antibiotic prophylaxis. Which of the following organisms requires this type of protocol?

Neisseria meningitidis

Small intracellular gram-negative cocci were observed in a centrifuged spinal fluid sediment as presented in the upper photomicrograph. A clinical diagnosis of meningitis was suspected. Yellow-gray colonies after 24-hour incubation had been observed on blood agar. Based on the carbohydrate utilization tube reactions observed in the lower photograph, what is the presumptive identification of this isolate.

Neisseria meningitidis

The FilmArray meningitis/encephalitis panel is a multiplex panel that detects all of the following microorganism types, EXCEPT?

Parasites

Immunosuppressed or diabetic patients with ketoacidosis may present with symptoms of a brain abscess caused by which of the following?

Phycomycosis

A Staphylococcus species recovered from a CSF shunt culture was found to produce acid from sucrose and maltose and showed alkaline phosphatase activity. The Staphylococcus was also coagulase negative. The most likely identification is:

Staphylococcus epidermidis

A CSF specimen was sent to the laboratory for analysis. A glucose, protein, and cell count were performed. Based on the following results, what would be the probable cause? AnalyteResultGlucose15 mg/dLProtein150 mg/dLLeukocytes1,000 cells/mm3 neutrophils

Purulent infection

Gram stain of a spinal fluid revealed pleomorphic, gram-negative rods. Colonies that appeared on chocolate agar after 24 hours of incubation were gray, opaque, and medium in size. A musty odor was noted when the plate was opened. Gram stain of the colonies on chocolate agar showed small, gram-negative coccobacilli. No growth was seen on sheep blood or MacConkey agar. The next step taken by the technologist to identify this isolate would be to show that the organism:

Requires X and V factors

What is the most common agent of infection in CSF shunts?

Stahpylococcus sp.

A mixture of Gram positive and Gram negative bacteria may be present within the same field of a slide of all of the following EXCEPT:

Sterile cerebrospinal fluid

Which of the following organisms is the leading cause of bacterial meningitis in infants, young children, and adults in the United States?

Streptococcus pneumoniae

Which organism is associated with sinusitis and otitis and is also considered a leading cause of meningitis with or without bacteremia?

Streptococcus pneumoniae

A CSF spinal shunt specimen grew out an Enterococcus species. What parasitic species should be of concern when an Enterococcus species is isolated from a spinal fluid?

Strongyloides stercoralis

A cerebral spinal fluid was collected from a lumbar puncture to evaluate for possible meningitis. Four tubes were collected and sent to the microbiology laboratory for analysis. Which of the four tubes is preferred for microbiology studies?

Tube 2

Which of the following tests would you employ to examine a CSF for syphilis:

VDRL

A CSF specimen was sent to the laboratory for analysis. A glucose, protein, and cell count were performed. Based on the following results, what would be the probable cause? AnalyteResultGlucose50 mg/dLProtein100 mg/dLLeukocytes80 cells/mm3 mononuclear

Viral infection