Practice Test Geeks(MLS) Medical Laboratory Scientist Practice Test
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Diagnostic Procedures & Reporting Flashcards

7 cards from real MLS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.

Read the first 7 Diagnostic Procedures & Reporting flashcards as text

  1. Which of the following organisms requires both an alkaline (pH 8.6) peptone water enrichment and TCBS agar for optimal isolation from stool?

    Answer: Vibrio cholerae

    Vibrio cholerae grows optimally in alkaline conditions; alkaline peptone water enrichment followed by plating on TCBS (thiosulfate-citrate-bile salts-sucrose) agar is the standard isolation method.

  2. A patient's serum creatinine is 1.1 mg/dL. The estimated GFR (eGFR) calculated using the CKD-EPI equation is 68 mL/min/1.73m². This result best reflects:

    Answer: Mildly decreased kidney function (eGFR 60–89)

    An eGFR of 68 mL/min/1.73m² falls in the G2 CKD category (60–89), indicating mildly decreased kidney function; normal is ≥90 mL/min/1.73m².

  3. A synovial fluid specimen shows positively birefringent (yellow when parallel to polarizer) needle-shaped crystals. This is most consistent with:

    Answer: Calcium pyrophosphate dihydrate crystals (pseudogout)

    Calcium pyrophosphate dihydrate (CPPD) crystals are positively birefringent (yellow parallel to the red compensator) and rhomboid to rod-shaped, distinguishing them from the negatively birefringent MSU crystals of gout.

  4. A laboratory receives a specimen labeled only with a room number and no patient identifiers. The appropriate action is:

    Answer: Reject the specimen and notify the clinical area to recollect

    Two patient identifiers are required on every specimen; a label missing patient-specific identifiers renders the specimen unacceptable and it must be rejected to prevent patient identification errors.

  5. Which immunoglobulin class is produced first during a primary immune response and is the predominant antibody detected in ABO blood grouping (back type)?

    Answer: IgM

    IgM is the first antibody produced in a primary immune response and is the class responsible for naturally occurring ABO antibodies (anti-A and anti-B) detected in the reverse (back) type.

  6. An HIV-1/2 antigen/antibody combination (4th-generation) immunoassay is reactive. The confirmatory algorithm's next step is:

    Answer: HIV-1/HIV-2 antibody differentiation immunoassay

    Current CDC/APHL guidelines recommend an HIV-1/HIV-2 antibody differentiation immunoassay as the second step following a reactive 4th-generation combination test to distinguish HIV-1 from HIV-2 infection.

  7. A fasting plasma glucose of 128 mg/dL is reported. According to ADA criteria, this single result is:

    Answer: Diagnostic of diabetes mellitus if confirmed on a repeat test

    A fasting plasma glucose ≥126 mg/dL meets ADA criteria for diabetes mellitus; one result is sufficient in the presence of symptoms, but confirmation with a repeat test on a separate day is required in asymptomatic patients.