Free ASCP MLT Exam Flashcards

Quality questions usually ask which phase failed before asking for the next action. Preanalytical = ordering/collection/transport. Analytical = the testing process (QC, calibration, instrument). Postanalytical = result review, reporting, and corrected reports.

An MLT should not release results when QC, calibration, specimen identity, instrument status, or required documentation is unresolved. The safe action is to hold, repeat, dilute, correct, or escalate before release.

A 1_2s control event is a warning. 1_3s, 2_2s, R_4s, 4_1s, and 10x patterns generally require run rejection or investigation under the lab's QC plan. Resolve QC before releasing patient results from that run.

Before release, confirm acceptable QC status, valid calibration/method status, acceptable specimen quality, plausible delta check, and correct critical-value handling. A flagged result is investigated, not auto-released.

Treat all blood and body fluids as potentially infectious. MLT safety questions emphasize bloodborne pathogen prevention, PPE, safe work practices, specimen/organism transport, SDS use, and emergency response.

Calculated from electrolytes to screen for unmeasured anions. An elevated anion gap supports a metabolic acidosis differential. On the exam, tie the calculation to patient-result interpretation, not arithmetic alone.

Solve in sequence: pH first (acidemia vs alkalemia), then pCO2 and HCO3 direction (respiratory vs metabolic), then compensation, and the anion gap if metabolic acidosis is present.

Total calcium must be interpreted with albumin because much of calcium is protein-bound. Low albumin lowers total calcium without changing the physiologically active ionized fraction; correct or interpret before calling a result abnormal.

These interferents can add analyte, alter absorbance, or create turbidity, making chemistry results look clinically urgent when the real problem is preanalytic. Recognize the specimen issue before reporting.

Hepatocellular injury emphasizes AST/ALT elevation. Cholestasis emphasizes ALP/GGT and direct (conjugated) bilirubin. Use the pattern, not a single analyte, to interpret liver chemistry.

A drug concentration is only interpretable with correct specimen timing, steady-state awareness, and toxicity correlation. A trough drawn at the wrong time can be misleading even if the number is reported.

Screening (immunoassay) results are presumptive and must be interpreted with method limits, clinical context, and confirmatory testing policy. A presumptive positive is not a final answer.

Delayed serum separation, wrong anticoagulant, IV-line contamination, light exposure, and evaporation can produce results that look like real disease. Suspect preanalytic causes before clinical conclusions.

Indices turn the CBC into a classification tool: MCV sizes the cell, MCH estimates hemoglobin per cell, MCHC reflects hemoglobin concentration, and RDW reflects size variation (anisocytosis).

Separates underproduction anemia (low/inadequate retic) from a marrow response to blood loss or hemolysis (elevated retic). Use the retic response to classify anemia, not labels alone.

An impossibly high MCHC is a classic clue to a spurious RBC result, often from cold agglutinins, lipemia, or specimen problems. Investigate the specimen and analyzer before reporting.

ANC = WBC x (% segmented neutrophils + % bands). Interpret leukocytes with absolute counts, not relative percentages alone; ANC is central to neutropenia risk assessment.

Cytoplasmic rod-shaped inclusions that support myeloid lineage and a possible acute myeloid process. Their presence should trigger urgent smear review and escalation per procedure.

Toxic neutrophil change and atypical (reactive) lymphocytes are reactive responses and must be separated from blasts or neoplastic patterns that change clinical urgency and escalation.

PT/INR screens the extrinsic and common pathways. aPTT screens the intrinsic and common pathways. Knowing which pathway each test interrogates drives the coagulation differential.

If a prolonged clotting time corrects after mixing with normal plasma, suspect a factor deficiency. If it fails to correct, suspect an inhibitor pattern.

Disseminated intravascular coagulation shows low platelets, prolonged PT and aPTT, low fibrinogen, and high D-dimer — a consumptive coagulopathy pattern requiring escalation.

A clotted EDTA tube can falsely lower platelet and WBC counts and is generally unacceptable for CBC reporting. Recollect rather than report a spurious low count.

Coagulation specimen quality is central: citrate (blue-top) tubes must be properly filled (correct blood-to-anticoagulant ratio), unclotted, and free from anticoagulant carryover, or PT/aPTT can be falsely altered.

Forward typing tests patient red cells with anti-A/anti-B reagents. Reverse typing tests patient plasma/serum against known A1 and B cells. A valid ABO interpretation requires forward and reverse agreement.

For an unresolved ABO discrepancy, stop final interpretation, check identity and history, repeat or investigate, and avoid ABO-specific component release until resolved.

Extra reverse reactions often point to cold-reactive antibodies or rouleaux. Weak/missing reverse reactions often point to age, immunosuppression, hypogammaglobulinemia, or recent transfusion.

While testing continues, the classic unknown-type defaults are group O red cells and group AB plasma, prioritizing immediate patient safety over a confirmed type.

The antibody screen detects free antibody in patient plasma/serum. The DAT detects red cells already coated in vivo with IgG and/or complement. They answer different questions.

A negative autocontrol with a positive screen suggests an alloantibody. A positive autocontrol or positive DAT raises concern for autoantibody, drug effect, transfusion reaction, or in vivo coating.

Immediate-spin or a validated electronic crossmatch is appropriate only when the antibody screen is negative and there is no clinically significant antibody history.

Match the component to the defect: red cells for oxygen-carrying capacity, platelets for platelet number/function, plasma for multiple coagulation factors, and cryoprecipitate for fibrinogen support.

Exam favorites: red cells stored at 1-6 C, platelets at 20-24 C with continuous agitation, and frozen plasma or cryoprecipitate with limited post-thaw life.

Stop the transfusion, maintain IV access with normal saline, notify the clinical team and blood bank, and begin the clerical and laboratory investigation. Stopping the transfusion comes first.

Hemolytic disease of the fetus/newborn is caused by maternal IgG crossing the placenta. Anti-D, anti-c, and anti-K are high-yield severe causes; ABO HDFN is usually milder.

RhIG prevents anti-D alloimmunization in an unsensitized Rh-negative pregnant patient when fetal/neonatal D-positive exposure is possible.

Sterile-site growth is interpreted differently from nonsterile sites, where contamination, normal flora, quantity, and inflammation change the meaning of growth.

Acceptability starts with patient ID, source, collection method, transport condition, and rejection criteria before any organism conclusion. Reject poor specimens (e.g., saliva-contaminated sputum).

The fastest ID path starts with Gram reaction, morphology, arrangement, colony features, and specimen source — then a small set of biochemical tests.

Catalase, coagulase, oxidase, indole, PYR, CAMP, bile esculin, 6.5% NaCl tolerance, urease, H2S, and optochin are core MLT-level differentiation tests.

MacConkey, chocolate, Thayer-Martin, BCYE, Lowenstein-Jensen, Sabouraud, TCBS, and mannitol salt each answer a different question. Choose media by what you need to recover or differentiate.

Acid-fast staining works because of the mycolic-acid-rich cell wall of mycobacteria. Mycobacterial workups require special processing, media, long incubation, and biosafety awareness.

Routine disk diffusion uses Mueller-Hinton agar and a 0.5 McFarland inoculum for many bacteria. Zones or MICs must be interpreted with current laboratory-approved breakpoints.

Out-of-range antimicrobial susceptibility QC is a stop-and-troubleshoot event. Affected patient susceptibility results should not be reported until QC issues are resolved per policy.

Reagent-strip results must be correlated with microscopy, specific gravity, pH, color, clarity, and specimen freshness. Discrepancies require investigation before reporting.

RBC casts suggest glomerular bleeding, WBC casts suggest renal inflammation, and broad waxy casts suggest chronic tubular stasis. Casts point findings to the kidney itself.

Rapid cell deterioration, neutrophilic pleocytosis with high protein and low glucose, organisms on Gram stain, and xanthochromia are policy-driven escalation triggers. CSF is prioritized over most other specimens.

Serous (pleural/peritoneal) fluids are decision-pattern topics: Light's criteria separate transudate from exudate, and infection or malignant-cell clues matter more than isolated memorization.

Most MLT immunology methods rest on antigen-antibody binding: agglutination, precipitation, labeled immunoassays, immunofluorescence, lateral flow, and reflex molecular testing.

Nucleic acid (molecular) tests detect pathogen genetic material; serology detects host antibody or pathogen antigen. Infectious serology often follows screen-confirm-resolve logic (e.g., HIV, hepatitis B patterns, syphilis treponemal/nontreponemal).