MLT GlobeASCP exam preparation (USA · MLS / MLT)
1200 practice MCQs for the ASCP medical laboratory exam. Level: Advanced.
Subject mix: Hematology 20%, Chemistry 20%, Blood Banking 19%, Bacteriology 14%, Immunology & Serology 8%, Urinalysis & Body Fluids 8%, Laboratory Operations 6%, Mycology 2%, Parasitology 2%, Virology 1%
Rouleaux on the smear, a monoclonal band on serum protein electrophoresis and more than 10% clonal plasma cells in the marrow indicate:
Excess monoclonal immunoglobulin coats red cells and causes rouleaux. A monoclonal (M) protein plus at least 10% clonal marrow plasma cells, with end-organ damage, defines multiple myeloma.
Which plasma group can be given to patients of any ABO group?
Group AB plasma has neither anti-A nor anti-B, so it will not attack any recipient's red cells. For red cells the rule is reversed: group O is the universal donor.
In serum protein electrophoresis at pH 8.6, which fraction migrates farthest toward the anode?
At pH 8.6 serum proteins are negatively charged and move to the anode. Albumin has the most negative charge for its size and moves farthest; the order is albumin, alpha-1, alpha-2, beta, gamma.
A near-absent alpha-1 band on serum protein electrophoresis in a young adult with emphysema suggests deficiency of:
Alpha-1 antitrypsin makes up most of the alpha-1 band. Its deficiency leaves proteases unchecked in the lung (early emphysema) and can cause liver disease.
A potassium of 6.9 mmol/L is reported on a visibly hemolysed sample from a well patient with a normal ECG. The most likely cause is:
Red cells contain far more potassium than plasma, so hemolysis falsely raises the result (pseudohyperkalemia). The sample should be recollected before acting on the value.
A boy with joint bleeds has a prolonged aPTT, normal PT and normal platelet count. The most likely deficiency is:
Hemarthrosis in a male with an isolated long aPTT points to hemophilia A (factor VIII), X-linked and the most common. Factor IX deficiency (hemophilia B) looks the same and is separated by factor assays.
A catalase-positive gram-positive coccus in clusters that is coagulase positive is identified as:
Coagulase, which clots plasma, is the key marker of S. aureus among human staphylococci. S. epidermidis and S. saprophyticus are coagulase-negative.
Howell-Jolly bodies are nuclear (DNA) remnants most commonly seen after:
The spleen normally removes these small round DNA fragments from red cells. After splenectomy or in functional asplenia (e.g. sickle cell disease) they stay in circulating cells.
Cryoprecipitate is the component of choice to replace:
Cryoprecipitate is made by thawing FFP at 1-6 °C. It is rich in fibrinogen, factor VIII, von Willebrand factor, factor XIII and fibronectin, and is used mainly for low fibrinogen.
Cellular blood components are irradiated to prevent:
Gamma or X-ray irradiation stops donor T lymphocytes from dividing, so they cannot attack the recipient. It is needed for immunocompromised patients, intrauterine transfusions and blood from relatives.
The direct antiglobulin test (DAT) detects:
The DAT tests the patient's own red cells with anti-IgG or anti-C3d to find in vivo coating, as in HDFN, transfusion reactions and autoimmune hemolysis. The indirect test (IAT) finds free antibody in plasma.
Thayer-Martin agar is used to isolate:
Thayer-Martin is chocolate agar with vancomycin, colistin and nystatin (plus trimethoprim in modified forms). These inhibit the normal flora of genital sites so pathogenic Neisseria can grow.
Which immunoglobulin is the first produced in a primary immune response and is the most efficient at activating complement?
IgM, a pentamer with ten binding sites, appears first after new exposure. A single IgM bound to an antigen can activate C1, whereas IgG needs two molecules close together.
The minimum interval between two whole blood donations by the same donor is:
An interval of 8 weeks (56 days) lets the donor replace iron and red cells. Longer intervals apply after double red cell apheresis (16 weeks).
A young woman with weight loss, tremor and exophthalmos has suppressed TSH, high free T4 and positive TSH-receptor antibodies. The diagnosis is:
TSH-receptor stimulating antibodies drive the thyroid in Graves disease, raising T4 and suppressing TSH. Eye disease is specific to Graves.
For therapeutic drug monitoring, a trough level should be drawn:
The trough is the lowest concentration, just before the next dose, and shows whether levels stay therapeutic without accumulating. Peaks are timed after absorption and distribution.
A single control result outside ±3 SD violates the Westgard 1-3s rule and most often signals:
1-3s is a rejection rule mainly sensitive to random error (e.g. pipetting, bubbles). Patient results must not be released until the cause is found and corrected.
Which extinguisher is appropriate for a fire in an electrical instrument (US class C)?
Water and foam conduct electricity and risk electrocution. CO2 or dry chemical extinguishers are used; switch off the power if it is safe to do so. (Class A: ordinary combustibles, B: flammable liquids, D: metals.)
A reactive RPR in a pregnant woman should next be confirmed with:
RPR and VDRL detect non-treponemal (reagin) antibodies and give biological false positives in pregnancy, SLE and some infections. Treponemal tests detect antibodies to T. pallidum itself.
The genes that encode the ABO glycosyltransferases are located on which chromosome?
The ABO gene is on chromosome 9q34. Chromosome 1 carries the RH genes, and chromosome 19 carries the H (FUT1), Se (FUT2) and Le (FUT3) genes.