MLT BOC questions

In blood, bicarbonate leaves the red blood cell and enters the plasma through an exchange mechanism with:

chloride

What is a cause of metabolic alkalosis?

excessive vomiting

Plasma cells

have a characteristic perinuclear hof not seen in monocytes, atypical lymphocytes, or blasts. This area stains lighter than the nucleus and is right above where the Golgi sits

cells common in leukemia with CNS involvement

immature cells (blasts) look for prominent nucleoli and a large nucleus-to-cytoplasm ratio

diabetes insipidus (DI)

insufficient secretion of antidiuretic hormone (vasopressin) which causes the body to be unable to reabsorb water in the kidneys. This type of diabetes is associated with an increased thirst and cravings for ice, along with very high volumes of diluted urine. Diabetes insipidus patients usually do not exhibit positive urine glucose results

cells common in viral meningitis

lymphocytes

Insect vector for Loa loa (African eye worm disease)

mango fly

Insect vector for plasmodium spp. (malaria)

mosquito

cells common in bacterial meningitis

neutrophils

Insect vector for Trypanosoma cruzi (African sleeping sickness)

reduviid bug

A cytospin from the CSF of a patient with disseminated retinal blastoma demonstrating a large tumor cell clump with occasional mitotic figure.

report tumor cells, send to pathologist prior to reporting findings

kaizen workshop

short-term events used to introduce lean tools and techniques

skeletal deformations are most commonly present in which of the following beta thalassemias?

Beta thalassemia major

Primary function of antibodies

Binding with antigens

When treating serious enterococci infections, both a cell wall-active agent, such as ampicillin or vancomycin, and an aminoglycoside, such as gentamicin should be used. Therefore, it is important that this information be reported to physicians by which of the following?

By providing an explanatory note stating the recommended use of combination therapy

RBC casts in urine

RBC casts may appear as brown to almost colorless. Red cells can clearly be seen within the cast. This type of cast is diagnosis of glomerular disease or intrarenal bleeding.

Chronic transplant rejection

Rejection of an organ or tissue occurs later than three months after transplantation. The predominant mechanism is cell-mediated. The cause is disturbance of host-graft tolerance. This rejection occurs in most graft recipients. It is a slow but continual loss of organ function over months or years. This rejection is often responsive to various immunosuppressive therapies

Accelerated transplant rejection

Rejection of an organ or tissue occurs within 2 to 5 days after transplantation. The predominant mechanism is cell mediated. The cause is previous sensitization to donor antigens. This rejection is caused by activation of the T cell mediated response

cells common in allergic reactions

basophils

Your community hospital is considering the addition of a new hematology screening test. The laboratory is asked to calculate the total cost of quality control per new test. Quality Control must be performed three times per day (every eight hours). The labor cost per quality control test is $8.95 each. A days worth of Quality control reagent cost $23.62. What is the total quality control cost her new hematology test if 6700 of these new tests are performed each year?

$2.75 1. If quality control is run three times per day, a total of 1095 quality control runs are performed each year (3 x 365=1095) 2. The direct labor cost of $8.85 multiplied by 1095 quality control runs equals $9800.25 per year in Quality Control direct labor 3. The hospital pays $23.62 per day on Quality Control consumables, which equals $8621.30 per year ($23.62 x 365= $8621.30) 4. The total Quality Control cost in a year are equal to $9800.25 + $8621.30= $18421.55 If 6700 new tests are performed each year, the total QC cost per new hematology test will be $2.75 ($18421.55/6700= $2.75)

Beta-thalassemia

A decrease in the rate of production of beta chains due to a partial or total deletion of loci from chromosome 11 that code for the beta chain Beta thalassemia demonstrates problems with beta globin chain production. One or two Loci that code for the beta chains may be deleted from chromosome 11. The greater the number of loci deleted or inactivated, the greater the severity of the anemia that develops

Root Cause Analysis

A method that is used to determine what caused a quality or performance problem for the purpose of correcting the primary cause of the problem

Fontana-Masson Stain

A stain that is used to detect fungal elements in tissue samples. The stain binds to the cell wall with melanin to observe phaeoid fungi

Process of performing a bone marrow differential

1. Record patient and sample information 2. Check for fragments 3. Review stain and smear quality 4. Scan for tumor cells, cellularity, megakaryocytes using the 10x objective 5. Add oil and perform differential using the 100x (oil) immersion objective 6. Calculate the M:E ratio, record cellularity, megakaryocytes 7. Send it to hematopathologist for final review and interpretation

A 45-year-old male average height and weight has a serum creatinine of 1.5 mg/dL and a urine creatinine of 120 mg/dL; the total volume of urine collected over a 24 hour period was 1800 mL. Calculate the creatinine clearance for this patient in milliliters per minute.

100 mL/min Creatinine clearance (mL/min)= (urine creatinine/ serum creatinine) x urine volume (mL)/ [time (hr) x 60] =(120/1.5) x (1800/ [24 x 60]) =(80) x (1800/1440) = 80 x 1.25 = 100

In the steps involved in performing a bone marrow differential what objective is used and how many cells must be counted?

100x (oil), 200 cells

Following the treatment of an IgG molecule with papain, which of the following will remain?

2 fab fragments each with a light chain and a partial heavy chain attached with a disulfide bond

In a closed system, thawed FFP & PF24 blood components may be labeled as thawed plasma 24 hours after the original thaw time and given a shelf-life of:

5 days Thawed FFP & PF24 components expire within 24 hours from the date and time thawed. After 24 hours have elapsed from the date of the following, the FFP and PF24 components may be labeled as "thawed plasma" and allowed a 5-day shelflife

What is the corrected blood cell count if the WBC is 14,460 and there were 47 nucleated red blood cells per 100 white blood cells noted on a differential count?

9,837 Corrected WBC count= uncorrected WBC count x (100/NRBCs+ 100) Corrected= 14,460 x (100/47+100) Corrected= 14,460 x (100/147) Corrected= 14,460 x 0.68 Corrected= 9,837

What ABO phenotype will exist in a individual that inherits an A gene from one parent and a B gene from the other

AB The majority of blood group antigens or inherited any autosomal codominant manner. In this pattern of inheritance, the phenotype each allele will be present. Since the individual inherited an A allele and a B allele, the individuals phenotype will be AB

FFP given to AB negative patient

AB neg or AB pos only FFP should be a be ABO compatible with the patient's red blood cells. It can be given without regard to Rh type because it does not contain the cells with the D antigen for the recipient to react to.

The type of graft rejection that occurs approximately 1 to 3 weeks after tissue or organ transplantation is:

Acute Acute rejection of an organ or tissue occurs from 7-21 days after transplantation. The predominant mechanism is cell mediated, possibly antibodies cell mediated cytotoxicity. The cause of rejection is development of allogenic reaction to donor antigens. Acute rejection can resort after first exposure to alloantigens.

Important applications of PCR include:

Amplification of DNA, identification of a target sequence, synthesis of an anti-sense probe The search for mutations with large deletions in PCR product sequence is not an application of the PCR technique. In fact, it is a weakness. Only short sequences can be amplified

Hashimoto's disease

And endocrine disorder and a classic example of an organ-specific autoimmune disease. In this example, the autoimmune process in which the development of circulating cytotoxic antibodies eventually destroy the thyroid gland and produce hypothyroidism. Organ-specific autoimmune disease are produced by T cells or antibodies against antigens restricted to a single organ. In Organ-specific diseases, both the lesions produced by tissue damage and the auto antibodies are directed at the same organ

Quellung reaction

Antibodies to bind to the bacterial capsule, which can be used to identify serotypes of streptococcus pneumoniae

Weil-Felix Reaction

Assays for anti-rickettsial Abs, which cross-react w/ Proteus Ag. Weil-Felix is usually positive for typhus and Rocky Mountain spotted fever, but negative for Q fever.

Cold Agglutination test

Auto antibodies that can cross-react with RBCs. They cause RBCs to clump together when the person is exposed to cold temperatures and increases the chances of those RBCs to get destroyed

The "recognition unit" of the classical complement pathway refers to:

C1q C5b, C6, C7, C8, and C9 make up the membrane attack complex C3a works as a natural substrate on C4b2a C4, along with C2, are part of the classical complement pathway

Two biomarkers that are not specific to cardiac muscle and may be elevated in patients with injury to muscle other than cardiac muscle

CK-MB and myoglobin CK-MB and myoglobin are present in skeletal muscle and can be elevated in injury to the cells. Other causes of increased myoglobin and CK-MB levels include: - severe injury to skeletal muscle - strenuous exercise - extremely difficult breathing - kidney failure - chronic muscle disease - alcohol abuse CK-MB it's relatively cardio specific, but small amounts of CK-MB are also present in skeletal muscle, uterus, and prostate, therefore Tnl and TnT are better for assessing myocardial damage

Suppose a patient with stiffness in her fingers has a positive ANA test with a centromere pattern at a 1:1280 titer. What is the most likely diagnosis?

CREST syndrome Centromere antibodies are present in over half of the patients with CREST syndrome, an acronym named after the major features of this auto immune disorder: calcinocis, Raynaud's phenomenon, esophageal dysmotility, sclerodactyly, and telangiesctasia

Rapid urine screening test that can be performed to detect presence of staphylococcus species:

Catalase test

Formed elements that may be present in urine sediment

Cells, casts, crystals Protein alone is not a formed element and it cannot be identified microscopically

Central tolerance in the human immune defense system operates by:

Clonal deletion of T cells and clonal editing of B cells Central tolerance is characterized by elimination of immature lymphocytes in primary lymph organs. It is controlled by a mechanism of clonal deletion of T cells and clonal editing of B cells. There are layers of self tolerance in the human immune system influenced by cellular activity and soluble mediators. The bone marrow and thymus are sites of action of central tolerance. Central tolerance is initiated during fetal development by the elimination of cells within the potential to react strongly with self antigens

cellophane tape test

Detecting pinworm eggs by collecting from the skin across the anal opening.

An example of a laboratory test that can be performed and interpreted by individuals who are not trained laboratory personnel is:

Dipstick urinalysis

The best technique for monitoring the severity of hemolytic disease of the fetus and newborn (HDFN) is:

Doppler ultrasound Doppler ultrasonography can Measure blood flow velocity, which allows for the severity of fetal anemia to be determined without invasive measures. This creates a safer alternative than aminocentesis Aminocentesis is a useful method that can demonstrate the severity of HDFN, but the process is invasive and, therefore, not as safe to perform as Doppler ultrasonography Antibody titration is useful for determining when other procedures, such as Doppler ultrasonography, should be performed. However, the cut off level of antibody is not standardized among facilities, and the antibody titer does not provide a definitive correlation with HDFN severity

What is the correct procedure when using a butterfly to draw a light-blue top intended for a coagulation test if this is the first tube that will be collected in the draw?

Draw and discard a waste light-blue top tube before the tube that will be used for coagulation studies The waste tube is drawn first to remove the air in the tubing of the winged collection device. The waste tube must also be a light blue tube or a tube that contains no additives or anticoagulants. A red top tube that contains a clot activator cannot be used, as the clot activator can transfer to the blue tube and affect test results Once blood flows through the tubing, the waste tube can be removed and discarded. The waste tube does not need to be completely filled. If the air is not displaced from the tubing into a waste tube, it will be drawn into the tube used for testing and can cause a short fill of the tube. End it in adequately fill tube will alter the required blood-to- anti-coagulat ratio needed for coagulation studies, thus adversely affecting results.

Which of the blood group antigens are most susceptible to destruction by the action of enzymes?

Duffy (Fya, Fyb) antigens are destroyed during treatment with enzymes.

Serological tests used for the Dx of Q-fever

EIA or indirect immunoflouresence

For the diagnosis of SLE which of the following principles provides the highest specificity?

ELISA

5S

Eileen quality improvement method that, if followed, will create a safe and efficient work environment

Which organism will cause amebiasis and is considered pathogenic?

Entamoeba histolytica

Which specimen processing technique is based on the principle that parasites are heavier than the sample debris and will be present in the settlement after being processed?

Ethyl acetate concentration An easy way to remember the terms is that an ethyl acetate concentration procedures, the parasites typically end up in the concentrate (sediment) whereas in flotation, the parasites float and maybe found in the supernatant layer

Factor requirements for Haemophilus influenza

Factor X and V are both required for growth

Sudan III confirms the presence of:

Fat

The most reliable method for determining the appropriate dosage of Rh immune globulin to give to an identified Rh immune globulin candidate after delivery is

Flow cytometry The KB test is quantitative, but the test cannot be performed quickly and is subjective

A large number of antigen detection procedures and assays are available to diagnose clinically suspected parasitic diseases in the absence of finding ova or other forms of parasites in stool preparations or other body fluids. Antigen positive staining green dots at sites where small drops of duodenal aspirated fluid has been applied to the test reagents. Trophozoites of this protozoan occupy the upper G.I. tract and the excreted over may not find the way down the long stretch of bowel to be excreted in stool specimens

Giardia duodenalis It is not uncommon, particularly in cases of light infections, that one of any number of acid to detect Giardia antigens may be performed on duodenal secretions when Giardisis is clinically suspected. Giardia trophozoites primarily occupy the upper intestine, particularly the duodenum, and the low number of ova produced may not reach the caecum and may not be observed in stool specimens. Antigen assays may also be performed to determine if a patient has been cured after treatment

Which analyte may be falsely decreased due to a delay in transport time to the laboratory?

Glucose With a prolonged period of time between blood sample collection and arrival to the laboratory for processing, the metabolic process of the viable blood cells continue, including the metabolism of the available glucose

Antigens classified as MHC I

HLA-A, HLA-B, HLA-C Found on the surface of platelets, leukocytes, and most nucleated cells

Antigens classified as MHC II

HLA-DR, HLA-DP, HLA-DQ Found on antigen-presenting cells

The appearance of small colonies, growing adjacent to large staphylococcus aureus colonies on the surface of the blood sheep agar plate indicate the need for factor V growth. This is confirmed by the VX filter paper test in which growth is observed only around the V impregnated strip, but not around the X filter paper disk. Factor X is included in the agar medium. With these observations, what is the name of this isolate

Haemiphilus parainfluenzae Distinctive growth on sheep blood agar plate surrounding staphylococcus colonies from which factor V is being provided leads to a presumptive identification of hiaemophilus parainfluenzae.

Which parasite corresponds with the sandfly as its insect vector?

Leishmania spp.

Conditions associated with an increase of alpha-fetoprotein

Hepatocellular Carcinoma, viral hepatitis, testicular tumors, liver cirrhosis, and gastric cancers can have an associated increased AFP level *** increased alpha-fetoprotein levels in adults is usually associated with hepatocellular carcinoma, as it is a tumor marker in this population AFP is not found in increased levels in patients with prostate cancer. PSA, or prostate specific antigen, is commonly used to screen for prostate cancer, not AFP

Conditions that would argue in favor of therapeutic drug monitoring (TDM)

If the drug is given chronically drugs that are highly protein bound are good candidates for TDM since changes in plasma binding proteins can affect drug levels A drug that has low toxicity and rare side effects will probably not need TDM If the effective concentration and toxic concentrations are not well defined, TDM will not be useful because there is no reference for comparison

Patience with what condition would benefit most from washed red cells?

IgA deficiency with anti-IgA Washing not only reduces the number of leukocytes and platelets that are often responsible for febrile reactions, it also eliminates plasma proteins, such as IgA Washing does not remove antigens from the red blood cells

Alkaline Phosphatase (ALP)

Increased levels of ALP are found in patients suffering from instructed jaundice. This enzyme is optimally active around a pH of 9.0 to 10.0 and is increased in bone disorders involving osteoblasts such as Paget's disease.

If a bacteria produces the enzyme tryptophanase to break down the amino acid tryptophan, which of the following tests will be positive with Kovacs reagent?

Indole test

A 56-year-old female was taken to the emergency room in a coma by her employer's nurse. She had lost 35 pounds in three months; she was always thirsty; drinking a lot of water and running to the bathroom. pH: 7.11 (7.35-7.45) pCO2: 21 (35-45 mm Hg) Glucose: 950 (60-110 mg/dL) Serum osmolality: 365 (275-295) Urine ketone: strongly POS Urine glucose: strongly POS what is the most likely cause of this patient's symptoms?

Insulin-dependent diabetes mellitus Insulin-dependent diabetes mellitus is associated with a lack of insulin, which leads to increase blood in urine glucose. The classical symptoms of polyuria, polydipsia (increased thirst), polyphagia (increased hunger)a, and weight loss. Since this patient has not been diagnosed and appears to be poorly controlled, she developed hyper osmotic non-ketonic coma (HONK) which led to her acidosis and elevated osmolality. The ketones and glucose in the urine indicate that the body is not able to use the glucose present, since there is a lack of insulin, and that the body is using fat for a source of energy instead

Monolayer of smear

Is the area of the smear where red blood cells are evenly distributed, barely overlap, and have a nice central pallor.

Characteristics consistent with the Kidd blood group system

Jk(a-b-)red cells are resistant to lysis in 2 M urea Antibodies to kid system antigens are enhanced with ficin. Most antibodies to Kidd antigens are IgG and prefer to react at AHG phase

Methotrexate is a highly toxic medication that blocks DNA synthesis in all cells. What medication needs to be administered after it to prevent cytotoxic effects in normal cells of the body?

Leucovorin Failure to administer it results in extremely cytotoxic effects to most cells in the body

Sources of serum alkaline phosphatase

Liver, placenta, intestine, bone

The hematology laboratory is experiencing instrument downtown. The laboratory has a back up method for hemoglobin and hematocrit testing that is being used until the instrument is repaired. The hematologist calls and ask if you can provide any of the red blood cell and disease. Which of the indices, if any, can you provide for the hematologist?

MCHC only Hemoglobin and hematocrit are required to calculate MCHC. Since both of these values are available from the back up instrument, MCHC can be calculated

A tall peak in the beta region, with decreased normal immunoglobulins in the games region. This is most likely due to:

Multiple myeloma

Creatinine excretion correlates best with which parameter?

Muscle mass Creatinine and excretion is related to muscle mass and is fairly constant from day-to-day for a given individual. Plasma concentrations of creatinine are used to assess renal function. Creatinine clearance is based on the serum creatinine level and is used to measure glomerular filtration rate

Granulocytes include

Neutrophilic Band, Basophil, Mast cell Though they could almost appear granulated, Mott cells are plasma cells containing Russell's bodies (accumulation of immunoglobulins in cytoplasm). Plasma cells are activated lymphocytes, and thus not granulocytes which derive from myeloid lineage.

initial aPTT: 63 sec (normal: 21-34) Immediate aPTT mixing study: 26 sec Incubated aPTT mixing study: 65 sec Has the aPTT been corrected by the mix? Is a factor deficiency or a coagulation inhibitor the more likely cause of the patients for long aPTT

Not corrected, coagulation inhibitor These results show that no correction has taken place initially it appears that the aPTT corrects. However, after the incubation time, the APTT is again prolonged. This means that a weak or slow-acting coagulation inhibitor may be present and an extended incubation time is needed to reveal the inhibitor. These results are characteristic of a factor VIII inhibitor, for example

An example of an anticonvulsant drug

Phenobarbital

Bacterial contamination is most likely in what blood products?

Platelets Bacterial contamination of platelets is more likely because they are stored at room temperature.

The condition most likely to predispose a person to septicemia by viridans streptococci is

Poor oral hygiene The oropharynx is thought to be the source of most cases of viridians streptococcus with organisms entering the tissue during dental or surgical procedures. Poor oral hygiene and periodontal disease may be the precursor to bacteremia with viridians strep, especially in immunocompromised patients

Which reagent should be used in conjunction with calcoflour white when preparing the fungal slide for interpretation?

Potassium hydroxide (KOH) KOH is used to break down the Keratin and skin layers to more clearly reveal fungal elements present in the sample. Calcoflour white binds to the polysaccharides present in the chitin of the fungus. This smears must be viewed using a fluorescent microscope with fungal elements appearing Apple green or blue-white depending on the filter used

What accelerates the rate of lipase activity in the body?

Presence of bile salt

Which of the following statements is true for the reagent strip procedure?

Prolonged immersion may wash out reagents and affect test results

The selectivity of an ion-selective electrode is determined by:

Properties of the membrane used

Within a run, one control is +2SD and the other one is -2SD units from the mean. What are these results indicate?

R4s rule is violated due to random error One control value exceeding +2SD and another exceeding -2SD is hoe the R4s rule is violated.

What physiological factor causes sedimentation in the erythrocyte sedimentation rate (ESR)?

Rouleaux formation The stacking of the red blood cells, a phenomenon known as rouleaux formation, is the physiological principle behind ESR methods The reference range for a male or child is 0-10 mm/hr while the reference range for a female is 0-20 mm/hr Increased ESR levels could be an indication of the inflammation or infection. Increasing plasma proteins (primarily acute phase proteins such as CRP) seen in inflammation can contribute to increased stacking of red blood cells causing higher ESR levels

Group O+ mother. Group A+ newborn with a 1+ positive DAT. Which investigative test would be most useful to resolve the cause of the positive DAT and should be done first?

Test newborns plasma cells against group A1 red cells and group O antibody screen cells by IAT The mother is group O RH positive with a negative antibody screen and the infant is group A RH positive. Results are consistent with a possible case of ABO HDFN. ABO HDFN is nearly always limited to A or B infants of group O mothers with potent anti-A,B

hyper acute transplant rejection

This rejection of an organ or tissue occurs within minutes after transplantation. The predominant mechanism is humor antibodies. The cause is preformed cytotoxic antibodies in the host to donor tissue cellular antigens. The antibodies are usually anti-A mediated for anti-B related antibodies to the ABO blood group systems or antibodies to class 1 MHC the antigens (hypersensitivity type 2)

A urine concentration test was performed on a patient after fluid deprivation with the following findings After 12 hours urine osmolality: 850 mOsm/Kg After 16 hours urine osmolality: 850 mOsm/Kg What does these results indicate?

This represents normal kidney function A urine osmolality of 800 or higher is considered normal when patients were deprived of fluid for 12 hours.

Leukocyte esterase test

This test detects inflammation, which indicates the presence of polymorphonuclear cells. These cells have granules that have leukocyte esterase activity

Nitrate reduction test

This test looks for the presence of urinary nitrate, which indicates that a urinary tract infection is present. Organisms most often associated with urinary tract infections can reduce nitrate to nitrite however, the nitrate reduction test may be negative, if the organisms reduce nitrate completely to nitrogen gas relax the enzyme to reduce nitrate. The Enterobacteriaceae Group is the group most often associated with UTIs and has nitrate reduction ability

The clot-based assay that is most specific for measuring for fibrinogen function is the:

Thrombin Time (TT)

Substances that can be used to induce platelet aggregation when performing platelet aggregation studies

Thrombin, ADP, Epinephrine, collagen, snake venom, ristocetin Plasminogen does not induce platelet aggregation. it is the precursor of plasmin which is the enzyme that breaks down fibrin clots

Chloroquine Diphosphate can be used in blood banking which of the following methodologies?

To remove antibody bound to read cells so that the cells can be further tested

Niacin test

Used for differentiating Mycobacteria species. All the mycobacteria species can be reduce niacin with the exception of Mycobacterium tuberculosis

India ink for fungi

Used to examine cerebral spinal fluid for the presence of cryptococcus neoformans, which exhibits an encapsulated appearance

Entero-test/string test

Uses a nylon cord inside a gelatin capsule that is swallowed. The cord is weighted and passes out of the stool where the mucus that is collected on the cord is examined for parasites

Which method may be used by a laboratory to document and analyze all of the steps that bring a laboratory test results to the customer

Value stream mapping Value stream mapping is a Lean process that can be used by laboratory personnel to document and analyze all of the steps that bring a laboratory test results to the customer.

What is the causative agent of plague?

Yersinia pestis

Lithium

anti-depressant