Question 1

The __________ stain incorporates the substrate alpha-naphthol butyrate coupled with the diazo salt for staining of macrophages.

Accepted Answer

The staining method described is the Nonspecific esterase stain, which is used to identify macrophages. The substrate used in this stain is alpha-naphthol butyrate, and it is coupled with a diazo salt. The other stains mentioned (peroxidase, specific esterase, and PAS) do not use this substrate or method for identifying macrophages.

Question 2

What is the specimen of choice for the specific esterase (naphthol AS-D chloroacetate) stain?

Accepted Answer

Fresh capillary blood is the specimen of choice for the specific esterase stain using naphthol AS-D chloroacetate. Oxalated, heparinized, and EDTA-anticoagulated blood may interfere with the stain and affect the accuracy of the results.

Question 3

Terminal deoxynucleotidyl transferase (TdT) is an enzyme marker for primitive __________ cells.

Accepted Answer

Terminal deoxynucleotidyl transferase (TdT) is an enzyme marker that is commonly used to identify lymphoid cells, specifically the immature or primitive ones. TdT is expressed during the early stages of B and T cell development and is involved in the insertion of nucleotides into DNA during V(D)J recombination, a process that generates the diversity of antigen receptor genes in lymphocytes. TdT is not specific to myeloid or megakaryocytoid cells.

Question 4

Esterase is inhibited by __________.

Accepted Answer

Esterase is inhibited by mercury, acid solutions, heat, and iodine, making all of the options correct.

Question 5

Which specimen requirements apply to the TdT test?

Accepted Answer

The TdT test, which is used to detect terminal deoxynucleotidyl transferase in cells, requires specific specimen conditions for accurate results. These include using a nonheparinized bone marrow aspirate to prevent anticoagulant interference with the assay, separated marrow cells that are washed with culture media to ensure purity and viability of the cells for testing, and storing slides at 4°C in the dark to preserve the integrity of the samples until analysis.

Question 6

Isoenzyme 5, the acid phosphatase fraction found in hairy cell leukemia, is __________ to the addition of tartaric acid.

Accepted Answer

Isoenzyme 5, the acid phosphatase fraction found in hairy cell leukemia, is resistant to the addition of tartaric acid. This is a characteristic feature used in the diagnosis of hairy cell leukemia.

Question 7

What is the principle of the specific esterase (naphthol AS-D chloroacetate) stain?

Accepted Answer

The specific esterase (naphthol AS-D chloroacetate) stain works on the principle that the esterase enzyme within the cell hydrolyzes the substrate (naphthol AS-D chloroacetate), which then couples with a diazo salt to form a colored compound, indicating the presence of esterase activity. This is a common technique used in histology and hematology to identify and classify different types of cells, especially leukocytes.

Question 8

The staining pattern in the PAS reaction may be __________.

Accepted Answer

The staining pattern in the PAS reaction can be granular, diffuse, or block depending on the type of tissue or substance being stained. Therefore, option D (all of the above) is the best choice.

Question 9

Material that stains PAS positive appears __________.

Accepted Answer

Material that stains PAS (Periodic Acid-Schiff) positive appears bright red. This staining technique is commonly used to highlight structures containing a high concentration of carbohydrate macromolecules, such as glycogen, glycoproteins, and proteoglycans.

Question 10

This esterase staining procedure utilizes both alpha-naphthol butyrate and naphthol AS-D chloroacetate as substrates.

Accepted Answer

This staining procedure is a combined esterase staining, as it uses two different substrates to stain for a variety of esterases. The use of both alpha-naphthol butyrate and naphthol AS-D chloroacetate allows for the differentiation of different types of esterases based on their substrate specificity, and therefore provides a more comprehensive view of esterase activity.

Question 11

Which constitutes a positive result with the acid phosphatase/tartrate resistant stain?

Accepted Answer

A positive result with the acid phosphatase/tartrate resistant stain is indicated by the presence of two or more cells with a 4+ activity showing an orange-red precipitate. Option A describes a bluish-black precipitate, which is not indicative of a positive result with this stain. Option C describes >5 cells, but does not specify the color of the precipitate, and option D describes a bluish-black precipitate again which is not indicative of a positive result. Therefore, option B is the best choice as it describes the appropriate number of cells and the correct color of the precipitate for a positive result.

Question 12

PAS stains __________ in the cell.

Accepted Answer

PAS (Periodic Acid-Schiff) stains glycogen in the cell. It does not stain lipids, mitochondria, or proteins.

Question 13

The acid phosphatase/tartrate resistant stain is used for making diagnosis of:

Accepted Answer

The acid phosphatase/tartrate resistant stain is used to confirm the diagnosis of hairy cell leukemia, as it is typically positive in most cases of the disease. It is not a specific test for any of the other options listed.

Question 14

The purpose of the positive nonspecific esterase reaction which can be inhibited by the addition of sodium fluoride is to aid in differentiation of French-American-British (FAB) subclasses__________ and _____________.

Accepted Answer

The positive nonspecific esterase reaction that can be inhibited by sodium fluoride is used to differentiate between the French-American-British (FAB) subclasses M4 and M5, which are types of myelomonocytic and monocytic leukemias, respectively. This test helps in distinguishing these subclasses from other types of leukemia by identifying the presence of specific esterase activity in the cells.

Question 15

In the combined esterase staining procedure, a dark, brown-red staining indicates:

Accepted Answer

The answer of In the combined esterase staining procedure, a...

Question 16

____________ percent of patients in CML blast crisis exhibit positive TdT activity.

Accepted Answer

The answer of ____________ percent of patients in CML blast...

Question 17

What is the principle of the TdT test?

Accepted Answer

The principle of the TdT test involves using a FITC-labeled antirabbit antibody that will bind to TdT in the nucleus of cells. If the cells contain TdT, they will fluoresce when exposed to a specific wavelength of light. This is the basis of the TdT test, which is commonly used in flow cytometry to identify lymphoid cells that are actively synthesizing DNA. Choices A and B are incorrect because they describe different tests that do not involve TdT.

Question 18

__________ percent of patients with acute undifferentiated leukemia will have positive TdT activity.

Accepted Answer

TdT is a marker for early lymphoid cells. In acute undifferentiated leukemia, the blasts are usually lymphoid and therefore TdT positive.

Quiz 36: Special Stainscytochemistry