CM Flashcards

Question

A urine specimen with a pH of 9.0: Indicates metabolic acidosis Should be recollected May contain calcium oxalate crystals Is seen after drinking cranberry juice

Answer 1

Should be recollected A pH above 8.5 is associated with an improperly preserved specimen and indicates that a fresh specimen should be obtained to ensure the validity of the analysis.

Answer 2

Albumin accepts hydrogen ions from the indicator

Answer 3

All of the above Microalbuminuria The development of diabetic nephropathy leading to reduced glomerular filtration and eventual renal failure is a common occurrence in persons with both type 1 and type 2 diabetes mellitus. Onset of renal complications can first be predicted by detection of microalbuminuria, and the progression of renal disease can be prevented through better stabilization of blood glucose levels and control of hypertension. The presence of microalbuminuria is also associated with an increased risk of cardiovascular disease.

Answer 4

Check for newborn galactosuria

Answer 5

Biliary obstruction

Answer 6

Specimen older than 2 hours Possible bacterial contamination

Answer 7

Hypersthenuric

Answer 8

Lysis of yeast cells by acetic acid

Answer 9

Bacteria An increase in urinary WBCs is called pyuria and indicates the presence of an infection or inflammation in the genitourinary system.

Answer 10

Squamous epithelial cells

Answer 11

Hemosiderin granules Following episodes of hemoglobinuria (transfusion reactions, paroxysmal nocturnal hemoglobinuria, etc.), the RTE cells may contain the characteristic yellow-brown hemosiderin granules. The granules may also be seen free-floating in the urine sediment. Confirmation of the presence of hemosiderin is performed by staining the urine sediment with Prussian blue.

Answer 12

Contains cholesterol

Answer 13

Diabetes mellitus Yeast cells, primarily Candida albicans, are seen in the urine of diabetic patients, immunocompromised patients, and women with vaginal moniliasis. The acidic, glucose-containing urine of patients with diabetes provides an ideal medium for the growth of yeast.

Answer 14

Protein concentration Crystals are formed by the precipitation of urine solutes, including inorganic salts, organic compounds, and medications (iatrogenic compounds). Precipitation is subject to changes in temperature, solute concentration, and pH, which affect solubility.

Answer 15

Polarized light Examination under polarized light can frequently differentiate between fibers and casts. Fibers often polarize, whereas casts, other than fatty casts, do not polarize.

Answer 16

Interference contrast microscope Interference-contrast microscopy provides a three-dimensional image showing very fine structural detail by splitting the light ray so that the beams pass through different areas of the specimen.

Answer 17

Wegener granulomatosis

Answer 18

Uromodulin

Answer 19

Acute tubular necrosis

Answer 20

Microscopic hematuria Urine specimens from patients suspected of passing or being in the process of passing renal calculi are frequently received in the laboratory. The presence of microscopic hematuria resulting from irritation to the tissues by the moving calculus is the primary urinalysis finding.

Answer 21

Bananas Patients must be given explicit dietary instructions before collecting any sample to be tested for 5-HIAA, because serotonin is a major constituent of foods such as bananas, pineapples, and tomatoes. Medications, including phenothiazines and acetanilids, also interfere with results. Patients should be directed to withhold medications for 72 hours before specimen collection.

Answer 22

5-hour timed urine kept under refrigeration The D-xylose absorption test is used to distinguish pancreatic insufficiency from intestinal malabsorption. The test requires a blood sample taken 2 hours after oral administration of 25 g of D-xylose, and a 5-hour timed urine sample. D-xylose is absorbed without the aid of pancreatic enzymes, and is not metabolized by the liver. Therefore, deficient absorption (denoted by a plasma level < 25 mg/dL and urine excretion of < 4g/5hours) points to malabsorption syndrome.

Answer 23

Phenathridine The DNA within the cells is stained by the orange dye, phenathridine; the nuclear membranes, mitochondria, and negatively charged cell membranes are stained with a green dye, carbocyanine.

Answer 24

Carbocyanine The DNA within the cells is stained by the orange dye, phenathridine; the nuclear membranes, mitochondria, and negatively charged cell membranes are stained with a green dye, carbocyanine.

Answer 25

Impedance detection, forward light scatter and fluorescence The UF-100 and UF-50 use laser-based flow cytometry along with impedance detection, forward light scatter, and fluorescence to identify the individual characteristics and stained urine sediment particles in a flowing stream.

Answer 26

Small-particle histogram IRIS SLIDELESS MICROSCOPE Small particle histograms are graphic display of size distribution of f any small sediment particles (ranging from 1 to 6 um2) found during the microscopic examination. The histograms help to decide whether bacteria are present in these small ranges or if the detected particles are small crystals or amorphous.

Answer 27

Producing an ultrafiltrate of plasma

Answer 28

Hematology

Answer 29

A recent hemorrhage

Answer 30

Tubercular meningitis

Answer 31

Normal saline Dilutions for total cell counts are made with normal saline, mixed by inversion, and loaded into the hemocytometer with a Pasteur pipette.

Answer 32

Acetic acid Lysis of RBCs must be obtained before performing the WBC count on either diluted or undiluted specimens. Specimens requiring dilution can be diluted in the manner described previously, substituting 3% glacial acetic acid to lyse the RBCs. Adding methylene blue to the diluting fluid stains the WBCs, providing better differentiation between neutrophils and mononuclear cells.

Answer 33

Counted undiluted Clear specimens may be counted undiluted, provided no overlapping of cells is seen during the microscopic examination. When dilutions are required, calibrated automatic pipettes, not mouth pipetting, are used.

Answer 34

Increase cell yield and decrease cellular distortion As little as 0.1 mL of CSF combined with one drop of 30% albumin produces an adequate cell yield when processed with the cytocentrifuge. Adding albumin increases the cell yield and decreases the cellular distortion frequently seen on cytocentrifuged specimens.

Answer 35

Nucleated RBCs Neutrophils with pyknotic nuclei indicate degenerating cells. They may resemble nucleated red blood cells (NRBCs) but usually have multiple nuclei.

Answer 36

All of the above The purpose of macrophages in the CSF is to remove cellular debris and foreign objects such as RBCs. Macrophages appear within 2 to 4 hours after RBCs enter the CSF and are frequently seen following repeated taps. They tend to have more cytoplasm than monocytes in the peripheral blood (PB). The finding of increased macrophages indicates a previous hemorrhage.

Answer 37

Bone marrow contamination NRBCs are seen as a result of bone marrow contamination during the spinal tap. This is found in approximately 1% of specimens. Capillary structures and endothelial cells may be seen following a traumatic tap.

Answer 38

As a complication of acute leukemia

Answer 39

15 to 45 mg/dL Reference values for total CSF protein are usually listed as 15 to 45 mg/dL, but are somewhat method dependent, and higher values are found in infants and people over age 40. This value is reported in milligrams per deciliter and not grams per deciliter, as are plasma protein concentrations.

Answer 40

Fluid leakage

Answer 41

CSF/serum albumin index ALBUMIN INDEX An index value less than 9 represents an intact blood– brain barrier. The index increases relative to the amount of damage to the barrier.

Answer 42

Ammonia Reye syndrome Acute encephalopathy and liver infiltration seen in children following viral infections

Answer 43

Glutamine Determining CSF glutamine provides an indirect test for the presence of excess ammonia in the CSF. The normal concentration of glutamine in the CSF is 8 to 18 mg/dL.

Answer 44

Centrifuged The Gram stain is routinely performed on CSF from all suspected cases of meningitis, although its value lies in detecting bacterial and fungal organisms. All smears and cultures should be performed on concentrated specimens because often only a few organisms are present at the onset of the disease. The CSF should be centrifuged at 1500 g for 15 minutes, and slides and cultures should be prepared from the sediment. Use of the cytocentrifuge provides a highly concentrated specimen for Gram stains.

Answer 45

Cryptococcus neoformans

Answer 46

Prostate gland

Answer 47

Decreased sperm count When a part of the first portion of the ejaculate is missing, the sperm count will be decreased, the pH falsely increased, and the specimen will not liquefy. When part of the last portion of ejaculate is missing, the semen volume is decreased, the sperm count is falsely increased, the pH is falsely decreased, and the specimen will not clot.

Answer 48

Antispermicide in the condom Specimens should be collected by masturbation. If this is not possible, only nonlubricant-containing rubber or polyurethane condoms should be used. Ordinary condoms are not acceptable because they contain spermicides.

Answer 49

1 hour A fresh semen specimen is clotted and should liquefy within 30 to 60 minutes after collection; therefore, recording the time of collection is essential for evaluating semen liquefaction. Failure of liquefaction to occur within 60 minutes may be caused by a deficiency in prostatic enzymes and should be reported.

Answer 50

Decrease the viscosity Analysis of the specimen cannot begin until liquefaction (normal is within 30 to 60 minutes) has occurred. If after 2 hours the specimen has not liquified, an equal volume of physiologic Dulbecco’s phosphate-buffered saline or proteolytic enzymes such as alpha-chymotrypsin or bromelain may be added to induce liquefaction and allow the rest of the analysis to be performed.

Answer 51

Immobilize the sperm The most commonly used dilution is 1:20 prepared using a mechanical (positive-displacement) pipette. Dilution of the semen is essential because it immobilizes the sperm before counting. The traditional diluting fluid contains sodium bicarbonate and formalin, which immobilize and preserve the cells; however, good results can also be achieved using saline and distilled water.

Answer 52

Agree within 10% Using the Neubauer hemocytometer, sperm are usually counted in the four corner and center squares of the large center square, similar to a manual RBC count. Both sides of the hemocytometer are loaded and allowed to settle for 3 to 5 minutes; then they are counted, and the counts should agree within 10%. An average of the two counts is used in the calculation. If the counts do not agree, both the dilution and the counts are repeated.

Answer 53

Penetrate the ovum

Answer 54

Midpiece The midpiece is the thickest part of the tail because it is surrounded by a mitochondrial sheath that produces the energy required by the tail for motility.

Answer 55

Head Abnormalities in head morphology are associated with poor ovum penetration, whereas neckpiece, midpiece, and tail abnormalities affect motility.

Answer 56

Vitality Additional parameters in evaluating sperm morphology include measuring head, neck, and tail size; measuring acrosome size; and evaluating for the presence of vacuoles. Inclusion of these parameters is referred to as Kruger’s strict criteria. Strict criteria evaluation requires the use of a stage micrometer or morphometry. At present, evaluation of sperm morphology using strict criteria is not routinely performed in the clinical laboratory but is recommended by the WHO. Strict criteria evaluation is an integral part of assisted reproduction evaluations.

Answer 57

Leukocytes and spermatids Differentiation and enumeration of round cells (immature sperm and leukocytes) can also be made during the morphology examination. Peroxidase-positive granulocytes are the predominant form of leukocyte in semen and can be further differentiated from spermatogenic cells and lymphocytes using a peroxidase stain.

Answer 58

Eosin-nigrosin stain Decreased sperm vitality may be suspected when a specimen has a normal sperm concentration with markedly decreased motility. Sperm vitality should be assessed within 1 hour of ejaculation. Vitality is evaluated by mixing the specimen with an eosin-nigrosin stain, preparing a smear, and counting the number of dead cells in 100 sperm using a brightfield or phase-contrast microscope. Living cells are not infiltrated by the dye and remain bluish white, whereas dead cells stain red against the purple background. Normal vitality requires 50% or more living cells and should correspond to the previously evaluated motility.

Answer 59

Seminal fluid fructose Low sperm concentration may be caused by lack of the support medium produced in the seminal vesicles, which can be indicated by a low to absent fructose level in the semen.

Answer 60

Epididymis decreased neutral alpha-glucosidase, glycerophosphocholine, and L-carnitine suggest a disorder of the epididymis.

Answer 61

A possible rape On certain occasions, the laboratory may be called on to determine whether semen is actually present in a specimen. A primary example is in cases of alleged rape. Microscopically examining the specimen for the presence of sperm may be possible, with the best results being obtained by enhancing the specimen with xylene and examining under phase microscopy. Seminal fluid contains a high concentration of prostatic acid phosphatase, so detecting this enzyme can aid in determining the presence of semen in a specimen. A more specific method is the detection of seminal glycoprotein p30 (prostatic specific antigen [PSA]), which is present even in the absence of sperm. Further information can often be obtained by performing ABO blood grouping and DNA analysis on the specimen.

Answer 62

Centrifuged and reexamined A negative wet preparation is followed by specimen centrifugation for 10 minutes and examination of the sediment.

Answer 63

Egg white The word “synovial” comes from the Latin word for egg, ovum. Normal viscous synovial fluid resembles egg white.

Answer 64

Acetic acid Traditional WBC diluting fluid cannot be used because it contains acetic acid that causes the formation of mucin clots. Normal saline can be used as a diluent. If it is necessary to lyse the RBCs, hypotonic saline (0.3%) or saline that contains saponin is a suitable diluent. Methylene blue added to the normal saline stains the WBC nuclei, permitting separation of the RBCs and WBCs during counts performed on mixed specimens.

Answer 65

Calcium oxalate Calcium oxalate crystals in renal dialysis patients.

Answer 66

Wet preparation Fluid is examined as an unstained wet preparation. One drop of fluid is placed on a precleaned glass slide and cover slipped. The slide can be initially examined under low and high power using a regular light microscope. Crystals may be observed in Wright’s-stained smears; however, this should not replace the wet prep examination and the use of polarized and red-compensated polarized light for identification.

Answer 67

Glucose The most frequently requested test is the glucose determination, because markedly decreased glucose values indicate inflammatory (group II) or septic (group III) disorders.

Answer 68

To classify transudates and exudates Traditionally, a variety of laboratory tests have been used to differentiate between transudates and exudates, including appearance, total protein, lactic dehydrogenase, cell counts, and spontaneous clotting. However, the most reliable differentiation is usually obtained by determining the fluid: blood ratios for protein and lactic dehydrogenase

Answer 69

Decreased mesothelial cells

Answer 70

Esophageal rupture A pH value as low as 6.0 indicates an esophageal rupture that is allowing the influx of gastric fluid. Pleural fluid pH lower than 7.2 may indicate the need for chest-tube drainage, in addition to administration of antibiotics in cases of pneumonia. In cases of acidosis, the pleural fluid pH should be compared with the blood pH. Pleural fluid pH at least 0.30 degrees lower than the blood pH is considered significant.

Answer 71

Tuberculosis infection

Answer 72

Serum ascites albumin gradient Differentiation between ascitic fluid transudates and exudates is more difficult than for pleural and pericardial effusions. The serum-ascites albumin gradient (SAAG) is recommended over the fluid:serum total protein and LD ratios to detect transudates of hepatic origin.

Answer 73

Absolute neutrophil count Normal PERITONEAL FLUID WBC counts are less than 350 cells/μL, and the count increases with bacterial peritonitis and cirrhosis. To distinguish between those two conditions, an absolute neutrophil count should be performed. An absolute neutrophil count >250 cells/μL or >50% of the total WBC count indicates infection.

Answer 74

Cirrhosis Hepatic disorders such as cirrhosis are frequent causes of ascitic transudates. Bacterial infections (peritonitis)—often as a result of intestinal perforation or a ruptured appendix—and malignancy are the most frequent causes of exudative fluids.

Answer 75

Ovarian cancer

Answer 76

Fetal urine

Answer 77

Delivered on ice and refrigerated Fluid for fetal lung maturity (FLM) tests should be placed in ice for delivery o the laboratory and kept refrigerated. Specimens for bilirubin testing must be immediately protected from light. This can be accomplished by placing the specimens in amber-colored tubes, wrapping the collection tube in foil, or by use of a black plastic cover for the specimen container. Specimens for cytogenetic studies or microbial studies must be processed aseptically and maintained at room temperature or body temperature (37°C incubation) prior to analysis to prolong the life of the cells needed for analysis.

Answer 78

To prolong fetal cell viability and integrity Specimens for cytogenetic studies or microbial studies must be processed aseptically and maintained at room temperature or body temperature (37°C incubation) prior to analysis to prolong the life of the cells needed for analysis.

Answer 79

Moderately affected fetus that requires close monitoring Notice that the Liley graph plots the A450 against gestational age and is divided into three zones that represent the extent of hemolytic severity. Values falling in zone I indicate no more than a mildly affected fetus; those in zone II indicate moderate hemolysis and require careful monitoring anticipating an early delivery or exchange transfusion upon delivery, whereas a value in zone III indicates severe hemolysis and suggests a severely affected fetus. Intervention through induction of labor or intrauterine exchange transfusion must be considered when a D A450 is plotted in zone III.

Answer 80

AFP levels Increased levels of alpha-fetoprotein (AFP) in both the maternal circulation and the amniotic fluid can be indicative of fetal neural tube defects, such as anencephaly and spina bifida.

Answer 81

Family history of chromosome abnormalities, such as trisomy 21 (Down syndrome) Earlier pregnancy or child with birth defect Elevated maternal serum alpha-fetoprotein Abnormal triple marker screening test

Answer 82

Fetal lung maturity HDN caused by Rh blood type incompatibility

Answer 83

Lecithin twice as concentrated as sphingomyelin The L/S ratio will rise to 2.0 or higher as the lecithin production increases to prevent alveolar collapse.

Answer 84

Aminostat-FLM AMNIOSTAT FLM: IMMUNOLOGIC AGGLUTINATION TEST FOR PHOSPHATIDYLGLYCEROL

Answer 85

The mother has maternal diabetes The presence of another lung surface lipid, phosphatidyl glycerol (PG), is also essential for adequate lung maturity and can be detected after 35 weeks’ gestation. The production of PG normally parallels that of lecithin, but its production is delayed in cases of maternal diabetes. In this circumstance, respiratory distress occurs in the presence of an L/S ratio of 2.0. Therefore, a thin-layer chromatography lung profile must include lecithin, sphingomyelin, and PG to provide an accurate measurement of FLM.

Answer 86

Lamellar bodies The presence of lamellar bodies increases the OD of the amniotic fluid. Specimens are centrifuged at 2000 g for 10 minutes and examined using a wavelength of 650 nm.

Answer 87

OD at 650 nm of 0.150 and an L/S ratio of 2.0 The number of lamellar bodies present in the amniotic fluid correlates with the amount of phospholipid present in the fetal lungs. The presence of lamellar bodies increases the OD of the amniotic fluid. Specimens are centrifuged at 2000 g for 10 minutes and examined using a wavelength of 650 nm, which rules out interference from hemoglobin but not other contaminants, such as meconium. An OD of 0.150 has been shown to correlate well with an L/S ratio of greater than or equal to 2.0 and the presence of phosphatidyl glycerol. A consensus protocol for noncentrifuged samples considers LBCs greater than 50,000/uL an indication of FLM and values below 15,000/uL as immature.

Answer 88

Blood The normal fecal specimen contains bacteria, cellulose, undigested foodstuffs, GI secretions, bile pigments, cells from the intestinal walls, electrolytes, and water.

Answer 89

Intestinal constriction

Answer 90

Quantitative fecal fat testing Quantitative fecal analysis requires the collection of at least a 3-day specimen. The patient must maintain a regulated intake of fat (100 g/d) before and during the collection period.

Answer 91

Fetal hemoglobin is present In the presence of alkali-resistant fetal hemoglobin, the solution remains pink (HbF), whereas denaturation of the maternal hemoglobin (HbA) produces a yellow-brown supernatant after standing for 2 minutes.

Answer 92

Cystic fibrosis

Answer 93

Positive Clinitest Normal stool pH is between 7 and 8; however, increased use of carbohydrates by intestinal bacterial fermentation increases the lactic acid level and lowers the pH to below 5.5 in cases of carbohydrate disorders

Answer 94

Two samples taken from different parts of three stools Two samples from three different stools should be tested before a negative result is confirmed.

Answer 95

Bacterial vaginosis Amine (Whiff) Test 1. Apply one drop of the saline vaginal fluid suspension to the surface of a clean glass slide. 2. Add one drop of 10% KOH directly to the vaginal sample. 3. Holding the slide in one hand, gently fan above the surface of the slide with the other hand and assess for the presence of a fishy amine odor. 4. Report as positive or negative. Positive: The presence of a fishy odor after adding KOH. Negative: The absence of a fishy odor after adding KOH.

Answer 96

Preterm delivery The presence of fetal fibronectin in vaginal secretions between 24 and 34 weeks’ gestation is associated with preterm delivery.

Answer 97

6. What two technologies are used for urine sediment analysis? A. Light scattering and refractometry B. Light scattering and flow cytometry C. Flow cytometry and digital imaging⭐️ D. Digital imaging and refractometry 7. Which automated urine particle counter combines urine flow cytometry with digital image analysis? A. UN-2000⭐️ B. iRICELL C. UF-100i D. iQ 200 8. Which of the following urine sediment particles cannot be autovalidated but will be flagged and must be reviewed by laboratory personnel? A. RBCs B. WBCs C. RTEs⭐️ D. Squamous epithelial cells 9. Which of the automated body fluid analyzers does not need to dilute or pretreat body fluids before analysis? A. ADVIA 2120i B. XN Series⭐️ C. iQ200 D. None of the above 10. What is a disadvantage of counting body fluid cells using an automated instrument versus a Neubauer hemocytometer? A. Less labor-intensive and time-consuming B. More precise C. Unable to count low WBC numbers and malignant cells⭐️ D. Able to perform a WBC differential Correct answer is letter C: Body fluids with low cell counts or malignant cells still require a manual differential using a stained cytospin smear.

CM Flashcards

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