Media Lab Study Qs 5/1
mycobacterium abscessus
Several patients developed subcutaneous abscesses at the sites of injection of a preparation labeled "adrenal cortex injection" administered as part of a weight loss regimen. Pale-staining, filamentous acid-fast bacilli were seen in the material aspirated from the lesions (the upper photomicrograph is representative) and the colonies shown in the lower photograph grew out after 3 days incubation at 35°C in CO2. The most likely identification is:
flow cytometry
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:
HBeAg
The antigen marker most closely associated with transmission of HBV infections is:
over-centrifugation
Which of the following might cause a false positive indirect antiglobulin test (IAT)? Failure to adequately wash cells Delay in the addition of antiglobulin reagent Over centrifugation High concentration of IgG paraprotein in a patient's serum
The incidence of unexpected red blood cell antibodies is relatively low.
In an emergency release, why do blood bankers seldom encounter patients who have experienced hemolytic transfusion reactions (HTR) from transfusion of uncrossmatched packed RBCs? Select the best response. The incidence of unexpected red blood cell antibodies is relatively low. They usually receive group O Rh-negative red blood cells; a hemolytic transfusion reaction will never occur if O Rh-negative red blood cells are transfused. They hemorrhage so severely that incompatible donor red blood cells "bleed out" before a reaction occurs. Some patients have cold-reactive antibodies that will not react at body temperature.
high risk of severe sepsis/septic shock
A critically ill 86-year-old female was admitted to the intensive care unit (ICU) after arriving at the emergency department with symptoms that included shortness of breath and fever. Her temperature was 39°C (102°F) and pulse rate 110/minute. A white blood count (WBC) was ordered and was elevated at 15.0 x 109/L. The differential showed an increase in segmented and immature neutrophils. Other testing was ordered after admission to ICU, including a procalcitonin (PCT). The result was 2.15 ng/mL (Reference value for normal at the 95th percentile is <0.05 ng/mL). Given the clinical assessment and laboratory test results, what may the increased procalcitonin indicate?
Hgb A = 60%, Hgb S = 38%, Hgb A2 = 2%, Hgb F = 0% Patients with sickle cell trait commonly have Hgb A values between 40 and 60%, Hgb S values between 20 and 40% and Hgb A2 values between 2 and 3%.
A known sickle cell trait patient has a hemoglobin electrophoresis test performed. Which of the following hemoglobin percentage sets would most closely match this patient's diagnostic state?
one of the values is in error
A male patient's urea nitrogen value is 15 mg/dL and his creatinine is 5 mg/dL. If this patient is not undergoing dialysis, what conclusion would you draw from these results?
myoglobin
A patient is admitted to the hospital with acute chest pain, but which of the following cardiac markers will be elevated FIRST if the patient had a myocardial infarction (MI)? LD CK Myoglobin Troponin
post transfusion purpura
A patient is experiencing prolonged bleeding following a transfusion. The complete blood count indicates that the patient's platelet count has decreased following the transfusion. What is the most likely cause of this issue?
zero order
A reaction is in ____________ kinetics when the reaction rate depends only on enzyme concentration.
ELISA testing for Hepatitis A antigens in the stool
A traveler is being evaluated at a local hospital for gastrointestinal pain, fever, and diarrhea. The patient has recently returned from a month-long visit to Southeast Asia. The patient has no recent history of sexual activity or IV drug use but did describe conditions of poor sanitation where they were visiting. If liver function test results were elevated and bilirubinuria was noted, which of the following would be the next logical test to order? ELISA test for the Hepatitis B Surface Antigen (HBsAg) Recombinant Immunoblot Assay (RIBA) test for Hepatitis C Western Blot test for HIV ELISA testing for Hepatitis A antigens in the stool
The strength with which multivalent antigens and antibodies bind
Avidity is best described by which of the following statements?
pernicious anemia
Bence-Jones proteinuria is associated with all of the following conditions EXCEPT: Macroglobulinemia Pernicious anemia Multiple myeloma Amyloidosis
urea
What is the largest constituent of plasma nonprotein nitrogen:
Insulin dependent diabetes mellitus
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 3 months; she was always thirsty; drinking a lot of water and running to the bathroom. The following are her laboratory results: Results: (indicates reference range) pH: 7.11 (7.35-7.45)pCO2: 21 mm Hg (35-45 mm Hg)Glucose: 950 mg/dL (60-110 mg/dL)Serum osmolality: 365 mOsm/Kg (275-295 mOsm/Kg)Urine ketone: strongly positive (negative)Urine glucose: strongly positive (negative) What is the MOST likely cause of this patient's symptoms?
cushing's syndrome
A 64-year old man lost 15 pounds, became weaker, and his face became fuller with a ruddy complexion. His laboratory tests revealed: Serum cortisol8 AM: 880 nmol/L, 138-635 nmol/L (reference range)4 PM: 828 nmol/L, 83-414 nmol/L (reference range) After these results, an overnight dexamethasone suppression test gave a cortisol level of 773 nmol/L. The MOST probable diagnosis for this patient is:
uric acid, BUN, creatinine
A blood sample is left on a phlebotomy tray for four hours before it is delivered to the laboratory. Which group of tests could still be performed? (Glucose, Na, K, Cl, PCO2) (Uric acid, BUN, creatinine) (Total and direct bilirubin) (CK, ALT, ALP, ACP)
laboratory detection
An error is a verified and reported result on a patient that is later determined to be inaccurate. To identify an error, reports can be reviewed, other microbiologists may locate the error through testing, or nurses and physicians may come across the error when evaluating laboratory results. If an error is detected by repetitive quality control testing, which may indicate probable erroneous patient results, this is an example of which type of error detection?
T lymphocytes
Contact dermatitis is mediated by:
Histoplasma capsulatum
From the fungi listed below, which is considered to be a true pathogen that also infects immunocompromised patients? Scopulariopsis species Penicillium species Histoplasma capsulatum Fusarium species
-65C or lower
Frozen red cells that have been prepared with high glycerol methods (40% glycerol) can be stored up to 10 years if held at which of the following temperatures? - 65o C or lower - 20o C or lower - 10o C or lower 0o C or lower
acute infection
Given the following hepatitis B serology results, what is the immune status of the patient? HBsAg: positive HBeAg: positive Anti-HBc IgM: positive Anti-HBs: negative
increased cardiovascular risk
High levels of lipoprotein-associated phospholipase A2 (Lp-PLA2) are associated with:
homogenous or diffused staining pattern; systemic lupus erythematosus
Identify the antinuclear antibody (ANA) staining pattern in the image (a) and interpret what related disorder can be associated with this pattern?
multinucleate histiocyte
Identify the large multinucleated cell found in this cerebrospinal fluid cytospin field.
beta-galactoside permease
Orthonitrophenyl-b-D-galactopyranosidase (ONPG) is produced by several bacterial species. It acts by cleaving the beta galactosidase bond of certain disaccharides, such as lactose. An ONPG-positive bacterial species, however, may appear as a "late lactose user" because of the absence of what?
aureobasidium pullulans
Reports of verrucose skin and visceral infections with this black yeast have been reported. The bottom image illustrates the microscopic view as prepared in a mount prepared from the surface of the colony. Note the background dark-staining hyphae from which are produced small, elliptical conidia. Select from the choices below the correct presumptive identification of this isolate.
ESBL (Extended Spectrum Beta-Lactamase)
The Carba NP confirmatory test is used to detect all of the following carbapenemases EXCEPT? KPC (Klebsiella pneumoniae carbapenemase) NDM-1 (New Delhi metallo-beta-lactamase) VIM (Verona integron-encoded metallo-beta-lactamase) ESBL (Extended Spectrum Beta-Lactamase)
reverse transcriptase
The amplification of an RNA target through Reverse transcription PCR (RT-PCR) to detect HIV requires the following enzyme for the initial synthesis of DNA from the viral RNA template:
acute phase proteins are synthesized slowly in response to tissue injury
The characteristics of an acute phase protein include the following EXCEPT: An acute phase response is a non-specific indicator of an inflammatory response. Acute phase proteins are synthesized slowly in response to tissue injury. C-reactive protein is an acute phase protein. Laboratory measurement of an acute phase can be used to monitor the progress of therapy in inflammatory diseases
Porphyromonas asaccharolytica
The colonies illustrated in the composite blood agar/MacConkey agar to the left were recovered from an inflammatory infection of the oral cavity of a 16-year-old student. The colonies on both agar plates incubated anaerobically are small, entire, and smooth with a light gray-yellow pigmentation. Small gram-negative rods arranged singly and in loose clusters had been observed microscopically in a gram-stained preparation. Spot indole and lipase reactions are positive. Note in the image to the right the alk/alk non-fermentative carbohydrate reaction on Kligler Iron agar, with lack of fermentation of the sugars presented in the tubes to the right (asaccharolytic). Select from the multiple choices the name of this anaerobic, asaccharolytic, gram-negative isolate.
clinically insignificant cold antibodies
The immediate spin phase of an indirect antiglobulin test (antibody screen and antibody identification) could most likely lead to the detection of which of the following? Clinically significant warm antibodies Clinically significant cold antibodies Clinically insignificant warm antibodies Clinically insignificant cold antibodies
Recollect a specimen for a platelet count without using EDTA
What would be the next step when an EDTA specimen had an automated platelet count of 61,000/mm3 and the platelets were surrounding the neutrophils on the differential?
increased
When a patient is suspected of intoxication, what would you expect the osmol gap to be?
lyme disease
The positive predictive value of a Borrelia burgdorferi (B. burgdorferi) antibody assay depends on the likelihood of ____________ being present.
sample
The research team at the hospital selected 16 employees at random and tested their BUN levels. They found an average of 16 mg/dL with a standard deviation of 6.5 mg/dL. They used this data to construct a range of normal values for the whole healthy population. The underlined phrase is an example of what portion of the research study?
10-15 ml
The volume of urine recommended for centrifugation for a microscopic examination is:
Opsonization of antigens for phagocytosis by macrophages and neutrophils; neonatal immunity by transfer of maternal antibodies across the placenta and gut of the fetus.
Two biologically functional characteristics of immunoglobin G (IgG) are:
check for clerical errors in all steps of the pre- and post processes
What is the FIRST thing blood bank staff should do when investigating a transfusion reaction?
phototherapy
What is the most common treatment for hemolytic disease of the fetus and newborn (HDFN) due to ABO incompatibility?
the production of spores within sporangia
What is the most helpful feature in differentiating the Zygomycetes from the other hyaline molds in the clinical mycology laboratory?
the presence of round macrocytes in nonmegaloblastic anemia
When distinguishing megaloblastic from nonmegaloblastic macrocytic anemia, which of the following is a key difference in red blood cell morphology?
rabbit erythrocyte stroma (RESt)
Which adsorption technique removes cold (IgM) antibodies, particularly anti-I specificities?
cTnT
Which cardiac biomarker is a regulator of myocyte contraction?
T cells and macrophages
Which immune elements are involved in a POSITIVE TB skin test?
antithyroid peroxidase
Which of the following autoantibodies are found in a patient with Hashimotos thyroiditis?
protein s
Which one of the following is not an acute phase protein? Alpha-1 Antitrypsin C-Reactive Protein Protein S Fibrinogen
about 11% lower
Whole blood glucose values are ____________ plasma glucose values. about 40% higher about 11% lower about 80% lower equal to
Perform a clerical check, centrifuge the pre-transfusion and post-transfusion patient specimens and examine the plasma for hemolysis and icterus.
You receive a call in the blood bank, reporting a transfusion reaction. You ask the nurse to stop the red blood cell transfusion immediately and return the unit of blood and all related forms to the blood bank. You also ask for a new patient blood specimen to be drawn and sent to the blood bank. You receive the requested items 15 minutes later. What will you do FIRST as part of your investigation?
leucine crystals
Identify the urine sediment elements shown by the arrow:
decreased, increased, increased
In patients with suspected primary hypothyroidism associated with Hashimoto's thyroiditis, one would expect the following laboratory test results:T4 ___? TSH ___? TRH stimulation ___?
teardrop cells
What is the predominant abnormal erythrocyte morphology associated with idiopathic myelofibrosis?
check and correct for lipemia
What would be the logical first step to obtain correct values when the following results were obtained on an electronic particle counter in hematology for an alcoholic patient? WBC 6,500/cu. mmMCV 90.1 fLRBC 4,550,000/cu. mmMCH 39.6 pgHGB 18.0 g/dLMCHC 43.4%HCT 41.5%
Uses directly labeled fluorescent nucleotides or probes with reporter molecules that are indirectly detected by fluorescent antibodies or affinity molecules
Which of the following best describes the methodology for FISH?
antibody is IgG
Which of the following characteristics of hemolytic disease of the fetus and newborn (HDFN) is NOT different for ABO and Rh HDFN? Disease predicted in titers Anemia at birth Antibody is IgG Bilirubin at birth
Neutral red / lactose / bile salts and crystal violet
Which of the following choices represents the characteristic indicator, fermentable sugar(s), and bacteriostatic agent(s) that are present in MacConkey agar respectively?
hemolytic anemia
Which of the following is NOT a condition in which coarse basophilic stippling is typically found? anemias of abnormal hgb synthesis thalassemia lead poisoning hemolytic anemia
escherichia coli
Which of the following microorganisms is LEAST likely to produce a capsule or slime layer? Escherichia coli Klebsiella pneumoniae Streptococcus pneumoniae Pseudomonas aeruginosa
dark field microscopy
Which of the following microscopic techniques is best suited for direct examination of the infectious agent of syphilis? Light microscopy Phase-contrast microscopy Dark-field microscopy Electron microscopy
clostridium difficile
Which of the following organisms are gram-positive? neisseria gonorrhoeae brucella species clostridium difficile pseudomonas aeruginosa
unexplained bleeding from surgical site
Which of the following signs and symptoms may be associated with immediate transfusion reaction, but is NOT usually associated with delayed hemolytic transfusion reaction? Fever and chills Unexplained bleeding from surgical site Unexplained drop in hgb Transient jaundice
Gram positive cocci in pairs or chains, catalase negative, esculin positive, PYR positive, vancomycin intermediate, motile, yellow pigment: Enterococcus casseliflavus.
Which of the following statements reflect accurate identifications of Enterococcus species?
albumin
Which one of the following proteins in cerebrospinal fluid (CSF) is used to monitor the integrity of the blood-brain barrier?
Charged particles migrate toward the same charged electrode.
Which one of the following statements regarding factors that affect the mobility or rate of migration in electrophoresis is NOT correct? Charged particles migrate toward the same charged electrode. The velocity of migration is controlled by the net charge of the particle. The velocity of migration is controlled by the strength of the electric field. The velocity of migration is controlled by the electrophoretic temperature.
The albumin band is the first peak and the largest
Which statement about densitometric patterns for the five-zone protein electrophoresis is correct?
first order
Which type of kinetic reactions are reactions in which the enzyme is in excess and the substrate concentration is the limiting factor?
perform a fetal bleed screen
While working at a blood bank laboratory, you hear chimes over the hospital loudspeaker system announcing the birth of a baby. Thirty minutes later, you receive a cord blood specimen that you identify as O positive. You previously received the mother's specimen and she was O negative with a negative antibody screen. What is the next action?
