Infectious Labs Flashcards
What does CBC with diff include
RBC count
Hemoglobin
Hematocrit
WBC breakdown
Platelet count
Blood smear
What’s included with a WBC breakdown
Neutrophils
Lymphocytes
Monocytes
Eosinophils
Basophils
What does the WBC breakdown tell us
Total number of WBC in venous system
If the WBC breakdown increases, what is it indicative of?
Leukemia
Trauma
Stress
If the number of WBC in a diff decreases, what does it mean
Infection
Failure of marrow
Radiation therapy
What does ANC stand for
Absolute neutrophil count
What does ANC show
The risk of infection
Which patients will have low ANC
Oncology patients
What are some other components of blood
Water
Electrolytes
Proteins
Gases
Nutrients
Waste
What does water in the blood do
It is a carrying liquid
What do electrolytes in the blood do
Assist with cellular function (calcium helps with clot formation)
Maintains pH and membrane excitability
What do proteins in blood do
Buffer and maintain osmotic pressure
Also responsible for antibodies
What is the most important protein in the blood and why?
Albumin because it makes up the bulk of the plasma
What do gases in the blood do
Byproduct of HC03- buffer and it helps with protein breakdown
What do nutrients in the blood do?
Helps with tissue repair and cellular fuction
What does waste in the blood contain?
Protein catabolism
Energy/protein metabolism
RBC destruction
What are neutrophils
Polymorphonuclear leukocyte (PMN)
-Most numerous leukocyte
- type of granulocyte
Where are neutrophils made
Bone marrow (takes 7-14 days)
How long do neutrophils circulate
6 hours
What does the DNA of the neutrophil do?
Encases the pathogen and increases WBC affinity for the pathogen….
Will form a phagosome once FB is intracellular and breaks it down to create antigen
If there are a lot of young WBC… what does that mean for the patient
There is something causing the bone marrow to produce lots of WBC
What will a lot of young WBC look like on a CBC with diff
The left shift
What causes neutrophilia?
Stress
Infection
Myelocytic leukemia
Inflammatory disorder
Metabolic disorders
What causes neutropenia
Anemia
Overwhelming infection
Viral infection
Chemo
What are monocytes and what do they do
APC (more than neutrophils)
Phagocytize nectrotic debris
Circulate longer than neutrophils
What causes monocytosis
Chronic inflammation
Ulcerative colitis
Parasites
What causes monocytopenia
Anemia
Prednisone
When are eosinophils and basophils seen
During parasitic infections ( not with bacterial OR viral infections)
What do eosinophils do
Create immediate hypersensitivity and fight off extracellular parasites
What do basophils do
Similar to mast cells, they increase inflammation reaction ( contain histamines, heparin, seratonin)
What do lymphocytes do
Combat chronic bacteria and acute viral infections
What are the types of lymphocytes
T- cells
B-cells
NK cells
What causes lymphocytosis
Viral infections
Hepatitis
Multiple myeloma
Chronic bacterial infections
What causes lymphocytopenia
Leukemia
Sepsis
HIV
Covid
What does a blood smear show
Takes a close look at RBCs and WBCs to identify infection, congenital disease, and leukemia
When are blood smears done
Only when something unusual pops up (concern for leukemia)
What is ESR
Erythrocyte sediment rate
What is CRP
C- Reactive Protein
What’s does ESR/CRP show
Non-specific inflammatory markers
What is the pro/con of ESR
More accurate in long term diseases, takes longer to increase, but stays increased longer
What are the pros/cons of CRP
Acute phase reactant protein, indicates infection, and it’s faster than ESR
DM/HTN/smoking can all increase results
What is lactate indicative of
Tissue hypoxia with anaerobic metabolism instead of aerobic
What factors can influence lactate levels
Sepsis, exercise, and shock can all increase lactate levels
Leaving a tourniquet on too long while drawing blood will also increase
What can you not tell by just looking at increased lactate levels
Whether it’s local or systemic
What is type 1 lactate increase
Lactate had increased but it’s drug induced instead of hypoxia
Type 2 increased lactate
This is the classic one caused from seizures, shock, and local ischemia
What is type 3 increased lactate
Idiopathic
When are cultures drawn
When looking for infection (placed on different mediums for optimal conditions)
When are blood cultures drawn
Bacteremia identification (intermittent or transient)
How many cultures are needed and from where to identify bacteremia
2 from 2 different locations
How long does it take for a blood culture to result
24 hours UNLESS it’s anaerobic
When are urine cultures drawn
Checking for UTI or STDs
When do you take an STD urine culture
In the morning for “dirty” urine (30cc)
How to test urine for UTI
Need clean urine- collect midstream
What does a purple gram stain result indicate
Gram positive
When are viral cultures seen
Highest in early disease process
What is important when taking viral cultures
Medium culture is grown on
How long does it take a viral culture to result
3-7 days
How are viral cultures separated
Whether they have RNA or DNA makeup
When looking at a viral culture sample, how will you know if a virus is drug sensitive
It will have a no growth ring around it
