CLIN MICROSCOPY LRH

equipment and other soiled inanimate objects, called ____ will serve as reservoirs, particularly if they contain blood, urine, or other body fluids.

FOMITES

The host ingests a contaminated substance eg. food, water specimen

vehicle

Host INHALES DRIED AEROSOLS

Host INHALES AEROSOL DROPLETS

Airborne

Droplets

Methos to break the chain of infection

Hand sanitizing ang adhering to standard precautions

In clinical laboratory the most direct contact with a source of infection is through

Contact with patient samples

HICPAC

Health Infection Control Practices Advisory Committee

Combined the major guidelines of UP and BSI called Standard Precautions

CDC and HICPAC Health Infection Control Practices Advisory Committee

Delayed hypersensitivity reactions resembling posion ivy that appear 24 to 48 hours after exposure

Allergy to latex gloves

When specimens are received in containers contaminated exteriors, the exterior should

must be disinfected or if necessary, a new specimen may be requested

Sodium hypochlorite dilutions stored in PLASTIC BOTTLES are effective for

1 month if protected from light

EMPTY URINE CONTAINERS can be discarded in

NONBIOLOGICALLY hazardous waste

Requires that all employees have a ___ about all chemical hazards present in their workplace

RIGHT TO KNOW

All electrical equipment must be grounded with

THREE-PRONGED PLUGS

requires that all health care facilities post evacuation routes and detailed plans to follow in the event of fire

The Joint Commission TJC

Organic peroxides are under

flame sign and exploding bombs

Overall process of guaranteeing quality patient care and it is regulated through the TOTAL TESTING SYSTEM.

Quality Management

All of the laboratory’s policies, process, procedures, and resources needed to achieve quality testing. includes not only test ing controls, referred to as quality control (QC), but also encompasses preexamination (preanalytical) variables (e.g., specimen collection, handling, and storage), examination (an alytical) variables (e.g., reagent and test performance, instru ment calibration and maintenance, personnel requirements, and technical competence),postexamination (postanalytical) variables (e.g., reporting of results and interpretation), and documentation that the program is being followed meticu lously.

Quality management system

provides the guidelines for writing these procedures and policies

Clinical and Laboratory Standards Institute (CLSI)

urine specimens should be examined

within 2 hours.

used as a tool to document a problem at the point of discovery, describing what happened and the immediate corrective action taken.

internal laboratory quality improvement form

This enables the laboratory director to capture the information to determine the root cause analysis (RCA) and develop a preventive or corrective action plan.

internal laboratory quality improvement form

Calibration of centrifuges and accuracy of timers are customarily per formed every:

every 3 months, and there should be a record of the appropriate relative centrifugal force for each setting.

External Quality Assessment aka

Proficiency Testing

testing of unknown specimens received from an outside agency and provides unbiased validation of the quality of patient test results.

External Quality Assessment

mandates comparison testing for laboratory accreditation.

Clinical Laboratory Improvement Amendments (CLIA)

an alternative CLIA QC option that provides equivalent quality testing to meet the CLIA regulations for moderate- and high complexity tests and provider-performed microscopy procedures (PPMP) tests.

Individualized Quality Control Plan

With this option, the laboratory can deter mine the frequency of QC testing based on information about the test, the risk assessment, and the accreditation agencies’ requirements.

Individualized Quality Control Plan

requires risk assessment (RA), a quality control plan (QCP), and quality assessment (QA)

Individualized Quality Control Plan

identifies and evaluates potential problems that may occur in the entire testing process from preexamination through the examination and post examination processes.

risk assessment (RA),

establishes control procedures to reduce the possibility of reporting an inaccurate patient test result. It must include the number, type, and frequency of testing, as well as criteria for acceptable results of the QCs

quality control plan (QCP)

now the most common method for reporting results.

Electronic transmission/Electronic Result

an automated comparison of patient results with predetermined preapproved criteria, programmed into them

autoverification

(the lowest level of an analyte that a test can detect)

sensitivity

(the likelihood of measuring the analyte desired)

Specificity

Reporting Critical Results In Urinalysis

Time of telephone call

Initials of the person making the call

Name of the person receiving the telephone call

international effort to standardize both the classification of hazardous chemicals and the symbols used to communicate these hazards on labels and in SDS documentation

Globally Harmonized System (GHS)

Globally Harmonized System (GHS) standard label elements include

GHS hazard pictograms

signal words\

GHS hazard statement

Two levels of commercial controls are available for

osmometer, urine reagent strip tests, and human chorionic gonadotropin (hCG) kit tests

Temperatures of refrigerators and water baths should be taken

daily and recorded.

Calibration of centrifuges and accuracy of timers are customarily per formed every

3 months, and there should be a record of the appropriate relative centrifugal force for each setting.

Disinfection of centrifuges should be done routinely on a

weekly basis or after spills

Microscopes should be kept clean at all times and have an

annual professional cleaning

Automatic pipettes are ____ and ____ checked for accuracy and reproducibility.

initially and periodically

Deionized water used for reagent preparation is quality controlled by checking

pH and purity meter resistance on a weekly basis, bacterial count on a monthly schedule.

verify the accuracy (ability to obtain the expected result) and precision (ability to obtain the same result on the same specimen) of a test, and they are exposed to the same conditions as the patient specimens.

External Quality Control

ability to maintain both precision and accuracy

Reliability

Documentation of QC includes:

dating and initialing the material when it is first opened and recording the manufacturer’s lot number and the expiration date each time a control is tested and the test result is obtained.

Personnel assessment includes

education and training, continuing education, competency assessment, and performance appraisals. Each new employee must have documentation of training during orientation to the laboratory. This is a check list of procedures and must include the date and initials of the person doing the training and of the employee being trained. Up-to-date reference materials and atlases should be readily available, and documentation of continuing education must be maintained.

References to the study of urine can be found in the drawings of cavemen and in Egyptian hieroglyphics, such as the

Edwin Smith Surgical Papyrus

wrote a book on “uroscopy.”

Hippocrates

albuminuria by boiling urine

Frederik Dekkers’s

These charlatans, called “pisse prophets,” became the subject of a book published by

Thomas Bryant

examination of urinary sediment and to the development by

Thomas Addis of methods

introduced the concept of urinalysis

Richard Bright

nephron by the following renal functions:

Renal blood flow

Glomerular filtration

Tubular reabsorption

Tubular secretion

nephrons in Each kidney contains approximately

approximately 1 to 1.5 million functional units

human kidney contains two types of nephrons.

Cortical nephrons

Juxtamedullary nephrons

responsible primarily for removal of waste products and reabsorption of nutrients.

Cortical nephrons

primary function is concentration of the urine.

Juxtamedullary nephrons

have longer loops of Henle that extend deep into the medulla of the kidney

Juxtamedullary nephrons

supplies blood to the kidney

renal artery

human kidneys receive____ of the blood pumped through the heart at all times.

approximately 25%

located adjacent to the ascending and descending loops of Henle in juxtamedullary nephrons.

vasa recta

major exchanges of water and salts take place between the blood and the medullary interstitium. This exchange main tains the osmotic gradient (salt concentration) in the medulla, which is necessary for renal concentration.

vasa recta

total renal blood flow is approximately

1200 mL/min,

total renal plasma flow ranges from

600 to 700 mL/min.

several factors influence the actual filtration process.

cellular structure of the capillary walls and Bowman capsule,

hydrostatic pressure and oncotic pressure

feedback mechanisms of the renin–angiotensin–aldosterone system (RAAS).

glomerulus is located within

Bowman capsule,which forms the beginning of the renal tubule.

nonselective filter of plasma substances with molecular weights less than 70,000,

glomerulus

glomerulus consists of a coil of approximately

eight capillary lobes, the walls of which are referred to as the glomerular filtration barrier.

enzyme produced by the juxtaglomerular cells, is secreted and reacts with the bloodborne substrate angiotensinogen to produce the inert hormone angiotensin I

Renin

As angiotensin I passes through the alveoli of the lungs, what enzyme is used to convert it to angiotensin II

angiotensin-converting enzyme (ACE) changes it to the active form angiotensin II.

Angiotensin II corrects renal blood flow in the following ways:

1. Dilates the afferent arteriole and constricts the efferent arteriole

2. Stimulates sodium reabsorption in the proximal convoluted tubule

3. Triggers the adrenal cortex to release the sodium-retaining hor mone aldosterone to cause sodium reabsorption and potassium excretion in the distal convoluted tubule and collecting duct

4. Triggers the hypothalamus to release antidiuretic hormone to stimulate water reabsorption in the collecting duct

As a result of the glomerular mechanisms, every minute, approximately

2 to 3 million glomeruli filter approximately 120 mL of water-containing low-molecular-weight substances.

Because this filtration is nonselective, the only difference between the compositions of the filtrate and the plasma is the

absence of plasma protein, any protein-bound substances, and cells.

Analysis of the fluid as it leaves the glomerulus shows the filtrate to have a specific gravity of

1.010 and confirms that it is chemically an ultrafiltrate of plasma.

2 to 3 million glomeruli filter

approximately 120 mL of water-containing low-molecular-weight substances.

Active transport

Glucose, amino acids, salts Chloride, Sodium

Passive transport

Water Urea Sodium

Glucose, amino acids, salts

Proximal convo luted tubule

Chloride

Ascending loop of Henle

Sodium

Proximal and distal convoluted tubules

Water

Proximal convo luted tubule

Descending loop of Henle

Collecting duct

Urea

Proximal convo luted tubule

Ascending loop of Henle

Sodium

Ascending loop of Henle

Movement of molecules across a membrane as a result of differences in their concentration or electrical potential on opposite sides of the membrane. These physical differences are called gradients.

Passive transport

Influenced by the concentration of the substance being transported. When the plasma concentration of a substance that is normally completely reabsorbed reaches a level that is abnormally high, the filtrate concentration exceeds the

maximal reabsorptive capacity (Tm) of the tubules, substance begins appearing ing in the urine.

plasma concentration at which active transport stops is termed the

renal threshold

Glucose appearing in the urine of a person with a normal blood glucose level is the result

tubular damage and not diabetes mellitus

major site for removal of these nonfiltered substances

proximal convoluted tubule.

creatinine, beta2-microglobulin (B2M), cystatin C, and, possibly, radioisotopes

primary substances used in clearance tests.

earliest glomerular filtration tests measured urea because of its presence in all urine specimens, as well as the existence of routinely used methods of chemical analysis.

Urea Clearance

a polymer of fructose, is an extremely stable sub stance that is neither reabsorbed nor secreted by the tubules. It is not a normal body constituent, however, and must be infused by IV at a constant rate throughout the testing period. Therefore, although inulin was the original reference method for clearance tests, current methods are available that are endogenous and can provide accurate GFR results.

Inulin Clearance

A test that requires an infused substance is termed an exogenous procedure and is seldom the method of choice if a suitable test substance is already present in the body (endogenous procedure)

Inulin Clearance

a waste product of muscle metabolism that is produced enzymatically by creatine phosphokinase from creatine, which links with adenosine triphosphate (ATP) to produce adenosine diphosphate (ADP) and energy. Because creatinine is normally found at a relatively constant level in the blood, it provides the laboratory with an endogenous procedure for evaluating glomerular function.

Creatinine Clearance

shown to be a good procedure for screening and monitoring GFR.

cystatin C

small protein (molecular weight 13,359) produced at a constant rate by all nucleated cells.

cystatin C

It is filtered readily by the glomerulus and reabsorbed and broken down by the renal tubular cells.

cystatin C. therefore, no cystatin C is secreted by the tubules, and the serum concentration can be related directly to the GFR.

recommended for pediatric patients, people with diabetes, the elderly, and patients who are critically ill.6 An advantage is that it is independent of muscle mass.

cystatin C

dissociates from human leukocyte antigens at a constant rate and is removed rapidly from the plasma by glomerular filtration.

Beta2-Microglobulin