How to Collect Specimen
and Testing Method –
Nurses Guide
Collection of Urine Specimen:
Method of Collecting Single Urine Specimen
Single urine specimen means the amount of urine voided at a time. Usually the morning specimens are collected. An amount of 100 to 120 ml of urine will be sufficient for the usual tests.
After cleaning the genital area, the client passes urine into clean urinal or a clean kidney tray or directly into the specimen bottle, taking care not to spill the urine on the outside of the container.
Method of Collecting Midstream Specimen for Culture
Ask the client to clean the genital area with soap and water, then rinse with water alone. In female clients, the labia are separated for cleaning and kept apart until the urine had been collected. In male clients, the foreskin should be retracted and the glans penis is cleaned before the collection of the urine.
The client begins to void into the toilet, commode or bed pan. Then the client stops the stream of urine, the sterile container is positioned and continues to void into the container. When enough urine had been voided, for specimen, the client stops the stream again, the container is removed and then finishes voiding in the original receptacle.
By this method, the first stream of urine flushes out the organisms and mucus usually present at the meatus, so that accurate result can be obtained.
Catheterization may be necessary to get specimens from unconscious client or menstruating clients. As far as possible the catheterization is avoided as it may cause urinary infection due to the introduction of microorganisms along with the catheter into the urinary tract or it may cause tissue trauma.
Method of Collecting 24 Hours Urine Specimen
Twenty-four hours urine specimen means to collect all the urine voided in 24 hours. The collection of urine begins at 6 A.M. Ask the client to void at 6 A.M. and discard the whole urine. All the subsequent voiding should be measured and collected in the bottle which is labeled. Continue to collect till next morning. Ask the client to void at 6 A.M. and discard the whole urine. All the subsequent voiding should be measured and collected in the bottle which is labeled. Continue to collect till next morning. Ask the client to void at 6 A.M. on the next day and add it to the urine previously collected.
It is necessary to add preservatives to the urine to prevent decomposition and multiplication of bacteria. A variety of preservatives are available such as toluene, boric acid concentrated hydrochloric acid, formalin, chloroform etc.
Method of Collecting Urine Specimen from Unconscious Clients and Children
To collect urine from male babies or unconscious male clients, take a test tube, a barrel of a syringe or with rubber tubing and is attached to the penis. It is kept in place by adhesive tapes. The rubber tubing is connected to a bottle and the urine is collected in the bottle.
To collect the urine from the female clients, attach a wide mouthed container or a funnel with a rubber tubing to the vulva by means of a “T” binder. The rubber tubing is connected to a bottle and the urine is collected in the bottle.
Examination of the Urine
Characteristics of Normal Urine
Volume – 1000 to 2000 ml is excreted in 24 hours.
Color – Normal urine is pale yellowish or amber in color. When the quantity of urine is increased, the color becomes pale yellow and when the quantity of urine is decreased, the color becomes deep yellow.
Appearance – the normal urine has an aromatic odour.
Reaction – It’s slightly acidic (pH below 7).
Specific Gravity – the specific gravity of urine varies from 1.016 to 1.025, with a normal fluid make. Specific gravity of the urine varies due to the substances dissolved in the urine.
Constituents of Urine
The normal constituents of urine are water 96%, urea 2% and the remaining 2 % consists of uric acid, urates, creatinine, chlorides, phosphates, sulphates and oxalates. Uric acid and urates are formed from the tissue breakdown. Chlorides are formed from the sodium chloride intake in the diet. Oxalates, phosphates and sulphates are derived from the vegetable food.
Characteristics of Abnormal Urine
Volume – abnormal increase in the volume is known as “polyuria” , and is found in diabetes mellitus and diabetes insipidus. Decreased quantity of urine is called “oliguria” and is found in heart diseases, kidney diseases and in shock conditions. Total absence or marked decrease of urine is known as “anuria”. Failure of the kidney to secrete urine is known as suppression.
Color
Green or brownish yellow – bile salts and bile pigments.
Reddish brown – urobilinogen
Bright red – a large amount of fresh blood
Pink – a small amount of fresh blood
Smoky brown – blood pigments
Milky white – chyluria due to filariasis
Odour
Sweetish or fruity odour is due to the presence of ketone bodies (acetone and diacetic acid) seen in diabetic clients.
Appearance
Cloudy appearance is due to the presence of amorphous phosphates. This disappears with the dilution of acetic acid. Amorphous urates give a cloudy appearance to the urine and will disappear on heating. Turbidity of urine is due to the presence of pus which clears on filtering. Deposits are due to the presence of various substances:
Mucus – appear as a flocculent cloud.
Pus – settles at the bottom as a heavy cloud.
Stones – as fine sand.
Uric acid – as grains of pepper.
Reaction
When there is cystitis, the reaction of the urine may be alkaline. Precaution is to be taken to collect fresh urine specimen for reaction. On standing at room temperature, the urine becomes alkaline due to the formation of ammonia.
Specific Gravity
In disease the specific gravity may range from 1.001 to 1.060. it may be high in diabetes mellitus due to the presence of sugar and it may be low in renal diseases due to the inability of the kidneys to concentrate the urine.
Constituents of Urine
Albumin is present when there is kidney damage. Presence of albumen in the urine is termed as “albuminuria”. Sugar in the urine indicates diabetes mellitus. In pregnancy, when the renal threshold is lowered, the sugar is found in the urine (the level at which the sugar is spilled into the urine is called “Renal threshold” which is about 140 to 180 mg of sugar per 100 mol of whole blood). Presence of sugar in the urine is called “glycosuria’.
Acetone is found in the urine due to incomplete metabolism of fat usually seen in diabetic clients. Bile may be seen in the urine when there is obstructive jaundice or haemolytic disease.
Test for Albumen
Hot test
Cold test
Test for Sugar
Benedict’s Test
Reagent Strip Test – Clinistix Strip, Diastix Strip, Tes-Tape Strip
Test for Acetone
Rothera’s Test
Ketone Strip Test
Keto-Diastix Test
Test for Bile Salts
Hey’s Test
Test for Bile Pigments
Smith’s Test
Stool Specimens
Characteristics of Normal Stool
Color
Normally the color of the stool is light to dark brown due to the presence of bile pigments.
Odour
Normal stool has a pungent smell. It is normally affected by the type of bacterial flora, by the food and medications ingested.
Frequency
One to two per day and it is painless.
Consistency and Form
In adult, the stool is well formed and the consistency is semisolid.
Quantity
Quantity depends upon the type and the amount of food taken. When the roughage in the diet is increased the amount is also increased. Quantity varies from four to five ounces per day.
Composition
The feaces contain 30% water. The remaining portion consists of shed epithelium from the intestine, a considerable quantity of bacteria, a small quantity of nitrogenous matter mainly mucin, salts, calcium, phosphates, little iron and cellulose if present in the diet.
Stool of Infants
At birth the stool of infants is dark green and it is called “Meconium”. At the end of the first week, it becomes yellow and soft due to intake of milk diet.
Characteristics of Abnormal Stool
Color
Tarry black stools indicate bleeding in the upper gastrointestinal tract, the blood having been altered by the intestinal juices. The occult blood test will be positive. When the stool appears black, it is termed as “melaena”. Black stools may also result from the administration of iron or charcoal.
Clay colored stools indicate an obstruction to the flow of bile. The bile pigment that colors the stool (stercobilin) is absent. White stools may appear due to the presence of barium salts after barium tests.
Odour
In melaena and dysentery, there will be foul smell. A strong smell results from meat diet.
Frequency
Frequency is increased in diarrhea. Frequency is decreased in constipation or in clients who are on low residue diet.
Consistency and Form
In constipation, the stools are very hard. Flattened and ribbon like stools indicate some obstruction in the lumen of the bowel.
Watery stools are found in diarrhea, digestive upsets, due to bacterial invasions and after taking purgatives. “Rice water stools” are typical of cholera. “Pea soup stools” are typical of typhoid fever. Pale, bulky, semisolid and frothy stools are characteristic of sprue.
Appearance
Fresh blood in large amounts is suggestive of bleeding piles, mixing the stool with menstrual blood, bleeding from the large colon (the digestive juices will not alter this blood), malignant growths, scurvy, leukaemia or purpura.
The commonest cause of blood and mucus found in the stool is due to dysentery which may be amoebic or bacillary.
Stool may contain worms or segments of worm e.g., round worm, threadworm, hookworm and tapeworm. On microscopic examination, the stool is found to contain various amoebae, E.coli, Vibrio Cholera, A.F.B., and salmonella group of organisms.
Method of Collecting Stool Specimen
Waterproof disposable containers or wide-mouthed containers are provided with necessary instructions. The client passes stool in a clean bedpan. A small amount of stool is removed with a stick or spatula and is placed in the container. Discard the stick in the waste bin.
Sputum Specimens
Quantity
Normally no sputum is expectorated. The amount of sputum coughed up in 24 hours varies with the diseases.
Consistency
The sputum may be classified into various types according to its consistency and appearance, e.g., serous, frothy, mucoid, purulent, seropurulent and haemorrhagic.
Color
When sputum consists largely of mucus it may be colorless and translucent. Presence of pus may give rise to yellowish color. A blackish sputum contains a lot of carbon pigments as seen in excessive smoking. Presence of blood in the sputum is called as “Haemoptysis” and may appear as bright red or dark red. Bright red and frothy sputum indicates fresh bleeding from the lungs. Dark red shows that it was in the lungs for some time. Rusty color of the sputum is due to the altered haemoglobin as seen in pneumonia. Greenish color is seen in bronchiectasis. Brown color is seen in gangrenous condition of the lungs.
Appearance
If sputum is examined microscopically, a few W.B.C. and epithelial cells may be seen. Eosinophils are formed in such conditions as asthma. R.B.C. is found only when there is haemoptysis. The main organisms that are looked for in a stained sputum are tubercle bacilli (AFB). Others are streptococci, pneumococci and diphtheria bacilli.
Method of Collecting Sputum Specimen
Water proof disposable sputum cups or wide-mouthed containers are used to collect sputum specimen. A large container is required if the physician desires to have the total sputum expectorated in 24 hours. If sterile specimens are desired, a wide-mouthed sterile glass bottle with a screw cap or a sterile petri dish can be used.
The client should be given the container on the previous evening and is instructed to raise the material from the lungs by coughing and not simply expectorating the saliva or discharges from the nose or throat. The sputum should be collected in the morning before brushing the teeth and taking the food. Mouth can be rinsed with plain water and not with any antiseptic mouth washes.
To collect the sputum from a young child, use a cotton applicator and a test tube. When the sputum is coughed up, wipe off the sputum with cotton applicator and is dropped into the clean test tube. Close the test tube with a cotton plug.
Blood Specimens
Method of Collecting Blood Smear
To make a blood smear the following articles are necessary:
Clean Slides, sterile cotton swabs in a container, methylated spirit, sterile needle in a container ( a lancet), kidney tray or paper bag.
Explain the procedure to the client. Make him seated. Clean the finger tip of the client with the spirit. Ask the client to turn the face away from you. Press the finger tip and give a gentle prick with the sterile needle. Allow one drop of blood to fall on each slide. Apply a cotton swab on the finger tip over the pin prick and instruct him to apply slight pressure over it. Quickly make a smear.
Lay the slide flat on the table with the blood drop on to your right side. Grasp the slide with your left hand. Take another slide in your right hand and lower it over the blood drop quickly. Let the blood spread on the edge of the second slide. Push the slide from right to left, thus spreading the blood into a thin film evenly on the slide. Make two or three such slides. Dry the slides in the room temperature and send it to laboratory.
