A gram stain is a lab test used to detect bacteria or fungi in a sample taken from the site of a suspected infection. Prior to culturing a sputum specimen, a gram stain should be performed to evaluate the quality of the specimen. Please note that the quality of the smear too heavy or too light cell concentration will affect the gram stain results. Pdf correlation of sputum grams stain and culture in lower. Up to 30% of bacterial meningitis cases may not be detected.
Closedopen abscess, lower respiratory, fluid, tissue, or swab supplies. Transport, and storage in pr murray et al, ed, manual of clinical. Basic classification of medically important bacteria. Principle, procedure, interpretation, examples and animation last updated.
Aug, 2017 sputum is a type of thick mucus that is produced by the lungs when they are diseased or damaged. Mycobacteria, which do not stain well by gram stain. The cellwall of mycobacteria contain high concentration of lipid making them waxy, hydrophobic, and impermeable to routine stain such as the gram stain. June 12, 2018 by sagar aryal gram staining is the common, important, and most used differential staining techniques in microbiology, which was introduced by danish bacteriologist hans christian gram in. A gram stain is a laboratory procedure used to detect the presence of. A sputum gram stain is a laboratory test used to detect bacteria in a sputum sample. Our gramstain reagents are intended to be used as a differential stain for. Pus, body fluid, sputum, or swab of cells taken from the site of an infection.
The gram stain is a differential method of staining used to assign bacteria to one of two groups grampositive and gramnegative based on the properties of their cell walls. Grams stain is one of the most frequently used processes in identifying bacteria and is used daily in hospitals. Vegetative cells seen on gram stain of blood and impression smears are in short chains of 24 cells that are encapsulated, which may be seen on the gram stain as clear. Sputum coughed or induced endotracheal tube aspirate. Jun 15, 2014 t o the e ditor the sputum gram stain and culture are crucial components of the diagnostic workup in patients with communityacquired pneumonia cap. Prior studies have demonstrated a reduced yield of sputum studies when antibiotics are initiated prior to obtaining a sputum specimen 14, but we are aware of only a single study that relates this yield of sputum studies to the time after. Corynebacterium diptheria seen in gram staining 35.
They may order it if you have symptoms of a respiratory infection. All gram stains are scanned for the presence or absence of white blood cells indicative of infection and squamous epithelial cells indicative of mucosal contamination that give information about the specimen quality. The usefulness of sputum gram stain in patients with cap is controversial. Learn vocabulary, terms, and more with flashcards, games, and other study tools. Identifying microorganisms in normally sterile body fluids screening sputum specimens for acceptability for bacterial culture guiding initial antimicrobial therapy. Standard operating procedure references applicable to detail. Sputum examination an overview sciencedirect topics. Gram stains alone are rarely appropriate without a culture request. Work up of wound cultures in the microbiology laboratory. A gram stain of the cultured organism is also shown. Similarly, grams stain usually predicted the positive cultures and large bacterial load, although it has been shown to be less reliable at detecting the presence of bacteria than sputum culture itself. Gram or giemsa stain for bacteria, fungi or cell types the following testing may be added if appropriate based on findings for. The procedure is named for the person who developed the technique, danish bacteriologist hans christian gram. However, for some authors, when performed, this technique is able to identify.
One of two criteria are currently used to determine if the specimen is contaminated with oral flora organisms, which would make the specimen unsuitable for culture. Tilt the slide slightly and gently rinse with tap water or distilled water using a wash bottle. The investigators used various criteria to predict the presence of pneumococci in the culture of the sputum specimen. Started in 1995, this collection now contains 6760 interlinked topic pages divided into a tree of 31 specialty books and 732 chapters. Accuracy of grams stain the previous slides show a summary of an attempt to assess the accuracy of grams stain for identifying pneumococci in sputum. The usefulness of the sputum gram s stain is controversial. Examination of sputum specimen in laboratory microbiology. The sputum specimen can be examined by gram stain method, acid fast staining method and also the sputum culture is often done on blood agar plate and tubes of thioglycollate medium to isolate the microbe that might be associated with the ailment. Prepared microscope slide collection containertube.
The use of standard laboratory reference texts is encouraged and should be observed 4,5. Gram stain is one of the most common staining technique used for examining specimens suspected to contain bacteriologic agents. Jun 12, 2018 acidfast stain principle, procedure, interpretation and examples. Gram stain sputum test test results, normal range, cost and. Sterile container or culture transport swab dacron or rayon swab with aluminum or plastic shaft with either stuart or amies liquid medium specimen volume. Christian gram in 1884, and categorizes bacteria according to their gram character gram positive or gram negative. Sputum is the material that appears from a patients air passage when coughed deeply. They demonstrate the importance of careful analysis of bacterial morphology. Sputum gram stain assessment in relation to sputum. The gram stain is a complex and differential staining procedure that remains a useful.
When acceptable sputum is obtained, the specificity of the gram stain for pneumococcal pneumonia is estimated to be greater than 80%. The evaluator must understand appropriate methods and ensure they are being followed. The clinical microbiology laboratory in the diagnosis of. This differential staining procedure separates most bacteria into two groups on the basis of cell wall composition. Interpretation of gram stains for the nonmicrobiologist. This fastidious organism requires chocolate agar for growth. The gram stain involves staining bacteria, fixing the color with a mordant, decolorizing the cells, and applying a counterstain. This metaanalysis was designed to evaluate the sensitivity and specificity of the sputum gram s stain in communityacquired pneumococcal pneumonia. Sputum is the material that comes up from your air passages when you cough very deeply. Laboratory perspective of gram staining and its significance in.
Quantitative gram stain interpretation criteria used by. Relationship of sputum color to nature and outpatient. The diagnostic performance of sputum gram stain in cap varies in different studies. Overheating of smears when heat fixation is used d. The filtergram stain was approximately 100fold more sensitive than the slidegram stain. It is a substance known as phlegm, and it can be an indicator of many respiratory infections. In general for initial evaluation, send csf for cell count, glucose also draw simultaneous blood glucose, and protein with gram stain and bacterial culture do not routinely order bacterial antigens, afb, and fungi, or pcr for herpes until initial results from routine studies are available. A sputum gram satin is a laboratory test used to detect bacteria in a sputum sample. Definition, colors, causes, and when to see a doctor. Sputum grams stain in communityacquired pneumococcal. Grampositive bacteria thick layer of peptidoglycan90% of cell wall stains purple. Presumptive identification based on gram stain and morphologic features. Because of the high mortality rate, the rapid identification of patients requiring. While some authors have insisted on the usefulness of sputum gram stain 1719, others have argued for a limited value of this method.
The best sputum samples contain very little saliva, as saliva contaminates the sample with oral bacteria. It is the differential staining techniques which was first developed by ziehl and later on modified by neelsen. Oct 18, 2014 the usefulness of sputum gram stain in patients with cap is controversial. A sputum grams stain is a laboratory test that allows your doctor to diagnose a bacterial infection in your respiratory tract. Apr 04, 2016 corynebacterium diptheria seen in gram staining 35. Place slide with heat fixed smear on staining tray. The previous slides show a summary of an attempt to assess the accuracy of gram s stain for identifying pneumococci in sputum. Work up of wound cultures in the microbiology laboratory watch your ps and qs susan sharp, ph. The gram stain method is one of the most commonly used methods to rapidly identify. The simplest and preliminary method of lung cancer diagnosis a retrospective analysis of 8690 samples of symptomatic patients v. They are also resistant to acid and alcohol and is described as acid fast bacilli afb or acid alcohol fast bacilli aafb. Oct 05, 2018 gram stain is one of the most common staining technique used for examining specimens suspected to contain bacteriologic agents. Culture for aerobic flora and gram stain to assess specimen quality. Use of the gram stain for diagnosis of infectious disease part two.
Sputum gram stain may be a useful procedure to screen for pulmonary strongyloidiasis in steroidtreated patients with chronic lung disease who come from an endemic area. Prior studies have demonstrated a reduced yield of sputum studies when antibiotics are initiated prior to obtaining a sputum specimen 14, but we are aware of only a single study that relates this yield of sputum studies to the. The clinical microbiology laboratory in the diagnosis of lower. Misinformation from sputum cultures without microscopic. Validation of sputum gram stain for treatment of community. There was a thrombosis of the left internal carotid artery with infarction of the left cerebral hemisphere. The gram staining procedure is based on the fact that crystal violet stains the. Acidfast stain principle, procedure, interpretation and examples. Pdf on jan 1, 20, anuradha mokkapati and others published correlation of sputum grams stain and culture in lower respiratory tract. Gram variable observations in gram staining the gram staining procedure does not always give clearcut results. The direct microscopic examination of specimens and cultures can provide a rapid presumptive diagnosis meanwhile gram staining is a differential stain that provide morphological information regarding the shape of cell,the type of cell arrangement that is single.
Kaiser permanente, portland oregon workup of wound culturestwo approaches. Grampositive bacteria have a thick meshlike cell wall made of. Yield of sputum culture in bacteremic pneumococcal. The sputum gram stain, a standard procedure in clinical microbiology, is used for assessment of specimen quality, for preliminary, rapid diagnostic information. The sputum gram stain, a standard procedure in clinical microbiology, is used for assessment of specimen quality, for preliminary, rapid diagnostic information, and for laboratory quality assurance. Sputum specimens showing 10 squamous epithelial cells per. At low power, large fungal forms all fungi are gram positive can often be seen and the staining.
The preparation and analysis of a gram stain is a highly complex procedure that requires extensive experience in order for a correct result to be reported. Specimen adequacy is assessed by the laboratory technologists by examining a gram stain or cytology stain of the sputum. Also referred to as phlegm, sputum is produced in the bronchi and bronchioles of the respiratory system and coughed up from the lower airways and should not be confused or mistaken for saliva, which is secreted in the mouth for digestion purposes. Jan 08, 2020 the gram staining technique is the most important and widely used microbiological differential staining technique. This 2nd edition of standard manual for laboratory technicians on sputum smear. The most common detected bacteria in sputum of patients. Gently flood smear with crystal violet and let stand for 1 minute. In addition this stain also allows determination of cell morphology, size, and arrangement. Sputum microscopy culture, staining, requirements and. Following decolorization, sputum smear is counterstained with malachite green, or methylene blue which stains the background material, providing a contrast colour against which the red afb can be seen. Sputum microscopy culture, staining, requirements and observations. Sputum gram stain uf health, university of florida health.
Principle, procedure and results february 2, 2015 acharya tankeshwar bacteriology, staining techniques in microbiology 45 this post was most recently updated on august 26th, 2019. Gently flood the smear with grams iodine and let stand for 1 minute. Qscore system o q score system scores the gram stain of the specimen giving a positive value to the. The microscopic examination of gram stained sputum specimens. Semiquantitation of bacteria in sputum gram stains journal of. Yield of sputum culture in bacteremic pneumococcal pneumonia. There was a massive embolus of the right pulmonary artery. A positive gram stain result means the bacteria has a thick peptidoglycan layer in the cell wall that retains the stain after it is washed away from the rest of the sample. The mechanism of gram stain is based on the distinctive chemistry and physical properties of the cell wall. These specimens are difficult to obtain and should not be rejected unless the entire sample. The gram stain test is one of the most commonly used methods to identify the cause of a bacterial infection including pneumonia. The filtergram stain detected 2 to 100 bacteria, whereas the slidegram stain failed to detect less than. The gram stain is an empirical method of differentiating bacterial species into two.
The gram stain has a broad staining spectrum 2,3 and classifies bacteria as either gram positive or gram negative. Doctors give unbiased, helpful information on indications, contraindications, benefits, and complications. Microbiology fact sheet sputum mc interpretation of results. Sputum is a type of thick mucus that is produced by the lungs when they are diseased or damaged. Pneumonia, contd 32 gram stain of the sputum from a patient with staphylococcus aureus pneumonia demonstrating clusters of gram positive cocci some of which are associated with the pmns oil immersion, x 33. A sputum gram s stain is a laboratory test that allows your doctor to diagnose a bacterial infection in your respiratory tract. Gram stain is not reliable for diagnosis of cervical, rectal, pharyngeal or asymptomatic urethral gonococcal infection. The case reports of these patients and photomicrographs of the larval forms by gram stain are presented.
T o the e ditor the sputum gram stain and culture are crucial components of the diagnostic workup in patients with communityacquired pneumonia cap. It is a primary test which quickly and cost effectively divides bacteria into one of two types. Sputum, grams stain, bartletts criteria, sputum culture. Correlate gram stain and culture to determine significant isolates. Minibronchoalveolar bal culture procedure, quantitative. Gramnegative bacteria thin layer of peptidoglycan10% of cell wall and high lipid content stains redpink. The gram stain method is one of the most commonly used methods to rapidly identify the cause of a bacterial infection, including pneumonia. Several systems are used to assess specimen quality using the sputum gram stain. There are two procedures commonly used for acidfast staining.
Flood airdried, heatfixed smear of cells for 1 minute with crystal violet staining reagent. Results obtained by culture without evaluation for contamination may be noncontributory or misleading. In recent reports, the impact of gram staining results on patient mortality has been. This is especially true for samples for lab testing in cytology or microbiology. Honestly, the amount of people who dont know what a. Essentially, sputum is composed of a mixture of saliva and mucus. Interpretation of sputum gram stains for communityacquired pneumonia.
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