ERRORS IN THROAT SWAB COLLECTION , CULTURING AND REPORTING IN PEDIATRIC PATIENTS
Dr.T.V.Rao MD We do receive many specimens in Microbiology departments from young children, and infants, The errors start from collecting the throat, many times the throat is not reached and swabs are collected in erratic ways and laboratories too report the errors, the reasons being very few staff are trained in the meticulous ways in collecting the pediatric specimens, However in developed countries have many trained child caring nurses however we certainly have to work in a compromised conditions in technical and clinical competency in collecting specimens , Coming to analysis much of the reports express either a sterile culture report and many irrelevant microbes are reported from many uncontrolled laboratories, today we see few of the results reporting Moraxella, Pneumococcus, Diphtheroids may be mistaken to be Diphtheria bacillus, however we should do a special stain at least a Albert's stain and culturing the swabs on selective media for Diphtheria, the minimal expectations in throat swab culture from a pediatrician in routine practice is Group A Streptococcal infection as when present with raised ASO levels, and ill-defined arthritis suspected to be Rheumatic fever, However in many developing countries look out about Diphtheria Infection involving throat presenting with pseudo membrane, or fever with toxicity and tachycardia For example, the presence of group A streptococcus bacteria (Streptococcus pyogenes) in throat is a key sign that child may have strep throat. Many cases of sore throat are caused by Virus but mistaken to be bacterial,
TECHNIQUE Of Collecting A THROAT SWAB
The child undergoing the specimen collection for throat culture is asked to tilt his or her head back and open his or her mouth. However, in infants the mother or care taker to be instructed, The health professional will press the tongue down with a tongue depressor and examine the mouth and throat. A clean swab will be rubbed over the back of the throat, around the tonsils, and over any red areas or sores to collect a sample.
Using a sterile cotton swab, touch the infected area with the swab with several strokes to collect any pathogenic or bacteria for a microbiologist to analyze.
Be careful not to touch the tongue, uvula, or lips due to possible contamination.
This should not be a painful procedure but expect your patient to gag since you will touch the back of her throat. At least few people working in the department to be trained
Prepare the swab for transportation to the laboratory for analysis. Always label the sample with patient name, date of birth, and patient ID and not forgetting the clinical details, and possible Antibiotic administration,
ALTERNATIVE APPROACHES -The sample may also be collected using a throat washout. For this test, the patient will gargle a small amount of salt water and then spit the fluid into a clean cup. This method gives a larger sample than a throat swab and may make the culture more reliable. However, it is not possible in infants and non-cooperative groups
CULTURING METHODS and RESULTS - The most portion of a specimen was identified, inoculated onto agar plates by swab and streaked for isolation of colonies. Media inoculated were 5% sheep blood agar, chocolate agar, MacConkey agar, mannitol-salt agar, all from plates were incubated at 35 degrees centigrade for a minimum of 72 hours, and observed for growth of pathogens specified by the SOP available in the laboratory , including Staphylococcus aureus, beta-hemolytic streptococci, Streptococcus pneumonia, Streptococcus milleri group, Haemophilus influenza, Moraxella catarrhalis, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Achromobacter species, Acinetobacter species, Burkholderia species and yeast
It is essential to pick only CLINICALLY essential to be picked for identification and reported as Group A streptococcus. This bacterium can cause strep throat, scarlet fever, and rheumatic fever. A throat culture is more accurate than the rapid strep test. The rapid strep test can give false-negative results even when strep bacteria are present. When the results of a rapid strep test are negative, many doctors recommend doing a throat culture to make sure that strep throat is not present.
Candida albicans. This fungus causes thrush an infection of the mouth and tongue and sometimes of the throat. Bottle fed infants will have much colonization of Candida, the matters left to the pediatrician’s discrimination to treat or not to treat
Neisseria meningitis. This bacterium can cause meningitis. Can be present as colonizer of the throat in times of Epidemics with N meningitides
Obtaining a “standard” culture may lead to identification of a organism, but may be subject to differences in competitive growth patterns in vitro versus in vivo.
NOTE - THROAT SWAB IS MOST ERROR PRONE AT COLLECTION AND REPORTING THE CLINICALLY RELEVANT RESULTS
I wish the new generation of Microbiologists to read 13th edition of Macy Diagnostic Microbiology for optimal reporting on Syndrome based approaches
Formulated by Dr.T.V.Rao MD for Online resources on Improving health care in Developing countries ‘
Dr.T.V.Rao MD We do receive many specimens in Microbiology departments from young children, and infants, The errors start from collecting the throat, many times the throat is not reached and swabs are collected in erratic ways and laboratories too report the errors, the reasons being very few staff are trained in the meticulous ways in collecting the pediatric specimens, However in developed countries have many trained child caring nurses however we certainly have to work in a compromised conditions in technical and clinical competency in collecting specimens , Coming to analysis much of the reports express either a sterile culture report and many irrelevant microbes are reported from many uncontrolled laboratories, today we see few of the results reporting Moraxella, Pneumococcus, Diphtheroids may be mistaken to be Diphtheria bacillus, however we should do a special stain at least a Albert's stain and culturing the swabs on selective media for Diphtheria, the minimal expectations in throat swab culture from a pediatrician in routine practice is Group A Streptococcal infection as when present with raised ASO levels, and ill-defined arthritis suspected to be Rheumatic fever, However in many developing countries look out about Diphtheria Infection involving throat presenting with pseudo membrane, or fever with toxicity and tachycardia For example, the presence of group A streptococcus bacteria (Streptococcus pyogenes) in throat is a key sign that child may have strep throat. Many cases of sore throat are caused by Virus but mistaken to be bacterial,
TECHNIQUE Of Collecting A THROAT SWAB
The child undergoing the specimen collection for throat culture is asked to tilt his or her head back and open his or her mouth. However, in infants the mother or care taker to be instructed, The health professional will press the tongue down with a tongue depressor and examine the mouth and throat. A clean swab will be rubbed over the back of the throat, around the tonsils, and over any red areas or sores to collect a sample.
Using a sterile cotton swab, touch the infected area with the swab with several strokes to collect any pathogenic or bacteria for a microbiologist to analyze.
Be careful not to touch the tongue, uvula, or lips due to possible contamination.
This should not be a painful procedure but expect your patient to gag since you will touch the back of her throat. At least few people working in the department to be trained
Prepare the swab for transportation to the laboratory for analysis. Always label the sample with patient name, date of birth, and patient ID and not forgetting the clinical details, and possible Antibiotic administration,
ALTERNATIVE APPROACHES -The sample may also be collected using a throat washout. For this test, the patient will gargle a small amount of salt water and then spit the fluid into a clean cup. This method gives a larger sample than a throat swab and may make the culture more reliable. However, it is not possible in infants and non-cooperative groups
CULTURING METHODS and RESULTS - The most portion of a specimen was identified, inoculated onto agar plates by swab and streaked for isolation of colonies. Media inoculated were 5% sheep blood agar, chocolate agar, MacConkey agar, mannitol-salt agar, all from plates were incubated at 35 degrees centigrade for a minimum of 72 hours, and observed for growth of pathogens specified by the SOP available in the laboratory , including Staphylococcus aureus, beta-hemolytic streptococci, Streptococcus pneumonia, Streptococcus milleri group, Haemophilus influenza, Moraxella catarrhalis, Pseudomonas aeruginosa, Stenotrophomonas maltophilia, Achromobacter species, Acinetobacter species, Burkholderia species and yeast
It is essential to pick only CLINICALLY essential to be picked for identification and reported as Group A streptococcus. This bacterium can cause strep throat, scarlet fever, and rheumatic fever. A throat culture is more accurate than the rapid strep test. The rapid strep test can give false-negative results even when strep bacteria are present. When the results of a rapid strep test are negative, many doctors recommend doing a throat culture to make sure that strep throat is not present.
Candida albicans. This fungus causes thrush an infection of the mouth and tongue and sometimes of the throat. Bottle fed infants will have much colonization of Candida, the matters left to the pediatrician’s discrimination to treat or not to treat
Neisseria meningitis. This bacterium can cause meningitis. Can be present as colonizer of the throat in times of Epidemics with N meningitides
Obtaining a “standard” culture may lead to identification of a organism, but may be subject to differences in competitive growth patterns in vitro versus in vivo.
NOTE - THROAT SWAB IS MOST ERROR PRONE AT COLLECTION AND REPORTING THE CLINICALLY RELEVANT RESULTS
I wish the new generation of Microbiologists to read 13th edition of Macy Diagnostic Microbiology for optimal reporting on Syndrome based approaches
Formulated by Dr.T.V.Rao MD for Online resources on Improving health care in Developing countries ‘
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