What are the other Names for this Test?
- Test for Molecular Diagnosis of Oesophagostomiasis
What is Molecular Testing for Oesophagostomiasis?
- Molecular Testing for Oesophagostomiasis is based on identifying specific stretches of DNA sequences unique to Oesophagostomum spp.
- The lab test results may be useful in identifying the specific organism causing the infection, to ensure uninfected status, to differentiate between different disease-causing microbes, and to confirm a preliminary diagnosis
- The test results may also be useful in conducting further lab tests to identify the sensitivity of Oesophagostomum sppto anti-parasitic agents, so that effective treatment can be undertaken
- Oesophagostomiasis is a parasitic worm infection brought on by several species of nematodes (roundworms) belonging to the genus Oesophagostomum, of which Oesophagostomum bifurcum (or O. bifurcum) affects humans the most
- Humans and other mammals are known to act as definitive hosts for the parasite, allowing the infection to last for years at a time. This parasite is found in warmer climates, such as the tropics, or other regions that are favorable for hatching of parasite eggs. Most clinical cases are reported from Ghana and Togo (two countries in Africa)
- O. bifurcum is primarily a monkey parasite, and therefore, areas with monkey populations often report a higher frequency of oesophagostomiasis. Additionally, livestock, such as pigs, sheep, and goats, can also carry the infection
- Poor hygienic standards and warm climates pose an increased risk for contracting the disease, which is transmitted via contaminated soil/feces
- Some common symptoms of this infection are pain in the lower right abdomen, presence of nodules, or distention of abdominal organs. Complications from the disease may severely affect the gastrointestinal tract and result in bowel obstruction and perforation
Molecular testing for infectious organisms (viruses, bacteria, fungi, and parasites) can be performed using a variety of methods. Some of these methods include:
- In situ hybridization techniques, such as fluorescence in situ hybridization (FISH)
- Immunohistochemistry (IHC)
- 16S rRNA for bacterial pathogens
- Branch DNA (bDNA) assays
- Hybrid capture assay
- Nucleic acid amplification tests (NAATs), such as species-specific polymerase chain reaction (PCR), real-rime PCR
- Analysis of Ribosomal DNA (rDNA)
- Transcription mediated amplification
- Next-generation sequencing (NGS)
- Reverse hybridization
- Comparative genomic hybridization (CGH)
- Whole genome sequencing
- Flow cytometric assays with specific microbeads to detect pathogens
- mRNA analysis
- Nucleic acid arrays
- Mass spectrometric analysis
Note: There may be limitations to the testing due to the method being used. Consultation with your healthcare provider will help in determining the right test and right molecular method, based on individual circumstances.
What are the Clinical Indications for performing the Molecular Testing for Oesophagostomiasis Test?
Molecular Testing for Oesophagostomiasis is undertaken in the following situations:
- To assist in or confirm, the initial diagnosis of oesophagostomiasis
- To distinguish between parasites that produce similar symptoms
- To eliminate suspected parasites
- To help in determining treatment options
How is the Specimen Collected for Molecular Testing for Oesophagostomiasis?
Following is the specimen collection process for Molecular Testing for Oesophagostomiasis:
The specimen sample requirements may vary from lab to lab. Hence, it is important to contact the testing lab for exact specimen requirements, before initiating the testing process.
Sample on which the test is performed may include:
- Peripheral blood in individuals showing signs and symptoms suspected of oesophagostomiasis
- Blood or tissue sample from individuals who are blood or organ donors
- Body fluids such as saliva, urine, cerebrospinal fluid (CSF), pleural fluid, ascites fluid, drainage from abscesses and lesions, sputum, phlegm, and mucus (from nose, throat and genitals)
- Specimen obtained through swaps from different sites in the body, such as nasal, throat, corneal, vaginal, rectal and from lesions
- Fresh tissue from biopsy (of abdominal nodule)
- Fresh tissue from autopsy sample
- Fresh tissue from fetal demise
- Products of conception sample from aborted pregnancy
Turnaround time for test results
- Depending on the location of testing, it may take anywhere from 3 days to 3 weeks from the time of sample collection, to obtain test results
Sample storage information
- Many hospitals preserve the paraffin blocks for at least 7 years. In general, older paraffin blocks (over 5 years) may affect the detection of specific mutations, due to degradation of the tissue specimen over time
Cost ofMolecular Testing forOesophagostomiasis:
- The cost of the test procedure depends on a variety of factors, such as the type of your health insurance, annual deductibles, co-pay requirements, whether your healthcare provider/facility is in-network or out-of-network of your insurance company
- In many cases, an estimate may be provided before the test is conducted. The final amount may depend upon the findings during the test procedure and post-operative care, if required
What is the Significance of the Molecular Testing for Oesophagostomiasis Result?
The significance of Molecular Testing for Oesophagostomiasis is explained below:
- A positive test result helps aid, and in some cases, confirm the presence of a specific pathogen
- The test results can help in the following manner:
- Ensure that an individual does not have an infection - as part of a routine screening procedure
- Ensure that prospective donors do not have an infection that can be passed on to the recipients
- Identify the pathogen in an individual suffering from an active infection
- Exclude other conditions presenting with similar signs and symptoms
- Make treatment decisions
- Determine the prognosis of an affected individual
The laboratory test results are NOT to be interpreted as results of a "stand-alone" test. The test results have to be interpreted after correlating with suitable clinical findings and additional supplemental tests/information. Your healthcare providers will explain the meaning of your tests results, based on the overall clinical scenario.
Additional and Relevant Useful Information:
- Many laboratories may not have the capability to perform molecular diagnostic tests. Only highly-specialized labs with advanced facilities and testing procedures may offer these tests
- Oesophagostomiasis is also known as, or is closely-related to the medical condition Dapaong Tumor
Certain medications may influence the outcome of the test. Hence, it is important to inform your healthcare provider of the complete list of medications (including any herbal supplements) you are currently taking. This will help the healthcare provider interpret your test results more accurately and avoid any possibility of a misdiagnosis.
What are some Useful Resources for Additional Information?
Please visit our Laboratory Procedures Center for more physician-approved health information:
References and Information Sources used for the Article:
https://www.cdc.gov/anthrax/specificgroups/lab-professionals/recommended-specimen.html (accessed on 06/02/2017)
http://www.merckmanuals.com/home/infections/diagnosis-of-infectious-disease/diagnosis-of-infectious-disease (accessed on 06/02/2017)
https://www.fda.gov/biologicsbloodvaccines/bloodbloodproducts/approvedproducts/licensedproductsblas/blooddonorscreening/infectiousdisease/default.htm (accessed on 06/02/2017)
https://web.stanford.edu/group/parasites/ParaSites2009/AndrewPlan_Oesophagostomum/AndrewPlan_Oesophagostomum.htm (accessed on 06/02/2017)
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