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Informational Tables

- 1.1 Parasite Classification | - 1.2 Body Site, Specimens, Procedures, Parasites, Comments | - 1.3 STAT Testing in Parasitology | - 1.4 Test Issues and Reports: Computer Report Comments| - 1.5 Rapid Diagnostic Testing
- 2.1 Stool Testing Order Recommendations | - 2.2 Fecal specimens for parasites: options for collection and processinga2 | - 2.3 Preservatives used for Stool Specimens
- 3.1 Body Sites and Specimen Collection | - 3.2 Body sites and the most common parasites recovered | - 3.3 Body Site, Specimens and Recommended Stain | - 3.4 Examination of tissues and body fluids | - 3.5 Parasitic Infections: Clinical Findings Healthy/Compromised Hosts | - 3.6 Microscope Calibration | - 3.7 Serologic, Antigen, and Probe Tests for Parasite Diagnosis
- 4.1 Protozoa: Intestinal Tract, Urogenital System: Key Characteristics | - 4.2 Tissue Protozoa: Characteristics | - 4.3 Tips on Performance of Fecal Immunoassays for Intestinal Protozoa
5.1 Helminths: Key Characteristics | 5.2 Helminth Parasites Associated with Eosinophilia
6.1 Reference Laboratory for Parasite Blood Testing | 6.2 Parasites Found in Blood: Characteristics
7.1 Malaria (5 Species) (2 P. ovale subspecies) | 7.2 Malaria (5 Species, Images) | 7.3 Rapid Malaria Testing (BinaxNOW Malaria Test) | 7.4 Malaria Parasitemia Method | 7.5 Malaria Parasitemia Interpretation
- USE OF A REFERENCE LABORATORY FOR PARASITE BLOOD DIAGNOSTIC TESTING (Including the Binax Rapid Test and Report Comments)

- HELMINTH PARASITES ASSOCIATED WITH EOSINOPHILIA | - Histology: Staining Characteristics - Table 1 | - Histological Identification of Parasites - Table 2 | - Microscope Calibration | - Figures for Histology Identification Table 2
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Table 2.1 Approaches to Stool Parasitology: Test Ordering Recommendations

Patient and/or situation

Test ordereda

Follow-up test ordered

Patient with diarrhea and AIDS or other cause of immune deficiency
or
Patient with diarrhea involved in a potential waterborne outbreak (municipal water supply)

Cryptosporidium or Giardia/Cryptosporidium immunoassay

If immunoassays are negative and symptoms continue, special stains for microsporidia (modified trichrome stain) and other coccidia (modified acid-fast stain) and O&P exam should be performed.

Patient with diarrhea (nursery school, day care center, camper, backpacker)
or
Patient with diarrhea involved in a potential waterborne outbreak (resort setting)
or
Patient from areas within the United States where Giardia is the most common parasite found

Giardia
or Giardia/Cryptosporidium immunoassay

If immunoassays are negative and symptoms continue, special stains for microsporidia and other coccidia (see above) and O&P exam should be performed

Patient with diarrhea and relevant travel history outside of the United States
or
Patient with diarrhea who is a past or present resident of a developing country
or
Patient in an area of the United States where parasites other than Giardia are found (large metropolitan centers such as New York, Los Angeles, Washington, DC, Miami)

O&P exam, Entamoeba histolytica/ E. dispar immunoassay; immunoassay for confirmation of E. histolytica; various tests for Strongyloides may be relevant (even in the absence of eosinophilia), particularly if there is any history of pneumonia (migrating larvae in lungs), sepsis, or meningitis (fecal bacteria carried by migrating larvae); the agar culture plate is the most sensitive diagnostic approach for Strongyloides.

The O&P exam is designed to detect and identify a broad range of parasites (amebae, flagellates, ciliates, Cystoisospora belli, and helminths). If exams are negative and symptoms continue, special tests for coccidia (fecal immunoassays, modified acid-fast stains, autofluorescence) and microsporidia (modified trichrome stains, calcofluor white stains) should be performed; fluorescent stains are also options.

Patient with unexplained eosinophilia

Although the O&P exam is recommended, the agar plate culture for Strongyloides stercoralis (it is more sensitive than the O&P exam) is also recommended, particularly if there is any history of pneumonia (migrating larvae in lungs), sepsis or meningitis (fecal bacteria carried by migrating larvae).

If tests are negative and symptoms continue, additional O&P exams and special tests for microsporidia (modified trichrome stains, calcofluor white stains, fluorescent stains) and other coccidia (modified acid-fast stains, autofluorescence, fluorescent stains) should be performed.

Patient with diarrhea (suspected food-borne outbreak)

Test for Cyclospora cayetanensis (modified acid-fast stain, autofluorescence, fluorescent stains).

If tests are negative and symptoms continue, special procedures for microsporidia and other coccidia and O&P exam should be performed.

a Depending on the particular immunoassay kit used, various single or multiple organisms may be included. Selection of a particular kit depends on many variables: clinical relevance, cost, ease of performance, training, personnel availability, number of test orders, training of physician clients, sensitivity, specificity, equipment, time to result, etc. Very few laboratories handle this type of testing exactly the same. Many options are clinically relevant and acceptable for good patient care. It is critical that the laboratory report indicate specifically which organisms could be identified by the kit; a negative report should list the organisms relevant to that particular kit.It is important to remember that sensitivity and specificity data for all of these fecal immunoassay kits (FA, enzyme immunoassay, cartridge formats) are comparable.