Practical Guide to Diagnostic Parasitology

Garcia 3e TOC draft from mss Preface 000 Acknowledgments 000 SECTION 1 Philosophy and Approach to Diagnostic Parasitology Neglected Tropical Diseases Why Perform Diagnostic Parasitology Testing? Travel Population Movements Control Issues Global Climate Change Epidemiologic Considerations Compromised Patients; Potential Sex Bias Regarding Infection Susceptibility, Aging Approach to Therapy Who Should Perform Diagnostic Parasitology Testing? Laboratory Personnel Nonlaboratory Personnel Where Should Diagnostic Parasitology Testing Be Performed? Inpatient Setting Outpatient or Referral Setting Decentralized Testing Physician Office Laboratories Over-the-Counter (Home Care) Testing Field Sites What Factors Should Precipitate Testing? Travel and Residence History Immune Status of the Patient Clinical Symptoms Documented Previous Infection Contact with Infected Individuals Potential Outbreak Testing Occupational Testing Therapeutic Failure What Testing Should Be Performed? Routine Tests Special Testing, Reference Laboratories Specialized Referral Test Options: DPDx and Other Sites Other (Nonmicrobiological) Testing What Factors Should Be Considered When Developing Test Menus? Physical Plant Client Base Customer Requirements and Perceived Levels of Service Personnel Availability and Level of Expertise Equipment Budget Risk Management Issues Associated with Stat Testing Primary Amebic Meningoencephalitis (PAM) Granulomatous Amebic Encephalitis and Amebic Keratitis Request for Blood Films Automated Instrumentation Patient Information Conventional Microscopy SECTION 2 Parasite Classification and Relevant Body Sites Protozoa (Intestinal) Amebae, Stramenopiles Flagellates Ciliates Apicomplexa (Including Coccodia) Microsporidia (Now Classified with the Fungi) Protozoa (Other Body Sites) Amebae Flagellates Apicomplexa (Including Coccidia) Microsporidia (Now Classified with the Fungi) Protozoa (Blood and Tissue) Apicomplexa (Including Sporozoa) Flagellates Leishmaniae Trypanosomes Nematodes (Intestinal) Nematodes (Tissue) Nematodes (Blood and Tissue) Cestodes (Intestinal) Cestodes (Tissue) Trematodes (Intestinal) Trematodes (Liver and Lungs) Trematodes (Blood) Pentastomids Acanthocephala Table 2.1 Classification of human parasites Table 2.2 Cosmopolitan distribution of common parasitic infections (North America, Mexico, Central America, South America, Europe, Africa, Asia, and Oceania) Table 2.3 Body sites and possible parasites recovered (trophozoites, cysts, oocysts, spores, adults, larvae, eggs, amastigotes, and trypomastigotes) SECTION 3 Collection Options Safety Collection of Fresh Stool Specimens Collection Method Number of Specimens To Be Collected Standard Approach Different Approaches Collection Times Posttherapy Collection Specimen Type, Stability, and Need for Preservation Preservation of Stool Specimens Overview of Preservatives Formalin Sodium Acetate-Acetic Acid-Formalin (SAF) Schaudinn's Fluid Schaudinn's Fluid containing PVA (mercury base) Schaudinn's Fluid containing PVA (copper base, zinc base) Single-Vial Collection Systems (Other Than SAF) Universal Fixative (TOTAL-FIX) Quality Control for Preservatives Procedure Notes for Use of Preservatives (Stool Fixative Collection Vials) Procedure Limitations for Use of Preservatives (Stool Fixative Collection Vials) Collection of Blood Collection and Processing Stat Test Requests and Risk Management Issues Collection of Specimens from Other Body Sites Table 3.1 Fecal specimens for parasites: options for collection and processing¯a Table 3.2 Approaches to stool parasitology: test ordering Table 3.3 Preservatives and procedures commonly used in diagnostic parasitology (stool specimens) Table 3.4 Advantages of thin and thick blood films Table 3.5 Advantages and disadvantages of buffy coat films Table 3.6 Potential problems of using EDTA anticoagulant for the preparation of thin and thick blood films Table 3.7 Body sites and possible parasites recovered (trophozoites, cysts, oocysts, spores, adults, larvae, eggs, amastigotes, and trypomastigotes) SECTION 4 Specimen Test Options: Routine Diagnostic Methods and Body Sites Ova and Parasite Examination of Stool Specimens Other Diagnostic Methods for Stool Specimens Culture of Larval-Stage Nematodes Estimation of Worm Burdens through Egg Counts Hatching Test for Schistosome Eggs Screening Stool Samples for Recovery of a Tapeworm Scolex Testing of Other Intestinal Tract Specimens Examination for Pinworm Sigmoidoscopy Material Duodenal Drainage Material Duodenal Capsule Technique (Entero-Test) Urogenital Tract Specimens Sputum Aspirates Biopsy Specimens Blood Thin Blood Films Thick Blood Films Blood Staining Methods Buffy Coat Films QBC Microhematocrit Centrifugation Method Knott Concentration Membrane Filtration Technique Culture Methods Animal Inoculation and Xenodiagnosis Antibody and Antigen Detection Antibody Detection Antigen Detection, Nucleic Acid-Based Tests, and Molecular Panels Intradermal Tests Table 4.1 Body site, procedures and specimens, recommended methods and relevant parasites, and comments Table 4.2 Serologic, antigen, and probe tests used in the diagnosis of parasitic infections SECTION 5 Specific Test Procedures and Algorithms Microscopy CALIBRATION OF THE MICROSCOPE Ova and Parasite Examination DIRECT WET FECAL SMEAR Concentration (Sedimentation and Flotation) SEDIMENTATION CONCENTRATION (Formalin-Ethyl Acetate) SEDIMENTATION CONCENTRATION USING THE UNIVERSAL FIXATIVE (TOTAL-FIX) FLOTATION CONCENTRATION (Zinc Sulfate) Permanent Stained Smear PREPARATION OF MATERIAL FOR STAINING Fresh Material Preserved Material Containing PVA SAF-Preserved Material Universal Fixative (Total-Fix) Preserved Material Alternative Method for Smear Preparation Directly from Vial (Total-Fix) Stains Used in the Permanent Stained Smear TRICHROME STAIN (Wheatley's Method) IRON HEMATOXYLIN STAIN (Spencer-Monroe Method) IRON HEMATOXYLIN STAIN (Tompkins-Miller Method) MODIFIED IRON HEMATOXYLIN STAIN (Incorporating the Carbol Fuchsin Step) POLYCHROME IV STAIN CHLORAZOL BLACK E STAIN Specialized Stains for Coccidia and Microsporidia KINYOUN'S ACID-FAST STAIN (Cold Method) MODIFIED ZIEHL-NEELSEN ACID-FAST STAIN (Hot Method) CARBOL FUCHSIN NEGATIVE STAIN FOR CRYPTOSPORIDIUM (W. L. Current) RAPID SAFRANIN METHOD FOR CRYPTOSPORIDIUM (D. Baxby) RAPID SAFRANIN METHOD FOR CYCLOSPORA, USING A MICROWAVE OVEN (Govinda Visvesvara) AURAMINE O STAIN FOR COCCIDIA (Thomas Hänscheid) MODIFIED TRICHROME STAIN FOR MICROSPORIDIA (Weber, Green Counterstain) MODIFIED TRICHROME STAIN FOR MICROSPORIDIA (Ryan, Blue Counterstain) MODIFIED TRICHROME STAIN FOR MICROSPORIDIA (Evelyn Kokoskin, Hot Method) Fecal Immunoassays for Intestinal Protozoa Entamoeba histolytica Cryptosporidium spp. Giardia lamblia Kits under Development Comments on the Performance of Fecal Immunoassays Enzyme Immunoassays (Antigen Detection, No Centrifugation Recommended) Fluorescence (Visual Identification of the Organisms, Centrifugation Recommended) Lateral-Flow Cartridges (Antigen Detection, No Centrifugation Recommended) Larval Nematode Culture HARADA-MORI FILTER PAPER STRIP CULTURE BAERMANN CONCENTRATION AGAR PLATE CULTURE FOR STRONGYLOIDES STERCORALIS Other Methods for Gastrointestinal Tract Specimens EXAMINATION FOR PINWORM (Cellulose Tape Preparations) SIGMOIDOSCOPY SPECIMENS (Direct Wet Smear) SIGMOIDOSCOPY SPECIMENS (Permanent Stained Smear) DUODENAL ASPIRATES Methods for Urogenital Tract Specimens RECEIPT OF DRY SMEARS DIRECT SALINE MOUNT PERMANENT STAINED SMEAR URINE CONCENTRATION (Centrifugation) URINE CONCENTRATION (Nuclepore Membrane Filter) Preparation of Blood Films THIN BLOOD FILMS THICK BLOOD FILMS COMBINATION THICK-THIN BLOOD FILMS RISK MANAGEMENT ISSUES ASSOCIATED WITH BLOOD FILMS USE OF A REFERENCE LABORATORY FOR PARASITE BLOOD DIAGNOSTIC TESTING BLOOD FILM REPORTING WITH ADDITIONAL REPORT COMMENTS BUFFY COAT BLOOD FILMS Blood Stains STAIN OPTIONS GIEMSA STAIN Blood Concentration BUFFY COAT CONCENTRATION KNOTT CONCENTRATION MEMBRANE FILTRATION CONCENTRATION Algorithm 5.1 Procedure for processing fresh stool for the O&P examination Algorithm 5.2 Procedure for processing liquid specimens for the O&P examination Algorithm 5.3 Procedure for processing preserved stool for the O&P examination--two-vial collection kit Algorithm 5.4 Procedure for processing SAF-preserved stool for the O&P examination Algorithm 5.5 Procedure for the use of Total-Fix (Universal Fixative, single vial system) (Alternate Method for Smear Preparation Directly from Vial) Algorithm 5.6 Use of various fixatives and their recommended stains Algorithm 5.7 Ordering algorithm for laboratory examination for intestinal parasites Algorithm 5.8 Procedure for processing blood specimens for examination Table 5.1 Body site, specimen, and recommended stain(s) Table 5.2 Approaches to stool parasitology: test ordering Table 5.3 Laboratory test reports: optional comments Table 5.4 Parasitemia determined from conventional light microscopy: clinical correlation Section 6 Commonly Asked Questions about Diagnostic Parasitology Stool Parasitology Specimen Collection Intestinal Tract Fixatives Specimen Processing O&P Exam Diagnostic Methods Direct Wet Examinations Concentrations Permanent Stains Stool Immunoassay Options Molecular Test Panels (FDA Approved) APTIMA Trichomonas vaginalis Assay Affirm VPIII Microbial Identification Test Cepheid Xpert TV Assay for Trichomonas vaginalis from men and women BD MAX Enteric Parasite Panel BioFire FilmArray Gastrointestinal panel Luminex (VERIGENE II GI Flex Assay, includes Parasites) Other Pending Molecular Tests Organism Identification Protozoa Helminths Reporting Organism Identification Quantitation Proficiency Testing Wet Preparations Permanent Stained Smears Tissues or Fluids Blood Specimen Collection Specimen Processing Diagnostic Methods Organism Identification Reporting Proficiency Testing General Questions SECTION 7 Parasite Identification Protozoa Amebae (Intestinal) Entamoeba histolytica Entamoeba histolytica/Entamoeba dispar Comments on Entamoeba moshkovskii and Entamoeba bangladeshi Entamoeba bangladeshi Entamoeba hartmanni Entamoeba coli Entamoeba gingivalis Entamoeba polecki Endolimax nana Iodamoeba bütschlii Blastocystis spp. (formerly Blastocystis hominis) Flagellates (Intestinal) Giardia lamblia (G. duodenalis, G. intestinalis) Dientamoeba fragilis Chilomastix mesnili Pentatrichomonas hominis Enteromonas hominis, Retortamonas intestinalis Ciliates (Intestinal) Balantidium coli Apicomplexa (Intestinal) Cryptosporidium spp. Coccidia (Intestinal) Cyclospora cayetanensis Cystoisospora (Isospora) belli Microsporidia (Intestinal) Enterocytozoon bieneusi Encephalitozoon intestinalis, Encephalitozoon spp. Sporozoa (Blood and Tissue) Plasmodium vivax Plasmodium falciparum Plasmodium malariae Plasmodium ovale wallickeri, Plasmodium ovale curtisi Plasmodium knowlesi Malaria: Key Diagnostic Points Babesia spp. (B. microti, B. duncani, B. divergens, B. venatorum) Toxoplasma gondii Flagellates (Blood and Tissue) Leishmania spp. Trypanosoma brucei gambiense (West), T. brucei rhodesiense (East) Trypanosoma cruzi Amebae (Other Body Sites) Naegleria fowleri Acanthamoeba spp., Balamuthia mandrillaris, Sappinia diploidea Flagellates (Other Body Sites) Trichomonas vaginalis NEMATODES Intestinal Ascaris lumbricoides Trichuris trichiura;General Comments on Capillaria philippinensis Necator americanus, Ancylostoma duodenale, A. ceylanicum (Hookworms); General comments on Trichostrongylus spp. Strongyloides stercoralis Enterobius vermicularis Tissue Ancylostoma braziliense, Ancylostoma caninum, Uncinaria stenocephala (Dog and Cat Hookworms) Toxocara canis, Toxocara cati (Dog and Cat Ascarid Worms) Dracunculus medinensis Trichinella spiralis Blood and Tissue Filarial Worms CESTODES Intestinal Taenia saginata Taenia solium Diphyllobothrium latum Hymenolepis (Rodentolepis) nana Hymenolepis diminuta Dipylidium caninum Tissue Echinococcus granulosus, E. multilocularis, E. vogeli, E. oligarthrus TREMATODES Intestinal Fasciolopsis buski Liver and Lungs Paragonimus westermani, Paragonimus mexicanus, Paragonimus kellicotti Fasciola hepatica Clonorchis sinensis (Chinese liver fluke) (Opisthorchis sinensis) Blood Schistosoma spp. (S. mansoni, S. haematobium, S. japonicum, S. mekongi, S. malayensis, S. intercalatum) SECTION 8 Common Problems in Parasite Identification Table 8.1 Entamoeba spp., trophozoites versus macrophages Table 8.2 Entamoeba spp., cysts versus polymorphonuclear leukocytes Table 8.3 Entamoeba histolytica versus Entamoeba coli precysts and cysts Table 8.4 Endolimax nana versus Dientamoeba fragilis SECTION 9 Identification Aids Diagnostic Considerations Table 9.1 Rapid diagnostic procedures Table 9.2 Diagnostic characteristics for organisms in wet mounts (direct or concentration sediment) Table 9.3 Diagnostic characteristics for organisms in permanent stained smears Key 9.1 Identification of intestinal amebae (permanent stained smear) Key 9.2 Identification of intestinal flagellates Key 9.3 Identification of helminth eggs Key 9.4 Identification of microfilariae Protozoa Table 9.4 Intestinal protozoa: trophozoites of common amebae Table 9.5 Intestinal protozoa: cysts of common amebae Table 9.6 Intestinal protozoa: trophozoites of less common amebae Table 9.7 Intestinal protozoa: cysts of less common amebae Table 9.8 Morphologic criteria used to identifyBlastocystisspp. Table 9.9 Intestinal protozoa: trophozoites of flagellates Table 9.10 Intestinal protozoa: cysts of flagellates Table 9.11 Intestinal protozoa: ciliates Table 9.12 Apicomplexa Table 9.13 Microsporidia (related to the fungi), general information Table 9.14 Microsporidia: recommended diagnostic techniques Table 9.15 Comparison of Naegleria fowleri, Acanthamoeba spp., Balamuthia mandrillaris, and Sappinia diploidea Table 9.16 Characteristics of Trichomonas vaginalis Table 9.17 Key characteristics of intestinal tract/urogenital system protozoa Helminths Table 9.18 Normal life spans of the most common intestinal nematodes Table 9.19 Characteristics of the most common intestinal nematodes Table 9.20 Tissue nematodes Table 9.21 Trichinella spiralis: life cycle stages and clinical conditions Table 9.22 Characteristics of human microfilariae Table 9.23 Characteristics of cestode parasites (intestinal) Table 9.24 Tissue cestodes Table 9.25 Characteristics of intestinal trematodes Table 9.26 Characteristics of liver and lung trematodes Table 9.27 Human paragonimiasis Table 9.28 Characteristics of blood trematodes Table 9.29 Key characteristics of helminths Blood Parasites Table 9.30 Malaria characteristics with fresh blood or blood collected using EDTA with no extended lag time Table 9.31 Potential problems using EDTA anticoagulant for the preparation of thin and thick blood films Table 9.32 Plasmodia in Giemsa-stained thin blood smears Table 9.33 Relevant issues for handling requests for blood parasite infections Table 9.34 Features of human leishmanial infectionsa Table 9.35 Characteristics of American trypanosomiasis Table 9.36 Characteristics of East and West African trypanosomiasis Table 9.37 Key characteristics of blood parasites Index