Parasitology PDF

PARASITOLOGY  EPIDEMIOLOGY I. Factors affecting Prevalence of Parasitic Infections Increased population density Poor sanitation Marginal water sources Poor public health practices Environmental changes affecting vector breeding areas Habits and...

PARASITOLOGY  EPIDEMIOLOGY I. Factors affecting Prevalence of Parasitic Infections Increased population density Poor sanitation Marginal water sources Poor public health practices Environmental changes affecting vector breeding areas Habits and customs of the people  EPIDEMIOLOGY II. Populations at Risk for Contracting Parasites Individuals in underdeveloped areas and countries Refugees Immigrants Visitors from foreign countries Immunocompromised individuals Individuals living in close quarters Children who attend day care centers  Specimen Collection and Handling Liquid specimen- examined within 30 minutes (trophozoite) Soft/semiformed- examined within 1 hour (trophozoite and/or cyst) Formed- may be examined within 24 hours  MODE OF TRANSMISSION 1. Soil-transmitted parasites 2. Snail-transmitted parasites 3. Food/drink-transmitted parasites 4. Contact-transmitted parasites 5. Vector-transmitted parasites 6. Congenital/Placental 7. Autoinfection  1. Soil-transmitted parasites “HATS” -developed further in the soil before they become infective Hookworms Ascaris lumbricoides Trichuris trichiura Strongyloides stercoralis  2. Snail-transmitted parasites -developed further in the body of the snail Definitive host: Man Intermediate host: Snail Flukes/Trematodes  3. Food/Drink-transmitted parasites -developed in the flesh of animals that man utilized as source of food or through drinking of contaminated water Taenia solium Taenia saginata Taenia spiralis Toxoplasma gondii Diphyllobothrium latum Entamoeba histolytica, Giardia lamblia, Cryptosporidium parvum  4. Contact- transmitted parasites - does not develop any further because they happen to be readily infective Enterobius vermicularis Trichomonas vaginalis  5. Vector-transmitted parasites -developed in the body of arthropods before they become infective Malaria Filaria Trypanosomes Leishmania  6. Congenital/Placental- transmitted parasites Toxoplasma Malaria Trypanosome  7. Autoinfection “CHEST” Capillaria philippinensis Hymenolepis nana Enterobius vermicularis Strongyloides stercoralis Taenia solium  NEMATODES Elongated, cylindrical in shape with bilateral symmetry Has sensory in anterior end (amphids) and posterior end (phasmids) Categories: Intestinal Nematodes Blood and Tissue Nematodes (Filariae)  I. Intestinal Nematodes Ascaris lumbricoides Other names: Giant intestinal roundworm, lumbricus teres, Eenworm Largest intestinal nematode Most common intestinal nematode in the tropics MOT: Ingestion Final/Definitive Host: Man Diagnostic stage: ova, adult Infective stage: embryonated egg  I. Intestinal Nematodes Ascaris lumbricoides Other names: Giant intestinal roundworm, lumbricus teres eenworm Belongs to the unholy three “HAT” Member of the larval heart-to-lung migration “ASH” Pathology: Visceral Larval Migrans (VLM) Ascaris pneumonitis or Loeffler’s syndrome Appendicitis Malnutrition  I. Intestinal Nematodes Trichuris trichiura Other name: Whipworm 3rd most common helminth MOT: Ingestion FH: Man Diagnostic stage: ova Infective stage: embryonated egg  I. Intestinal Nematodes Trichuris trichiura Other name: Whipworm Belongs to the unholy three “HAT” Pathology: IDA Rectal prolapse Blood and mucoid diarrhea  I. Intestinal Nematodes Capillaria philippinensis Other names: Pudoc worm, Mystery worm Close relative of Trichuris trichiura MOT: Ingestion Diagnostic stage: ova/larva Infective stage: filariform larva in IH Final host: Man Intermediate host: glass fishes Pathology: Borborygmi Malabsorption  I. Intestinal Nematodes Capillaria philippinensis vs. Trichuris trichiura C. philippinensis T. trichiura Size Smaller Larger Shell Striated Not striated Shape Peanut/guitar Football/barrel/Japanese lantern/lemon Mucus plugs Flattened bipolar plugs Prominent  I. Intestinal Nematodes Enterobius vermicularis Other names: Pinworm, seatworm, society worm Most common nematode in the world MOT: Ingestion and inhalation or airborne FH: Man Diagnostic stage: ova and adult Infective stage: embryonated egg  I. Intestinal Nematodes Enterobius vermicularis Other names: Pinworm, seatworm, society worm One of the parasites that may cause autoinfection “CHEST” Pathology: Pruritus ani/nocturnal pruritis Hemorrhagic colitis Autoinfection (external)  I. Intestinal Nematodes Hookworms The second most common helminthic infection- worldwide in distribution with 2 species infecting humans Infective stage: 3rd stage of filariform larva Pathology: Ground/Dew itch (Mazza mora/Water sore) Wakana fever Cutaneous larval migrans (CLM) IDA  I. Intestinal Nematodes Hookworms Human hookworms Animal hookworms N. americanus A. duodenale A. caninum A. braziliense Other names American hookworm, Old world Dog hookworm Cat hookworm American murderer, hookworm New world hookworm Buccal cavity w/ semilunar cutting 2 pairs of teeth 3 pairs of teeth 2 pairs of teeth plates Shape S-shaped C-shaped Male Copulatory Bipartite (barbed & Tripartite (simple) bursa bristle-like)  I. Intestinal Nematodes Strongyloides stercoralis Other name: Threadworm Smallest nematode infecting man #1 nematode commonly isolated in immunocompromised host MOT: Penetration Diagnostic stage: 1st stage of rhabditiform larva Infective stage: 3rd stage of filariform larva  I. Intestinal Nematodes Strongyloides stercoralis Other name: Threadworm One of the parasites that may cause autoinfection “CHEST” Pathology: Autoinfection (internal) Cochin China/Vietnam diarrhea  I. Intestinal Nematodes Hookworm vs. Strongyloides stercoralis Rhabditiform larva Hookworm S. stercoralis Buccal cavity Long Short Genital primordium Not prominent Prominent  I. Intestinal Nematodes Hookworm vs. Strongyloides stercoralis Filariform larva Hookworm S. stercoralis Length of esophagus Short Long Tail Pointed Notched  I. Intestinal Nematodes Trichinella spiralis Other names: Trichina worm, Muscle worm, Garbage worm Final/intermediate host: pig, rat, man Diagnostic/infective stage: encysted larva Habitat: larva- skeletal muscle Adult- small intestine Pathology: Eosinophilia Diarrhea and abdominal pain  II. Blood & Tissue Nematodes MOT: bite of infected arthropod Intermediate host: arthropods (vector-borne) Final host: man Diagnostic stage: microfilariae Infective stage: L3 larva Habitat: Lymphatics: W. bancrofti (lower), B. malayi (upper) Subcutaneous tissue: L. loa, O. volvulus Blood: all microfilaria except O. volvulus  II. Blood & Tissue Nematodes Wuchereria bancrofti Brugia malayi Loa loa Onchocerca volvulus Other Bancroft’s filaria Malayan filaria African eye worm Blinding filaria, River name/s blindness worm Vector Aedes, Culex, Aedes, Anopheles, Mansonia Chrysops sp. Simulium sp. Anopheles Mango/fruit fly Black fly Specimen Blood Blood Blood Skin snips/skin biopsies Periodicity Nocturnal Nocturnal Diurnal Nonperiodic  TREMATODES MOT: Oral except Schistosomes Infective stage: metacercaria except for Schistosomes (cercaria) 2 intermediate hosts except for Schistosomes (only 1) Categories: Blood Flukes Lung Fluke Intestinal Flukes Liver Flukes  I. Blood Flukes S. japonicum S. mansoni S. haematobium Other name/s Oriental blood fluke Manson’s blood fluke Vesical/bladder fluke Habitat Superior mesenteric vein Inferior mesenteric vein of Vesical/ urinary plexus of small intestine small intestine near urinary bladder Intermediate host Snail Infective stage Fork-tailed cercaria MOT Skin penetration Swimmer’s itch tail removed (schistosomule) Egg Smallest blood fluke egg Other notes Oriental schistosomiasis or Smallest blood fluke adult Urinary bilharziasis Katayama fever intestinal bilharziasis Egyptian hematuria  II. Lung Fluke Paragonimus westermani Other name: Oriental lung fluke Habitat: Lungs Final host: Sheep 1st IH: Snails 2nd IH: Crabs Infective stage: metacercaria MOT: Ingestion of 2nd IH  III. Intestinal Flukes Fasciolopsis buski Echinostoma ilocanum Heterophyes heterophyes Other name/s Giant intestinal fluke Garrison’s fluke Von Siebold’s fluke, Heterophid fluke Final host Man 1st IH Snail 2nd IH Freshwater plants Snail Crabs, crayfish Infective stage Metacercaria MOT Ingestion of 2nd IH Other notes Largest fluke Seen in bilibid prison Smallest but deadliest fluke  IV. Liver Flukes Fasciola hepatica Fasciola gigantica Clonorchis sinensis Opistorchis felineus Other name/s Temperate/Sheep Tropical/Giant liver Chinese/Oriental liver Cat liver fluke Liver fluke fluke fluke Final Host Sheep Cattle/water buffalo Man Cat 1st IH Snails 2nd IH Freshwater plants Fish Infective stage Metacercaria MOT Ingestion of 2nd IH Other notes Sheep liver rot Dominant in the Most important liver Philippines fluke in man END  CESTODES Adult tapeworm is flat and ribbon-like Hermaphroditic MOT: Ingestion The body consists of the following: Scolex – anterior attachment organ Neck- region of growth, starts segmentation Chain of segments or proglottids  Cestodes Taenia spp. Taenia solium Taenia saginata Other name/s Pork tapeworm Beef tapeworm Habitat Small intestine Final Host Man IH Pig Cattle Infective stage Cysticercus cellulosae larvae & Cysticercus bovis embryonated egg MOT Ingestion of measly pork and Ingestion of uncooked/raw beef embryonated egg  Cestodes Hymenolepis spp. Hymenolepis nana Hymenolepis diminuta Other name/s Dwarf tapeworm Rat tapeworm Habitat Small intestine Final Host Man Rat MOT Ingestion of embryonated and/or Ingestion of 2nd IH cysticercoid larvae Other notes Smallest and most common tapeworm Eggs have a sunny side up/fried egg of man appearance  Cestodes Dipylidium caninum Other names: Dog, double-pored or flea tapeworm The only parasite with two sets of reproductive organs Common tapeworm of the dog and cat MOT: Ingestion of flea FH: Dog/man IH: Dog/cat/human flea Infective stage: Cysticercoid  Cestodes Echinococcus granulosus Other name: Hydatid worm Causes Hydatid disease MOT: Ingestion of egg which develops into hydatid cyst Final Host: Dog or fox Intermediate host: Sheep/ox, goat, horse, camel Accidental host: Man Infective stage: Hydatid cyst/ embryonated ova Egg resembles Taenia spp.  Cestodes Diphyllobothrium latum Other name: Broad/fish tapeworm Largest tapeworm of man MOT: Ingestion of 2nd IH Final Host: Man 1st IH: Copepods (cyclops) 2nd IH: Freshwater fish (small fish) Infective stage: Plerocercoid larvae Egg resembles Paragonimus: adult resembles Spirometra  Protozoa Amoebae Types of Amoebae: True amoeba: Entamoeba –possesses peripheral chromatin (both cyst and trophozite) and chromatoidal bodies (cyst only) Other amoeba: Endolimax and Iodamoeba Locomotion: pseudopods (false-feet) MOT: fecal-oral (ingestion of infective cyst) All members have cystic stage and inhabit the large intestine except Entamoeba gingivalis All members are commensals except Entamoeba histolytica  Protozoa Amoebae Trophozoite Cyst Motile Non-motile Feeding stage Non-feeding stage Delicate and fragile Resistant Vegetative stage Infective stage Liquid/diarrheal stool Formed stool Examined within 30mins of passage Examined within 24hrs  Protozoa: Amoebae Entamoeba histolytica the only pathogenic amoeba; with unidirectional and progressive motility; only amoeba that ingests RBCs Entamoeba coli Ingests bacteria, sluggish motility Entamoeba dispar Morphologically similar to and reported along E. histolytica- don’t have RBCs (reporting: E. histolytica/E. dispar) Entamoeba hartmanni Known as the small-raced E. histolytica- don’t have RBCs Entamoeba polecki Uninucleate just like I. butschlii with angular or pointed chromatoidal bars in the cystic stage; resembles E. coli Parasite of pigs and monkeys Entamoeba gingivalis No cystic stage; only amoeba that ingests WBCs First parasitic amoeba discovered Can be found in the mouth  Protozoa: Free-living Amoebae Naegleria fowleri The brain-eating amoeba MOT: inhalation/aspiration of water, dust, or aerosols with the trophozoites or cysts Major causative agent of Primary Amoebic Meningoencephalitis (PAM) Able to survive at 46 ˚C and hyperchlorinated water  Protozoa: Free-living Amoebae Acanthamoeba spp. MOT: inhalation or direct entry through eyes (contact lens), ulcerations, mucosa and broken skin Major causative agent of Granulomatous Amoebic Encephalitis (GAE) and Acanthamoeba Keratitis (soft contact lenses)  Protozoa Flagellates Locomotion: flagella and axonemes Flagellates without cystic stage have more resistant trophozoite stage All members have trophozoites and inhabit the intestine except Trichomonas tenax and Trichomonas vaginalis  Protozoa: Flagellates Giardia lamblia Other names: Giardia intestinalis, G. duodenalis, Lamblia duodenalis, L. intestinalis Most common cause of intestinal infection worldwide and the most common protozoan pathogen The only pathogenic intestinal flagellate MOT: ingestion of contaminated food and water with cysts, person-to- person contact through oral-anal sexual practices, fecal-oral route Attachment: via an adhesive sucking disk causing mechanical irritation Troph: bilaterally symmetrical and similar to an old man’s face/old man with glasses/ old man with whiskers/monkey’s face/someone looking at you  Protozoa: Flagellates Dientamoeba fragilis Hakansson phenomenon Transmitted via the eggs of A. lumbricoides and E. vermicularis No cystic stage Chilomastix mesnili Cytostome fibril resembles shepherd’s crook (troph and cyst) Cyst: Lemon/pear-shaped with clear, anterior hyaline knob, resembling a nipple Retortamonas intestinalis Cytostome fibril: cleft-llike (trophozoite); bird’s beak (cyst) Cyst: Lemon/pear-shaped  Protozoa: Flagellates Trichomonas spp. T. hominis T. tenax T. vaginalis Habitat Intestine Mouth Genitalia Size Medium Smallest Largest Undulating membrane As long as the body 2/3 of the body ½ of the body Motility Nervous jerky Rapid jerky Inclusion bodies None Siderophile granules MOT Contaminated milk Kissing or use of Sexual intercourse contaminated utensils Other notes The only pathogenic member and most common parasite in urine; Trichomoniasis/ Ping-pong disease  Protozoa: Blood and Tissue Flagellates Trypanosoma cruzi Causative agent of Chaga’s disease/ American trypanosomiasis Vector: kissing/reduviid bugs, triatomine bugs Infective stage: metacyclic trypomastigote Diagnostic stage: trypomastigote Trypanosoma brucei gambiense Gambian/West African sleeping sickness Trypanosoma brucei rhodesiense Rhodesian/ East African sleeping sickness Vector: Glossina (tsetse fly) Infective stage: metacyclic trypomastigote Diagnostic stage: trypomastigote Leishmania Infective stage: promastigote Diagnostic stage: amastigote Vector: Phlebotomus (sandfly)  Protozoa: Ciliates Balantidium coli MOT: ingestion of pig stools DH: pig Infective stage: cyst Largest protozoan parasite Tissue invader because of the lytic enzyme (hyaluronidase) in the cilia BIOCHEMICAL TESTING: Gram Positive Cocci GUASA, JT Staphylococcus & Micrococcus  BIOCHEMICAL TESTING Gram stain Gram + cocci Catalase test Catalase (+) Catalase (–) Staphylococcus/Micrococcus Streptococcus/Enterococcus  BIOCHEMICAL TESTING Catalase test PURPOSE: Detects the presence of catalase (bacterial peroxidase) REAGENT: 3% Hydrogen peroxide (H2O2) PRINCIPLE: Catalase H2O2 H2O + O2 (+) effervescence Left: Positive – effervescence Right: Negative – no or few bubbles  BIOCHEMICAL TESTING Staphylococcus/Micrococcus O/F Glucose Modified Oxidase Bacitracin susceptibility Oxidative Fermentative Oxidase (+) Oxidase (–) Susceptible Resistant Micrococcus Staphylococcus  BIOCHEMICAL TESTING Oxidation/Fermentation (Hugh-Leifson) test PURPOSE: Determines whether an organism utilizes carbohydrates anaerobically (fermentation) or aerobically (oxidation) INDICATORS: Phenol red or Bromthymol blue CARBOHYDRATE: Any single sugar PRINCIPLE: Oxidation Carbohydrate Acid (+ gas) yellow color Fermentation  BIOCHEMICAL TESTING Oxidation/Fermentation test Sterile mineral oil, melted petrolatum, paraffin oil 1 2 3 1. Fermenter & oxidizer Aerobic Anaerobic 2. Nonfermenter – Oxidizer 3. Nonfermenter/non-oxidizer – Non-utilizer  BIOCHEMICAL TESTING Modified oxidase test PURPOSE: Detects the presence of cytochrome oxidase PRINCIPLE: Cytochrome Tetramethyl-p-phenylenediamine dihydrochloride oxidase Indophenol (blue to purple-blue) with Dimethyl sulfoxide (DMSO) Left: Positive – development of blue to purple-blue color within 2 min Right: Negative – absence of color  BIOCHEMICAL TESTING Bacitracin susceptibility test PURPOSE: Determines susceptibility/resistance to Bacitracin (0.04 Units) PROCEDURE: Aseptically place 37 °C Inoculate suspect Observe for zone of Bacitracin (Taxo A) disc organism on BAP inhibition (0.04 Units) Left: Susceptible – Any zone of inhibition (>6 mm diameter) Right: Resistant – No zone of inhibition  BIOCHEMICAL TESTING Staphylococcus Slide coagulase test Coagulase (+) Coagulase (–) Staphylococcus aureus S. Aureus & CNS Tube coagulase test Coagulase (+) Coagulase (–) Staphylococcus aureus CNS  BIOCHEMICAL TESTING Slide coagulase test PURPOSE: Detects the presence of cell-bound coagulase/clumping factor PRINCIPLE: Clumping factor Fibrinogen (plasma) Fibrin clot formation Rabbit plasma Left: Positive – Clumping Right: Negative – Smooth suspension  BIOCHEMICAL TESTING Tube coagulase test PURPOSE: Detects the presence of free coagulase/staphylocoagulase PRINCIPLE: Coagulase + Coagulase-reacting factor (CRF) Coagulase-CRF complex Fibrinogen (plasma) Fibrin clot formation Rabbit/human/pig plasma Left: Positive – Clot of any size Right: Negative – Smooth suspension  BIOCHEMICAL TESTING Coagulase Negative Staphylococci (CNS) Novobiocin susceptibility Resistant Sensitive Staphylococcus saprophyticus Other CNS Polymyxin B susceptibility Resistant Sensitive Staphylococcus epidermidis Other CNS  BIOCHEMICAL TESTING Novobiocin susceptibility test PURPOSE: Determines susceptibility/resistance to Novobiocin (5 μg) PROCEDURE: Aseptically place 37 °C Inoculate suspect Observe for zone of Novobiocin disc organism on MHA inhibition (5 μg) Left: Susceptible – >16 mm diameter Right: Resistant – ≤16 mm diameter  BIOCHEMICAL TESTING Polymyxin B susceptibility test PURPOSE: Determines susceptibility/resistance to Polymyxin B PROCEDURE: 37 °C Inoculate suspect Aseptically place Observe for zone of organism on MHA Polymyxin B disc inhibition Left: Susceptible – >10 mm diameter Right: Resistant – ≤10 mm diameter  BIOCHEMICAL TESTING Mannitol Salt Agar (MSA) PURPOSE: Used for the recovery and identification of staphylococci INHIBITORS: 7.5% NaCl (High salt concentration) INDICATOR: pH – Phenol red Mannitol Salt Agar CARBOHYDRATE: Mannitol Yellow 1 Mannitol fermenter S. aureus & S. saprophyticus 1 Red/colorless 2 2 Non-mannitol fermenter S. epidermidis & Micrococcus spp. Streptococcus & Enterococcus  BIOCHEMICAL TESTING Classification Species Lancefield Antigen Hemolysis type(s) Common terms S. pyogenes A β* Group A strep S. agalactiae B β* Group B strep S. dysgalactiae, C β Group C strep S. equi S. bovis group D α, none Nonenterococcus, viridans strep E. faecalis, D α, β, none Enterococcus E. faecium *Occasional non-hemolytic isolates found Lancefield antigen – C carbohydrate in the cell wall  BIOCHEMICAL TESTING Classification Species Lancefield Antigen Hemolysis type(s) Common terms S. pneumoniae – α Pneumococcus S. anginosus group, A, C, F, G, N, or – α, β, none Viridans strep S. mutans group, S. mitis group, S. salivarius group  Streptococccus agalactiae Important in OB/GYN patients where 25% of all females carry it as a normal vaginal flora Causes neonatal sepsis obtained during birth, neonatal meningitis, postpartum fever, osteomyelitis and wound infections Can colonize the urogenital tract of a pregnant woman Early onset infection – occurs in neonates who are less than 7 days old. Vertical transmission of the organism from the mother. Manifest in the form of pneumonia or meningitis with bacteremia Biochemical reactions Grayish white, mucoid, creamy colonies Catalase negative Bacitracin resistant Bile esculin negative Hippurate Hydrolysis test positive CAMP test positive Group D streptococcus and Enterococcus species Members of the gut flora Associated with bacteremia, Urinary tract infections, wound infections and endocarditis Enteroccoci – two known species ( E.faecalis and E.faecium) classic opportunists that show only low levels of pathogenicity. However, they are frequently isolated as components of a mixed flora in nosocomial infections. Often associated with endocarditis. Biochemical reactions Gray to white translucent colonies 6.5% NaCL – positive for Enterococcus species, negative for Group D streptococcus PYR Hydrolysis test - positive for Enterococcus species, negative for Group D streptococcus Bile Esculin Hydrolysis test – ability to grow in 40% bile and hydrolyze esculin Viridans streptococcus Alpha hemolytic Anaerobic to microaerophilic Agent of dental caries – attach to the proteins covering the tooth enamel where they then convert sucrose into extracellular polysaccharides The final metabolites of numerous plaque bacteria are organic acids that breach the enamel allowing different caries and bacteria to begin destroying the dentin Bile esculin test – negative Optochin resistant. Streptococcus pneumoniae Gram positive diplococci Lancet or bullet shaped Inhabits the nasopharyngeal areas of healthy individuals Causes Lobar pneumonia in elderly and alcoholics (rusty sputum) Otitis media and Meningitis in children however vaccine is now readily available Community acquired bacterial pneumonia Biochemical reactions Mucoid colonies Alpha hemolysis Optochin susceptibility test – SENSITIVE Bile solubility test – lyses in a suspension on sodium deoxycholate  BIOCHEMICAL TESTING Gram stain Gram + cocci Catalase test Catalase (+) Catalase (–) Staphylococcus/Micrococcus Streptococcus/Enterococcus  BIOCHEMICAL TESTING Streptococcus/Enterococcus Hemolytic pattern on S-BAP β-Hemolysis α-Hemolysis γ-Hemolysis Complete hemolysis Partial/Incomplete hemolysis No hemolysis  BIOCHEMICAL TESTING β-Hemolysis Complete hemolysis PYR hydrolysis Bacitracin susceptibility PYR (+) PYR (–) Sensitive Resistant Streptococcus pyogenes Group A Hippurate hydrolysis CAMP Test  BIOCHEMICAL TESTING PYR Hydrolysis test PURPOSE: Detects the presence of L-pyrrolidonyl arylamidase PRINCIPLE: L-pyrrolidonyl L-pyrrolidonyl- arylamidase α-naphthylamine + DMCA Red color α-naphthylamide (PYR) DMCA: p-dimethylaminocinnamaldehyde Positive – development of a bright red color within 5 min Negative – absence of color/orange color  BIOCHEMICAL TESTING Hippurate hydrolysis test PURPOSE: Detects the presence of Hippuricase REAGENT: Ninhydrin PRINCIPLE: Hippuricase NH3 + hydrindantin Sodium benzoate + Hippurate + Ninhydrin glycine + Ninhydrin (residual) Deep purple complex Left: Positive – Deep purple color Right: Negative – absence of color/slight purple or yellow-pink color  BIOCHEMICAL TESTING Hippurate hydrolysis CAMP Test Hippurate (+) Hippurate (–) CAMP (+) CAMP (–) Streptococcus agalactiae Group B Bile Esculin Bile Esculin (+) Bile Esculin (–) β-Hemolytic streptococci PYR hydrolysis Not group A, B, or D 6.5% NaCl  BIOCHEMICAL TESTING CAMP test PURPOSE: Detects CAMP (Christie, Atkins, and Munch-Peterson) factor PRINCIPLE: Staphylococcal β-lysin + CAMP factor 37 °C, CO2 Arrowhead hemolysis (Staphylococcus aureus) (enhanced hemolysis) Suspect organisms Left: Positive – Arrowhead hemolysis Right: Negative – No enhanced hemolysis Staphylococcus aureus  BIOCHEMICAL TESTING Bile esculin hydrolysis PURPOSE: Determines the ability to hydrolize esculin INHIBITOR: 4% Bile salts PRINCIPLE: Hydrolysis Black Esculin Glucose + esculetin + Ferric ammonium citrate) precipitate Left: Positive – Blackening Right: Negative – No color change  BIOCHEMICAL TESTING PYR hydrolysis 6.5% NaCl PYR (+) PYR (–) 6.5% NaCl (+) 6.5% NaCl (–) Enterococcus spp. Streptococcus spp. Group D Group D  BIOCHEMICAL TESTING Salt tolerance test PURPOSE: Determines the ability to grow in high salt concentration INHIBITOR: 6.5% NaCl PROCEDURE: Inoculate suspect organism 37 °C Observe for growth on BHIB (with 6.5% NaCl) (turbidity) Left: Positive – Presence of growth (turbid) Right: Negative – Absence of growth (clear)  BIOCHEMICAL TESTING α-Hemolysis Partial/incomplete hemolysis Optochin susceptibility Bile solubility Sensitive Resistant Bile soluble Bile Insoluble Streptococcus pneumoniae Bile esculin hydrolysis  BIOCHEMICAL TESTING Optochin susceptibility test PURPOSE: Determines susceptibility/resistance to Optochin PROCEDURE: 37 °C, CO2 Inoculate suspect Aseptically place Observe for zone of organism on BAP Optochin (Taxo P) disc inhibition Optochin: Ethylhydrocupreine hydrochloride Left: Susceptible – >14 mm diameter Right: Resistant – No zone of inhibition NOTE: Zone