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95 Cards in this Set
- Front
- Back
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Intestinal Protozoa
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Amoeba - Entamoeba histolytica
Flagellates (Diplomonads) - Giardia lamblia, Trichomonas vaginalis Ciliates - Balantidium coli Coccidia - Cryptosproidium sp. |
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Extraintestinal Protozoa (blood and tissue)
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Plasmodium - 4x species
Toxoplasma gondii - Trypanosomes - 2 x Leishmania - 3x Other amoeba - Naegleria fowleri |
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Nematodes (Roundworms)
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Enterobius vermicularis (pinworms)
Ascaris lumbricoides (roundworms) |
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Trematodes (Flukes)
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Schistosomes
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Cestodes
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Tapeworms
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Definitive host
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host the harbors the adult stage of a helminth or the sexual stages of a protozoan
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Intermediate host
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host the harbors the larval stage or asexual
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Fecal Samples
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Appropriate for intestinal parasites
Cryptosporidium, Entamoeba, Giardia, Ascaris, Trichuris, Strongyloides |
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collection and preservation
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Fecal samples should be tranported promptly, it this is impractical, then preservatives such as 10% formalin, polyvinyl alcohol, or sodium acetate-formalin should be used.
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Intestinal Protozoa
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Characterized by trophozoite and cyst stages
Trophozoites cause pathology; cysts are primarily involved in transmission |
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Entamboa histolytica
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Diarrhea, cramping, BLOODY stools with localized necrosis in the large intestine due to cytotoxin.
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Extraintestinal amebiasis
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necrosis can provide entry into blood stream.
Liver involvement common with absess formation, more in males than females! |
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Ent histo diag
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trophozoites rounded with a single dark nucleus that looks like an eye
cysts round with 1-4 nuclei |
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Commensal amoeba
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E. dispar is most important bc morpho indistinguishable from E. histolytica
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Giardia lamblia
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Giardiasis
Resistant to Cl- Malodorous, water diarrhea, cramping, and distention |
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Giardia diag
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Trophozoites stain turquoise to grey
Cysts: grey or yellow/amber colored |
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Cryptosporidium (coccidians)
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Cryptosporidiosis
Most common in children < 5 Resistant to Cl- Profuse, watery diarrhea, (severe in AIDS with TONS of water) Self-limiting |
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Cryptosporidum diag
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Oocysts do not stain well, use ACID FAST stain
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Isospora belli and Cyclospora cayetanensis
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Similar to cryptosporidium
Use ACID FAST |
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Balantidium coli
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Balantidiasis
a ciliate resembles amebiasis, diarrhea, abdominal pain, nausea, anorexia |
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Trichomonas vaginalis
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urogenital parasite
Sexual contact 50% have colpitis macularis (strawberry cervix) with patchy lesions of the cervix detection of mobile trophozoites |
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Toxoplasma gondii
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CATS!
Sexual repro happens in the intestines of cats, producing oocysts stable for extended periods SEE LIFECYCLE CHART |
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Acute Toxoplasmosis
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cervical lymphadenopathy, headaches, night sweats, chorioretinitis
HAITI Symptoms: altered mental status, choriretinitis |
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Acute congenital toxoplasmosis
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severe neuro abnormaltities, exposure at earlier gestation = spontaneous abortion
exposure at later = neuro probs |
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Toxoplasmosis path
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Tissue cysts and necrotic lesions
congenital = retinal foci that impair night vision |
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Toxo diag
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Increase IgG titer!!!
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Naegleria fowerii, Acanthamoeba sp
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Free living amoebae
Three forms: cyst, trophozoite, flagellated forms |
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Naegleria fowerii, Acanthamoeba sp
transmission |
N. fowleri via olfactory epithelium
Acanthoamboae enter via lower respiratory tract or broken skin |
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PAM
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primary amebic meningoencephalitis VERY SERIOUS mortality within 72 hours
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Amebic Keratitis
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Caused by acanthamoeba, corneal ulcers results from trauma or contact lens use
Granulomatous skin lesions are also seen. |
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Plasmodium!!
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people are infected through the bite of the ANOPHELES mosquito
Mosquito is the definitive host, where sexual repro happens |
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Plasmodium epi
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Most blacks of african origin are resistant to vivax malaria because they genetically lack the duffy antigens on RBCs that are required for P. vivax entry
Hetero for sickle cell are resistant to ALL forms |
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Plasmodium symptoms
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All symptoms are most severe with P. falciparum malaria.
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Plasmodium lifecycle
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Bite = transfers sporozoites to human
Migrate to liver = merozoites RBCs = lyse and some diff into gametocytes which are taken up by mosquitoes where they reproduce |
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Id of plasmodium
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Ring and schizont in falciparum!
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Pancytopenia
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lysis of red cells during paracite replication
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Organ failure in malaria
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causes blackwater fever where peeing dark due to excretion of hemoglobin caused by kidney malfunctions
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Trypanosomes
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African Trypanosomiasis
vector borne flagellated bloodstream pathogens, classified as kinetoplastids based on the presence of a DARK STAINING ORGANELLE (kinetoplast) |
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African sleeping sickness
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Vector is the Tsetse fly
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Trypansoma symptoms
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Three stages of the disease
Acute phase: Trypanosomal chancre Systemic phase: Fever, lymphnode enlargement, myalgia. Winterbottom's sign is an enlargement of posterior cervical lymph nodes WEST Generalized lymphadenopathy EAST CNS involvement: lethargy, tremors, headaches, wasting syndrome |
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Life cycle of Trypanosoma brucei
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Infectious form = metacyclic trypomastigote injected by tsetse. These become bloodstream trypomastigotes
In Fly: procylic trypomastigotes in foregut and epimastigotes in salivary glands. |
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Trypanosoma diag
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found in blood, lymph.
later stages = CSF T. brucei has very complex antigenic variation system |
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American trypanosomiasis
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Chagas Disease
caused by trypanosoma cruzi vector is the Reduviid. |
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Chagas life cycle
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Difference from brucei = amastigote stage, which penetrates tissues and divides INTRACELLULARLY by binary fission. `
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Chagas symptoms
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Acute: Chagoma at bite site, arises a week after infection, includes fever, lympadenopath,
Chronic: asymptomatic Symptomatic chronic: chagas disease, Cardiac enlargement, esophagus, mega colon. |
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Leishmania
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Vector is the sandfly and several rodent species are resevoirs
Primarily intracellular in the human host! |
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Cutaneous Leishmania
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Red papule at bite site 2 weeks/months after infection. Lesion ulcerates and becomes crusted and hyperpigmented.
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Leishmania Lifecycle
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promastigotes injected into SKIN.
Phagocytosed by macrophages and change into amastigotes, which divide intracellularly. Transfered back to sandfly |
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Mucocutaneous Leishmaniasis
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Espundia
caused by L. viannia braziliensis but can metatisize to mucosal surfaces, including the nasopharynx |
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Visceral Leishmaniasis
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Kala-azar or Dumdum fever
caused mainly by L. donovani Diag: K30 antigen in visceral disease |
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Babesia
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East coast by ticks
symptoms like malaria, related to plasmodium Generally larger, darker and sometimes form an x-shaped MALTESE cross |
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Enterobius vermicularis
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Fecal oral
Eggs hatch in small intestine and adults inhabit the cecum, appendix, and ascending colon. Adult females migrate out of the anus at night to deposit their eggs in perianal muscosa before retreating into the lower GI |
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Enterobius vermicularis
symptoms |
perianal itching
diarrhea SCOTCH TAPE, prior to bathing in the morning |
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Ascaris lumbricoides
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Acariasis
spread by fecal oral Symptoms are rare |
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Ascaris lumbricoides
LIFECYCLE |
Humans ingest eggs
Larvae develop in small intestine carried to heart, then lung coughed and reswallowed |
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Ascaris lumbricoides
Loeffler's syndrome |
during pulmonary migration, a pneumoinitis can occur called Loeffler's syndrome with coughing, dyspnea, and eosinophilia.
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Tricuris tichuria
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Trichuriasis
whipworm that lives in the colon |
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Tricuris trichuria
lifecycle |
Humans ingest eggs
Larvae in small intestine Develop into adults in colon eggs are excreted |
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Tricuris trichuria
Diag |
Eggs are slightly yellowish (bile-stained) with thick white caps on both ends.
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Hookworms
Ancyclostoma duodenale Necator americanus |
Ancyclostomiasis
soil with feces! penetrate skin! |
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Ancyclostoma duodenale
Necator americanus LIFE CYCLE |
eggs in feces, hatch into noninfective Rhabditiform larvae
Develop into filiariform larve which penetrate skin and migrate to the lungs cough and swallow |
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Ancyclostoma duodenale
Necator americanus symptoms! |
Hypochromic anemia with potential developmental retardation in malnourished children. Loefflers!
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Ancyclostoma duodenale
Necator americanus Diag |
Eggs are thin shelled, non bile stained
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Strongyloides stercoralis
LIFECYCLE |
Filariform larvae penetrate the skin, migrate to the lungs, and eventually reach the small intestine. Reproduce asexually and hatch rhabitiform in the colon, which can autoinfect.
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Strongyloides
symptomes |
Loeffler's!
Diarrhea, occulsion of pancreatic duct mistaken for peptic ulcer Can cause hyperinfection syndrome! q |
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Trichenella spiralis
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Trichinosis
Found in MEAT products! PORK! |
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Trichonosis
LIFECYCLE |
Ingest encysted larvae from muscle
Excystation occurs in small intestine, where larvae penetrate muscosae and develop into adults. Larvae migrate to striated muscles and form cysts |
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Trichonosis
Symptoms and Diag |
Fever, abdominal pain, myalgia, eosinophilia. Splinter hemorrhages under nails.
EOSINOPHILA and muscle biopsies to see encysted larvae |
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Visceral Larval Migrans
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Toxicariasis
Associated with contact with dogs and cats. Most are asymptomatic but can be rash, anorexia, hepatosplenomegaly. |
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Lymphatic Filariasis
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primarly infects lymphatic system, causing englargement of tissues.
Transmitted by MOSQUITOES! |
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Lympathic Filariasis
Life cycle |
Larvae transmitted through mosquito bites, migrate to the lymphatic system, and develop into adults.
Microfilariae are released AT night into the blood stream. |
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Onchocerca volvulus
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Onchocerciasis/ Riverblindness
Vector is the blackfly |
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Onchocerca volvulus
Symptoms |
Lifecycle similar to lymphatic filarisis with the exception of tissue preference of adult worms for the skin and eyes.
Dermatitis, skin nodules, and ocular lesions |
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Onchocerca volvulus
Diag |
Detection of microfilariae in skin snips or biopsies of nodules.
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Loa Loa
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Filariasis!
Vector is Chrysops fly. Microfilariae migrate to muscle, eye. Calabar swellings. |
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Dirofilaria immitis
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Dog heartworm!
Mosquite bites! Coin lesion in the lung |
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Dracululus medinensis
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Drink water with the Cyclops microcrustacean with larvae.
Larvae mature in perioneum and mate there. Fertilized females migrate to subcutaneous tissues and create an ulcer. Worm releases larvae into water upon contact through the ulcer. |
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Schistomiasis
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Snail Fever!
Blood flukes |
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Schistomiasis
Life cycle |
Eggs excreted in human feces or urine.
Miracidia penetrate snails. In snails sporocysts are formed followed by cercariae. Cercariae penetrate the skin and become schistosomulae.. |
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Blood site preferences
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S. mansoni - Inferior mesenteric veins
S. japonicum - Superior mesenteric veins S. hematobium - Urinary plexus and veins |
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Schisotomiasis
Acute |
Katayama's Fever
Fever, cough, abdominal pain, diarrhea. Rash at site of penetration. Liver granulomas! |
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Chronic Schistomiasis
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follow acute phase as adult worms continue to lay eggs.
Most of the symptoms arise from immuno responses to depositied eggs with granulomatious inflammatory responses, fibrosis and obstruction. |
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Swimmer's Itch
Schistomiasis |
Skin rash associated with larval penetration.
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Schistomiasis
Spine differences |
S. mansoni: Lateral spine
S. japonicium: NO SPINE S. hematobium: Terminal spine granulomas in skin biopsies |
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Paragoniumus westermani
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Lung fluke
Asia, Africa, Latin America Destruction of lung tissue produces 'rusty sputum' colored with blood and eggs |
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Fasciolopsis buski
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GI fluke
SE Asia abdominal pain and diarrhea |
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Fasciola hepatica
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Liver Fluke
heptomegaly, upper right quad pain, hepatitis and biliary obstruction can result from worms occluding bile duct. |
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Opisthrochis sinesis
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Chinese Liver Fluke
Freshwater fish via undercooked fish diarrhea, etc |
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Taenia saginata
Taenia solium |
T. solium- pork
T. saginata- beef eat contaminated pork or beef observation of proglottid segments in feces |
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Taenia saginata
Taenia solium LIFECYCLE |
Contaminated meat.
Adults develop in small intestine Self fertilzation and desegmentation. Eggs hatch and form oncosphere which migrates into tissues and is infective. |
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Cysticercosis
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occurs only with T. solium, ingestion of eggs rather than cysticerci can lead to hatching in the stomach, and migrates to muscles.
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Hydatidosis
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Echinococcosis
E. granulosus: cystic echinococcis E. multilocularis: alveloar echinococcis E. vogeli: polycystic echinococcosis |
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Hydatidosis
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Get if from dogs, wolves, etc.
Feces with eggs. Eggs hatch and form oncospheres which develop into cysts. Large, liters in volume. |
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Diphyllobothrium latum
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Fish tapeworm
Crustaceans B12 deficiency |
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Hymenolepsosis
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dwarf tapeworm
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