Parasitology

Plasmodium vivax

Widest distribution of malarial species

infect reticulocytes, larger than surrounding red cells, giant platelets are seen

Plasmodium vivax appearance in thin smear

ring form in RBC, heavy chromatin dot

Early trophozoite Plasmodium vivax

almost fills the entire RBC, fine golden brown pigment, some vacuoles, stippling

Late trophozoite Plasmodium vivax

division of chromatin, may contain clumps of brown

Early schizont Plasmodium vivax

12-24 merozoites, distinct cytoplasm and chromatin, fills entire RBC

late schizont Plasmodium vivax

golden brown pigment, large chromatin mass, rounded or oval with homogeneous cytoplasm

Gametocyte Plasmodium vivax

plasmodium ovale

Least common malarial species

infect reticulocytes, oval shape with fimbriation, stippling

Plasmodium ovale

Fing is more compact, prominent chromatin

early trophozoite plasmodium ovale

ring shape, vacuole, less ameboid activity, stippling present

Late trophozoite plasmodium ovale

medium, more compact, coarse

Early schizont plasmodium ovale

6-12 merozoites in rosettes or clusters

Late schizont plasmodium ovale

characteristic crescent shaped gametocytes, invade RBC or any age, in peripheral blood then capillaries during severe infections

Plasmodium falciparum

small ring with one or two small chromatin dots, cytoplasm around vacuoles

early trophozoite Plasmodium falciparum

heavier ring, rarely ameboid, granular

Late trophozoite Plasmodium falciparum

crescent

Trophozoite gametocyte Plasmodium falciparum

infect mature RBC

plasmodium malariae

small ring, heavy chromatin with compact cytoplasm, pigment develops early

early trophozoite plasmodium malariae

nonameboid, compact almost fill the host cell, band shaped

Late trophozoite plasmodium malariae

smaller, more compact, pigment granules are coarse

Early schizont plasmodium malariae

large merozoites in rosettes or irregular, pigment is arranged centrally

Late schizont plasmodium malariae

fewer in number, dark and coarse

Gametocyte plasmodium malariae

presence of tetrads, no trophozoites and gametocytes, no pigment

Babesia

flagellated protozoa which live in the blood stream and tissues. Transmitted by arthropod vectors. Has undulating membrane to make it motile

Trypanosomes

characterized by the C or U shape

Trypanosoma cruzi

curvy queens

Trypanosoma brucei gambiense and trypanosoma brucei rhodesiense

arthropod transmitted nematodes which reside in the lymphatics and other tissue sites

Filariae or threadworms

sheathed, nuclei that don't extend to the tip of the tail

Wuchereria broncrofti microfilariae

sheathed, two solitary nuclei, one nuclei extends to the tip of the tail

Brugia malayi microfilariae

sheathed, nuclei extends to the tip of the tail in a continuous row, the sheath does not stain showing a ghost image

Loa loa microfilariae

unsheathed, nuclei to the tip of the tail

mansonella perstans microfilariae

unsheathed, thin pointed tail without nuclei

Mansonella ozzardi microfilariae

Entamoeba histolytica

What causes amebic dysentery

single nucleus, evenly distributed chromatin and small karyosome

Trophozoite E. histolytica

spherical, mature cysts have four nuclei, immature have one or two

Cyst E. histolytica

single nucleus, chromatin is unevenly distributed, stains dark, numerous vacuoles

E. coli trophozoites

mature 8-16 nuclei, immature have fewer, glycogen may be present, irregular, splintered ends

E. coli cyst

single nucleus, small karysome, granular ring of chromatin

Trophozoite entamoeba hartmanni

small, contain four nuclei, immature one or two nuclei

entamoeba hartmanni cyst

single nucleus, small central karyosome, granular ring of chromatin, small size

Entamoeba harmanni trophozoite

mature have four nuclei, very small

Entamoeba hartmanni cyst

Large central karyosome, lacks peripheral chromatin. see a halo of muddy karyolymph

Iodamoeba butschlii trophozoite

single nucleus, compact mass of glycogen

Iodamoeba butshlii cyst

smallest ameba found in the human intestine, single nucleus, prominent karyosome, halo surrounds the karyosome

Endolimax nana trophozoite

four or fewer nuclei, centrally located karysomes surrounded by a small halo, glycogen diffusely in the cytoplasm

Endolimax nana cyst

spherical, large central vacuole and two or more peripheral nuclei

Central vacuolar form blastocystis hominis

highly irregular, crescent shaped nuclear chromatin

ameboid blastocystis hominis

bilaterally symmetrical, two nuclei with centrally located karyosomes, eight flagella

G. lamblia trophozoites

vary in size, oval, four nuclei, intracytoplasmic fibrils

G. lamila cysts

vary in size, ameboid in shape, two nuclei, nuclei often appear as clusters of small granules

D. fragillis trophozoites

vary in size, pear shaped, single nucleus with centrally located karyosome and a ring of finely granular peripheral chromatin, prominent cytosome extending one-third of the body

C. mesnili trophozoites

lemon shaped, one nucleus, vary in diameter, intra cytoplasmic fibrils

C. mesnili cysts