| Question | Answer |
| Cocci bacteria arrangements: | diplococci - paired,
staphylococci - grape-clusters,
streptococci - chains |
| Some pathogenic cocci include: | Staphylococcus aureus (TSS),
streptococcus pneumonia, Neisseria gonorrhea,
Neisseria meningitidis,
methicillin-resistant staph aureus |
| Bacilli bacteria | Rod-shaped bacteria;
pathogenic: Clostridium tetani,
C. botulinum, C. difficile,
C. perfringens (food poisoning),
bacillus anthracis |
| Coccobacilli bacteria | Rod-shaped, short & wide bacteria;
pathogenic: Hemophilus influenza,
Chlamydia trachomatis |
| Gram-negative bacteria: | Don't stain;
Salmonella, Shigella dysenteriae,
E. coli, Pseudomonas aeruginosa (pneumonia, UTI),
N. meningitidis, N. gonorroeae, S. aureus |
| Gram-positive bacteria: | Stain blue due to cell wall of teichoic acid,
include - Clostridium botulinum, C. tetani,
Corynebacterium diptheriae, Actinomyces |
| Spirochetes are: | Spiral/corkscrew bacteria;
pathogenic: Leptospira (Weil's disease),
Triponema pallidium (syphilis),
Borrelia burgdorferi (Lyme disease),
argyrophil stains |
| Some bacteria types that don't have typical bacterial attributes include: | Rickettsiae, mycoplasmas |
| Which bacteria can only reproduce w/i living host cell? | Rickettsiae & chlamydiae |
| Rickettsiae causes: | Rocky mountain spotted fever,
typhus, tick-borne diseases |
| Mycoplasmas: | Don't form cell walls,
can cause pneumonia, still birth, abortion |
| Which stains are commonly used to screen for the presence of bacteria? | Methylene blue, Giemsa |
| Mycosis is: | disease caused by fungi |
| Mycology is: | study of fungi |
| Molds are: | Filamentous fungi,
easy to see septate hyphae in Aspergillus fumigatus |
| Yeasts are: | Single round/oval "budding" cells,
Cryptococcus neoformans (meningitis) |
| Yeast-like fungi are: | Filamentous, reproduce by budding to
form pseudohyphae,
Candida albicans (yeast infection, thrush) |
| Dimorphic fungi: | Have yeast-like morphology at 37 °C,
filamentous morphology on artificial media @ 25°C,
Blastomyces dermatitidis,
Coccidioides immitis (Valley fever),
Histoplasma capsulatum |
| Viruses are: | Protein-coated RNA or DNA,
seen w/ EM,
may form cellular inclusions visible w/ light microscope,
e.g. Negri bodies of rabies & cytomegalovirus |
| Protozoans are: | Single-celled microorganisms,
psuedopods, flagella, or cilia,
Entamoeba histolytica, Giardia lamblia,
Toxoplasma gondii |
| Pneumocystis carinii: | aka Pneumocystis jirovecii,
used to be considered protozoan,
more closely related to yeast |
| Acid-fast bacteria are: | Mycobacteria, rod-shaped,
may exhibit filamentous growth,
cell walls have lots of lipids so once stained
resists acid decolorization,
Mycobacterium tuberculosis, mycobacterium leprae |
| Kinyoun & Ziehl-Neelsen stains facts | Detect presence of acid-fast mycobacteria,
10% NBF, no Carnoy,
QC: tissue w/ acid-fast organisms |
| Kinyoun stain solutions | Kinyoun Carbol-Fuchsin +
acid alcohol +
methylene blue |
| Kinyoun & Ziehl-Neelsen stain results | acid-fast bacteria: bright red -
background: light blue |
| When cutting slides to test for acid-fast bacteria must use: | Millipore filtered water in bath,
no tap or dH2O,
use negative control from same day/bath/microtome |
| Kinyoun Carbol-Fuchsin solution | basic fuchsin +
phenol crystals (enhance stain) +
95% +
filtered water
filter before use |
| Methylene blue solution | methylene blue +
95% +
H2O |
| Kinyoun vs. Ziehl-Neelsen Carbol-Fuchsin solutions | Kinyoun has more basic fuchsin
& phenol than Ziehl-Neelsen |
| Ziehl-Neelsen method solutions | Ziehl-Neelsen Carbol-Fuchsin +
acid alcohol +
methylene blue |
| Ziehl-Neelsen Carbol-Fuchsin solution | basic fuchsin +
phenol crystals +
100% +
filtered H2O
filter before use |
| Microwave Ziehl-Neelsen method solutions | Carbol-Fuchsin soln. +
acid alcohol +
methylene blue w/ acetic acid |
| Microwave Ziehl-Neelsen method results | acid-fast bacteria
(incl. mycobacterium avium intracellulare): red -
rbc: pink -
mast cells: blue -
other: pale blue |
| Carbol-Fuchsin solution | pararosaniline (basic fuchsin) +
phenol crystals +
isopropanol +
filtered H2O
filter before use |
| Fite stain facts | To detect presence of Mycobacterium leprae,
10% NBF, no Carnoy,
QC: section w/ leprosy organisms |
| Fite stain solutions | xylene-peanut oil +
acid alcohol +
Ziehl-Neelsen Carbol-Fuchsin soln. +
methylene blue w/ acetic acid |
| Fite stain results | M. leprae, acid-fast bacteria: bright red -
background: light blue |
| Xylene-peanut oil is used to: | Protect capsule of leprae organism from dissolving during deparaffinization |
| Microwave auramine-rhodamine fluorescence technique facts | To detect presence of Mycobacterium tuberculosis & acid-fast bacteria,
10% NBF
QC: section w/ acid-fast mycobacteria |
| Microwave auramine-rhodamine fluorescence technique solutions | auramine O-rhodamine B soln. +
acid alcohol (decolorize) +
Erichrome black T 0.3% (quench autofluorescence) |
| Microwave auramine-rhodamine fluorescence technique results | acid-fast bacteria: reddish-yellow fluorescence -
background:black |
| Auramine O-rhodamine B solution | auramine O (fluorescent dye) +
rhodamine B (fluorescent dye) +
glycerol +
phenol +
filtered H2O |
| Alcian yellow-T blue facts | To ID H. pylori,
no glyoxal
QC: tissue w/ H. pylori |
| Alcian yellow-T blue solutions | periodic acid (ox. cell wall) +
alcian yellow (stain mucin) +
T blue (stain wall) +
sodium metabisulfite |
| Alcian yellow-T blue results | H. pylori: deep blue -
mucin: yellow |
| Gram stains purpose | ID Gram+ & - bacteria,
QC: section w/ Gram +& - bacteria |
| Gram stains solutions | crystal violet (stain all bacteria) +
basic fuchsin (stain Gram -) +
Gram iodine (mordant) +
100% or acetone (diff.) +
tartrazine or picric acid-acetone soln. (counterstain)
if overdecolorize, Gram + no stain |
| Gram stains results | Gram + : purple -
Gram - : red |
| Brown-Hopps modification of Gram stain solutions | crystal violet in dH2O +
basic fuchsin +
Gram iodine +
Gallego solution +
picric acid-acetone |
| Brown-Hopps modification of Gram stain results | Gram + : blue -
Gram - : red -
background: yellow -
nuclei: light red |
| Gallego solution | formalin +
glacial acetic acid +
dH2O |
| Giemsa stains can demo: | Bacteria, rickettsias, Toxoplasma gondii |
| Modified Diff-Quik Giemsa Stain purpose | ID H. pylori,
QC: section w/ H. pylori,
Romanowsky-type |
| Modified Diff-Quik Giemsa Stain solutions | Diff-Quik soln. I +
Diff-Quik soln. II +
acetic acid water |
| Modified Diff-Quik Giemsa Stain results | H. pylori, nuclei: dark blue -
other bacteria: blue -
cytoplasm: pink |
| Hotchkiss-McManus PAS reaction, Gridley, & Grocott-methenamine-silver nitrate stains purpose | Demo fungi,
QC: section w/ fungi |
| Hotchkiss-McManus PAS reaction solutions | periodic acid +
Schiff reagent +
sulfurous rinse (remove excess leucofuchsin) +
fast green w/ acetic acid (or light green) |
| Hotchkiss-McManus PAS reaction results | fungi: rose -
background: green |
| Gridley stain solutions | chromic acid +
Schiff +
aldehyde fuchsin (reacts w/ Schiff like an aldehyde) +
metanil yellow |
| Gridley stain results | Mycelia, elastic fibers, mucin: deep purple -
conidia: deep rose to purple -
background: yellow |
| Grocott-methenamine-silver nitrate stain facts | 4-5 μm paraffin, 6 μm frozen,
QC: for Pneumocystis use Pneumocystis control,
use chemically clean glassware & nonmetallic forceps |
| Grocott-methenamine-silver nitrate stain solutions | chromic or periodic acid (ox. walls to aldehyes) +
methenamine-silver nitrate working +
gold chloride +
sodium bisulfite (remove acid) +
sodium thiosulfate +
light green w/ acetic acid |
| Grocott-methenamine-silver nitrate stain results | fungi: sharply delineated in black -
mucin: taupe to dark gray (if black, methenamine too hot) -
background: green |
| Microwave methenamine-silver nitrate procedure purpose | Best to demo on cytospin preps or frozen diagnosis Pneumocystis carinii |
| Microwave methenamine-silver nitrate procedure facts | cytospin prep fixed in 95%,
frozen fixed in 40% formaldehyde, 6 μm,
paraffin routine
QC: pneumatocyst for P. carinii,
fungi for fungi |
| Microwave methenamine-silver nitrate procedure solutions | chromic acid +
methenamine-silver nitrate working +
gold chloride +
sodium thiosulfate +
sodium bisulfate (clear) +
light green w/ acetic acid |
| Microwave methenamine-silver nitrate procedure results | fungi & P. carinii: black -
background: green |
| Methenamine-silver working solution | methenamine +
AgNO3 +
Borax +
dH2O |
| What stains can demo Crytococcus neoformans? | Mayer mucicarmine & alcian blue;
may demo Blastomyces dermatitidis &
Rhinosporidium seeberi |
| Warthin-Starry, microwave Warthin-Starry, & Dieterle purpose | Demo spirochetes, legionella,
QC: section w/ spirochetes or legionella |
| Warthin-Starry Technique solutions | AgNO3 2% w/ acidulated water +
AgNO3 w/ acidulated water, gelatin soln. & hydroquinone |
| Warthin-Starry Technique results | spirochetes, other bacteria: black -
background: pale yellow to light brown |
| Acidulated water | triple-distilled H2O +
citric acid
pH4.0 |
| Microwave Warthin-Starry Method solutions | glycine-acetic acid pH 4.2 +
silver nitrate-gelatin-hydroquinone developer w/ glycine-acetic acid |
| Microwave Warthin-Starry Method results | alipia felis (cat-scratch bacillus), legionella pneumophila,
nocardia asteroides, H. pylori: black -
nuclei, rbc: brown |
| Dieterle Method solutions | alcoholic uranyl nitrate +
alcoholic gum mastic (protect organism) +
AgNo3 +
developer +
formic acid |
| Dieterle Method results | spirochetes, bacteria: brown to black -
background: pale yellow or tan
Melanin, chromatin, formalin pigment, foreign materials may also stain brown to black |
| Dieterle developer solution | alcoholic gum mastic +
acetone +
hydroquinone +
pyridine +
sodium sulfite +
formaldehyde +
dH2O |
| Microwave Steiner & Steiner procedure purpose | Demo spirochetes, H. pylori, legionella
QC: section w/ what staining for |
| Microwave Steiner & Steiner procedure solutions | uranyl nitrate (sens.) +
AgNo3 +
gum mastic +
reducing soln. |
| Microwave Steiner & Steiner procedure results | Spirochetes, H. pylori, Legionella, other nonfilamentous bacteria - dark brown to black
background - light yellow |
| Microwave Steiner & Steiner reducing solution | gum mastic +
hydroquinone (red.) +
abs. alcohol |
| When staining for spirochetes avoid what? | Mercurial & chromate fixatives,
10% NBF preferred |
| Sulfurous rinse solution | HCl +
potassium metabisulfite +
dH2O |
| Argentaffin stains | Gomori methenamine-silver,
Grocott methenamine-silver,
Fontana Masson,
von Kossa |
| Argyrophil stains | Reticulin, Holmes,
Bielschowsky, Warthin-Starry,
Dieterle, Steiner & Steiner,
Grimelius, Churukian-Schenk |
| Sayeed's Stain purpose & reagents | Detect H. Pylori,
periodic acid + Schiff + Mayer's hemalum |
| Plasmodium parasites | Cause malaria which deposits pigment closely related to formalin pigment |
| Cryptosporidium | Protozoa, causes severe outbreaks of diarrhea among AIDS patients |
| Listeria monocytogenes | Cause rare form of meningitis,
stain variably with Gram stain,
appear as intracellular rods in "Chinese letter" formation |
| Ziehl-Neelson may also demonstrate | Lipofuscins if technique is modified to include heat and prolonged staining |
