Difference between revisions of "Microorganisms"

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=Microorganisms=
=Microorganisms=
==Fungi==
==Fungi==
{| class="wikitable"
{| class="wikitable sortable"
|-
|-
! Name (disease)
! Name (disease)
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| ? Immunosuppression
| ? Immunosuppression
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| [http://commons.wikimedia.org/w/index.php?title=File:Pulmonary_aspergillosis.jpg Aspergillus (WC)], [http://commons.wikimedia.org/wiki/File:Pulmonary_aspergillosis_cytology.jpg Aspergillus cytology (WC)]
| [[Image:Pulmonary_aspergillosis.jpg|thumb|center|150px| Aspergillus. (WC)]]
|-
|-
| Zygomycota ([[zygomycosis]]);<br>''more specific''<br>Mucorales ([[mucormycosis]])
| Zygomycota ([[zygomycosis]]);<br>''more specific''<br>Mucorales (mucormycosis)
| Fungi
| Fungi
| ?
| ?
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| Diabetes, immunodeficient
| Diabetes, immunodeficient
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| [http://granuloma.homestead.com/ZygoHE_02.jpg Mucormycosis (homestead.com)], [http://commons.wikimedia.org/wiki/File:Zygomycosis.jpg Zygomycosis (WC)]
| [[Image:Zygomycosis.jpg |thumb|center|150px| Zygomycosis. (WC)]]
|-
|-
| Coccidioides, usually C. immitis<br>([[coccidioidomycosis]])
| Coccidioides, usually C. immitis<br>(coccidioidomycosis)
| Fungi
| Fungi
| '''Large''' - 20-60 micrometers,<br> endospores 1-5 micrometers
| '''Large''' - 20-60 micrometers,<br> endospores 1-5 micrometers
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| Immunodeficient
| Immunodeficient
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| [http://pathmicro.med.sc.edu/mycology/cocc3.jpg Coccidioidomycosis (med.sc.edu)] [http://commons.wikimedia.org/wiki/File:Coccidioides_immitis_on_Sabouraud%27s_medium.jpg C. immitis (WC)] [http://www.webpathology.com/image.asp?case=374&n=3 (webpathology.com)]
| [http://pathmicro.med.sc.edu/mycology/cocc3.jpg Coccidioidomycosis (med.sc.edu)] [[Image:Coccidioides_immitis_on_Sabouraud%27s_medium.jpg |thumb|center|150px|C. immitis (WC)]]  
|-
|-
| Histoplasma ([[histoplasmosis]])
| Histoplasma ([[histoplasmosis]])
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| Source: soil with bird droppings
| Source: soil with bird droppings
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| [http://commons.wikimedia.org/wiki/File:Histoplasma_pas-d.jpg Histoplasmosis (WC)]
| [[Image:Histoplasma_pas-d.jpg|thumb|center|150px| Histoplasmosis. (WC)]]
|-
|-
| Blastomyces ([[blastomycosis]])
| Blastomyces ([[blastomycosis]])
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| Habitat: Northeast America, Africa
| Habitat: Northeast America, Africa
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref><ref>[http://pathmicro.med.sc.edu/mycology/mycology-6.htm http://pathmicro.med.sc.edu/mycology/mycology-6.htm]</ref>
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref><ref>[http://pathmicro.med.sc.edu/mycology/mycology-6.htm http://pathmicro.med.sc.edu/mycology/mycology-6.htm]</ref>
| [http://pathmicro.med.sc.edu/mycology/blast1.jpg Blastomyces]
| [[Image:Blastomycosis_cropped.JPG | thumb|center|150px|Blastomyces. (WC)]]
|-
|-
| Paracoccidioides ([[paracoccidioidomycosis]])
| Paracoccidioides ([[paracoccidioidomycosis]])
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| Clinical???
| Clinical???
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| [http://commons.wikimedia.org/wiki/File:Paracoccidioides_brasiliensis_01.jpg P. brasiliensis (WC)].
| [[Image:Paracoccidioides_brasiliensis_01.jpg |thumb|center|150px|P. brasiliensis (WC)]]
|-
|-
| Pneumocystis jirovecii ([[pneumocystis pneumonia]]; abbrev. PCP)
| Pneumocystis jirovecii ([[pneumocystis carinii pneumonia]]; abbrev. PCP)
| Fungi (previously thought to be a protozoan)
| Fungi (previously thought to be a protozoan)
| 7-8 micrometres
| 7-8 micrometres
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| [[HIV]]/AIDS associated
| [[HIV]]/AIDS associated
| <ref name=Ref_APBR684>{{Ref APBR|684}}</ref>
| <ref name=Ref_APBR684>{{Ref APBR|684}}</ref>
| [http://commons.wikimedia.org/wiki/File:Pneumocystosis_carinii_of_lung_in_AIDS_959_lores.jpg PCP (WC)]
| [[Image:Pneumocystosis_carinii_of_lung_in_AIDS_959_lores.jpg|thumb|center|150px| PCP. (WC)]]
|-
|-
| Cryptococcus ([[cryptococcosis]])  
| Cryptococcus ([[cryptococcosis]])
| Fungi  
| Fungi  
| 5-15 micrometres
| 5-15 micrometres
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| HIV/AIDS associated, most common CNS fungus
| HIV/AIDS associated, most common CNS fungus
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| <ref name=Ref_APBR682>{{Ref APBR|682}}</ref>
| [http://commons.wikimedia.org/wiki/File:Cryptococcosis_of_lung_in_patient_with_AIDS_Methenamine_silver_stain_963_lores.jpg Crytococcosis - methenamine silver (WC)], [http://commons.wikimedia.org/wiki/File:Cryptococcosis_of_lung_in_patient_with_AIDS._Mucicarmine_stain_962_lores.jpg Crytococcosis - mucicarmine (WC)].
| [[Image:Cryptococcosis_of_lung_in_patient_with_AIDS._Mucicarmine_stain_962_lores.jpg |thumb|center|150px| Crytococcosis - mucicarmine (WC)]]
|}
|}
Notes:
Notes:
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* "Spike" approx. the size of a [[PMN]].  
* "Spike" approx. the size of a [[PMN]].  


Images:
====Images====
*[http://commons.wikimedia.org/wiki/File:Schistosomiasis_haematobia.jpg Schistosomiasis haematobia (WC)].
<gallery>
Image:Schistosomiasis_haematobia.jpg | Schistosomiasis haematobia. (WC)
Image:Schistosoma japonicum (1) histopathology.JPG | Schistosoma japonicum. (WC/KGH)
Image:Schistosoma japonicum (2) histopathology.JPG | Schistosoma japonicum. (WC/KGH)
Image:Schistosoma japonicum (3) histopathology.JPG | Schistosoma japonicum. (WC/KGH)
Image:Schistosoma_-_intermed_mag.jpg | Schistosoma eggs - intermed. mag. (WC/Nephron)
Image:Schistosoma_-_very_high_mag.jpg | Schistosoma eggs - very high mag. (WC/Nephron)
</gallery>
www:
*[http://path.upmc.edu/cases/case622.html Schistosomiasis - several images (upmc.edu)].
*[http://path.upmc.edu/cases/case622.html Schistosomiasis - several images (upmc.edu)].
*[http://path.upmc.edu/cases/case622/images/fig08.jpg Comparison of Schistosome eggs (upmc.edu/Lancet)].
*[http://path.upmc.edu/cases/case622/images/fig08.jpg Comparison of Schistosome eggs (upmc.edu/Lancet)].
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*Common CNS infection.
*Common CNS infection.
**''Toxoplasma gondii'' - pathogenic; causes ''toxoplasmosis''.
**''Toxoplasma gondii'' - pathogenic; causes ''toxoplasmosis''.
*Protozoa.
*Previously classified as a ''protozoa''.
*A [[TORCH infection]].
*A [[TORCH infection]].


===Microscopic===
===Microscopic===
General:
General:
*Dependent on location in body.
*Tachyzoites (Invasive form):
**Crescent-shaped organisms that are 2-3μm wide by 4-8μm long.
*Bradyzoites:
**Are founded within the tissue cysts and are shorter than tachyzoites.
*Oocysst:
**Ovoid shape that measures 10μm to 12μm and contains four sporozoites.
 
*Histopathological features depend on location in body.


====Lymph node====
====Lymph node====
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*Granular appearing ball ~ 2x the size of resting lymphocyte.
*Granular appearing ball ~ 2x the size of resting lymphocyte.


Images (CNS):
=====Images (CNS)=====
*[[WC]]:
<gallery>
**[http://commons.wikimedia.org/wiki/File:Toxoplasmosis_-_cropped_-_very_high_mag.jpg CNS toxoplasmosis - very high mag. (WC)].
Image:Toxoplasmosis_-_cropped_-_very_high_mag.jpg | CNS toxoplasmosis - very high mag. (WC)
**[http://commons.wikimedia.org/wiki/File:Toxoplasmosis_-_ihc_-_very_high_mag.jpg CNS toxoplasmosis - IHC - very high mag. (WC)].
Image:Toxoplasmosis_-_ihc_-_very_high_mag.jpg | CNS toxoplasmosis - IHC - very high mag. (WC)
*www:
</gallery>
**[http://moon.ouhsc.edu/kfung/jty1/opaq/PathQuiz/N0I001-PQ01-M.htm CNS toxoplasmosis (ouhsc.edu)].
www:
**[http://moon.ouhsc.edu/kfung/jty1/Composites/FND5IE01-Toxoplasmosis-Micro.htm CNS toxoplasmosis (ouhsc.edu)].
*[http://moon.ouhsc.edu/kfung/jty1/opaq/PathQuiz/N0I001-PQ01-M.htm CNS toxoplasmosis (ouhsc.edu)].
**[http://path.upmc.edu/cases/case350.html Toxoplasmosis - several images (upmc.edu)].
*[http://moon.ouhsc.edu/kfung/jty1/Composites/FND5IE01-Toxoplasmosis-Micro.htm CNS toxoplasmosis (ouhsc.edu)].
*[http://path.upmc.edu/cases/case350.html Toxoplasmosis - several images (upmc.edu)].


====Heart====
====Heart====
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*~10-15 micrometers wide.
*~10-15 micrometers wide.


Images:
====Images====
<gallery>
Image:Strongyloides_stercoralis_larva.jpg | Strongyloides. (WC)
</gallery>
www:
*[http://www.totallyfreeimages.com/121316/This-micrograph-reveals-adult-strongyloides-nematodes-located-am Strongyloides (CDC/totallyfreeimages.com)].
*[http://www.totallyfreeimages.com/121316/This-micrograph-reveals-adult-strongyloides-nematodes-located-am Strongyloides (CDC/totallyfreeimages.com)].
*[http://commons.wikimedia.org/wiki/File:Strongyloides_stercoralis_larva.jpg Strongyloides (WC)].
*[http://www.sciencephoto.com/media/116331/enlarge Strongyloides (sciencephoto.com)].
*[http://www.sciencephoto.com/media/116331/enlarge Strongyloides (sciencephoto.com)].


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*Classically found in a [[vermiform appendix]] removed for appendicitis that does not have [[acute appendicitis]].<ref name=pmid7945067>{{Cite journal  | last1 = Dahlstrom | first1 = JE. | last2 = Macarthur | first2 = EB. | title = Enterobius vermicularis: a possible cause of symptoms resembling appendicitis. | journal = Aust N Z J Surg | volume = 64 | issue = 10 | pages = 692-4 | month = Oct | year = 1994 | doi =  | PMID = 7945067 }}</ref>  
*Classically found in a [[vermiform appendix]] removed for appendicitis that does not have [[acute appendicitis]].<ref name=pmid7945067>{{Cite journal  | last1 = Dahlstrom | first1 = JE. | last2 = Macarthur | first2 = EB. | title = Enterobius vermicularis: a possible cause of symptoms resembling appendicitis. | journal = Aust N Z J Surg | volume = 64 | issue = 10 | pages = 692-4 | month = Oct | year = 1994 | doi =  | PMID = 7945067 }}</ref>  
**See: ''[[Vermiform appendix#Enterobius vermicularis]]''.
**See: ''[[Vermiform appendix#Enterobius vermicularis]]''.
===Gross===
*Peri-anal white squiggly thing ~ 2-13 mm in length.
Image:
*[http://www.dijitalimaj.com/alamyDetail.aspx?img={14157DA6-DBE8-4E03-BE4A-69591588E153} Pinworm (dijitalimaj.com)].


===Microscopic===
===Microscopic===
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*Characteristic triangular "spikes" seen on cross section - base x height ~ 30 x 30 μm.
*Characteristic triangular "spikes" seen on cross section - base x height ~ 30 x 30 μm.
**''Spikes'' is in quotations, as these are really a longitudinal blade-like ridges, that run the length of the worm.  
**''Spikes'' is in quotations, as these are really a longitudinal blade-like ridges, that run the length of the worm.  
Image:
*[http://commons.wikimedia.org/wiki/File:Pinworms_in_the_Appendix_%281%29.jpg Pinworm (WC)].


Features - eggs:<ref name=Ref_APBR685>{{Ref APBR|685}}</ref>  
Features - eggs:<ref name=Ref_APBR685>{{Ref APBR|685}}</ref>  
*Ovoid - double walled shells, one side flat.
*Ovoid - double walled shells, one side flat.


====Images====
www:
*[http://www.brown.edu/Courses/Digital_Path/systemic_path/GI/enterobius.html Enterobius (brown.edu)].
<gallery>
Image:Enterobius_-_very_low_mag.jpg | Enterobius - very low mag. (WC)
Image:Enterobius_-_high_mag.jpg | Enterobius - high mag. (WC)
Image:Pinworms_in_the_Appendix_%281%29.jpg | Pinworm (WC)
</gallery>
==Trichinella==
==Trichinella==
===General===
===General===
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*Caused by ''Taenia solium''; pork tapeworm.
*Caused by ''Taenia solium''; pork tapeworm.
*May cause [[epilepsy]]; most common parasitic CNS infection.<ref name=pmid19208982>{{cite journal |author=Prasad KN, Prasad A, Verma A, Singh AK |title=Human cysticercosis and Indian scenario: a review |journal=J. Biosci. |volume=33 |issue=4 |pages=571–82 |year=2008 |month=November |pmid=19208982 |doi= |url=}}</ref>
*May cause [[epilepsy]]; most common parasitic CNS infection.<ref name=pmid19208982>{{cite journal |author=Prasad KN, Prasad A, Verma A, Singh AK |title=Human cysticercosis and Indian scenario: a review |journal=J. Biosci. |volume=33 |issue=4 |pages=571–82 |year=2008 |month=November |pmid=19208982 |doi= |url=}}</ref>
===Gross===
*Multiple cystic spaces.
Image:
*[http://reference.medscape.com/features/slideshow/neurocysticercosis Neurocysticercosis (medscape.com)].


===Microscopic===
===Microscopic===
Line 281: Line 317:


Images:
Images:
*[http://www.dpd.cdc.gov/dpdx/html/imagelibrary/A-F/Cysticercosis/body_Cysticercosis_il1.htm Cysticercosis (cdc.gov)].
*[http://www.sciencephoto.com/media/116340/enlarge Cysticercosis (sciencephoto.com)].
*[http://path.upmc.edu/cases/case154.html Neurocysticercosis - case 1 (upmc.edu)].
*[http://path.upmc.edu/cases/case154.html Neurocysticercosis - case 1 (upmc.edu)].
*[http://path.upmc.edu/cases/case376.html Neurocysticercosis - case 2 (upmc.edu)].
*[http://path.upmc.edu/cases/case376.html Neurocysticercosis - case 2 (upmc.edu)].
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*Small ~1-2 micrometers.
*Small ~1-2 micrometers.


Images:
====Images====
*[http://commons.wikimedia.org/wiki/File:Leishmania_donovani_01.png Leishmania - smear (WC)].
<gallery>
*[http://commons.wikimedia.org/wiki/File:Leishmania_2009-04-14_smear.JPG Leishmania - bone marrow (WC)].
Image:Leishmania_donovani_01.png | Leishmania - smear. (WC)
Image:Leishmania_2009-04-14_smear.JPG | Leishmania - bone marrow. (WC)
Image:Cutaneous_Leishmaniasis_x100 | Leishmania - cutaneous. (WC)
</gallery>
www:
*[http://www.cdc.gov/parasites/leishmaniasis/index.html Leishmania and sand fly (cdc.gov)].
*[http://www.cdc.gov/parasites/leishmaniasis/index.html Leishmania and sand fly (cdc.gov)].


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{{Main|Bacteria}}
{{Main|Bacteria}}
This is a small topic when considered from the perspective of an anatomical pathologist.  Most stuff is sorted-out by microbiology.
This is a small topic when considered from the perspective of an anatomical pathologist.  Most stuff is sorted-out by microbiology.
=Protozoa=
A historical category of organisms. Lifeforms previously categorized as ''protozoa'' are in several different ''kingdoms''.
{{Main|Amebiasis}}
{{Main|Leishmaniasis}}
{{Main|Pneumocystis jirovecii}}
{{Main|Toxoplasma}}


=Microorganisms and cancer=
=Microorganisms and cancer=
==Bacteria and cancer==
*[[Helicobacter pylori]] - [[MALT lymphoma]], [[gastric carcinoma]].
==Parasites==
*[[Schistosoma haematobium]] - [[squamous cell carcinoma of the urinary bladder]].
*[[Clonorchis sinensis]]
==Viruses and cancer==
==Viruses and cancer==
A number of microorganisms are associated with the development of cancer:<ref>{{Ref PCPBoD8|168}}</ref>
A number of microorganisms are associated with the development of cancer:<ref>{{Ref PCPBoD8|168}}</ref>
Line 350: Line 392:
*[[Hepatitis C]] - [[HCC]].
*[[Hepatitis C]] - [[HCC]].
*[[Lymphoma#Adult_T-cell_leukemia.2Flymphoma|Human T-cell lymphotropic virus type I]] (HTLV-1) - [[Adult T-cell leukemia/lymphoma]].
*[[Lymphoma#Adult_T-cell_leukemia.2Flymphoma|Human T-cell lymphotropic virus type I]] (HTLV-1) - [[Adult T-cell leukemia/lymphoma]].
*[[Human herpesvirus-8]] (HHV-8) - [[Kaposi sarcoma]], primary effusion lymphoma, body cavity lymphoma.  
*[[Human herpesvirus-8]] (HHV-8) - [[Kaposi sarcoma]], [[primary effusion lymphoma]], body cavity lymphoma.  
*[[Merkel cell carcinoma|Merkel cell polyomavirus]] - [[Merkel cell carcinoma]].
*[[Merkel cell carcinoma|Merkel cell polyomavirus]] - [[Merkel cell carcinoma]].
==Bacteria and cancer==
*[[Helicobacter pylori]] - [[MALT lymphoma]], [[gastric carcinoma]].
==Parasites and cancer==
*[[Schistosoma haematobium]] - [[squamous cell carcinoma of the urinary bladder]].
*Clonorchis sinensis (AKA Opisthorchis sinensis) - [[cholangiocarcinoma]].
*Opisthorchis viverrini - [[cholangiocarcinoma]].


=See also=
=See also=
Line 361: Line 411:
{{reflist|2}}
{{reflist|2}}


=External links=
*[http://www.fujita-hu.ac.jp/~tsutsumi/index.html Pathology of Infectious Diseases (fujita-hu.ac.jp)].


[[Category:Basics]]
[[Category:Basics]]
[[Category:Microorganisms]]
[[Category:Microorganisms]]

Latest revision as of 15:43, 4 December 2023

Microorganisms show-up every once in a while. It is essential to know 'em.

Microorganisms

Fungi

Name (disease) Kingdom Size Shape Stains Other (microscopic) Clinical References Image
Aspergillus (aspergillosis) Fungi ? Hyphae that branching
with 45 degrees angle 		PAS-D Fruiting heads when aerobic ? Immunosuppression [1]
Aspergillus. (WC)
Zygomycota (zygomycosis);
more specific
Mucorales (mucormycosis) 		Fungi ? Branching hyphae with variable width ? Granulomata assoc. Diabetes, immunodeficient [1]
Zygomycosis. (WC)
Coccidioides, usually C. immitis
(coccidioidomycosis) 		Fungi Large - 20-60 micrometers,
endospores 1-5 micrometers 		Spherules Stains? Other? Immunodeficient [1] Coccidioidomycosis (med.sc.edu)
C. immitis (WC)
Histoplasma (histoplasmosis) Fungi 2-5 micrometers Spherical GMS Intracellular (unlike candida), granulomata Source: soil with bird droppings [1]
Histoplasmosis. (WC)
Blastomyces (blastomycosis) Fungi 5-15 micrometres Spherical (yeast) Stains? Granulomas, broad-based budding yeast Habitat: Northeast America, Africa [1][2]
Blastomyces. (WC)
Paracoccidioides (paracoccidioidomycosis) Fungi 6-60 micrometres Spherical (yeast) Stains? Multiple budding "steering wheel" appearance Clinical??? [1]
P. brasiliensis (WC)
Pneumocystis jirovecii (pneumocystis carinii pneumonia; abbrev. PCP) Fungi (previously thought to be a protozoan) 7-8 micrometres "Dented ping-pong ball" GMS Usually in clusters of alveolar casts with a honeycomb appearance HIV/AIDS associated [3]
PCP. (WC)
Cryptococcus (cryptococcosis) Fungi 5-15 micrometres Yeast GMS Prominent (i.e. thick polysaccharide) capsule HIV/AIDS associated, most common CNS fungus [1]
Crytococcosis - mucicarmine (WC)

Notes:

  • Bold text = key features.

Fungi

Main article: Fungi
  • There are lots of 'em. Below are a few of 'em.

Terminology:[4]

  • Hyphae = microscopic filamentous growth (of fungi) -- single cell.
  • Mycelial = filamentous network of hyphae.
  • Septae/septation = hyphae may be subdivided by septae -- if they aren't they are one mass of protoplasm. (?)
  • Dimorphism = exist in two forms; e.g. single cell (yeast) and mycelial growth.
  • Pseudohyphae = looks like hyphae --but branching pattern is created by separate cells.[5]

Tissue invasive fungi

Typically:[6]

  • Mucor.
  • Aspergillus.

List

Worms & stuff

Schistosomiasis

See Urine cytopathology.

General

  • Trematode, i.e. type of worm.

Microscopic

Features of ova (S. haematobium):[7]

  • Elliptical ~140 micrometres max dimension.
  • "Spike" approx. the size of a PMN.

Images

  • Schistosomiasis haematobia. (WC)

  • Schistosoma japonicum. (WC/KGH)

  • Schistosoma japonicum. (WC/KGH)

  • Schistosoma japonicum. (WC/KGH)

  • Schistosoma eggs - intermed. mag. (WC/Nephron)

  • Schistosoma eggs - very high mag. (WC/Nephron)

www:

Toxoplasma

General

  • Common CNS infection.
    • Toxoplasma gondii - pathogenic; causes toxoplasmosis.
  • Previously classified as a protozoa.
  • A TORCH infection.

Microscopic

General:

  • Tachyzoites (Invasive form):
    • Crescent-shaped organisms that are 2-3μm wide by 4-8μm long.
  • Bradyzoites:
    • Are founded within the tissue cysts and are shorter than tachyzoites.
  • Oocysst:
    • Ovoid shape that measures 10μm to 12μm and contains four sporozoites.
  • Histopathological features depend on location in body.

Lymph node

LN features:[8]

  • Reactive germinal centers (pale areas - larger than usual).
    • Often poorly demarcated - due to loose epithelioid cell clusters at germinal center edge - key feature.
  • Epithelioid cells - perifollicular & intrafollicular.
    • Loose aggregates of histiocytes (do not form round granulomas):
      • Abundant pale cytoplasm.
      • Nucleoli.
  • Monocytoid cells (monocyte-like cells) - in cortex & paracortex.
    • Large cells in islands/sheets key feature with:
      • Abundant pale cytoplasm - important.
      • Well-defined cell border - important.
      • Singular nucleus.
    • Cell clusters usually have interspersed neutrophils.

Images (lymph node):

CNS

CNS features:[9]

  • Granular appearing ball ~ 2x the size of resting lymphocyte.
Images (CNS)

  • CNS toxoplasmosis - very high mag. (WC)

  • CNS toxoplasmosis - IHC - very high mag. (WC)

www:

Heart

Features:

  • Intramuscular organisms.

DDx:

Images (heart):

IHC

  • IHC for toxoplasma.[10]

Strongyloidiasis

General

  • Causes by worm Strongyloides stercoralis.
  • High case mortality rate ~ 70%.[11]
  • May present after years of latency due to immune suppression.[12]

Location:

  • Lung. (???)

Microscopic

Features:

  • Long worms.
  • ~10-15 micrometers wide.

Images

  • Strongyloides. (WC)

www:

Echinococcus

Microscopic

Features:

  • Laminated wall +/- calcification.[13]
  • Organisms:
    • Hooklets.
    • Scoleces - knoblike anterior end of a tapeworm.[14]

Enterobius vermicularis

  • AKA pinworm.

General

Gross

  • Peri-anal white squiggly thing ~ 2-13 mm in length.

Image:

Microscopic

Features - organism:

  • 0.2-0.5 mm width x 2-13 mm length.
  • Characteristic triangular "spikes" seen on cross section - base x height ~ 30 x 30 μm.
    • Spikes is in quotations, as these are really a longitudinal blade-like ridges, that run the length of the worm.

Features - eggs:[16]

  • Ovoid - double walled shells, one side flat.

Images

www:

  • Enterobius - very low mag. (WC)

  • Enterobius - high mag. (WC)

  • Pinworm (WC)

Trichinella

General

  • Causes Trichinosis.
    • Classically associated with uncooked pork.[17]
  • Several types; most due to T. spiralis.[17]

Microscopic

Features:

  • Worm.

Image:

Cysticercosis

General

  • Caused by Taenia solium; pork tapeworm.
  • May cause epilepsy; most common parasitic CNS infection.[19]

Gross

  • Multiple cystic spaces.

Image:

Microscopic

Features:

  • Large ovoid body with complex structures (cross-section of worm) - size: millimetres.
    • +/-External eosinophilic microvilli.
    • +/-Gastrointestinal tract - ovoid structure within the worm.

Notes:

  • Histomorphology is not distinctive for the type... microbiology usually figures it out.

Images:

Rhinosporidiosis

Not to be confused with rhinoscleroma.

General

  • Caused by parasite Rinosporidium seeberi.
    • India, Sri Lanka.
  • Nasal mass.
    • May present with obstruction.[20]

Microscopic

Features:[21][20]

  • Globular cysts ~ 100 micrometers with endospores:
    • Hyperchromatic (blue) spherical 10-100 micrometer.

Images:

Stains

Leishmaniasis

General

  • Caused by protozoa in the group Leishmania group.
  • Transmitted to humans by the sand fly.

May be:

Microscopic

Features:

  • Small ~1-2 micrometers.

Images

  • Leishmania - smear. (WC)

  • Leishmania - bone marrow. (WC)

  • Cutaneous Leishmaniasis x100

    Leishmania - cutaneous. (WC)

www:

Stains

Viruses

Main article: Viruses

This is a fairly big topic. There are about half a dozen viral inclusions (e.g. CMV, HSV, VZV, adenovirus) a decent pathologist ought to be able to identify. The virus article covers 'em.

Bacteria

Main article: Bacteria

This is a small topic when considered from the perspective of an anatomical pathologist. Most stuff is sorted-out by microbiology.

Protozoa

A historical category of organisms. Lifeforms previously categorized as protozoa are in several different kingdoms.

Main article: Amebiasis
Main article: Leishmaniasis
Main article: Pneumocystis jirovecii
Main article: Toxoplasma

Microorganisms and cancer

Viruses and cancer

A number of microorganisms are associated with the development of cancer:[25]

Bacteria and cancer

Parasites and cancer

See also

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Lefkowitch, Jay H. (2006). Anatomic Pathology Board Review (1st ed.). Saunders. pp. 682. ISBN 978-1416025887.
  2. ↑ http://pathmicro.med.sc.edu/mycology/mycology-6.htm
  3. ↑ Lefkowitch, Jay H. (2006). Anatomic Pathology Board Review (1st ed.). Saunders. pp. 684. ISBN 978-1416025887.
  4. ↑ http://www.fungionline.org.uk/1intro/3growth_forms.html
  5. ↑ http://pathmicro.med.sc.edu/mycology/mycology-3.htm
  6. ↑ CM 17 Apr 2009.
  7. ↑ URL: http://path.upmc.edu/cases/case622/dx.html. Accessed on: 26 January 2012.
  8. ↑ Ioachim, Harry L; Medeiros, L. Jeffrey (2008). Ioachim's Lymph Node Pathology (4th ed.). Lippincott Williams & Wilkins. pp. 113. ISBN 978-0781775960.
  9. ↑ URL: http://moon.ouhsc.edu/kfung/jty1/opaq/PathQuiz/N0I001-PQ01-M.htm. Accessed on: 19 October 2010.
  10. ↑ URL: http://moon.ouhsc.edu/kfung/jty1/opaq/PathQuiz/N0I001-PQ01-M.htm. Accessed on: 19 October 2010.
  11. ↑ Lim, S.; Katz, K.; Krajden, S.; Fuksa, M.; Keystone, JS.; Kain, KC. (Aug 2004). "Complicated and fatal Strongyloides infection in Canadians: risk factors, diagnosis and management.". CMAJ 171 (5): 479-84. doi:10.1503/cmaj.1031698. PMID 15337730.
  12. ↑ Siddiqui, AA.; Berk, SL. (Oct 2001). "Diagnosis of Strongyloides stercoralis infection.". Clin Infect Dis 33 (7): 1040-7. doi:10.1086/322707. PMID 11528578.
  13. ↑ Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 448. ISBN 978-1416054542.
  14. ↑ http://www.thefreedictionary.com/scoleces. Accessed on: 10 January 2010.
  15. ↑ Dahlstrom, JE.; Macarthur, EB. (Oct 1994). "Enterobius vermicularis: a possible cause of symptoms resembling appendicitis.". Aust N Z J Surg 64 (10): 692-4. PMID 7945067.
  16. ↑ Lefkowitch, Jay H. (2006). Anatomic Pathology Board Review (1st ed.). Saunders. pp. 685. ISBN 978-1416025887.
  17. ↑ 17.0 17.1 Kaewpitoon N, Kaewpitoon SJ, Philasri C, et al. (October 2006). "Trichinosis: epidemiology in Thailand". World J. Gastroenterol. 12 (40): 6440–5. PMID 17072975. http://www.wjgnet.com/1007-9327/12/6440.asp.
  18. ↑ URL: http://library.med.utah.edu/WebPath/EXAM/IMGQUIZ/msfrm.html. Accessed on: 5 December 2010.
  19. ↑ Prasad KN, Prasad A, Verma A, Singh AK (November 2008). "Human cysticercosis and Indian scenario: a review". J. Biosci. 33 (4): 571–82. PMID 19208982.
  20. ↑ 20.0 20.1 20.2 Morelli, L.; Polce, M.; Piscioli, F.; Del Nonno, F.; Covello, R.; Brenna, A.; Cione, A.; Licci, S. (2006). "Human nasal rhinosporidiosis: an Italian case report.". Diagn Pathol 1: 25. doi:10.1186/1746-1596-1-25. PMC 1560165. PMID 16945122. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1560165/.
  21. ↑ URL: http://www.histopathology-india.net/Rhino.htm. Accessed on: 4 January 2012.
  22. ↑ URL: http://www.arquivosdeorl.org.br/conteudo/acervo_eng.asp?id=428. 4 January 2012.
  23. ↑ 23.0 23.1 Goto, H.; Lindoso, JA. (Apr 2010). "Current diagnosis and treatment of cutaneous and mucocutaneous leishmaniasis.". Expert Rev Anti Infect Ther 8 (4): 419-33. doi:10.1586/eri.10.19. PMID 20377337.
  24. ↑ den Boer, ML.; Alvar, J.; Davidson, RN.; Ritmeijer, K.; Balasegaram, M. (Sep 2009). "Developments in the treatment of visceral leishmaniasis.". Expert Opin Emerg Drugs 14 (3): 395-410. doi:10.1517/14728210903153862. PMID 19708817.
  25. ↑ Mitchell, Richard; Kumar, Vinay; Fausto, Nelson; Abbas, Abul K.; Aster, Jon (2011). Pocket Companion to Robbins & Cotran Pathologic Basis of Disease (8th ed.). Elsevier Saunders. pp. 168. ISBN 978-1416054542.

External links

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