Tissues Flashcards
Selection of tissues with protozoal & helminth infections
Brain
Trypanosoma brucei
(Blood protozoa/ Hemoflagellate)
Brucei in Brain
See Morula cells (modified antibody producing B cells, larger than other lymphocytes) - look like mauve berries with clear surround (A)
See perivascular cuffing (B) in otherwise normal brain tissue (no inflammation or haemorrhages)
Lymph gland aspirates can be examined to diagnose African Trypanosomiasis
Brain
P.falciparum schizonts sequestrated in the capillaries, where phagocytic cells have engulfed the released black malaria pigment (haemozoin).
The surrounding brain tissue is normal
Muscle
Trypanosoma cruzi
100’s of Amastigotes contained in Pseudocysts (faint ball of reddish/purple dots in Cardiac smooth muscle)
Chagas Disease
Vector: Triatomine bugs (Panstrongylus) transmits Trypanosoma Cruzi (Haemoflaggelate/Blood protozoa)
Tx: benznidazole or nifurtimox
Cardiac smooth muscle as nuclei are in centre of muscle cells
Muscle
Trypanosoma cruzi
100’s of Amastigotes contained in Pseudocysts (faint ball of reddish/purple dots in Cardiac smooth muscle)
Chagas Disease
Vector: Triatomine bugs (Panstrongylus) transmits Trypanosoma Cruzi (Haemoflaggelate/Blood protozoa)
Tx: benznidazole or nifurtimox
Cardiac smooth muscle as nuclei are in centre of muscle cells
Muscle
Taenia solium
See large cysticercus or bladder worm (larvae) with inverted scoleces with crown of hooks in horseshoe (looks like celery slice) surrounded by suckers
Seen at x4
Pork Tapeworm
Cysticercosis from ingestion of ova
Skeletal smooth muscle as nuclei are at the side of muscle cells
Lymph
Filarial Nematodes
Either Wucheria bancrofti or Brugia sp. - cannot speciate in tissues
Thick cuticle surrounding adult worm with double-uterus in cross-section. The adults are in the ducts so appear to be sitting in a space.
See eggs differentiating into early larvae (microfilariae) in the double uteri.
Lymphatic Filariasis
Vector: Culicine mosquitoes
Tx. : DEC (diethylcarbamazine) +/- Doxy
Lymph node tissue ducts
Lymph
Adult Filarial Nematodes
Either Wucheria bancrofti or Brugia sp. - cannot speciate in tissues
Thick cuticle surrounding adult worm with double-uterus in cross-section. The adults are in the ducts so appear to be sitting in a space.
See eggs differentiating into early larvae (microfilariae) in the double uteri.
Lymphatic Filariasis
Vector: Culicine mosquitoes
Tx. : DEC (diethylcarbamazine) +/- Doxy
Lymph node tissue ducts
Skin
Onchocerca volvulus
A = Adult filarial nematode embedded in tissue
B = classic double uterus containing eggs & Mf.
C = microfilariae inside double uterus
D = microfilariae in surrounding tissue
Subcutaneous Filariasis, Onchocerciasis (River Blindness)
Vector: Simulium Black fly/’Buffalo fly’
Tx. Ivermectin +/- Doxy. NOT DEC
(Caution if Loa)
Skin nodule (surrounded by fibrotic capsule)
Muscle
Trichinella spiralis
Encrusted Spiralled larvae in striated & skeletal muscle, surrounded by cellular infiltrates.
Juvenile: 75-120µm
Fully developed: 1mm
Skeletal smooth muscle as nuclei are at the side of muscle cells
Muscle
Trichinella spiralis
Encrusted Spiralled larvae in striated & skeletal muscle, surrounded by cellular infiltrates.
Juvenile: 75-120µm
Fully developed: 1mm
Skeletal smooth muscle as nuclei are at the side of muscle cells
Brain
P.falciparum schizonts sequestrated in the capillaries, which is now blocked, with haemorrhages in the surrounding brain tissue.
Causing Cerebral Malaria
Liver
P.falciparum schizonts containing malaria pigment (haemozoin), sequestrated in the Kupffer cells (Hepatic phagocytic cells) within the sinusoidal spaces between hepatocytes.
Liver
Leishmania sp.
(Blood protozoa/ Hemoflagellate)
See purpleLeishmaniasis amastigotes (B) in macrophages/Kupffer cells (D) inbetween the hepatocytes (A)
Liver
Fasciola hepatica Adult
Large liver fluke (3cm) with multiple guts & rough tegument in the liver tissue
Fasciola migrates through the liver causing acute symptoms, eosinophilia & detectable antibody response. (Facilitate diagnosis before eggs are detectable in the faeces).
Liver
Fasciola hepatica Adult
Large liver fluke (3cm) with multiple guts & rough tegument in the billiary tree
Liver
Clonorchis sinensis Adult
Large liver fluke (2cm) with double gut & smooth tegument in the billiary tree
Liver
Fasciola hepatica Adult
Large liver fluke (3cm) with multiple guts & rough tegument in the billiary tree
Liver
Clonorchis sinensis Adult
Large liver fluke (2cm) with double gut & smooth tegument in the billiary tree
Liver
What are the features labelled?
Fasciola hepatica Adult in the billiary tree
A - multilobed gut
B - egg
C - rough spiney tegument
Large liver fluke (3cm)
Liver
What are the features labelled?
Clonorchis sinesis Adult in the billiary tree
A - double branched gut
B - smooth tegument
C - eggs
Large liver fluke (2cm)
Liver
Echinococcus multilocularis
Cysts are characterised by having multiple chambers of protoscolices (larvae) which are separated by thin walls.
Canid Tapeworm
Multilocular hydatid Disease or alveolar echinococcus from ingestion of ova - very invasive.
Liver
Echinococcus multilocularis
Cysts are characterised by having multiple chambers of protoscolices (larvae) which are separated by thin walls.
Canid Tapeworm
Multilocular hydatid Disease or alveolar echinococcus from ingestion of ova - very invasive.
Liver
Echinococcus granulosus
See single hydatid cyst characterised by having a single triple walled chamber containing daughter cysts, containing brood capsules containing protoscolices (larvae).
Canid Tapeworm
Unilocular hydatid Disease or cystic echinococcus from ingestion of ova.
Liver
What is this structure and what are the names of the 3 layers?
Hydatid cyst caused by ingestion of Echinococcus granulosus ova
See single hydatid cyst characterised by having a single triple walled chamber containing daughter cysts, containing brood capsules, containing protoscolices (larvae).
- Outer granular layer
- Middle laminated layer
- Inner germinal layer
Canid Tapeworm
Unilocular hydatid Disease or cystic echinococcus
Brain
P.falciparum schizonts containing black pigment (haemozoin), sequestrated in the capillaries, with ring haemorrhages.
Causing cerebral malaria
Brain
Reactivated Toxoplasma gondii
Tissue shows perivascular cuffing with surrounding haemorrhages and adjacent tissue necrosis
On closer inspection would see tachycysts consisting of loosely packed tachyzoites (active)
(~5x3µm)
Brain
Reactivated Toxoplasma gondii
Tissue shows perivascular cuffing with surrounding haemorrhages and adjacent tissue necrosis (pale pink)
Commonly seen in AIDS patients
On closer inspection would see tachycysts consisting of loosely packed tachyzoites (active)
(~5x3µm)
Brain
Dormant Toxoplasma gondii
Shows bradycyst - a discreet body which is tightly packed with the bradyzoites
No surrounding tissue inflammation, haemorrhage or necrosis
Brain
Dormant Toxoplasma gondii
Shows bradycyst - a discreet body which is tightly packed with the bradyzoites
No surrounding tissue inflammation, haemorrhage or necrosis
Brain
P.falciparum schizonts containing black pigment (haemozoin), sequestrated in multiple capillaries, with surrouding ring haemorrhages.
Seen in Cerebral malaria
Brain
P.falciparum schizonts containing black pigment (haemozoin), sequestrated in multiple capillaries, with ring haemorrhage surrounding transverse section of capilliary.
Seen in Cerebral malaria
Liver
P.falciparum schizonts containing malaria pigment (haemozoin), sequestrated in the Kupffer cells (Hepatic phagocytic cells) within the sinusoidal spaces between hepatocytes.
Bowel
Entamoeba histolytica
‘Flask shaped’ ulcer in mucosal surface caused by Entamoeba histolytica trophozoites invading healthy tissues at base of the ulcer
Large bowel with flattened villae
Bowel
Schistosomiasis sp.
Paired adults in copula in mesenteric veins (A) containing black pigment of ingested RBCs.
See eggs (C) in the surrouding tissues surrounded by granulomas (B)
(Shisto Shnuggles)
Large bowel with flattened villae
Bowel
Enterobius vermicularis adult worm
See adult worm free-floating in gut lumen with characteristic lateral alae along entire length of body. Usually found in appendix.
May also see double-bulbed oesophagus & eggs in lumen.
Thread or pin worm (Intestinal Nematode)
Perianal puritis - can be collected with “Scotch-tape to skin”
Large bowel with flattened villae
Liver
Schistosomiasis japonicum or mansonai
See eggs (A) surrounded by granulomas (discrete reaction of surrounding eosinophils/neutrophils) and pale pink fibrosis (C) within hepatocytes.
Trematode/Blood fluke
Bowel
Strongyloides
See ALL STAGES:
Free-living adults in cross-section - dark purple bubble with multiple compartments & double bulbed oesophagus, embedded in mucosa
Larvae - small, curved with uniform appearance (look like slender tubes with dots)
Eggs - look like hookworm but smaller with yellowish refractile wall
Small bowel with multiple villae and deep crypts
Bowel
Strongyloides
See ALL STAGES:
Free-living adults in cross-section - dark purple bubble with multiple compartments & double bulbed oesophagus, embedded in mucosa
Larvae - small, curved with uniform appearance (look like slender tubes with dots)
Eggs - look like hookworm but smaller with yellowish refractile wall
Small bowel with multiple villae and deep crypts
Bowel
Strongyloides
See ALL STAGES:
Free-living adults in cross-section - dark purple bubble with multiple compartments & double bulbed oesophagus, embedded in mucosa
Larvae - small, curved with uniform appearance (look like slender tubes with dots)
Eggs - look like hookworm but smaller with yellowish refractile wall
Small bowel with multiple villae and deep crypts
Bowel
Entamoeba histolytica trophozoite (foamy pink bodies with single nuclei - middle arrow)
Seen in healthy tissue adjecent to necrotic tissue at base of ‘Flask shaped’ ulcer in mucosal surface
This is zoomed in but would indentifiy as Large bowel due to flattened v
Bowel
Entamoeba histolytica trophozoite
Foamy pink bodies with single nuclei surrounded by clear space
Seen in healthy tissue adjacent to necrotic tissue at base of ‘Flask shaped’ ulcer in mucosal surface
Zoomed in but would indentifiy as Large bowel due to flattened villae
Bowel
Entamoeba histolytica trophozoite (foamy pink bodies with single nuclei - arrows)
Seen in healthy tissue adjecent to necrotic tissue at base of ‘Flask shaped’ ulcer in mucosal surface
Large bowel due to flattened villae
Lung
Pneumocystis jirovecii in a lung section
Silver in stain binds to the pneumocysts staining them black, encased in foamy exudate within the alveolus
Grocott stained section of lung with pale green/teal lung tissue
Lung
Pneumocystis jirovecii in a lung section
Silver in stain binds to the pneumocysts staining them black, encased in pale foamy exudate within the alveolus
Grocott stained section of lung with pale green/teal lung tissue
Bowel
Schistosomiasis sp.
Paired adults in copula in mesenteric veins (A) containing black pigment of ingested RBCs.
See eggs (C) in the surrouding tissues surrounded by granulomas (B)
(Shisto Shnuggles)
Large bowel with flattened villae
Spleen
Leishmania donovani amastigotes in Phagocytic cells
Haemoflaggelate
Visceral Leishmaniasis or Kala-azar – usually Indian subcontinent, East Africa and South America (see massive splenomegaly)
Vector: Female Sandfly
Phlebotomus genus Old World
Lutozmyia genus New World
Tx: Liposomal amphotericin B
