Hello! Some days ago a sample from a patient possibly infected with schistosoma was sent to our laboratory for molecular analysis. The diagnostic was done by a rectal biopsy and staining with Ziehl-Neelsen. Some of my colleagues claim that only could be S. mansoni and S. intercalatum because only eggs from these spieces stain. However, in my opinion, eggs are not stained and it could be S. haematobium. Please, can anyone help with this question?
(I attach photographs of the rectal biopsy. The last 2 photography is the rectal biopsy of other patient with confirmed S. mansoni infection)
usually s. haematobium egg does not appear in rectal biopsy unless the infection is closed with sever fibrosis in chronic infection , it appears red calcified in h& E stain with terminal spine
It is difficult to tell for sure from your biopsy micrographs whether this is S. haematobium, S. intercalatum, or S. mansoni, since I cannot see a distinct spine to determine its position. It is more common to see S. haematobium in sections of the urinary bladder or prostate, or in other parts of the urinary and reproductive ducts. However, it is possible to see S. haematobium in rectal biopsies, though not as common as urogenital locations. Geographical information on the patient may also give some clues.
The patient came from Uganda. He took a bath in Victoria lake. When he was back he showed eosinophylia an those are the results of the rectal biopsy. We dom´t really kwon if it's S. mansoni or S. haematobium.
In the normal case in a rectal biopsy it could be S. mansoni not S. haematobium. But on the fotographs I don't see typical eggs of Schistosoma, not even eggs at all. There should be some eggs with spines and many immune cells around it. So I think it is something else, but at the moment I don't know what. I think it looks like tissue-cysts or something like that....
I found something in the internet. A slice of S. haematobium. It looks a lot like your first picture in my opinion. So it could be adults of S. mansoni I think, but normally you find eggs more than the adults, because they live in the blood vessels....
The appearance of S.haematobium ovum in tissue sections depends on what part of the ovum that was cut. It could be oval or oblique etc. There is usually a provocation of inflammatory response. Ziehl Neelsen stain is a useful special stain. The slide you sent looks like helminthic parasite am not sure if it an ovum or adult parasite. Can you take more sections including serial sections,it may show more details needed to identify what is in the slide.
As mentioned by Mahmoud Elsibaei, usually S. haematobium eggs does not appear in rectal biopsies, but it's not impossible. Although I have not much experience with histological preparations, I can tell that normally, with a Ziehl-Neelsen stain, S. haematobium is the only Schistosoma egg that is NOT acid-fast and thus will not stain red. All the other Schistosoma species eggs would stain acid-fast (red). Easiest would be to use the morphology off the egg, but as Unu Airauhi said, the spine, used in this case, is not always visible. Much will depend on where the egg has been cut.
I think you should repeat the Ziehl-Neelsen stain, there is too much background staining to determine presence or absence of stain on the organism. recheck your acid-alcohol strength or the length of time it takes to decolor non-acid fast material. Goodluck.
S. haematobium can be found in stool in 3-10% of cases (Cunin et al. Trop Med Int Health. 2003:1110-7), so it is possible to find them in rectal bx. I cannot tell from the section as mentioned, but a urine exam would go a long way to clarify this, since this appears to a recent infection and an embryonated egg.
- Badges
- Science topic
- Similar topics
- Medicine
- Disease
- Infectious Diseases