Hi Teresa, Very interesting. Do you have any references on mature and immature fungal cell walls and how they react histochemically?
Regards Tony Henwood MSc, BAppSc, GradDipSysAnalys, CT(ASC), FFSc(RCPA) Laboratory Manager & Senior Scientist, the Children’s Hospital at Westmead Adjunct Fellow, School of Medicine, University of Western Sydney Tel: 612 9845 3306 Fax: 612 9845 3318 Pathology Department the children's hospital at westmead Cnr Hawkesbury Road and Hainsworth Street, Westmead Locked Bag 4001, Westmead NSW 2145, AUSTRALIA ________________________________________ From: Goins, Tresa [[email protected]] Sent: Saturday, 2 May 2015 3:28 AM To: Paula Lucas; [email protected] Subject: Re: [Histonet] GMS Question To get a positive PAS or GMS fungal stain, one must oxidize the carbohydrate in the fungal cell wall. Chromic acid is a stronger oxidizer than periodic acid, so would work better with mature fungal cell walls that are highly polymerized. Treat an immature cell wall for too long, and you may get a false negative because the carbohydrate structure no longer resembles a fungal cell wall. Tresa -----Original Message----- From: Paula Lucas [mailto:[email protected]] Sent: Friday, May 01, 2015 8:17 AM To: [email protected] Subject: [Histonet] GMS Question Hello, I think I already know the answer but I'm not sure why so if someone can help me understand the theory behind it, I would greatly appreciate it. Currently, we use the Richard Allen kit for the GMS stain and it uses Periodic Acid as the 1st step. We use a control tissue from a case we had that was positive for fungus and it's a fungus ball from the Rt Maxillary. We ran a test for fungus on a different and current case of the same tissue (different patient): Rt Maxillary sinus. The control tissue did work, but the patient's tissue did not, so the doctor ordered a PAS for fungus and this clearly showed the fungal elements nicely. My question is why would the control and patient tissue have different results when they are both fungus balls from the same specimen source? Thanks in advance, Paula Lab Manager Bio-Path Medical Group _______________________________________________ Histonet mailing list [email protected] http://lists.utsouthwestern.edu/mailman/listinfo/histonet _______________________________________________ Histonet mailing list [email protected] http://lists.utsouthwestern.edu/mailman/listinfo/histonet ********************************************************************************* This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. If you are not the intended recipient, please delete it and notify the sender. Views expressed in this message and any attachments are those of the individual sender, and are not necessarily the views of The Sydney Children's Hospitals Network. This note also confirms that this email message has been virus scanned and although no computer viruses were detected, The Sydney Childrens Hospital's Network accepts no liability for any consequential damage resulting from email containing computer viruses. ********************************************************************************* _______________________________________________ Histonet mailing list [email protected] http://lists.utsouthwestern.edu/mailman/listinfo/histonet
