malaria screening in remote mission lab

[kackieanne]

I have a colleague who is doing laboratory work as part of a medical mission in Central America.

The only hematology stain she has is a quick stain with three bottles;  fixative, stain A (pink, presumably eosin) and Stain B (blue, presumably methylene blue)

She is asking about using the stain in malaria testing.

I know the CDC recommends Giemsa, and using Wrights only as a quick test for follow up with Giemsa.  Neither is an option for her.

Does anyone on the listserve have any experience with detecting malaria on a quick stained blood smear?

 

Edited February 17, 2020 by kackieanne

[daviem]

We use fields stain for thick film staining with no issues. I have used it also for thin films in similar circumstances as your colleague and due to the number of positive cases and % positive had no problems or issues. 

[Zagami]

Dear kackieanne,

The coloring system you mentioned and used in Central America is called Diff-Quick and is a quick variant of the Romanosky coloring. This is an excellent stain for peripheral blood smears, but less sensitive for staining of malarial plasmodium. On the other hand, Field's coloring, as told by davierm, is more valid, of which I'm sending you the specifications for local production, which I proposed in my mission in Kinshasa (DRC) the Malaria Field Stain: Eosin stain: dissolve 1.3 g eosin Y by active stirring in 500 ml dH2O containing 12.6 g Na2HPO4.12H2O and 6.25 g KH2PO4 (Sorensen’s buffer at pH 6.8). Stand it at room temperature for 24 hours in a closed container; Polychrome methylene blue: dissolve 1.3 g methylene blue (C.I. 52015) in 500 ml dH2O containing 12.6 g of Na2HPO4.12H2O and boiled to dry powder to polychrome the dye is obtained. Dissolve the powder in 500 ml of dH2O containing 6.25 g KH2PO4.