Waiting for the Cure

Eureka! I finally managed to see some hookworm larvae under the microscope. For a full visual description of the McMaster egg count, see: http://www.docstoc.com/docs/599020/Macmaster-counting-Technique-ppt

Results from 10 larvae? 800 epg

I’ll walk through my steps one by one. First, I bought the materials:

digital scale: myweigh ibalance 500 (more expensive then the cheaper models, but comes with a 30 year guarantee)

microscope: Wesco binocular, with lenses from 4X to 100X

measuring devices: one glass cylinder 50 ml., 1 plastic graduated flask, 500 ml, and 1 200 ml. glass beaker

cheesecloth, spoon, salt, water

pipettes

1 McMaster grid slide, bought from this site: http://www.vetslides.com/

First, I went to the bathroom in a plastic container. I weighed a piece of paper on my scale, then added 40 grams of salt. I then filled a plastic beaker with 100 ml. of water. Mixed well, until the salt dissolved. Then I measured a small plastic container and added 4 g. of stool to it. (If the plastic weighs 1.5 grams, for example, you would add stool until you get to 5.5 g.) I put the stool into a glass flask and added 56 ml. of the salt water mixture. I made sure to rinse the plastic cup with stool in the salt water, so as to capture all of the contents of the stool. Then I stirred the contents with a plastic knife until it was well mixed. I took the contents and strained it through a single layer of cheesecloth several times (it helps to have two glass open flasks for this.) Then I pipetted the mixture into both chambers of the McMaster slide and let it sit for 5 minutes. (Well, really 10 as I paused to have breakfast.)

I put the slide into the microscope at 10X 10 magnification. It takes a while to get used to the binocular lenses; I’m sure the technique improves with experience. The challenge I had is one focus allowed me to see the grid, the other focus I could see the eggs. A faint blurry line sometimes could be seen, but not always. I suggest shelling out extra for the green lined grid slide.

The eggs should look like this: (photo courtesy of www.flickr.com/photos/prep4md/2772121447/)

Because I couldn’t see the grid lines well, every time I identified an egg, I’d notice something around it, like little food blobs that had a particular shape or color to them, so I wouldn’t count an egg twice. I carefully went up and down each grid slide, and counted eggs. On the left side, I found 7 eggs, on the right, 9.

I added these up and multiplied by 50, resulting in 800 eggs per gram.

I should do multiple stool samples for accuracy. Right now my eyes hurt. I’m just happy I actually found and identified something.

So yes, 10 little hookworms result in 800 epg 4 months later. Happy egg counting!