[Histonet] Re: HELICOBACTER CONTROLS

[RSRICHMOND <@t> aol.com]

Tasha R. Bourm at Olympic Medical Center in Port Angeles WA (up at the far 
end of the Olympic Peninsula - wotta view!) asks about Helicobacter pylori 
controls for staining gastric biopsy specimens, and several people replied.

The varied pathology services I've done locum tenens work for have real 
difficulty getting Helicobacter controls, mostly because the histotechnologists 
aren't communicating with the pathologists and the transcriptionists. When I see 
a case that would make a good Helicobacter control, I send in a special stain 
request form with "good Helicobacter control" scribbled on it instead of a 
request for a stain.

The ideal control tissue is a gastrectomy specimen crawling with bugs. 
Fortunately for patients, unfortunately for pathology services, such specimens have 
become rare. But look for these specimens; one good case can supply you with 
controls from now until your Social Security kicks in.

Helicobacter pylori is extremely difficult to culture - most small labs have 
never succeeded - so that cultures are an unlikely source of controls. I 
really don't like to see other bacteria used as controls.

Many services either don't do a Helicobacter control, or use some irrelevant 
piece of tissue - and all the commercial controls I've seen have been 
worthless. I don't think this is acceptable practice - though I don't think it's 
necessary to run a positive control with every Giemsa stain run (immune stains do 
of course require a positive control).

I've become convinced that it's necessary to use an oil immersion lens with 
Giemsa stains for Helicobacter, a view that makes me unpopular with my fellow 
pathologists. One of the advantages of the immune stain, in my personal 
experience, is that it allows you dispense with oil immersion, a time-consuming 
procedure.

Bob Richmond
Samurai Pathologist
Knoxville TN
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