The Use of Penicillin and Streptomycin in the Routine Cultivation of Amebae from Fecal Specimens
Lois Norman AND
M. M. Brooke
Communicable Disease Center, Public Health Service, U. S. Department of Health, Education, and Welfare, Atlanta, Georgia
1. Four hundred and twelve fecal specimens from two surveyswere used to evaluate (a) the effect of adding antibiotics tothe culture medium employed in the diagnosis of intestinal amebaeand (b) cultivation as a diagnostic technique in comparisonwith other procedures performed on the same specimen. The cultivationroutine included the examination of permanently stained filmsprepared from culture sediments preserved in PVA-fixative. Thistype of examination facilitated the identification of organismsand increased the number of infections found.
2. The additionof small amounts of penicillin G sodium andstreptomycin sulfateto LER medium significantly increased thenumber of infectionsof intestinal amebae found in both old,normally passed specimens(Survey I) and fresh, post-catharticspecimens (Survey II).In general, the individual species reactedsimilarly to theaddition of the antibiotics.
3. As a diagnostic technique,cultivation was ineffective withold, normally-passed specimens,but superior to the other techniquesused (concentration andstained smears) when fresh, post-catharticspecimens were examined.These results indicate that cultivationwould not be a worthwhileroutine technique for laboratoriesthat usually receive mailedspecimens (for example, public healthlaboratories), but wouldbe advisable in clinics and hospitals.When fresh specimensare available, it is believed that a goodroutine consists ofa cultivation technique (including stainedpreparations) forthe identification of trophozoites and a concentrationtechniquefor the recovery of cysts.