Helen M. Keller

The relation of dysentery to the acute diarrheaof infants and children

Summary An intensive study on the stools of infants and children suffering fromacute diarrhea was carried out on 209 patients during the summer of 1938. From 102 patients (49 per cent) dysentery organisms were recovered. The seasonal incidence, case fatality rate and duration of gastroenteritis were not significantly different in the dysentery and nondysentery groups. The frequency distribution of the two groups according to the age of the patient was strikingly different. Seventy-five per cent of the patients under 1 year of age did not have dysentery while 75 per cent of those over 1 year did. The data have been analyzed statistically from the standpoint of the efficiency of several culture media used. Sodium desoxycholate citrate medium is markedly superior for isolating dysentery organisms. The type distribution of the dysentery organisms is given.

Sodium Sulfathiazole Resistant Shigella paradysenteriae Flexner and Sonne

Numerous reports have appeared regarding the development of sulfonamide resistance by pneumococci in vitro and in vivo, and by gonococci. We have not seen a similar report regarding Shigella paradysenteriae. In the course of our in vitro studies we have developed 2 sodium sulfathiazole resistant strains of Shigella paradysenteriae, one each of the Flexner and Sonne types. Sodium sulfathiazole was bactericidal for the parent Flexner strain in a concentration of 80 mg % and for the sulfonamide resistant sub-strain in a concentration of 600 mg %. Sodium sulfathiazole was bactericidal for the parent Sonne strain in a concentration of 300 mg % and for the sulfonamide resistant sub-strain in a concentration of 1000 mg %. The sulfonamide resistant Flexner strain retained its virulence for white mice (1 M.F.D. being 1.0 cc of 10-5 in 3% mucin), but was non-resistant to sodium sulfathiazole in vivo. The resistant Sonne strain became non-virulent. Further studies are planned with these parent and sulfonamide resistant strains and other sulfonamide compounds.

Sulfonamide Resistant Shigella paradysenteriae Flexner and Shigella sonnei

Summary Bacteriostatic and bactericidal concentrations of 6 sulfonamides in vitro after 2, 4 and 7 days for a resistant strain of Shigella paradysenteriae Flexner and 2 resistant strains of Shigella sonnei show that: The 3 resistant strains were not resistant to sulfapyrazine; the Sonnei (Ch) strain was in addition, not resistant to sulfacetamide; the Sonnei (Ma) strain was also not resistant to sulfacetamide according to the bactericidal concentrations, but as judged by the bacteriostatic concentrations was more resistant to sulfacetamide than was its parent strain; these 3 strains were quite resistant to the other sulfonamides.

Susceptibility of Shigella paradysenteriae tosodium sulfathiazole and sulfaguanidine in vitro

Summary Studies are reported on the bacteriostatic and bactericidal effectsof sodium sulfathiazole and sulfaguanidine in vitro on twelve strains of Shigella paradysenteriae Flexner, seven strains of Shigella paradysenteriae Sonne, and fifteen strains of a miscellaneous group of intestinal bacteria, most of them pathogenic. These studies differ from preceding studies in that the observations were made over a period of twenty-one days rather than one or two days, as is the usual custom, and each strain was studied in a series of at least nineteen different concentrations of the drugs instead of one, two, or three concentrations as is usual. Sulfaguanidine was bactericidal for only two of the thirty-four differentstrains tested, and these were both strains of Shigella paradysenteriae Flexner. Sodium sulfathiazole was bactericidal for all strains tested exceptone strain of Esch. coli which survived in media containing 2,000 mg. per cent of the drug. For the Flexner strains, sodium sulfathiazole was bactericidal for all in concentrations between 10 and 200 mg. per cent inclusive. For the Sonne strains, sodium sulfathiazole was bactericidal for all inconcentrations between 250 and 400 mg. per cent inclusive. For the miscellaneous group, sodium sulfathiazole was least bactericidal for strains of Esch. coli, E. typhosa, S. paratyphi , and two of the S. morgani . The bactericidal concentrations for these varied between 250 and more than 2,000 mg. per cent. For one strain of S. morgani , two of Shigella alkalescens , and two of Proteus, the bactericidal levels were between 60 and 120 mg. per cent, which are comparable to those observed for the Flexner cultures.