Diphtheria in the immunized with observations on a diphtheria-like disease associated with nontoxigenic strains of Corynebacterium diphtheriae

A series of thirty-five patients suffering from diphtheria, who had been previously fully inoculated against the disease and from whom toxigenic diphtheria bacilli were isolated, were investigated and compared with seventeen patients who had not been inoculated. There were smaller groups of those patients who had had incomplete courses of immunization and of those who had had previous attacks of the disease.

Two-thirds of the infections in the inoculated were due to Corynebacterium diphtheriae, intermedius type. Intermedius infections were proportionately more numerous in the inoculated than in the uninoculated, whereas gravis infections were less frequent.

Estimations of the antitoxin in the blood were made on admission. The inoculated patients had levels of antitoxin below, or in the neighbourhood of, that believed to confer protection.

In the inoculated group severity did not appear to be influenced by the level of antitoxin in the blood on admission.

Antitoxin in the blood was found to have increased after recovery from the disease in all except one patient; the increase was considerable in those who had been inoculated previously.

From 23·5% of all cases of clinical diphtheria investigated only non-toxigenic diphtheria bacilli (gravis, intermedius and mitis types) were isolated. These cases were considered separately. On admission the majority had in their blood considerable amounts of antitoxin, which did not increase after recovery. No other pathogenic organisms were regularly found. The possibility is discussed that under certain conditions non-toxigenic C. diphtheriae may be able to cause a diphtherialike disease.

TECHNICAL CONSIDERATIONS IN THE PREPARATION OF FLUORESCENT-ANTIBODY CONJUGATES

A comparison was made of (NH(4))(2)SO(4), HCl, ethodin, and ethanol for fractionation of rabbit antiserum prior to conjugation with fluorescein isothiocyanate. Fractionation with the salt was found to be the method of choice from the standpoints of simplicity and recovery of antibody effective in conjugates prepared from the fractions. Effects of pH, temperature, dye-protein ratio, and molarity and type of buffer upon conjugation were studied. These technical factors were adjusted to produce conjugates for Corynebacterium diphtheriae which possessed higher specific titers than did reagents obtained by previously employed techniques.

ANTIMICROBIAL ACTION OF NITROGEN-CONTAINING STEROIDS

Smith, Rodney F. (University of Maryland, Baltimore), Donald E. Shay, and Norman J. Doorenbos. Antimicrobial action of nitrogen-containing steroids. J. Bacteriol. 85:1295-1299. 1963.-A new group of 16 synthetic nitrogen-containing steroids have been tested against a variety of microorganisms for antimicrobial properties. The gradient plate screening method, serial dilution, and dry weight techniques were used in the studies. The organisms tested consisted of 14 gram-negative bacteria, 10 gram-positive bacteria, 2 actinomycetes, 7 yeasts, and 8 molds. Inhibitory properties were found to be specific and potent in four compounds, with inhibitory concentrations as low as 0.37 mug/ml. Three of the active steroids are 4-aza cholestanes and one is a 4-nor-3,5-secocholestane amide. Sensitivity to the compounds was greatest in the gram-positive bacteria, followed by the yeasts and molds. The gram-negative bacteria were not inhibited. All 16 steroids interfered to some extent with pigmentation in Serratia marcescens but not with pigment production in Pseudomonas aeruginosa. In a few instances, some of the molds were stimulated by the steroids at a concentration of 250 mug/ml.

IDENTIFICATION OF CORYNEBACTERIUM DIPHTHERIAE WITH FLUORESCENT ANTIBACTERIAL REAGENTS

Moody, Max D. (Communicable Disease Center, Atlanta, Ga.) and Wallis L. Jones. Identification of Corynebacterium diphtheriae with fluorescent antibacterial reagents. J. Bacteriol. 86:285-293. 1963.-Conditions are described whereby fluorescent-antibody reagents could be prepared and used to identify Corynebacterium diphtheriae in pure and mixed cultures and in clinical materials. The use of O and OK antigens for immunization of rabbits to prepare the antibody was compared. The most satisfactory reagents were those made from serum of rabbits injected with live (OK) suspensions of C. diphtheriae. Such fluorescent reagents were used successfully in direct and indirect fluorescent-antibody tests to identify both toxinogenic and atoxinogenic C. diphtheriae but not to differentiate the two kinds of organisms.

EFFECT OF HEMIN AND OXYGEN TENSION ON GROWTH AND NITRATE REDUCTION BY BACTERIA

Jacobs, N. J. (American Meat Institute Foundation, Chicago, Ill.), R. E. Heady, J. M. Jacobs, K. Chan, and R. H. Deibel. Effect of hemin and oxygen tension on growth and nitrate reduction by bacteria. J. Bacteriol. 87:1406-1411. 1964.-The effect of hemin supplementation of growth media on the ability of several bacteria to reduce nitrate was studied. Added hemin had no detectable effect on the ability of these organisms to reduce nitrate when grown in stationary cultures exposed to air. However, under anaerobic conditions, six strains of facultatively anaerobic staphylococci required hemin for nitrate reduction and growth stimulation in complex, nitrate-containing media. In a nutritionally defined medium, one strain of Staphylococcus required both hemin and nitrate for anaerobic growth. Anaerobic growth and nitrite production of the aerobe Bacillus subtilis was stimulated by addition of hemin. However, the anaerobic growth response was markedly de-decreased as compared with that obtained under static atmospheric conditions. Hemin had no detectable effect on anaerobic nitrate reduction or growth of the obligate aerobe Pseudomonas denitrificans, or of the facultative anaerobes Escherichia coli, B. polymyxa, and Corynebacterium diphtheriae.

SIALIDASE (NEURAMINIDASE) OF CORYNEBACTERIUM DIPHTHERIAE

Warren, Leonard (National Institute of Arthritis and Metabolic Diseases, Bethesda, Md.) and C. W. Spearing. Sialidase (neuraminidase) of Corynebacterium diphtheriae. J. Bacteriol. 86:950-955. 1963.-The characteristics of a sialidase produced by Corynebacterium diphtheriae were studied. The enzyme was partially purified from preparations of diphtheria toxin on a column of Sephadex G-75. By this means the lethal factor of diphtheria toxin was separated, in part, from the sialidase activity. There appeared to be a close immunological relationship between the sialidases of C. diphtheriae and clostridia, since a preparation of diphtheria antitoxin was as effective an inhibitor of diphtheria sialidase as of the sialidase of three species of clostridia. Conversely, antitoxin to clostridia inhibited diphtheria sialidase. Diphtheria antitoxin was essentially inactive toward influenza virus sialidase, and was completely inactive against purified sialidase of Vibrio cholerae. Removal of sialic acid from the proteins in a preparation of diphtheria antitoxin did not alter the inhibitory activity of the antitoxin against diphtheria sialidase. The enzyme operated optimally at pH 5.5 and did not require calcium ions for activity. The substrate specificity of diphtheria sialidase appears to be the same as that of other previously described sialidases.

IN VITRO AND IN VIVO LABORATORY EVALUATION OF CEPHALOGLYCIN AND CEPHALORIDINE

Two new antibiotics, structurally related to cephalothin, have been given the generic names cephaloglycin and cephaloridine. Cephaloglycin is the dipolar ion of 7-(d-alpha-aminophenylacetamido)-cephalosporanic acid. Cephaloridine is 7-[alpha-(2-thiophene)acetamido]-3-(1-pyridylmethyl)-3-cephem-4-carboxylic acid betaine. These new compounds were evaluated simultaneously. The broad spectrum of activity observed in vitro and in vivo with both antibiotics, the good oral absorption obtained with cephaloglycin, and the stability of cephaloridine are emphasized. The data suggest that both antibiotics merit clinical trial in humans.