Reactivity of microhemagglutination, fluorescent treponemal antibody absorption, and venereal disease research laboratory tests in primary syphilis.

Seroreactivity in 130 cases of primary syphilis was 91.5% by fluorescent treponemal antibody absorption test, 82.3% by microhemagglutination (MHA-TP test), and 68.5% by the Venereal Disease Reseach Laboratory (VDRL) test. The MHA TP test generally became reactive earlier than the VDRL test and confirmed all reactive and most weakly reactive VDRL results.

Comparison of serum and plasma specimens for syphilis serology using the reagin screen test.

One serum and three plasma samples were obtained from each of 125 normal individuals and from 140 patients with treated or untreated syphilis. Serum samples were tested by the Venereal Disease Research Laboratory (VDRL) test and by the Reagin Screen Test (RST). Plasma specimens were tested only with the RST. When tested within 24 h after collection, all specimens from normal individuals were nonreactive. Plasma specimens from normal individuals stored for up to 72 h after collection continued to yield a clearly nonreactive result in 423 of the 426 samples tested by the RST. Serum and plasma samples from syphilis patients tested within 72 h after collection by the RST yielded qualitative and quantitative results almost identical to results of serum tested by the VDRL test.

Rat bite fever misdiagnosed as Rocky Mountain spotted fever.

A patient who had been exposed to ticks and who had also been bitten by a laboratory rat developed fever, headache, and a rash. He was treated with chloramphenicol for Rocky Mountain spotted fever, and recovered. Blood cultures, however, grew Streptobacillus moniliformis, a causative agent of rat bite fever. The case report illustrates the clinical similarities between rat bite fever and Rocky Mountain spotted fever.

Feasibility of screening for penicillinase-producing Neisseria gonorrhoeae from primary culture plates by using a rapid microacidometric test.

We have shown that it is possible to screen for penicillinase-producing Neisseria gonorrhoeae directly from primary culture plates. Experiments involving the cocultivation of four genera of beta-lactamase-positive (beta-lac(+)) bacteria and a beta-lactamase-negative (beta-lac(-)) N. gonorrhoeae on modified Thayer-Martin medium indicated that suppressed or inhibited beta-lac(+) bacteria did not give false-positive results when isolated beta-lac(-) colonies of gonococci were tested. Colonies were assayed for beta-lac production by an adaptation of a microacidometric method in which bacteria could be tested before or after the addition of oxidase reagent.

Evaluation of reagin screen, a new serological test for syphilis.

A total of 1,020 serum and plasma specimens were tested using the Venereal Disease Research Laboratory (VDRL), Rapid Plasma Reagin (RPR) card, Reagin Screen (RST) and Fluorescent Treponemal Antibody-Absorption (FTA-ABS) tests. In 257 normal patients, all screening tests were nonreactive; the FTA-ABS test was reactive for one patient. In 588 patients with treated and untreated syphilis, the RST results were 91.7% in agreement with the VDRL and RPR results. In 175 patients with diseases that cause biological false reactions, the RST was 94% in agreement with the other screening tests. The titer of the RST was within one dilution of the corresponding VDRL titer in 91.7% of the 360 speciments tested and within one dilution of the RPR titer in 96.9% of 358 specimens quantitated by both tests.

Evaluation of the Gonosticon Dri Dot test in females with a low incidence of gonorrhea.

A group of 765 females attending a Planned Parenthood Clinic was screened for gonorrhea by inoculating Thayer-Martin plates and Transgrow bottles with specimens from the cervix. Blood was obtained at the same time and tested for anti-gonococcal antibody by using the Gonosticon Dri Dot test. In this low-incidence group, 18 positive cultures were detected by culture on Thayer-Martin plates, whereas Transgrow detected only 15 positive cultures. Of the 18 patients with gonorrhea, 11 exhibited reactive serum (agglutination of the latex particles). In the total population, 64% of the patients had nonreactive serum (no agglutination) and negative cultures; 25% had reactive serum and negative cultures. When this latter group was subdivided on the basis of race, blacks and Latin Americans were found to have a higher incidence of reactive serum with a corresponding negative culture than was found in whites. Patients who were originally culture positive and nonreactive in the Gonosticon Test were retested; three out of four patients retested within 6 to 11 days after the initial screening had converted to a positive Gonosticon test.