Stephen J. Kraus

Factors Affecting the Performance of Smear and Culture Tests for the Detection of Neisseria gonorrhoeae

The probability of gonorrhea in men attending the DeKalb County, Georgia, clinic for sexually transmitted diseases with the chief complaint of urethral discharge and/or dysuria and whose urethral smears contain intracellular gram-negative diplococci is 94.8%. Absence of intracellular gram-negative diplococci from smears of the same men in associated with a 92.6% probability that they have nongonococcal urethritis rather than gonorrhea. There is a 97.3% probability of gonorrhea in our female patients at high risk of being infected and whose cervical smears contain intracellular gram-negative diplococci. Absence of intracellular gram-negative diplococci is associated with a probability of only 51.2% that these women do not have gonorrhea. The probability of gonorrhea in our male patients, whose smears contain intracellular gram-negative diplococci, drops from 94.8% to 34.9% when specimens are obtained from sexually active men without urethritis and to 53.9% when an inexperienced technician interprets smears from patients with urethritis. Vancomycin . HCl, which is included in Neisseria gonorrhoeae--selective media for suppression of microbial contaminants, also inhibited 2.4% of our gonococcal isolates and resulted in a falsely negative test. Awareness of these and other limitations of tests for gonorrhea, and of the magnitude and means of control of these limitations is essential to determining the presence or absence of gonococcal disease.

Isolation of Haemophilus species from the genital tract.

Haemophilus influenzae was isolated from the urethra of three of 85 men attending a sexually transmitted diseases clinic. These isolates of H. influenzae were nonencapsulated; one was biotype III, and two were biotype IV. Haemophilus parainfluenzae was isolated from the urethra or coronal sulcus of five men; three isolates were biotype II, and two were biotype III. Neither H. influenzae nor H. parainfluenzae was isolated from the genital secretions of 84 women. Haemophilus ducreyi and Haemophilus equigenitalis (contagious equine metritis bacterium) were not isolated from any of the 169 patients.

Complications of Gonococcal Infection

When the gonococci spread from the urethra and cervix they can cause serious medical problems. The introduction of sulphonamides and penicillin was accompanied by a marked reduction in the frequency of gonococcal complications. Since antibiotics the incidence of gonococcal arthritis has diminished to .1-.3% of cases. Gonorrheal arthritis formerly affected men more frequently but now it is more common in women. This change is attributed to the fact that males more often seek early treatment. Septicemic spread may cause generalized dermatitis arthritis endocarditis and meningitis. Although gonococci were thought to be restrained to local areas because they could survive only in tissues having columnar mucous epithelium recent immunologic mechanisms with serum bacteriological activity have been shown to be important also. Increased virulence of disseminated gonococci is another factor. Gonococci from systemic infectious behave differently from those of local infections and act more like meningococci. Menstruation and pregnancy appear to favor dissemination. Pelvic surgery also increases the risk. Septic gonococcal dermatitis occurs in 1-2% of patients with gonorrhea. The majority of cases are seen in female patients. Parenteral treatment with 4.5 million units of penicillin daily for 2 days followed by oral penicillin for 10 days has been successful. Some patients have a tendency to recover spontaneously . Gonococcal infection may extend from the cervix into the uterus and then into the fallopian tubes and finally into the peritoneal cavity. Abscess formation is the most frequent complication of acute pelvic inflammatory disease. Cul-de-sac aspirations usually reveal a mixed infection. Treatment therefore requires broad spectrum antibiotics. Tubal occlusion usually follows and causes infertility. Involvement of the heart is life-threatening. Arterial emboli can produce cerebral vas cular accidents or acute nephritis. Before the antibiotic era the gonoc occus was the etiology of 11-26% of cases of bacterial endocarditis. Since antibiotics in a report of a series of 95 cases of endocarditis no ne had gonococcal involvement and less that 5% of purulent pericarditis was of gonococcal origin. Reported incidence of abnormal electrocardiograms associated with disseminated gonorrhea has varied from 0 to 40%. Ophthalmic gonorrhea is a neonatal problem although adult cases do occur. Serious sequelae include corneal scarring perforation of the cornea panophthalmitis and phthisis bulbi. The antibiotic of choice is 50000 units/kg/day for children and 4.8 million units of procaine penicillin per day for adults. Local therapy is saline irrigation every 15 minutes followed by tetracline drops or chloramphenicol drops and decreasing in frequency as improvement occurs. Atropine drops are given concurrently. Treatment should be started early. The best prophylaxis is to treat the mothers in prenatal clinics and with 1% silver nitrate drops for the infant at birth. Gonococcal meningitis may occur in adults who have gential gonorrhea or in the newborn infant at birth.

Gonococcal urethritis diagnosed from enzyme immunoassay of urine sediment

First-catch urine specimens were obtained before clinical examination from 101 sexually active men who attended a sexually transmitted diseases clinic with a complaint of urethral discharge. Urethral swab specimens were used for preparation of smears and were then cultured on Martin-Lewis medium. Enzyme immunoassay (EIA) tests were performed on (1) uncentrifuged urine, (2) urine sediment, and (3) urine sediment diluted 1:6 with detergent buffer. Urethral cultures from 65 (64%) of the 101 men were positive for N. gonorrhoeae. EIA performed on urine sediment diluted 1:6 yielded the highest sensitivity: 98.5% (64/65). Sensitivity of EIA for uncentrifuged urine was only 66% (43/65). Specificity of all samples tested exceeded 97.2%. Overall agreement between results of EIA on diluted urine sediment and culture was 98% (99/101). Discordant culture and EIA results were unrelated to urine volume, time since prior urination, quantity of gonococcal growth on Martin-Lewis medium, duration of urine storage (less than 72 hours) before testing, or immunotype. EIA tests using urine sediment are highly sensitive and specific, and they offer an alternative means of diagnosing gonorrhea in men who refuse urethral manipulation. They also provide a means of screening men at high risk for gonorrhea who have submitted a urine specimen for other reasons.

A preliminary evaluation of the Gonozyme® test

Gonozyme® is a solid-phase enzyme immunoassay that detects antigens of Neisseria gonorrhoeae in clinical specimens. The test was 100% sensitive and 96.8% specific when applied to 71 urethral specimens from men with symptomatic urethritis, and 89.5% specific for 19 urethral specimens from men examined after eradication of gonorrhea by antibiotics. For cervical specimens obtained before therapy from 368 women with gonorrhea, the Gonozyme® test had a sensitivity of 88.5% and a specificity of 94.3%. The test was 100% specific when used for testing of 37 cervical specimens obtained after therapy of gonorrhea. The predictive values of a positive Gonozyme® test were 90.5% for cervical specimens from women attending sexually transmitted disease clinic and 97% for urethral specimens from men with urethritis. The predictive values of negative Gonozyme® tests in these same circumstances were 100% for urethral specimens and 93.6% for cervical specimens.

Cefoxitin vs. Penicillin in the Treatment of Uncomplicated Gonorrhea

Four hundred six men and women with gonorrhea were randomly assigned to receive either 2 g of cefoxitin or 4.8 X 10(6) units of aqueous procaine penicillin G intramuscularly. All patients also received 1 g of probenecid orally. There was no statistically significant difference in the failure rate between patients treated with penicillin (4.3%) and those treated with cefoxitin (5.1%). Twelve (92%) of 13 homosexual men with gonococcal proctitis who received penicillin and 19 (95%) of 20 who received cefoxitin were cured. Adverse reactions were infrequent and mild in the cefoxitin-treated group. Three patients who received penicillin developed reactions consistent with procaine toxicity. It is concluded that cefoxitin is a safe and effective alternative to penicillin for treating uncomplicated anogenital gonorrhea in men and women.

Therapy of uncomplicated gonorrhea due to antibiotic resistant Neisseria gonorrhoeae

Antibiotics available to treat uncomplicated anogenital infections due to beta-lactamase-producing Neisseria gonorrhoeae include spectinomycin, ceftriaxone, and clavulanic acid added to aqueous procaine penicillin G or amoxicillin. Important variables in deciding which antibiotic regimen to use include effectiveness against urethral, cervical, pharyngeal, and rectal infections; cost; eradication of coexisting incubating syphilis; adverse effects; efficacy against strains of N. gonorrhoeae with chromosomally mediated resistance to antimicrobial agents; ease of administration; patient acceptance; and the potential for inducing resistance to antimicrobial agents in pathogens other than those causing sexually transmitted diseases. This review outlines the advantages and disadvantages of the various regimens.

Treatment of uncomplicated gonococcal infection with trimethoprim-sulfamethoxazole.

The efficacy of trimethoprim-sulfamethoxazole (TMP-SMZ; 80 mg of TMP and 400 mg of SMZ per tablet; nine tablets taken once daily for three days; total, 27 tablets) was compared with the U.S. Public Health Service recommended regimen of 2 g of tetracycline daily for five days for the treatment of uncomplicated genital gonorrhea. Fourteen (3%) of the 461 patients treated with tetracycline and 24 (5%) of the 477 patients treated with TMP-SMZ failed to be cured; the difference between the two groups was not significant. Treatment of patients with TMP-SMZ was more likely to fail if the isolates of Neisseria gonorrhoeae had MICs of > or = 0.5 microgram of TMP/ml and > or = 9.5 micrograms of SMZ/ml. Adverse effects were more often reported by patients receiving TMP-SMZ. The results show that TMP-SMZ is an effective therapy for uncomplicated gonococcal infections in men and women and may also eliminate agents causing postgonococcal urethritis. The utility of this drug combination may be limited by the adverse effects that are associated with the large dose used.

Resources needed to culture Chlamydia trachomatis in laboratories of clinics for sexually transmitted diseases.

Genital infections with Chlamydia trachomatis may be more prevalent than infection with Neisseria gonorrhoeae and may have serious sequelae such as epididymitis and pelvic inflammatory disease in adults and conjunctivitis and pneumonia in neonates. A culture of the organism is the most sensitive and specific means for detecting C. trachomatis in the genital tract, yet this procedure is available only in specialized centers and universities. Establishment of a chlamydia laboratory as part of a clinic for sexually transmitted diseases (STD) requires major technical and financial resources. Technical resources include the expertise of technicians as well as specialized equipment, glassware, and reagents. The current (August, 1981) minimal cost of performing a chlamydial culture is estimated to be

Trichomonas vaginalis: Reevaluation of Its Clinical Presentation and Laboratory Diagnosis

14.69.