Confirmatory testing of Chlamydia trachomatis Syva enzyme immunoassay gray zone specimens by Syva direct fluorescent antibody test.

A series of gray zone specimens with sample to cutoff ratio of 0.7 to 0.99 encountered in routine use of the Syva Microtrak (Syva, Inc.) Chlamydia trachomatis enzyme immunoassay (EIA) test for urogenital specimens were subjected to repeat testing in duplicate and high-speed centrifugation with direct fluorescent antibody testing of the centrifugate. Immunofluorescent C. trachomatis elementary bodies were observed in high-speed centrifugates in more than 40% of two series of gray zone specimens examined indicating that a C. trachomatis gray zone result would require confirmatory testing.

Chloramphenicol and penicillin resistance in pneumococci isolated from blood and cerebrospinal fluid: a prevalence study in metropolitan Denver.

From January through October 1981, we screened blood and cerebrospinal fluid pneumococcal isolates from 101 patients in the Denver, Colorado area. Isolates from seven patients (6.9%) showed relative resistance to penicillin, with minimal inhibitory concentrations ranging from 0.12 to 1.0 microgram/ml. Two isolates (2.0%) were resistant to chloramphenicol, both with a minimal inhibitory concentration of 16 micrograms/ml. One of these was multiply resistant (to penicillin, chloramphenicol, and tetracycline). All isolates were susceptible to erythromycin, sulfamethoxazole-trimethoprim, and rifampin. On the basis of penicillin susceptibilities performed by participating hospitals on the isolates from 215 patients in the Denver area (101 included in the survey, 114 not included), we estimated the rate of relative resistance to penicillin to be approximately 4.3%. Compared with resistance rates reported in a previous study in Denver, these penicillin and chloramphenicol resistance rates may represent a trend of increasing resistance to these antibiotics in the Denver area. We recommend screening all isolates from invasive pneumococcal infections for penicillin and chloramphenicol susceptibility.

Nontuberculous mycobacterial disease following hot tub exposure.

Nontuberculous mycobacteria (NTM) have been recognized as an important cause of disease in immunocompromised hosts. Pulmonary disease caused by NTM is increasingly recognized in previously healthy persons. Investigation of pulmonary disease affecting a family of five identified an indoor hot tub as the source of NTM-related disease.