Alternative use of polymerase chain reaction instead of rho-nitro-alpha-acetylamino-beta-hydroxypropiophenone test for the early detection of Mycobacterium tuberculosis in BACTEC 12B cultures.

Compared with conventional culture media, the TB BACTEC system has demonstrated improved isolation rates as well as an earlier detection time for mycobacterial species. However, the identification of M. tuberculosis by the rho-nitro-alpha-acetylamino-beta-hydroxypropiophenone (NAP) test in the TB BACTEC 460 system may require 6 days for interpretable results. We evaluated the usefulness of a polymerase chain reaction (PCR) assay for earlier identification of M. tuberculosis in positive BACTEC 12B cultures. A total of 262 TB BACTEC culture specimens with GIs > or = 10 were assayed by PCR, and the results were compared with those of the NAP test. The aliquot from BACTEC 12B vials was boiled for 10 min, and 2 microliters of the boiled suspension was used for the PCR assay. One set of primers based on the IS 6110 sequence of M. tuberculosis was used to amplify a 457 bp fragment of DNA. Of the 173 TB BACTEC culture specimens which were identified as M. tuberculosis by the NAP test. 171 were PCR positive. Of the 21 TB BACTEC cultures identified as MOTT by the NAP test. 19 were PCR negative, but 2 were PCR positive: these two cultures were shown to grow both M. tuberculosis and MOTT in BACTEC 12B vials. Of the remaining 68 cultures which were contaminated with AFB-negative bacteria, the PCR identified M. tuberculosis in 13, in agreement with the NAP results in the reprocessed specimens. Overall, the PCR results in the 262 BACTEC culture specimens with GIs > or = 10 were sensitive in 99.5% (186/187) and specific in 100% (68/68). The mean time for the identification of M. tuberculosis in TB BACTEC cultures with GIs > or = 10 was 7 h by the PCR compared to 5.9 days by the NAP test. These results suggest that the PCR could be used as an alternative to the NAP test for the rapid identification of M. tuberculosis in BACTEC 12B cultures, particularly in those which contained both M. tuberculosis and MOTT or M. tuberculosis and AFB-negative bacteria.

An epidemiological study of hip fracture in Honam, Korea.

We have undertaken an epidemiological study of fractures of the hip which occurred in the Honam area of Korea during the year 1991. Honam comprises 3 districts, Kwangju, Chonnam, and Chonbuk. On November 1st 1991 the total population over the age of 50 years in Honam was 1,205,370. During the year there were 405 fractures of the neck or intertrochanteric region of the femur, an incidence of 3.4 per ten thousand per year. The age specific incidence rate showed a gradual increase. The incidence rate showed seasonal variations being higher in the summer and fall, and lower in the winter and spring. The incidence in urban areas was higher than in rural regions to a level which was statistically significant. The average age of patients was 70.2 years (range 50 to 94 years). The most common cause of injury was a simple fall (61%). There were 212 females and 193 males, a ratio of 1.1:1. There were 196 fractures of the neck and 209 of the intertrochanteric region. The degree of osteoporosis increased with age. About half of the patients (49.9%) showed definite osteoporosis, the degree being higher in women and in fractures of the neck of the femur. Treatment was by operation in 328 patients (81%); 77 patients were treated conservatively or had no treatment (19%). Of the 360 patients whose final outcome was known, 26 died within three months of injury, a mortality of 7.22%. The mortality was 3.8% (11 out of 292) in patients who underwent operation, whilst it was 22.1% (15 out of 68) in patients who were treated conservatively or remained untreated.(ABSTRACT TRUNCATED AT 250 WORDS)