Screening by culture for the detection of gonorrhoea in women

The number of gonoccal infections detected by each of three sets of diagnostic cultures from the urethra, cervix, rectum and occasionally the throat, were calculated for 1976 when Thayer Martin (TM) medium was used and for 1977 when Modified New York City (MNYC) medium was used. In 1977, 98.7 per cent (451/457) of the total infections diagnosed were confirmed by culture compared with 88.3 per cent (324/367) of infections diagnosed in 1976 (P less than 0.001). The first set of diagnostic tests detected 97.6 per cent (440/451) of culture-positive infections in 1977 compared with only 88.9 per cent (228/324) in 1976 (P less than 0.001). The efficiency of screening with a single endocervical culture was also calculated. This procedure would have detected 90.2 per cent (407/451) of culture-positive infections in 1977 when MNYC medium was used compared with only 78.1 per cent (253/324) in 1976 when TM medium was used (P less than 0.001). It is suggested that the statistically significant improvement in the culture results for 1977 resulted from the introduction of MNYC medium since all other diagnostic procedures were identical to those in 1976. Other advantages associated with the use of MNYC medium are discussed.