Article Text
Abstract
Introduction Novel approaches to combating drug-resistant N. gonorrhoeae infections are urgently needed. Targeted therapy with ciprofloxacin for susceptible infections has been made possible by the development of a rapid molecular assay for the determination of mutation in the gyrase A gene of N. gonorrheoae, which reliably predicts susceptibility to ciprofloxacin.
Methods Using previously collected data over a thirteen-month study period of all N. gonorrhoeae cases diagnosed to UCLA Health System, we determined the costs per-test of running the rapid genotypic gyrase A assay and treatment with 500 mg of ciprofloxacin for wild-type infections and compared these estimations with the costs of the standard of care treatment, which is empiric dual therapy with 250 mg ceftriaxone injection and 1000 mg azithromycin. Cost estimates for non-empiric therapy included assay reagents, labour, refrigerator space, and ciprofloxacin 500 mg. Cost estimates for empiric therapy included costs of ceftriaxone 250 mg, injection, azithromycin 1000 g, needle, syringe, and clinic space.
Results There were 167 non-empirically treated anatomic site-specific N. gonorrhoeae infections during the thirteen month study period, 51 (30.5%) of which were wild-type, and 49 (29.3%) were mutant. Using the total number of specimens tested (167) we calculated the cost of running the assay per specimen to be $97.4. With an additional cost of $2.2 per pill of ciprofloxacin, the total cost of non-empiric therapy for wild-type infections was estimated to be $99.6. The cost of empiric treatment with ceftriaxone and azithromycin was estimated to be $141, however there may be additional costs of up to $300 based on the clinic facility fees, which vary greatly by location.
Conclusion We found that the genotypic assay with ciprofloxacin therapy among wild-type infections is less costly than empiric therapy. Furthermore, given the consequences ceftriaxone resistance, including continued transmission and the sequela of untreated infection, the true difference in cost may be even greater.