What sign of primary syphilis should a nurse expect to find in a female client?

In the case of primary syphilis, the classic sign is the appearance of a chancre, which is typically a small, indurated, and painless sore. In females, this lesion commonly appears on the vulva, although it can also occur in other genital areas. The chancre is the primary manifestation of syphilis and is a direct result of the Treponema pallidum bacterium entering the body and leading to localized infection.

While other symptoms, such as fever, malaise, rashes, and swollen lymph nodes, are associated with different stages of syphilis or other infections, they do not represent the hallmark feature of primary syphilis. Fever and malaise occur more prominently during the secondary stage, where systemic involvement is noted. Similarly, a body rash is also characteristic of secondary syphilis after the initial infection has progressed. Enlarged lymph nodes can present in various stages of syphilis but are not specific to primary syphilis.

Thus, the presence of an indurated painless nodule on the vulva serves to clearly identify the early stage of syphilis, which is critical for timely diagnosis and treatment.