Pap smear is useful in the diagnosis of all EXCEPT:
The Papanicolaou test (also called Pap amear, Pap test, cervical smear, or smear test) is a screening test to detect premalignant and malignant processes in the transformation zone.
Abnormal results are reported according to the Bethesda System. They include:
Squamous cell abnormalities (SIL)

A typical squamous cells of undetermined significance (ASC-US)
Low grade squamous intraepithelial lesion (LGSIL or LSIL)
A typical squamous cells cannot exclude HSIL (ASC-H)
High-grade squamous intraepithelial lesion (HGSIL or HSIL)
Squamous cell carcinoma

Glandular epithelial cell abnormalities

Endocervical and endometrial abnormalities can also be detected by pap smear
A number of infectious processes, including yeast, candidiasis, herpes simplex virus, and trichomoniasis can also be detected however, it is not very sensitive at detecting these infections, so absence of detection on a Pap does not mean absence of the infection.
Gonorrhoea
Trichomonas vaginalis
Human papilloma virus
Inflammatory changes