What are the reasons why candidiasis is not cured?

Patient's question:

Itching of the external genitalia after menstruation, everything else is normal, a year ago

Doctor's answer:

Analysis of the condition: It can. Generally, Candida albicans can in the human mouth-pharynx, intestines, skin, and vaginal mucosa, coexisting peacefully without causing disease. However, when the body's resistance declines, or severe diseases are present, with combined B vitamin deficiency, or long-term use of immunosuppressants, it can take advantage of the weakened state. Patients with diabetes or pregnant women have increased glycogen content in vaginal epithelial cells, which increases vaginal acidity, favoring the growth and reproduction of Candida and leading to the onset of the disease. Additionally, excessive use of antibiotics disrupts the vaginal flora, alters the vaginal environment, and can also cause candidal vulvovaginitis. In daily life, poor hygiene habits, such as wiping from the anus toward the urethra after using the toilet with toilet paper, can transfer intestinal Candida to the external genitalia, causing inflammation. Washing underwear with socks, sharing bathtubs with patients of candidal vulvovaginitis, or borrowing others' underwear can also lead to cross-infection.
Guidelines for treatment: For candidal vulvovaginitis, first rinse the external genitalia and vagina with alkaline solutions such as 2–4% sodium bicarbonate or soap water to alter the vaginal pH, making it unfavorable for Candida growth. After rinsing, insert Nystatin tablets or suppositories into the vagina, with a dose of 100,000–200,000 units per time, once daily, for a course of 10–14 days. Then, apply 3% miconazole ointment to the external genitalia for better results. For stubborn cases, oral ketoconazole or clotrimazole can be taken to eliminate intestinal Candida, or topical miconazole can be used. During treatment, sexual intercourse should be avoided, underwear should be changed and washed daily, and boiled for disinfection. After one course of treatment, if the Candida test is negative, follow-up tests should be negative after each menstrual cycle. Continuous consolidation treatment for three courses is required to confirm cure. It is best for the male partner to undergo treatment as well. Shoes and socks should be washed separately from underwear. Condoms are recommended during intercourse to prevent recurrence. Otherwise, it is easy to relapse. The reasons for recurrence are generally incomplete treatment and reinfection from the sexual partner.