Final answer:
The likely diagnosis for the expanding rash is a fungal infection that was initially treated like eczema. Antifungal medications are usually effective for most fungal infections.
Step-by-step explanation:
The likely diagnosis for the expanding rash in the student's case is a fungal infection that was initially treated as eczema with a steroid. Fungal infections of the skin, such as ringworm, can present with a red, itchy rash that can spread if not properly treated. It is important to correctly identify the fungus causing the infection in order to provide appropriate treatment.
The treatment for fungal infections of the skin usually involves the use of antifungal medications. Topical antifungal creams or ointments are commonly used and are usually effective for most fungal infections. However, if the initial treatment with a steroid cream did not work and the rash is expanding, it is possible that the fungus causing the infection is resistant to the steroid.
It is recommended that the student seek medical attention to have the rash re-evaluated and properly diagnosed. The doctor may need to take a scraping of the rash for examination under the microscope to identify the specific species of fungus causing the infection. Based on the diagnosis, the doctor can prescribe the appropriate antifungal medication to effectively treat the fungal infection.