Sexually transmitted diseases aside, itchiness in the groin area can be a symptom of tinea cruris (also known as jock itch). Tinea cruris is a fungal infection of the skin of the groin.It is caused by spread from other areas (tinea pedis, or athlete's foot) by applying the same towel to both areas.exually transmitted diseases aside, itchiness in the groin area can be a symptom of tinea cruris (also known as jock itch). Tinea cruris is a fungal infection of the skin of the groin.