Inflammation Inflammation is the body's response to Persistent thrush on penis, irritation or injury, which causes redness, swelling, pain and sometimes a feeling of heat in the affected area. Skip to main content. This is because the infection can be spread or made worse during sex. Rare causes include Streptococcus pyogenes, Prevotella melaninogenica, Cordylobia anthropophaga, Providencia stuartii, and Pseudomonas aeruginosa, the last 2 in individuals who are immunocompromised. How can I tell if I have one?