Infectious diseases are disorders caused by organisms such as bacteria, viruses, fungi, or parasites.

They can be transmitted through direct contact with an infected person, animal, insect bites, or contaminated food and water.

Symptoms vary but often include fever, fatigue, muscle aches, cough, and digestive issues.

Diagnosis involves physical examinations, medical history review, and diagnostic tests such as blood tests, cultures, and imaging.

Treatments may include antibiotics, antivirals, antifungals, antiparasitics, and supportive care depending on the type of infection.

Types include flexible cystoscopy, rigid cystoscopy, and retrograde cystoscopy, each used 

based on the diagnostic or therapeutic needs.

Common reasons include chronic sinusitis, nasal polyps, blocked sinus passages, and recurrent sinus infections that do not respond to other treatments.