Abstract
Human immunodeficiency virus (HIV) causes breakdown of the immune system and predisposes patients to various opportunistic infections and neoplasms. However, many patients may not be aware of the HIV infection before the development of their first HIV related complications. We reported four unrecognised HIV patients presenting to our accident and emergency department with common complications of HIV infection and the acquired immunodeficiency syndrome (AIDS). Although not as common as in America, emergency physicians in Hong Kong still have to take care of patients with unknown HIV status. The common presentations of HIV patients will be discussed. A high index of suspicion and knowledge of common HIV/AIDS complications are required for managing these patients.