Urinary mycobacterium avium presenting as sterile pyuria.

Area of Science:

• Urology
• Infectious Diseases
• Microbiology

Background:

• Sterile pyuria, the presence of white blood cells in urine without bacterial growth, can indicate various underlying conditions.
• Mycobacterium avium complex (MAC) is an opportunistic pathogen typically associated with immunocompromised individuals.

Purpose of the Study:

• To investigate the cause of persistent, asymptomatic sterile pyuria in a healthy adult.
• To identify the specific microorganism responsible for the urinary findings.

Main Methods:

• Analysis of urine samples for bacterial and fungal cultures.
• Tuberculosis and nontuberculosis mycobacterium species testing using first-morning urine samples.
• Genotypic identification of mycobacterial species.
• Mantoux skin testing.
• Urological imaging via ultrasound and computed tomography (CT).

Main Results:

• Urine cultures were negative for bacteria and fungi.
• Genotypic identification confirmed Mycobacterium avium complex (MAC) in urine samples.
• Mantoux skin testing was positive.
• No urological abnormalities were detected on imaging studies.

Conclusions:

• Mycobacterium avium complex (MAC) can cause persistent, asymptomatic sterile pyuria in otherwise healthy individuals.
• Diagnosis requires specific mycobacterial testing beyond routine urine cultures.
• This case highlights the importance of considering atypical infections in unexplained sterile pyuria.