The hanging drop preparation is a quick microscopic technique used to observe motility of organisms in fresh stool.

It is especially useful for detecting Vibrio cholerae, which shows characteristic darting motility.

Clinical uses include:

Rapid diagnosis of cholera in suspected outbreaks.

Differentiating motile vs. non‑motile organisms in stool samples.

Supporting epidemiological investigations in endemic areas.

Often performed alongside stool culture, Gram stain, and serological tests for confirmation.

Analyte: Motile organisms in stool (primarily Vibrio cholerae).

Normal Result: No motile pathogenic organisms detected.

Abnormal Findings:

Positive hanging drop: Presence of motile Vibrio cholerae (darting motility).

Other motile bacteria: May indicate enteric infection.

Clinical Use:

Provides a rapid, bedside diagnostic tool for cholera.

Helps guide early treatment and outbreak control measures.

Supports infectious disease and public health evaluations.