Which tool is primarily used to diagnose ringworm?

The tool primarily used to diagnose ringworm is the Wood's lamp. This device emits ultraviolet (UV) light, which can cause certain fungi, including those responsible for ringworm, to fluoresce. When a patient suspected of having ringworm is examined under a Wood's lamp, areas affected by the fungal infection may glow, providing a visual indication of the presence of the organism.

This is particularly useful as a preliminary screening tool because it is non-invasive and can quickly help in identifying potential infections. While a definitive diagnosis of ringworm typically requires additional testing, such as fungal culture, the Wood's lamp serves as a helpful first step in the diagnostic process for this common dermatophyte infection in both animals and humans.

Other tools listed, such as binoculars, a dermatoscope, and ultrasound, are not specialized for diagnosing fungal infections like ringworm. Binoculars are used for distant viewing and not applicable in a veterinary diagnostic setting. A dermatoscope aids in examining skin lesions and conditions more closely, but it does not provide the specific fluorescence needed to confirm a ringworm diagnosis. Ultrasound is used for imaging internal structures and is not relevant for diagnosing skin conditions. Thus, the Wood's lamp stands out as the primary diagnostic tool for