Name of the Procedure:

• Common Name: Potassium Hydroxide Preparation
• Medical Term: KOH Preparation, HCPCS Code Q0112

Summary

Potassium hydroxide (KOH) preparation is a simple diagnostic test typically used to diagnose fungal infections on the skin, hair, or nails. A sample from the affected area is collected and treated with a potassium hydroxide solution, which helps to identify the presence of fungal elements under a microscope.

Purpose

• Medical Conditions: Diagnoses dermatophytosis (ringworm), candidiasis, tinea infections, and onychomycosis (nail fungus).
• Goals: Confirm the presence of fungal elements for appropriate treatment.

Indications

• Symptoms: Itchy, red, scaly patches on the skin; discolored, thickened, or brittle nails.
• Conditions: Persistent or recurrent skin rashes, suspected fungal infections.
• Patient Criteria: Any individual with symptoms suggestive of a fungal infection.

Preparation

• Pre-procedure Instructions: Typically, no special preparation is required. Patients may be asked to avoid applying lotions or creams on the affected area before the test.
• Diagnostic Tests: No additional tests are generally necessary before a KOH preparation.

Procedure Description

1. Sample Collection: The healthcare provider collects a small sample from the affected area using a scalpel, nail clipper, or swab.
2. Solution Application: The sample is placed on a slide and treated with a few drops of 10-20% KOH solution.
3. Microscopic Examination: The slide is then gently heated and examined under a microscope. The KOH solution dissolves keratin, making fungal elements like hyphae and spores more visible.

• Tools: Scalpel or blade, slide, coverslip, KOH solution, microscope.

Duration

The entire procedure takes approximately 10-15 minutes.

Setting

The KOH preparation is usually performed in outpatient clinics, dermatology offices, or healthcare centers.

Personnel

This procedure is generally performed by dermatologists, primary care physicians, or trained nurses.

Risks and Complications

• Common Risks: Minor discomfort or irritation at the sample collection site.
• Rare Risks: Infection or bleeding, though these are uncommon and generally easy to manage.

Benefits

• Rapid Diagnosis: Results can often be available during the same visit.
• Basis for Treatment: Confirms the presence of fungal infection, allowing for targeted treatment.

Recovery

• Post-procedure Care: Minimal care needed, keep the sample site clean and dry.
• Recovery Time: Immediate; there are no major restrictions post-procedure.
• Follow-up: As advised by the healthcare provider, typically depends on the results and treatment plan.

Alternatives

• Fungal Culture: Takes longer to yield results but can identify specific fungal species.
• PCR Testing: More expensive and sophisticated, but can provide detailed fungal identification.
• Skin Biopsy: Involves removal of a small skin sample for more extensive testing.

Patient Experience

• During Procedure: Mild discomfort during sample collection, particularly if using a blade or scalpel.
• After Procedure: Generally, no significant pain; patients might experience slight soreness or redness at the sample site, which usually resolves quickly. Pain management is generally not required, but over-the-counter analgesics can be used if needed.