koh-mount-for-fungal-diseases

What Is Potassium Hydroxide Mount?

The KOH mount procedure is commonly used in dermatology to quickly detect fungal elements in skin, hair, and nails.

KOH, an inexpensive and easily accessible alkali, acts as a strong base. It softens, digests, and clears cellular and keratin debris, effectively removing the background and enabling clear visualization of fungal hyphae under a microscope. The fungal cell wall remains intact and resistant to digestion by KOH, aiding in the identification of fungal elements.

Discuss the Historical Aspects of Koh Mount?

The use of the KOH mount for diagnosing superficial fungal infections has a history spanning over a century. Despite its long-standing use, there is no historical agreement on who pioneered the original KOH preparation, making the origins of this procedure a mystery.

What Are the Prerequisites for This Procedure?

The equipment used includes a glass slide, cover slip, scalpel, 10% KOH solution, Bunsen burner flame, and a microscope.

How Is 10% Potassium Hydroxide Prepared?

Prepare a 10% KOH solution by dissolving 10g of KOH crystals in 50 ml of distilled water, stirring until fully dissolved. Then, add 10 ml of glycerol to prevent drying. Finally, add more distilled water to reach a total volume of 100ml. Handle this solution with care as it is corrosive, and store it at room temperature.

What Are the Different Concentrations of Potassium Hydroxide Which Can Be Used for This Procedure?

Typically, 10% or 20% KOH solutions are utilized for skin and hair samples. However, for nail samples and thick hyperkeratotic specimens, a stronger concentration of 20%-40% KOH is employed.

What Is the Ideal Digestion Time or Clearing Time?

The digestion of cellular and keratin debris typically takes around 10-15 minutes. However, thicker hyperkeratotic samples may require 30 minutes to an hour for digestion. Nail and hair specimens may take 24-48 hours to clear completely.

How Can You Reduce the Clearing Time for Hair and Nail Specimens?

• Using a higher concentration of KOH, like 20% or 40%.
• Warming the slide prior to microscopic analysis.
• Mixing equal parts of 40% Dimethyl Sulfoxide (DMSO) with 10% KOH results in swift digestion of keratin. This enables prompt specimen examination without requiring slide heating.