Putrefaction Discoloration Explained

Putrefaction is the process of decomposition of organic matter, particularly proteins, by microorganisms. In the context of a dead body, this process leads to noticeable changes, including alterations in color.

Understanding Greenish Discoloration

Early putrefaction often involves a characteristic greenish discoloration. This color change is specifically linked to chemical reactions occurring within the body as tissues break down.

The Role of Sulphmethaemoglobin

The greenish discoloration observed in early putrefaction is primarily caused by the formation of Sulphmethaemoglobin. Here's how it happens:

• As decomposition begins, bacteria produce hydrogen sulfide (H₂S).
• This hydrogen sulfide reacts with hemoglobin present in the blood.
• Hemoglobin is a protein that carries oxygen. When it reacts with H₂S, it forms Sulphmethaemoglobin.
• Sulphmethaemoglobin is a greenish pigment. Its presence in the blood, which then diffuses into tissues, results in the characteristic greenish hue seen on the skin, often starting in the abdominal region.

Analysis of Other Options

Let's look at why the other options are not the primary cause:

• Oxyhaemoglobin: This is the form of hemoglobin that is bound to oxygen. It gives blood its bright red color and is present in living individuals, not directly responsible for the greenish color of decomposition.
• Biliverdin: Biliverdin is a green bile pigment. While it is green, it is typically associated with the breakdown of hemoglobin in bruises (echymosis) or certain pathological conditions, rather than being the direct cause of the *early putrefaction* greenish discoloration. It can be a later stage or secondary contributor, but Sulphmethaemoglobin is the principal agent in initial stages.
• Carbomethaemoglobin: This is a form of methemoglobin where carbon monoxide is bound. Methemoglobin itself is brownish, and while it represents an altered state of hemoglobin, Carbomethaemoglobin formation is not the specific cause of the initial greenish tint in putrefaction.

Therefore, the formation of Sulphmethaemoglobin due to the reaction of bacterial hydrogen sulfide with hemoglobin is the direct cause of the greenish discoloration in early putrefaction.