As a registered clinical laboratory scientist, I’ve learned that there are certain medical conditions that are actually perceived as a myth or folklore. For instance, the existence of Vampires or vampirism, which most people think is just a work of fiction.

In a new study published in the journal Proceedings of the National Academy of Sciences, researchers found a link between vampirism and the rare genetic blood disorder known as Erythropoietic protoporphyria (EPP). According to Manorama, people suffering from this condition experience skin blisters when exposed to sunlight.

What is EPP?

One of the most interesting subjects I studied in college was hematology and under this field of study is the topic, erythropoietic protoporphyria (EPP). I even remember how our professor told us that the existence of vampires could be due to this condition, but what exactly is EPP?

Considered to be the third most common blood disorder under the classification of porphyrias and the most common in childhood, EPP is a “rare inherited metabolic” condition marked by a deficiency of the ferrochelatase (FECH) enzyme or mutations of the FECH gene.

It is also inherited as an “autosomal dominant genetic trait with poor penetrance” and the condition is characterized by “abnormally elevated levels of protoporphyrin IX” in the red blood cells (erythrocytes), bone marrow and blood plasma, the National Organization for Rare Disorders noted.

Symptoms and complications

EPP’s major symptom is hypersensitivity of the skin to sunlight and other types of artificial light, which is often noticed in early childhood and occurs throughout life.

According to the American Porphyria Foundation, the condition is usually characterized by a “very painful photosensitivity,” in which exposure to sunlight could lead to the redness, itching, swelling or burning of the skin.

Moreover, affected individuals could also exhibit edema, which refers to the abnormal accumulation of body fluids and/or erythema or the persistent redness or inflammation of the skin.

In rare cases, some individuals may develop hyperpigmentation, “sac-like lesions” and scars.

People with EPP could also suffer complications associated with the gallbladder and liver function. In fact, an interruption in the flow of bile through the gallbladder and bile ducts known as cholestasis could occur. In rare instances, EPP patients are also at risk for developing liver damage or failure.

Vampire connection

Due to the various genetic mutations affecting the heme production, the clinical presentations of porphyrias also varied. According to the researcher, these presentations are linked to the folklore of vampirism, which is often romanticized in fictional movies and novels.

It is already a known fact that vampires are sensitive to light, which people with EPP also suffer.

Boston Children’s Cancer and Blood Disorders Center’s Barry Paw also explained that EPP-affected individuals are “chronically anemic,” which make them appear “very pale” and feel “very tired.”

Due to increased photosensitivity, EPP patients are not able to expose themselves during the day. These characteristics are related to how these blood-sucking vampires are described in Hollywood movies, novels, myths, and folklore.

Staying indoors during daytime and receiving blood transfusions that contained adequate heme levels can help ease some of the symptoms of the disorders. Researchers noted that drinking animal blood and going out only at nighttime during ancient times could also have fueled the concept of vampires. So, does the connection between EPP and vampirism make sense now?