Overview

Fournier gangrene is a rare but deadly infection, it affects the genitals and perineal (the region between the anus and genitals) regions. It is a rapid, progressive infection that requires emergency surgery, such as surgical debridement to remove dead tissue and treatment with antibiotics. Symptoms of this infection are swelling of the affected areas, severe pain, fever, general discomfort (malaise), nausea, vomiting, tissue damage, urinary retention, tenderness and itching. While there is no specific way to prevent Fournier gangrene, there are known approaches to minimise your risk of getting the disease.¹ These, as well as the causes of Fournier gangrene, will be discussed in this article. Understanding the causes and risk factors is important to protect your health and reduce the likelihood of contracting Fournier gangrene.

What Causes Fournier Gangrene?

Fournier gangrene starts with a bacterial infection, caused by different types of bacteria. They involve a mixture of aerobic (oxygen-needing) and anaerobic (non-oxygen-needing) bacteria, called a polymicrobial infection.¹ The disease has an average of four bacterial organisms per infection, the most common organisms are Escherichia coli, Staphylococcus, Streptococcus, Pseudomonas, Proteus and Bacteroides.² Most of these organisms are a part of the human microbiota which means they naturally co-exist within the skin, lungs or gut, impact processes within the body, and contribute to a healthy individual.³ To cause an infection, bacteria must enter the body through an entry point, such as a break in the skin. Some of these entry points are:

• Local skin trauma: This can be from mere cuts, scrapes and wounds. Pimples, insect bites and genital piercings can also create an entry point²
• Surgical acquired infection: Bacteria can enter the body during procedures such as rectal or anal surgery and surgery of the penis and scrotum⁴
• Urinary tract infection: The infection in the urinary tract can spread to surrounding tissue and infect the genitals and perineal regions
• Use of a catheter: Bacteria can enter the body through a catheter, which is a tube inserted into the bladder to empty it and collect urine⁵
• Anal and perianal conditions: These include perianal abscess or haemorrhoids that become infected and spread to surrounding tissue²

Once the infection in the appropriate region for Fournier gangrene to emerge is introduced, the bacteria produce toxins (poisons released by bacteria), which cause blood clots to form in the blood vessels. This leads to the death of cells and a shortage of blood supply to the tissue, resulting in a lack of oxygen to the infected tissue. The lack of oxygen promotes the growth of anaerobic bacteria which do not require oxygen to survive, these tend to be dangerous organisms that produce harmful gas and proteins, causing further death of cells. The death of cells is called necrosis, thus Fournier gangrene is classed as a type of necrotising fasciitis, also known as a flesh-eating disease of the soft tissue and facia.² Over time this process increases, resulting in further necrosis and spread into nearby areas.   

Importance of Spotting Fournier Gangrene at an Early Stage

Since Fournier gangrene starts in the facia, which is deep tissue within the genitals and perineal regions, it means that the initial infection is not visible to the naked eye. Necrosis of the tissue progresses quickly and within a short time frame, the infection can spread and cause the death of the tissue on the outer layer of the skin. Therefore, the disease may initially go unnoticed or unrecognisable due to minimal or no skin change in appearance.² This is a factor that contributes to the disease’s high mortality rate.¹

It is important to recognise the early symptoms to seek medical attention immediately, this is because you may start feeling some symptoms 2-7 days before you notice any physical changes to the appearance of the infected area. Typically, lethargy (a lack of energy) and fever may be present at first, followed by low blood pressure, tachycardia (abnormally fast heart rate) and severe genital pain. If these are noticed, medical attention is required urgently. Later, physical signs of Fournier gangrene may be present, such as discolouration, redness, blistering, swelling of tissue, and itchy outer skin. An indication of the presence of anaerobic bacteria is odour and the presence of subcutaneous crepitus, which is a crackling sound under the skin due to gas formation.²

What are The Risk Factors of Fournier Gangrene?  

Gender and Age

Fournier gangrene can occur in all genders, however, it is more likely to occur in males, with a 10 to 1 ratio. Having said this, women are more likely to suffer greater symptoms for longer. Likewise, it can affect people of all ages, however it is most common in people over 50. The likely cause of this is due to a weaker immune system in older people, which means their ability to fight off infections is lower than in younger people.¹

Chronic Health Conditions

Fournier gangrene can appear in healthy individuals, although those who are immunocompromised or suffer certain chronic health conditions have an increased risk of developing the disease. This is due to their weaker immune system, which cannot fight infections as well. These individuals typically have a higher mortality rate than healthy individuals who develop Fournier gangrene. Examples of these are:

• HIV/ AIDS
• Diabetes
• Cancers, such as prostate cancer and leukaemia
• Perianal abscess
• Kidney disease
• Cardiac (heart disease)
• Malnutrition
• Inflammatory bowel disease

These conditions have a common factor, which is a weakened immune system.¹

Diabetes

Diabetes is a common disease with two major types, type 1 and type 2, it is caused by the body’s inability to produce a normal amount of insulin by the pancreas or the inability to use insulin correctly, depending on the type.⁶ This results in not being able to maintain a normal blood sugar level. 20% to 70% of Fournier gangrene cases are of those with diabetes,¹ this is because people with diabetes are more likely to get infections and are unable to fight off infections as well as healthy individuals. High sugar levels in the body trigger the immune system to work harder, it causes inflammation around organs which, over time, damages them.⁷ This makes it more likely that people with diabetes will develop Fournier gangrene and struggle to fight it and heal wounds at a normal rate.

Recent studies have shown that taking sodium-glucose cotransporter 2 inhibitors (SGLT2i), a medication used to treat type 2 diabetes, has been linked to having an increased risk of developing Fournier gangrene. SGLT2i makes the kidneys remove more glucose from the body into the urine, this makes the likelihood of developing an infection in the urinary tract higher. In 2018, the US Food and Drug Administration warned patients who were taking SGLT2i to seek medical attention if they started to experience symptoms such as pain in the genitals.⁸

Lifestyle Factors

• Alcoholism: Excessive alcohol consumption may cause chronic liver failure and disrupt immune system pathways in the body, making it more difficult to defend against infections and slowing the recovery time of tissue damage from injury⁹
• Smoking: Within the lungs, smoking causes the immune response to be overworked and for the rest of the body, the nicotine reduces the immune system function, making it both easier to acquire infections and more difficult to defend against them¹⁰
• Drug abuse: The use of non-sterile or dirty needles to inject drugs can introduce potentially harmful bacteria into the bloodstream¹¹
• Poor hygiene: Not maintaining good hygiene and skincare can increase the risk of developing Fournier gangrene¹

Complications and Outcomes of Fournier Gangrene

Due to the nature of Fournier gangrene being a rapid and progressive infection, if medical attention is not sought out quickly, patients may suffer associated complications. These complications include:

• Sepsis
• Multiple organ failure
• Diabetic ketoacidosis - a condition that results in the body breaking down fat for fuel, producing ketones, or acids. As a result, the blood becomes acidic
• Kidney injury
• Prolonged hospital admission² 

Summary

Fournier gangrene is a life-threatening infection that is located in the genitals and surrounding areas. It is a rapidly progressing infection with symptoms such as severe pain in the genitals, fever, tissue damage and swelling of the infected regions. Fournier gangrene requires immediate medical attention, otherwise, complications may arise, such as sepsis and organ failure. The infection is caused by bacteria that enter the body through various means and although anyone can develop Fournier gangrene, it is mostly common in males over 50 years of age, patients with diabetes, individuals with poor hygiene, immune-compromised individuals with chronic health conditions, smokers and excessive alcohol consumers. Understanding the risk factors is important to know how to prevent Fournier gangrene and although this disease is severe, it is curable through antibiotics and surgery to remove dead tissue.