Lymphangitis is an infection and inflammation of the lymph vessels. It can result from a bacterial skin infection. A person may notice red or dark streaks extending from the site of an injury, along with swelling, pain, and warmth.

Skin infections are the most common cause of lymphangitis. A person with lymphangitis may notice streaks on the skin. If the infection is in the hand, for example, the streaks will spread up the arm.

Treatment for lymphangitis will depend on the cause. It typically results from a bacterial infection, and the treatment is usually with antibiotics.

The lymphatic system features lymph vessels, similar to blood vessels, that carry lymphatic fluid throughout the body. If an infection occurs, lymphatic fluid carries lymphocytes — a type of white blood cell — to the infection site to help fight the infection.

If the lymph vessels become infected, lymphangitis can result.

In this article, learn more about the causes and symptoms of lymphangitis and how doctors diagnose and treat it.

People with lymphangitis may notice red streaks extending from the site of an injury to areas with a lot of lymph glands, such as the armpits or groin.

The streaks will:

  • appear red or darker than the surrounding skin on darker skin tones
  • be irregular in shape
  • feel warm
  • be tender or painful
  • spread from an infection site toward the lymph nodes, for example, up the arms towards the underarm

On darker skin, the streaks may be difficult to see, and doctors may need to base diagnosis on other factors, such as tenderness along the lymphatic routes.

Other symptoms of lymphangitis include:

Blood tests may show a high white blood count, known as leukocytosis.

Without treatment, the infection can spread to other parts of the body, leading to sepsis. Sepsis is an extreme reaction to an infection. It is a life threatening condition that can cause a high fever, flu-like symptoms, and even organ failure.

People with the following symptoms should seek urgent medical help, as they may indicate sepsis:

  • a rapid heart rate or weak pulse
  • confusion
  • severe pain
  • breathing problems
  • fever or chills
  • clammy skin or sweating

A person who feels very ill following an injury, or who has a high fever and symptoms of lymphangitis should seek emergency medical attention.

People with signs of skin infections who have these conditions should speak to their doctor.

What does it mean if you have swollen lymph nodes?

Lymphangitis occurs as a secondary infection. This means it happens because of another infection. If an infection travels from the original site to the lymph vessels, the vessels become inflamed and infected.

Bacterial infections are the most common cause of lymphangitis, but viral and fungal infections can also cause it.

It usually involves Staphylococcus aureus, but the bacteria may be streptococcal or gram-negative.

Any injury that allows a virus, bacteria, or fungus to enter the body can cause an infection that leads to lymphangitis.

Possible causes include:

  • puncture wounds, such as from stepping on a nail or other sharp object
  • untreated or severe skin infections, such as cellulitis
  • insect bites and stings
  • a wound that needs stitches
  • infected surgical wounds
  • sporotrichosis, a fungal skin infection that affects gardeners

People with a history of lymphedema or a weakened immune system have a higher risk of lymphangitis.

Having certain conditions, such as diabetes, HIV, or cancer, or taking drugs that suppress the immune system, including chemotherapy drugs, may all increase the risk.

What is an infected insect bite?

A doctor may suspect lymphangitis based on a person’s symptoms alone. If a person has swollen lymph nodes, red streaks extending from an injury, or other signs of infection, a doctor may begin treatment with antibiotics, even before test results are ready.

This will enable treatment to start as soon as possible.

Tests can help identify the cause of the infection so that the doctor can target the infection effectively. It will also enable them to provide treatment for any underlying problem.

When the test results are ready, a doctor may change the treatment or add further medication to the person’s treatment plan.

In some cases, a doctor might do a biopsy of any swollen lymph nodes to rule out other conditions. Blood work may also be helpful, especially if the cause of the infection is unclear.

Lymphangitis can spread quickly, so doctors typically recommend aggressive treatment of the underlying infection.

Most cases will need antibiotics as treatment. Intravenous (IV) antibiotics can deliver the medication faster, but a doctor may prescribe oral antibiotics if the risk does not appear to be high.

For a fungal or viral infection, a doctor will prescribe antifungal or antiviral medications.

If the infection persists after one course of treatment, the doctor may recommend another course. Rarely, an individual may need surgery to remove infected tissue.

Lymphangitis can be very painful. To help with the pain, a person can try:

  • applying warm compresses to the injury and areas with red streaks
  • using anti-inflammatory medications, such as ibuprofen
  • taking prescription-strength pain relievers from a doctor

Treatment aims to stop the infection from spreading. To assess whether treatment is working, a doctor may outline streaks with a marker or take pictures to see whether they contract or continue to spread following treatment.

If more streaks appear, a wound seems to get worse, or a person develops additional symptoms, it may be a sign that treatment is not working.

Recovering from lymphangitis can take days, but the recovery time will depend on how serious the infection was and the individual’s health status before it occurred.

Factors that can lengthen the recovery time include:

  • having a weakened immune system
  • older age
  • developing complications, for example, if lymphangitis affects skin, muscle, or other tissue

A person who has surgery to remove damaged tissue may need physical therapy after.

However, most people can return to their daily lives soon after a lymphangitis infection heals.

Some people develop recurrent lymphangitis. This is a type of chronic lymphangitis that goes away with treatment and then reappears later. It can happen if a person does not receive appropriate treatment for the original infection.

For example, if lymphangitis develops from athlete’s foot, it may return if the athlete’s foot does not respond to treatment.

People with weakened immune systems also have a higher risk of recurrent lymphangitis because it is harder for their bodies to fight off infections.

Here are some questions people often ask about lymphangitis.

What causes lymphangitis?

Lymphangitis usually results from an existing bacterial skin infection. This could be due to an insect bite, a wound, or another condition, such as cellulitis. It can also stem from an existing fungal or viral infection.

How do you know if you have lymphangitis?

Lymphangitis causes pain and streaks that spread away from the original infection site toward the lymph nodes, for example, from a wound on the hand toward the armpit. On lighter skin tones, the streaks will be red. On darker skin tones, they will be darker than the surrounding skin and may be difficult to see. The streaks may be tender and warm, and the person may also experience a fever and feel generally unwell.

Is lymphangitis an emergency?

Lymphangitis can spread quickly and lead to severe complications, so a person should seek medical help as soon as possible. Some people will need to spend time in the hospital. Anyone who receives treatment for lymphangitis as an outpatient should also receive follow-up 24–48 hours later.

Lymphangitis is an infection and inflammation of the lymph vessels. It usually spreads to the lymphatic system from a primary infection. The infection is usually bacterial but can be fungal or viral.

Anyone who has signs of lymphangitis should seek treatment at once. In some cases, not treating the infection can lead to severe complications, such as sepsis.