What are the other Names for this Condition? (Also known as/Synonyms)

• Dengue Fever causing Enlarged Lymph Nodes
• Dengue Fever Lymphadenitis
• Enlarged Lymph Nodes due to Dengue Fever

What is Dengue Fever Lymphadenopathy? (Definition/Background Information)

• Dengue Fever Lymphadenopathy is the inflammation and enlargement of lymph nodes due to underlying Dengue Fever, which is caused by a virus
• Dengue Fever is generally endemic to certain tropical and subtropical regions of the world such as South East Asia, Western Pacific Islands, the Caribbean region, Central and South America, Australia, and Africa
• Dengue Fever Lymphadenopathy is a vector-borne disease transmitted by mosquito bites. It can affect individuals of all ages, whether male or female. A majority of the infected individuals do not show any signs or symptoms
• The signs and symptoms of Dengue Fever Lymphadenopathy include enlarged lymph nodes that are not painful. Often, the groin and head and neck lymph nodes are involved
• The underlying Dengue Fever may be mild to moderate and can cause nausea and frequent vomiting, fever, body rash, and joint and muscle pain. In severe cases, there can be bleeding from the gums and nose
• Treatment is based upon the symptoms and may include adequate bed rest and medication. The prognosis of Dengue Fever Lymphadenopathy generally depends upon the severity of the underlying signs and symptoms due to Dengue Fever infection
• In a majority of cases, the underlying Dengue Fever has excellent prognosis and most individuals recover within a couple of weeks

Who gets Dengue Fever Lymphadenopathy? (Age and Sex Distribution)

• Dengue Fever Lymphadenopathy occurs due to underlying Dengue Fever, which can affect individuals of all ages, both genders (males and females), and all racial and ethnic groups
• However, Dengue Fever is more prevalent in certain geographical regions of the world, such as the South East Asia and Western Pacific Islands (per World Health Organization)

What are the Risk Factors for Dengue Fever Lymphadenopathy? (Predisposing Factors)

The main risk factor for Dengue Fever Lymphadenopathy is the underlying Dengue Fever. The risk factors for Dengue Fever may include:

• Living in or traveling to tropical and subtropical regions, especially during summers, when mosquito breeding is at its peak. These regions include South East Asia, Western Pacific Islands, the Caribbean region, Central America, South America, Australia, and Africa
• Lack of proper anti-mosquito precautions
• Outdoor camping and other outdoor activities that exposes one to mosquito bites

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases one’s chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Dengue Fever Lymphadenopathy? (Etiology)

• Dengue Fever Lymphadenopathy is caused by an RNA virus belonging to the Flaviviridae family. This viral disease is caused by any one of 4 similar Dengue viruses:
  • DENV 1
  • DENV 2
  • DENV 3
  • DENV 4
• It is usually transmitted to humans by the bite of an infected mosquito. In the western hemisphere, the Aedes aegypti mosquito is the most important transmitter of Dengue viruses

What are the Signs and Symptoms of Dengue Fever Lymphadenopathy?

The signs and symptoms of Dengue Fever Lymphadenopathy may include:

• Lymphadenopathy or enlarged lymph nodes that are more commonly seen on the inguinal (groin) region and head and neck region
• Other lymph nodes of the body may also be affected
• There may not be any pain associated with the swollen lymph nodes

Note: A majority of individuals do not experience any symptoms of Dengue Fever Lymphadenopathy when infected by the virus.

The associated signs and symptoms of Dengue Fever may include:

• Fatigue
• Skin rashes all over the body; but usually on the chest, stomach, and back
• Joint pain (arthralgia) affecting the wrist, knee, and ankle; sometimes, it can affect the fingers and toes
• Swelling of multiple joints due to fluid accumulation, causing joint stiffness
• Muscle pain (myalgia)
• Blood in urine
• Symptoms begin between 4-7 days after being infected

There are 3 phases of Dengue Fever infection. The enlargement of lymph nodes occurs in the first phase or the ‘fever phase’. The 3 phases include:

Phase 1: Fever phase

• Symptoms of the fever phase include high fever that can last for up to a week
• This is accompanied by body aches, headache, skin rash, swelling of the lymph nodes, continuous vomiting, intense abdominal pain, difficulty breathing, and severe bleeding
• There may be symptoms of shock also

Phase 2: Critical phase

• The critical phase usually begins when the fever goes away and can last for up to 2 days
• It would appear that the condition is getting better; however, it may not be the case
• In the critical phase, the blood pressure can suddenly drop and the individual may go into deep shock. This can result in death in spite of all treatment measures
• Also, several organs may get damaged, affecting their function

Phase 3:  Convalescent phase

• During the convalescent phase, the individual starts to get slowly better
• The skin rashes may start healing, which can cause intense itching

How is Dengue Fever Lymphadenopathy Diagnosed?

Dengue Fever Lymphadenopathy is diagnosed using the following methods:

• A thorough physical examination and a complete medical and travel history (including travel history to tropical and subtropical regions)
• Complete blood count with peripheral smear examination
• Tests to diagnose underlying Dengue Fever may include:
  • Blood test(s) to specifically detect Dengue Fever infection. The blood tests may show decreased platelet count, decreased white cell count, and increased erythrocyte sedimentation rate (ESR)
  • Liver function test may show increased liver enzymes such as aspartate aminotransferase (AST) and alanine aminotransferase (ALT)

In majority of the cases, a lymph node biopsy is not performed for Dengue Fever Lymphadenopathy. However, if the signs and symptoms persist despite suitable treatment, then a biopsy may be undertaken to rule-out other causes of swollen glands (such as a lymphoma).

In case of a lymph node biopsy, the following information may be noted:

• Lymph node biopsy: A lymph node biopsy is performed and sent to a laboratory for a pathological examination. The pathologist examines the biopsy under a microscope. After putting together clinical findings, special studies on tissues (if needed) and with microscope findings, the pathologist arrives at a definitive diagnosis. The pathologist may use special techniques, such as immunohistochemistry stains, to help reveal the presence of the pathogen
• The lymph node biopsy may be performed through any of the following procedures:
  • Fine needle aspiration biopsy (FNAB): A device called a cannula is used to extract tissue or fluid from the lymph nodes
  • Lymph node core biopsy of the enlarged lymph node
  • Lymph node open biopsy of the enlarged lymph node

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Dengue Fever Lymphadenopathy?

Complications due to underlying Dengue Fever causing Lymphadenopathy may include:

• Prolonged enlargement of the lymph nodes raising a concern for malignant conditions such as lymphomas
• Prolonged signs and symptoms that can last several months
• 5% of individuals infected can have severe infection, which may be life-threatening

How is Dengue Fever Lymphadenopathy Treated?

Currently, there is no cure for Dengue Fever Lymphadenopathy. The treatment measures to alleviate the symptoms include:

• Adequate bed rest
• Medication such as analgesics (pain-relievers)
• Drinking plenty of fluids

With appropriate treatment, the swollen lymph nodes and other signs and symptoms of the condition should get better.

How can Dengue Fever Lymphadenopathy be Prevented?

Preventive methods for Dengue Fever Lymphadenopathy include taking adequate precaution from mosquito bites to avoid Dengue Fever. There is currently no vaccination available against Dengue Fever. The following measures are useful in controlling transmission of the condition:

• Sleeping under insecticide-treated mosquito nets is highly recommended in endemic areas
• Use of mosquito repellent creams. It is also advisable to cover your skin by wearing clothes, such as full-length pants, full-sleeved shirts, etc.
• Maintain good sanitary conditions, to prevent mosquitoes from breeding. When possible, eliminate all potential mosquito habitats that contain standing water, where mosquitoes breed and lay their eggs, such as water contained in temporary pools, old tires, discarded vessels, birdbaths, pots, rainwater puddles, etc.
• Sprays containing permethrin can be used on clothes; sprays containing DEET can be used on the skin
• Individuals who travel from a non-endemic region to Dengue Fever endemic region have to ensure that they are aware of the risk factors and avail basic preventive methods

Exposure to mosquito bites may be reduced, if one is aware of the biting patterns of the mosquitoes. The Dengue Fever-transmitting mosquitoes are most active during twilight and night. Avoiding outdoors to the extent possible or employing preventive actions during peak ‘biting’ hours may reduce risk.

What is the Prognosis of Dengue Fever Lymphadenopathy? (Outcomes/Resolutions)

The prognosis of Dengue Fever Lymphadenopathy is based on the severity of the underlying Dengue Fever infection.

• With suitable treatment, the prognosis of Dengue Fever is generally excellent; most of the infected individuals recover from the condition within a couple of weeks
• The underlying Dengue Fever may cause complications during pregnancy by affecting the developing fetus; however, information on the same is currently limited

Note: Dengue Fever has 4 distinct, yet closely-related viruses known as DEN-1, DEN-2, DEN-3, and DEN-4. If any one type of Dengue virus infects an individual, then infection with the virus once, confers lifetime immunity to the individual. However, having immunity to one type of Dengue Fever virus does not imply protection from the other 3 virus types.

Additional and Relevant Useful Information for Dengue Fever Lymphadenopathy:

• Dengue Fever is now a reportable disease in the United States. It is leading cause of fever in travelers returning from Asia, the Caribbean and Latin America. Transmission has occasionally occurred in the continental United States in areas where the Aedes mosquitoes are found
• It has been noted that this viral infection is not seen in altitudes above 4500 feet

General information on lymph nodes:

The lymph nodes are part of one’s immune system. The lymph nodes are present throughout the body, usually in groups. In normal healthy adults, one cannot feel (see or touch) the lymph nodes readily. However, if they are enlarged, they can be felt either by the individual himself/herself or by the healthcare provider.

Enlarged lymph nodes can occur in both benign and malignant conditions. Hence, the cause of enlarged lymph nodes should be evaluated. If no obvious cause for enlargement of lymph nodes is found, then the possibility of a lymph node malignancy should be ruled out.

In a majority of individuals, a lymph node swelling is caused by a benign process such as an inflammation or infection. In many cases, swollen lymph nodes are part of other signs and symptoms. This can help a healthcare provider arrive at a list of follow-up tests and ensure an accurate diagnosis. Superficial enlarged lymph nodes can be felt by the healthcare provider through palpation. Enlarged lymph nodes deep in the body are often detected by radiological studies such as X-rays, ultrasound scan, CT and MRI scans.

Some enlarged lymph nodes can be painful, while others may be painless. Depending upon the underlying cause, enlarged lymph nodes can be localized to a particular area of the body, or they can be generalized, meaning that they are present throughout the body.