Medial Iliac Lymph Nodes In Dogs: Causes, Symptoms, and Treatment

Medial iliac lymph nodes in dogs are located in the lower abdomen near the bladder and reproductive organs.

They’re part of a larger network of lymph nodes that help to fight infection and keep your pup healthy.

Unfortunately, these lymph nodes can sometimes become enlarged or swollen due to infection, cancer, or other medical conditions.

In this blog post, we’ll discuss the causes, symptoms, and treatment options for medial iliac lymph nodes in dogs.

Key Takeaway

• The function of the medial iliac lymph nodes in dogs is to drain the lymphatic fluid from the colon, rectum, reproductive organs, urinary bladder, and urethra, while also playing a vital role in the dog’s immune response by protecting the body against antigens.
• The medial iliac lymph nodes in dogs are located between the deep circumflex iliac arteries cranially and the external iliac arteries caudally, lateral to the aorta, usually ventral to the bodies of the 5th and 6th lumbar vertebrae.
• The size of medial iliac lymph nodes in dogs typically ranges from 2 to 4 cm in length, with an average length of 13.6 mm and width of 4.4 mm, as observed through ultrasonography.

The Function of Medial Iliac Lymph Nodes In Dogs

The medial iliac lymph nodes in dogs have an essential role in the canine lymphatic system.

They are parietal nodes that drain several areas including the colon, rectum, reproductive organs, urinary bladder, and urethra.

These nodes protect the body against antigens, remove interstitial fluids to return them to the circulatory system and trigger immune responses when necessary.

When the body is invaded by viruses or bacteria, or when a disease triggers an immune response, the medial iliac lymph nodes may become enlarged as they work to fight off the invader.

Ultrasonography is often used as a tool to assess these nodes in dogs, especially in diagnosing various conditions.

See also: What Is a Reactive Lymph Node In Dogs?

Where Are Medial Iliac Lymph Nodes Located In Dogs

The medial iliac lymph nodes in dogs are usually located ventral to the bodies of the 5th and 6th lumbar vertebrae and ventromedial to the lumbar muscles.

They can be found between the deep circumflex iliac arteries cranially and the external iliac arteries caudally, along the lateral margins of the origins of the left and right external iliac arteries.

These nodes are also positioned near the angle between different muscle groups and are consistently observed as large lymph nodes in situ.

See also: What Do Dog Lymph Nodes Feel Like?

Size of Medial Iliac Lymph Nodes In Dogs

The mean length of the medial iliac lymph node is approximately 13.6 mm, with a range of 7.2-27.8 mm, and the mean width is around 4.4 mm, within a range of 1.9-8.2 mm.

However, this can differ based on the size of the dog. In larger dogs, the medial iliac lymph nodes are typically 2 to 4 cm in length.

They appear fusiform to oval in shape when viewed through ultrasonography.

See also: Can Dogs Lymph Nodes Swell From Allergies?

Where Do The Medial Iliac Lymph Nodes Drain To?

The medial iliac drain lymph vessels from the skin of the dorsal half of the part of the abdominal wall located causally.

The drainage from these nodes is then directed toward the common iliac nodes.

The common iliac nodes, in turn, drain into the left and right lateral aortic nodal chains, which are part of the lumbar nodes.

The medial iliac lymph nodes in dogs serve as a significant drainage point in the lymphatic system.

They primarily receive lymph from various areas such as the superior parts of the middle to anterior pelvic organs, inferior pelvic viscera, deep perineum, and the gluteal region.

See also: Can Dogs Live Without Lymph Nodes?

Can Medial Iliac Lymph Nodes Be Removed?

Yes, medial iliac lymph nodes can be removed in dogs. This procedure is known as a pelvic lymphadenectomy and is often performed when there is a suspicion or confirmation of cancerous cells within the lymph nodes.

It’s an important part of cancer staging and treatment. The removal of these nodes can help in preventing the spread of cancer to other parts of the body.

However, this surgical procedure is not without risks. The most common complications after pelvic lymph node dissection are lymphocele formation, thromboembolic events, vascular injury, nerve injury, and ureteral injury.

See also: How Big Are Dog Lymph Nodes?

Causes of Enlarged Medial Iliac Lymph Nodes In Dogs

• Infection: Swollen lymph nodes usually indicate an infection from bacteria or viruses. Infections in areas of the lower body can specifically cause enlargement of medial iliac lymph nodes.
• Mange: Demodectic mange is a parasitic disease caused by mites, which can cause lymph node enlargement.
• Puppy “strangles” or juvenile cellulitis: This is a rare inflammatory condition that can cause swollen lymph nodes.
• Tick-borne diseases: Diseases such as Lyme disease transmitted by ticks can cause enlarged lymph nodes.
• Cancer: Malignant tumors can cause the enlargement of lymph nodes. Medial iliac lymph nodes are connected to each other by efferent lymph vessels, and cancer cells shed from a malignant tumor on one side could spread to the other.
• Autoimmune diseases: Some autoimmune diseases can also cause lymph node enlargement.
• Lymphoma: Not all dogs with enlarged lymph nodes have lymphoma, but this is one possible cause. Other symptoms and tests are needed for diagnosis.

Symptoms of Enlarged Medial Iliac Lymph Nodes In Dogs

• Nausea or lack of appetite: Dogs with enlarged medial iliac nodes may lose their appetite, which can lead to weight loss.
• Vomiting: This is another common symptom that can occur due to the body’s response to an underlying condition causing lymph node enlargement.
• Difficulty swallowing, eating, or breathing: If the lymph nodes in the jaw area are very swollen, it can affect a dog’s ability to eat and breathe comfortably.
• General discomfort or lethargy: Dogs with this condition may seem less active or more tired than usual. They may also show signs of discomfort such as restlessness or whimpering.
• Swelling or lumps: One or multiple lymph nodes can become swollen. If you notice a lump or swelling, especially in the lower abdominal area or near the hind legs, it could be due to enlarged medial iliac lymph nodes.
• Runny nose or extra eye discharge: These symptoms can sometimes be observed and may indicate an underlying infection or disease causing the lymph node enlargement.

Diagnosis of Enlarged Medial Iliac Lymph Nodes In Dogs

Diagnosing enlarged medial iliac lymph nodes in dogs includes:

Identification and Location

The medial iliac lymph nodes in dogs are the largest lymph nodes in the iliosacral lymph center. They are located laterally to the aorta near its trifurcation, between the deep circumflex iliac and the external iliac arteries.

If a medial iliac lymph node is located just cranial to the deep circumflex iliac artery, it may be difficult to distinguish from a lumbar aortic lymph node.

Drainage System

The Medial Iliac Lymph Nodes are parietal nodes and drain the colon, rectum, reproductive organs, urinary bladder, and urethra. This makes them a critical component of the canine lymphatic system.

Sonographic Evaluation

Ultrasonography is a non-invasive and reliable method for evaluating the medial iliac nodes in dogs.

These nodes are easy to identify during an ultrasound examination of the abdomen. Surrounding anatomy, knobology, and probing techniques are essential elements to accurately image these lymph nodes.

Inflammation and Enlargement

Enlargement of the medial iliac lymph nodes can be diagnosed through thoracic and abdominal X-rays or ultrasound. This condition, known as lymphadenopathy, often indicates an underlying health issue such as infection, autoimmune disease, or cancer.

For instance, immune-mediated diseases such as lupus, immune-mediated hemolytic anemia (IMHA), and polyarthritis can cause lymphadenopathy. Lymphoma, a cancer of the lymphatic system, is also a common cause of swollen lymph nodes in dogs.

Treatment of Enlarged Medial Iliac Lymph Nodes In Dogs

Treatment of enlarged medial iliac lymph nodes in dogs includes:

Medication Treatment

Various medications including steroids, anti-inflammatories, antibiotics, and anti-parasitics can be used to treat the condition causing the enlargement of the medial iliac lymph nodes.

The type of medication prescribed will depend on the underlying cause of the lymph node enlargement. For instance, if an infection is causing swelling, antibiotics may be used.

Surgical Intervention

In some cases, surgical intervention might be necessary. This is especially true if the enlargement is caused by malignant tumors. Bilateral medial iliac lymph node excision can be performed as a method of excisional biopsy for histopathologic diagnosis.

Chemotherapy

If the swollen lymph nodes are due to cancer such as lymphoma, more aggressive treatment options such as chemotherapy or radiation therapy may be recommended. Lymphoma is usually treated with chemotherapy, which consists of a series of injections given every week.

Follow-up Procedures

After treatment, follow-up procedures like fine needle aspiration or biopsies of abnormal canine medial iliac lymph nodes might still be needed to reach a definitive diagnosis and check the progress of the treatment.

FAQs

Q: What are medial iliac lymph nodes?

A: Medial iliac lymph nodes are a group of nodes located in the pelvic region of dogs. They are part of the abdominal lymph node chain.

Q: What is the function of medial iliac lymph nodes?

A: Medial iliac nodes play a crucial role in the immune system of dogs. They filter and trap foreign particles, including bacteria, viruses, and abnormal cells, to prevent them from spreading throughout the body.

Q: How are medial iliac lymph nodes related to abdominal lymph nodes?

A: Medial iliac lymph nodes are a subset of the abdominal lymph node chain. They are located in the pelvic area and contribute to the overall function of the abdominal lymphatic system.

Q: What is lymphadenopathy?

A: Lymphadenopathy refers to the abnormal enlargement of lymph nodes. It can occur in the medial iliac lymph nodes as well as other lymph nodes in the body. Lymphadenopathy is often a sign of an underlying health issue.

Q: How are medial iliac lymph nodes evaluated in veterinary practice?

A: Medial iliac lymph nodes are commonly evaluated using ultrasound examination in veterinary medicine. This non-invasive imaging technique allows veterinarians to detect any abnormalities or changes in the size or texture of the lymph nodes.

Q: Can ultrasonography detect abnormalities in medial iliac lymph nodes?

A: Yes, ultrasonography is an effective tool for detecting abnormalities in medial iliac lymph nodes. It allows for detailed imaging of the lymph nodes, helping to identify any signs of inflammation, enlargement, or metastasis.

Q: When should a biopsy of the medial iliac lymph nodes be considered?

A: A biopsy of the medial iliac lymph nodes may be considered when there are abnormal findings on ultrasound examination or when there is a suspicion of neoplasia (cancer). The biopsy helps in diagnosing the underlying cause and determining the appropriate treatment.

Q: Are there any other lymph nodes associated with the medial iliac lymph nodes?

A: Yes, the medial iliac lymph nodes are part of a larger network of lymph nodes in the pelvic region. These include the external iliac, internal iliac, deep circumflex iliac, and iliosacral lymph nodes.

Q: What are the normal size and appearance of medial iliac lymph nodes in dogs?

A: The normal size of medial iliac nodes in healthy dogs can vary, but they are typically smaller than some other abdominal lymph nodes. Ultrasonographic evaluation helps determine if the size and appearance are within normal limits.

Q: Are medial iliac lymph nodes more commonly affected by neoplasia or lymphoma in dogs?

A: Medial iliac nodes can be affected by neoplasia, including lymphoma, in dogs. However, the occurrence of neoplasia can vary depending on the individual case. Further diagnostic tests are necessary for a definitive diagnosis.

In Conclusion

In conclusion, medial iliac nodes in dogs can be caused by a variety of conditions and may cause a range of symptoms.

It is important for pet owners to seek veterinary care if they suspect their dog has swollen lymph nodes, as this could indicate a more serious condition.