Complications of lymphadenitis

General clinical manifestations

Pathological processes in lymph nodes rarely proceed asymptomatically. Most commonly, the disease is accompanied by pronounced local pain and enlargement of the affected nodes. In addition to local manifestations, patients develop a systemic reaction to inflammation.

Key general symptoms include:

• Elevated body temperature of varying severity.
• Signs of intoxication: headache, generalized weakness, and a feeling of malaise.
• Concomitant involvement of lymphatic vessels (lymphangitis), which is often observed simultaneously with the primary disease.

Progression of the process: from serous to purulent inflammation

The clinical presentation and risk of complications directly depend on the stage and form of the inflammatory process. Differential diagnosis is based on local and general manifestations.

Serous (catarrhal) lymphadenitis At this stage, the patient's general well-being is minimally affected. Local symptoms are limited to a dull ache in the area of regional nodes. Upon palpation, the nodes are felt as firm, enlarged, and painful. An important diagnostic criterion: the lymph nodes remain mobile, they are not fused to underlying tissues, and the skin over them retains its normal color and structure.

Purulent lymphadenitis Disease progression leads to a sharp increase in pain. The skin over the focus becomes hyperemic, and any touch causes severe pain. Due to the breakdown of the capsule, the nodes fuse both with each other and with surrounding structures, turning into a single, completely immobile conglomerate.

Severe forms and direct complications

If the purulent process cannot be controlled, it extends beyond the lymphatic system, affecting the surrounding adipose tissue. This leads to the development of severe complications.

1. Adenophlegmon

Characterized by the formation of a dense infiltrate that lacks clear borders. The skin over it acquires diffuse hyperemia. The patient's general condition sharply deteriorates and is assessed as severe. Pronounced weakness, tachycardia, severe chills, and critically high body temperature are observed.

1. Putrid phlegmon

A specific form in which tissues undergo putrid degradation. A characteristic physical sign is crepitus—a specific crunching sound detected upon palpation of the lesion, which indicates gas accumulation in the tissues.

Systemic complications Further uncontrolled spread of infection leads to critical consequences:

• Rupture and spread of purulent masses into deep fascial spaces (including the mediastinum and retroperitoneal space).
• Development of a generalized infection—sepsis, which poses a direct threat to the patient's life.

Differential diagnosis in abdominal complications

In cases where the inflammatory process affects retroperitoneal lymph nodes or the mesentery, the clinical picture must be differentiated from inflammatory bowel disease (IBD), such as ulcerative colitis (Colitis ulcerosa) and Crohn's disease.

IBD is also characterized by systemic manifestations and changes in surrounding tissues detected by cross-sectional imaging (CT, MRI, ultrasound). For example, during a flare-up of Crohn's disease, inflammation is transmural, and the adipose tissue around the bowel becomes echogenic. Unlike lymphadenitis, where adenophlegmons form, IBD can lead to mesenteric phlegmons, low-density intra-abdominal abscesses (10–30 HU) with gas bubbles, as well as deep fissuring ulcers leading to fistulae.

Endoscopic and radiological findings in concomitant colitis

If bowel inflammation is suspected as the primary source of infection, specialized diagnostic methods are applied.

• Radiological diagnostics: The main sign of colitis is bowel wall thickening up to 4 mm or more. A layered contrast enhancement pattern is characteristic. CT visualizes extramural changes, including lymphadenopathy and mesenteric edema.
• Ulcerative colitis: The lesion always starts in the rectum and spreads proximally. Inflammation is limited to the mucosa. Due to extensive ulceration, islands of preserved tissue can form — pseudopolyipoid elevations (pseudopolyps), and during the healing stage, post-inflammatory polyps.
• Crohn's disease: Characterized by asymmetric involvement. Aphthous ulcers on the mucosa are typical. In advanced cases, the layering of the bowel wall is lost (differentiation between submucosa and muscularis propria), which is clearly visible on high-resolution ultrasound.

Class and exam questions

What else to study on this topic

• Pathogenesis of the transition from catarrhal to purulent inflammation
• Anatomy of fascial spaces of the mediastinum and retroperitoneal region
• Montreal classification of Crohn's disease
• Radiological contrast enhancement patterns in inflammatory bowel diseases
• Histological picture of pseudopolyps

Other topics in the "Additional Topics" section

Prepared by WhiteCoat Pro faculty in accordance with the medical school curriculum. For educational purposes only.