Causes of enlarged lymph nodes

An increase in the lymph nodes of one group is called local (regional) lymphadenopathy, an increase in the lymph nodes of two or more groups is called polyadenopathy or generalized lymphadenopathy.

A distinction is made between acute (up to 3 months), protracted (up to 6 months) and chronic (persistent) lymphadenopathy (over 6 months).

In infectious diseases, lymphadenitis develops more often - inflammation of the lymph nodes, usually closest to the site of penetration of the pathogen; the nature of the inflammatory process in the lymph nodes may be different (serous, serous-hemorrhagic, purulent inflammation). Lymphadenitis may be combined with primary affect or polyadenopathy (with tularemia, plague, listeriosis, syphilis, benign lymphoreticulosis, measles, rubella, toxoplasmosis).

Lymphadenitis is characteristic of tularemia, plague, yersiniosis, anthrax, scarlet fever, erysipelas, tonsillitis, listeriosis, staphylococcal and streptococcal purulent infection, diphtheria, tick-borne borreliosis, sodoku, tick-borne North Asian typhus, herpes infection, foot-and-mouth disease, cowpox.

Acute and (less often) chronic lymphadenitis may be accompanied by suppuration and necrosis of the affected lymph nodes (purulent streptococcal and staphylococcal infection, scarlet fever, tonsillitis, benign lymphoreticulosis, plague, tularemia). The outcome may be complete resorption of the lymph nodes or their sclerosis.

Often, the inflammatory process in the lymph nodes is specific. In this case, histological examination of the biopsy or postmortem examination allows us to detect specific granulomas (brucellosis, benign lymphoreticulosis, pseudotuberculosis, listeriosis, tularemia, tuberculosis, syphilis, etc.).

Tularemia (its bubonic forms, including ulcerative-bubonic, ocular-bubonic, anginal-bubonic) is one of the most demonstrative representatives of the group of diseases with local lymphadenopathy. The bubo, most often inguinal, axillary, cervical, usually forms in the lymph nodes closest to the site of penetration of the pathogen, and is combined with a general infectious syndrome - fever, moderate intoxication, as well as with local changes (primary affect) - a small painless ulcer on the skin at the site of an insect bite, or unilateral conjunctivitis, or tonsillitis (unilateral, ulcerative-necrotic or membranous). The size of a tularemia bubo is 3-5 cm in diameter, but can be larger (up to 10 cm); it is characterized by clear contours, absence of periadenitis, mobility, slight pain on palpation. The skin above the bubo is initially unchanged, but in the absence of adequate antibiotic therapy, after 3-4 weeks, suppuration of the bubo is possible (then the skin turns red, the lymph node fuses with it, becomes painful, fluctuation appears), its spontaneous opening with the formation of a fistula. With sclerosis of the bubo, the enlargement of the lymph nodes persists for a long time after recovery. One of the options for the evolution of the bubo is resorption, which occurs slowly, over several months.

Benign lymphoreticulosis (cat scratch disease, felinosis) can cause lymphadenitis, especially in children and adolescents. The diagnosis is based on the epidemiological history (contact with cats, their scratches and bites), detection of a papule-vesicle-pustule at the site of the primary scratch, an increase in the diameter of the regional lymph node to 2.5-4.0 cm or more, and an increase in body temperature. The lymph nodes are of a dense elastic consistency, slightly mobile due to periadenitis, moderately painful on palpation, the skin above them is hyperemic, and the surrounding tissues are edematous. Lymphatic adenitis may develop not only in the regional (e.g., elbow) lymph node, but also in those following it along the lymph flow (e.g., axillary); sometimes not one, but several lymph nodes of one or neighboring groups are enlarged. After 2-4 weeks, the lymph nodes may become suppurated, fistulas are formed and pus is released. The process tends to be protracted and recurrent, fever, intoxication, lymphadenitis may persist for several months.

Rat bite disease (sodoku). At the site of the bite, swelling, hyperemia of the skin, soreness and enlargement of the regional or group of lymph nodes appear, which are dense to the touch, fused together and with the surrounding tissues. From the bite area, where ulcers and foci of necrosis can form, to the enlarged lymph nodes, an edematous red stripe is noticeable - lymphangitis. In the biopsy of the enlarged lymph node, hyperplasia of the lymphoid tissue and small-cell infiltration are found. The pathogen can be isolated by sowing a puncture of the lymph nodes.

In practice, it is often necessary to conduct differential diagnostics between purulent "banal" lymphadenitis and specific lymphadenitis in tularemia, as well as in plague. It should be taken into account that nonspecific purulent lymphadenitis is often secondary, and the primary purulent focus can be furuncles, an infected wound, an abscess, a panaritium, mastitis, etc. Lymphangitis is often detected from the primary focus to the regional lymph node, which is usually significantly enlarged, painful, the skin above it is hyperemic. Fever, intoxication occur simultaneously with lymphadenitis or later, and do not precede it. Neutrophilic leukocytosis, increased ESR are determined in the hemogram. When sowing pus obtained during puncture of the lymph node, streptococcus or staphylococcus is isolated.

Comparative characteristics of purulent lymphadenitis and bubo in plague, tularemia

Sign	Plague	Tularemia	Purulent lymphadenitis
Painfulness	Sharp	Minor	Expressed
Periadenitis	Eat	No	Possible
Contours	Fuzzy	Clear	With periadenitis, the lines are unclear.
Skin over the bubo	Crimson red	Unchanged, cyanotic when suppurating	Red
Suppuration and autopsy	As a rule, on the 8th-10th day of illness	Intermittently, every 3-4 weeks	Maybe in the first days
Primary affect	Rarely in cutaneous form	Often	Purulent focus (furuncle, panaritium, etc.)
Intoxication	Sharply expressed	Moderate	Weak
Fever	Precedes the bubo	Precedes the bubo	Appears simultaneously with or after local changes

In infectious mononucleosis caused by EBV, there is a symmetrical enlargement of primarily the posterior cervical and submandibular lymph nodes, to a lesser extent and less often - axillary and inguinal. Usually, the lymph nodes enlarge in groups, less often - one at a time, their size can vary from 0.5 to 5 cm. On palpation, the lymph nodes are dense, not fused with each other and with the surrounding tissue, painless or slightly painful, the color of the skin above them is not changed. Sometimes pastosity of the subcutaneous tissue is visible around the enlarged lymph nodes on the neck. Infectious mononucleosis is characterized by a discrepancy between the degree of enlargement of the lymph nodes and the severity of changes in the oropharynx: the tonsils can be significantly enlarged, edematous, covered with a continuous dense plaque that extends beyond their boundaries. The size of the lymph nodes in this case is slightly larger than usual. Conversely, tonsillitis can be catarrhal, and the cervical lymph nodes reach large sizes, sometimes forming a solid conglomerate. As a rule, the cervical lymph nodes in infectious mononucleosis are clearly contoured and are clearly visible when turning the head. In some patients, lymphadenopathy reaches such a degree that the configuration of the neck changes - the so-called bull neck. There is no suppuration of the lymph nodes in infectious mononucleosis.

Lymphadenopathy is one of the clinical manifestations of HIV infection. In the acute stage of HIV infection, the occipital and posterior cervical lymph nodes usually enlarge, later - the submandibular, axillary and inguinal. The lymph nodes are painless, soft-elastic consistency, 1-3 cm in diameter, not fused with each other or with the surrounding tissues, the skin above them is not changed. Simultaneously with lymphadenopathy, fever is observed, often pharyngitis and / or tonsillitis, liver enlargement, and sometimes spleen. The described symptom complex is extremely similar to infectious mononucleosis and is therefore called "mononucleosis-like syndrome". The duration of polyadenopathy that occurs in the acute stage of HIV infection is most often 2-4 weeks. As the disease progresses, lymphadenopathy persists or appears for the first time, and subsequently, over the course of several months/years, generalized lymphadenopathy may be the only clinical marker of HIV infection or be combined with its other manifestations.

The addition of opportunistic infections is accompanied by compaction of the lymph nodes, their consistency becomes densely elastic, the localization and size of the lymph nodes depend on specific secondary diseases. In the terminal stage of HIV infection, the size of the lymph nodes noticeably decreases, some previously enlarged ones cease to be palpated at all. Thus, both the size and consistency of the lymph nodes, as well as the duration and localization of lymphadenopathy, can be very diverse in HIV infection, which necessitates laboratory testing for HIV infection of all patients with lymphadenopathy of unknown etiology.

Rubella is one of the most significant infections characterized by peripheral lymphadenopathy. Already in the prodromal period, even before the appearance of any other clinical symptoms, the occipital, postauricular and posterior cervical lymph nodes enlarge, while they become dense and painful upon palpation. Enlarged lymph nodes are a pathognomonic symptom of rubella, it can be so pronounced that it can be determined visually.

With measles, the same groups of lymph nodes enlarge as with rubella, but they are painless on palpation. Lymph node adenopathy is not the leading symptom of measles, it is combined with more vivid manifestations of this disease, including pronounced catarrhal syndrome, Belsky-Filatov-Koplik spots on the oral mucosa, abundant maculopapular exanthema, appearing and disappearing in stages, leaving behind pigmentation.

[ 1 ], [ 2 ], [ 3 ], [ 4 ], [ 5 ], [ 6 ]