TOC  | D-Dx    

Lymphadenopathy

LOCALIZED LYMPHADENOPATHY  

Submandibular or Cervical (unilateral) lymphadenopathy
which is perhaps the most common type of adenopathy, frequently results from pharyngitis (viral, streptococcal, gonococcal) or oral, head and neck or intraoral infection or malignancy.

Cervical Bilateral: Mononucleosis , Sarcoidosis , Toxoplasmosis , Pharyngitis

Anterior cervical lymphadenopathy often results from head and neck infections

Anterior Auricular :Viral conjunctivitis ,Trachoma, posterior auricular , Rubella , Scalp infection

Preauricular adenopathy may be a component of "occuloglandular fevers" resulting from adenoviral conjunctivitis, sarcoidosis, tularemia, cat-scratch disease, and other processes.

Posterior auricular or posterior cervical adenopathy frequently reflects infections of the scalp but may also be prominent in systemic processes, such as rubella or toxoplasmosis.

Isolated supraclavicular node enlargement is more indicative of metastatic malignancy

Supraclavicular, Right :
Pulmonary malignancy, Mediastinal malignancy , Esophageal malignancy

Supraclavicular, Left: Intrabdominal malignancy , Renal malignancy , Testicular or ovarian malignancy

Axillary: Breast malignancy or infection , Upper extremity infection

Epitrochlear: Syphilis (bilateral), Hand infection (unilateral) , & many other systemic processes.

Inguinal: Syphilis, Genital herpes, Lymphogranuloma venereum, Chancroid, Lower extremity or local infection
Inguinal nodes are palpable in most normal individuals, but they can enlarge substantially in infections of the genitalia or perineum, and in infections of the lower extremities.

Bilateral hilar adenopathy
encountered as an incidental finding on a chest radiograph in an otherwise asymptomatic patient is likely to be caused by sarcoidosis. In about 80% of such cases, the adenopathy will resolve spontaneously. In areas endemic for fungal infection, asymptomatic bilateral hilar adenopathy may result from coccidiomycosis or histoplasmosis. Lymphoma and bronchogenic carcinoma can cause bilateral hilar adenopathy, but the patient is rarely asymptomatic at the time of presentation. The same pertains, although to a lesser degree, to primary tuberculosis.

Hilar Adenopathy, Unilateral

Any Region :

GENERALIZED LYMPHADENOPATHY  
Generalized adenopathy, particularly if accompanied by weight loss, fever, or other constitutional symptoms, should raise the question of AIDS or HIV infection. Male homosexuals, IV drug abusers, hemophiliacs and other multiply transfused individuals, and Haitians are at particular risk .

REF: Goroll: Primary Care Medicine, 4th ed., 2000 - HARVEY B. SIMON

Of the nearly 600 lymph nodes throughout the body, only a few are normally palpable, including small nodes in the submandibular, axillary, and inguinal regions. Nevertheless, lymphadenopathy is a very common presenting symptom. Most often, adenopathy indicates benign, self-limited disease; this is particularly true in children and young adults, who are more prone to reactive lymphatic hyperplasia. Despite this, patient concern is often substantial because of worry about serious infectious processes (e.g., AIDS) on the one hand and neoplastic diseases on the other. A systematic evaluation of lymph-adenopathy will provide both reassurance and a correct diagnosis. A critical decision for the primary physician is when to refer the patient for a lymph node biopsy.

PATHOPHYSIOLOGY AND CLINICAL PRESENTATION

Small lymph nodes in the neck, axilla, and groin may be palpable in normal individuals. Palpable nodes in other regions or any node exceeding 1 cm in size should be regarded as potentially abnormal. Inflammation and infiltration are responsible for pathologic enlargement. Although size alone is not itself diagnostic, nodes larger than 3 cm suggest neoplastic disease. Localized lymphadenopathy may represent spread of disease from an area of drainage. Of particular importance are palpable supraclavicular nodes. The left one, sometimes referred to as the " sentinel" node, is in contact with the thoracic duct, which drains much of the abdominal cavity. The right supraclavicular node drains the mediastinum, lungs, and esophagus.

Other Lymphatic Abnormalities.

Lymphangitis, appearing as red, warm streaks along the course of superficial lymphatic networks, suggests an acute inflammatory response to pyogenic infection in the drainage area; staphylococci and streptococci are frequently responsible. Lymph-adenitis, presenting as a tender, warm, soft, rapidly enlarging node, has a similar significance and often reflects acute pyogenic infection of the node itself. An idiopathic variant, necrotizing lymphadenitis ( Kikuchi' s disease), causes self-limited tender cervical adenopathy.

Lymphedema results from the interruption of lymphatic drainage; surgical node dissection, radiotherapy, or fibrosis caused by chronic infections such as filariasis or lympho-granuloma venereum are causes of lymphedema.

WORKUP

History and Physical Examination

A number of basic questions arise in the evaluation of lymph-adenopathy that can be readily addressed by a careful history and physical examination:

1.  Is the palpable mass indeed a lymph node?

2.  Is the lymphadenopathy acute or chronic?
Clearly, lymph node enlargement resulting from acute viral or pyogenic infection becomes less likely as the days and weeks pass, and granulomatous inflammation (sarcoidosis, tuberculosis, fungal infection) and neoplastic disease become greater worries. Even so, chronicity alone is not always a harbinger of serious disease, for on occasion reactive hyperplasia can persist for many months.

3.  What is the character of the enlarged node itself?
Tender, mobile nodes most often reflect lymphadenitis or lymphatic hyperplasia in response to acute inflammation.
Firm, rubbery, nontender nodes may be found in lymphoma.
Painless, stone-hard, fixed, matted nodes suggest metastatic carcinoma.

4.  Are there associated systemic or localizing symptoms or signs?
Fever, rash, weight loss, sore throat, dental pain, genital inflammation, and infections of the extremities are clues that may be particularly helpful. Of these symptoms, night sweats and weight loss are suggestive of granulomatous and neoplastic disease. Ear, nose, and throat symptoms suggest reactive lymphatic hyperplasia secondary to viral or localized bacterial infection.

A careful examination of the skin for a primary inoculation site may provide the clue to a diagnosis of cat-scratch disease or tularemia. A check for scalp infections, dermatophytes, and scabies is also needed. The liver and spleen are carefully examined; organomegaly may be an important clue for mononucleosis, sarcoidosis, or malignancy. Sternal tenderness may be present in leukemia.

5.  Are there unusual epidemiologic clues?
To cite a few examples, in patients exposed to cats, cat-scratch disease or toxoplasmosis, which can also result from eating poorly cooked meat, may develop. Travel to the southwestern United States may suggest the possibility of plague. An appropriate travel history or exposure to bird droppings may suggest fungal infection, as may lacerations sustained during gardening in the case of sporotrichosis. Contact with wild rodents can result in tularemia, as can tick bites. A history of exposure to tuberculosis may be an important clue to scrofula. More commonly, community outbreaks can provide clues to the diagnosis of streptococcal pharyngitis or rubella, whereas a history of sexual exposure may raise the question of gonorrhea, syphilis, genital herpes, or lymphogranuloma.

Laboratory Studies

Laboratory studies need not be very elaborate. A complete blood cell count with differential often provides useful information and is almost always indicated. For example, atypical lymphocytosis suggests mononucleosis, other viral infections, and toxoplasmosis; granulocytosis is indicative of pyogenic infection; eosinophilia raises the question of a hypersensitivity reaction; pancytopenia is consistent with marrow suppression by tumor and HIV infection.

Other studies are based on the clinical presentation of the lymphadenopathy. A variety of blood chemistries may help in selected cases. Elevations of uric acid may reflect lymphoma or other hematologic malignancies. Serum liver chemistries (especially the alkaline phosphatase level) provide objective parameters to follow. Although such abnormalities are nonspecific, they do suggest liver involvement, which can be further evaluated by biopsy.

Lymph Node Biopsy should be considered as the most direct approach to the diagnosis of lymphadenopathy. Although the majority of such procedures are technically easy and can be accomplished under local anesthesia, this is an invasive test that can sometimes prove nondiagnostic. It should be employed only when simpler approaches have failed to give a diagnosis and suspicion of a therapeutically important cause remains (e.g., tuberculosis, lymphoma, cancer, sarcoidosis, cat-scratch disease). Sometimes, careful observation for a period of time may be diagnostically useful before biopsy is undertaken. In many cases of benign lymphadenopathy, the nodes will regress spontaneously even if no etiologic diagnosis has been made. However, some lymphomas may regress transiently and simulate a more benign etiology.