LENFADENOPATHY

DEFINITION abnormality of the lymph nodes in terms of number, hardness, and volume

LAP Generalized LAP: two or more seperate lymph node group are effected. Localized LAP: one or more lymph nodes in the same region are effected

Epidemiology Rece is not a major criteria. Sex: M/F=1 Age: most frequent in younger children, less frequent in newborn.

Pathophsiology Increase in the number of benign lymphocytes and macrophages in the process of response to antigens Infiltration of the lymph nodes with the inflammatory cells during infection Infiltration of the lymph nodes with metastatic malignant cells In situ proliferation of lymphocytes and macrophages Infiltration of the lymph nodes with metabolite-laden macrophages during storage diseases

I. Generalized Lenfadenopahy A- Infection B- Neoplastic ve proliferative disorders C- Storage diseases D- Autoimmune disorders and hypersensitivity reactions

A- Infections 1- Viral: - Generalized upper respiratort tract infections - Infectious mononucleosis - CMV - AIDS - chickenpox - measles

A- Infections 2-Bacterial - Septisemia - Typhoid fever - Tb - Syphilis

A- Infections 3- Protozoal - Toxoplazmosis 4- Fungal - Coccidiomycosis

B- Neoplastic and Proliferative Disorders Acute leukemia Lymphomas (Hodgkin, non-Hodgkin) Neuroblastoma Histiocytosis

C- Storage diseases Gaucher Niemann-Pick

D- Otoimmune disorders and Hypersensitivity reactions Juvenile rhomatoid arthritis (JRA) Systemic lupus erythematosus Drug reactions (eg: fenitoin, allopurinol) Serum sickness

2- Localized lymphadenopathy Cervical Submaxillary and submental Occipital Preauricular Mediastinal Supraclavicular Axillary Abdominal Inguinal

Cervical Viral URTI IM Rubella Cat scratch disease Streptococcal pharyngitis Acute bacterial lymphadenitis Toxoplasmosis Tb/atypical mycobacterial infection Acute leukemia Lymphoma Neuroblastoma Rhabdomyosarcoma Kawasaki disease Nasopharynx carcinoma

Submaxillary and submental Oral and dental infections Acute lymphadenitis

Occipital Pediculosis capitis Tinea capitis Secondary to local skin infections Rubella

Preauricular Local skin infections chronic ophtalmic infections Cat-scratch disease

Mediastinal ALL Lymphoma Sarkoidosis Cystic fibrosis Tb Histoplasmosis Coccidiomycosis

Supraclavicular Lymphoma Tb Histoplasmosis Coccidiomycosis

Abdominal Acute mesenteric adenitis Lymphoma

Inguinal Local infection Diaper dermatitis Insect bite Syphilis Lenfogranuloma venerum

Approach to a patient with LAP

criteria for LAP differs in pediatric age group. small, hard, a few mm in diameter bilateral ant. cervical Axillary Inguinal Occipital Normal < 2 cm. < 1 cm. < 1.5 cm.

LAP in newborn is always abnormal Lymph nodes >10 mm are considered enlarged Epitrochlear Inguinal Posterior auricular, epitrochlear and supraclavicular Abnormal even 5 mm. > 15 mm.

History and PE History: Duration Accompanying condition: eg: contact with cats,rodent bite, tick bite, tonsillitis, skin lesions etc… Symptoms (fever, weight loss, night sweats) Medications: fenitoin, cephalosporins,sulphonamids… Travel history

Physical examination: Localization: tonsillar and inguinal lymph nodes: secondary to localized infections Supraclavicular (SC) and axillary lymph nodes (even if<0.5 cm. ) warrant further investigation left SC: intraabdominal malignancy right SC: thoracic malignancy

size: character: Symptoms: hard,rubbery ones without tenderness and redness suggest malignancy. Occasionally rapid growing malignant lymph node may be tender Warm, tender and fluctuant lymph nodes suggest infection or inflammation (lymphadenitis) Symptoms: Localized pain tenderness redness

Dysphagia and respiratory difficulty occur as a result of abscess formation of the retropharyngeal nodes. cyanosis, dyspnea, stridor, cough, fascial edema suggest mediastinal LAP Abdominal pain suggests mesenteric and retroperitoneal LAP

Work-up for localized or generalized LAP Thorough history of infection, contact with rodents or cats and systemic complaints Physical examination for evidence of hematologic disease, such as hepatosplenomegaly and petechiae) Blood count and, ESR Skin tests (Tb, Cat scratch disease, fungal infections) Cultures (from the regional lesions  throat etc. Serologic tests (Toxoplazmozis, CMV,EBV,HIV..etc)

Chest radiograph and CT scan (if necessary); abdominal sonogram and CT, if indicated Ultrasonography is useful in an acute setting in assessing whether a swelling is nodal in origin, an infected cyst or other soft tissue mass. It may detect an abscess requiring drainage Lymph node aspiration and culture; helpful in isolating the causative organism and deciding on an appropriate antibiotic when infection is the cause of the lymphadenopathy Fine needle aspiration; may yield a definite or preliminary cytologic diagnosis andoccasionally obviate the need for lymph node biopsy; it provides limited material in the event flow cytometry is required and negative results cannot rule out a malignancy because the sample may be inadequate Bone marrow examination if leukemia or lymphoma is suspected Lymph node biopsy

Indications for lymph node biopsy Lymph node biopsy is indicated if: • Initial physical examination and history suggest malignancy • Lymph node size is greater than 2.5 cm in absence of signs of infection • Lymph node persists or enlarges • Appropriate antibiotics fail to shrink node within 2 weeks • Supraclavicular adenopathy.

Following precautions should be observed during Bx Upper cervical and inguinal areas should be avoided; lower cervical and axillary nodes are more likely to give reliable information The largest node should be biopsied, not the most accessible one. The oncologist should select the node to be biopsied in consultation with the surgeon The node should be removed intact with the capsule, not piecemeal The lymph node should be immediately submitted to the pathologist fresh or in sufficient tissue culture medium. The node must not be left in strong light it should not be wrapped in dry gauze. Fresh and frozen samples should be set aside for additional studies

What to do with the biopsy 1-culture: bacterial,viral,fungal and gram staining 2-viral studies 3-histologic examination 4-light and electron microscopy 5-immunohystochemical staning: in order to differenciate the tumor type 6-flow cytometry: to decide upon the type of leukemia or lymphoma 7-genetic investigations