Lymph Node Examination and Organomegaly — Short Answer Question

SAQ 1 — The Lymph Node and Organomegaly Short Case (20 marks, 30 minutes)

Model Answer

(a) The systematic head-to-toe lymph node routine (3 marks): [1]

The lymph node examination is performed in a fixed, reproducible order so that no region is omitted: head and neck, then axillary, then epitrochlear, then inguinal, then popliteal. The head and neck nodes are palpated in the following order, using the pads of the index and middle fingers with the patient's neck slightly flexed: submental, submandibular, pre-auricular, post-auricular, occipital, tonsillar (jugulodigastric), anterior cervical chain, posterior cervical chain, supraclavicular, and pre-tracheal. The supraclavicular fossae are palpated from behind the patient, with the neck flexed forward and the shoulders relaxed, placing the fingers deep into the angle between the clavicle and the sternocleidomastoid. The axillary nodes are examined as five groups — apical, anterior (pectoral), posterior (subscapular), lateral (humeral), and central — by supporting the patient's arm and placing the examining hand high into the axillary apex. The epitrochlear node is palpated above and 3 cm proximal to the medial epicondyle, between biceps and triceps, with the elbow flexed. The inguinal nodes are examined as horizontal (along the inguinal ligament) and vertical (along the saphenous vein) groups. The popliteal node is palpated deeply in the popliteal fossa. [1]

(b) The five characteristics of a node and the interpretation of consistency (4 marks): [1]

Every palpable node is described by five characteristics: (1) Site — the anatomical group precisely named, and the distribution (localised versus generalised); (2) Size — measured in centimetres, with nodes over 1 cm generally abnormal (inguinal up to 1 to 2 cm may be normal); (3) Consistency — the single most discriminating feature; (4) Mobility and matting — mobile, matted, or fixed to skin or deep structures; (5) Tenderness and the overlying skin — tender (infection) versus non-tender (chronic or malignant), with examination for erythema, sinus tract, and ulceration. [1]

The consistency is interpreted as follows: soft (like a lip) is reactive or infective; firm (like the tip of the nose) is lymphoma (non-Hodgkin), chronic lymphocytic leukaemia, or granulomatous disease; rubbery (like india rubber) is the classic consistency of Hodgkin lymphoma, reflecting the orderly proliferation of Reed-Sternberg cells within reactive inflammatory cells; hard (like bone) is metastatic carcinoma; matted (nodes fused into a confluent mass) is tuberculosis (caseating nodes) or advanced lymphoma [4].

(c) The mechanism and significance of a Virchow node (3 marks): [1]

A Virchow node (Troisier sign) is a hard, enlarged LEFT supraclavicular node. The mechanism is lymphatic drainage: the thoracic duct drains lymph from the entire abdomen (via the cisterna chyli) and empties into the left venous angle — the junction of the left subclavian vein and the left internal jugular vein. Malignant cells from the abdomen are trapped at this lymphatic bottleneck. The classic primary is gastric cancer, but pancreatic, hepatobiliary, colorectal, testicular, ovarian, and renal malignancy also metastasise here. A right supraclavicular node receives lymph from the right hemithorax (via the right lymphatic duct) and more often signals lung cancer or a mediastinal lymphoma. A Virchow node of any size mandates urgent upper GI endoscopy and cross-sectional imaging. Supraclavicular lymphadenopathy is identified as the location most worrisome for malignancy in both the Ferrer and the Habermann and Steensma reviews [3][4].

(d) Technique for the spleen and the three spleen-versus-kidney discriminators (4 marks): [1]

The spleen is examined from the RIGHT side of the patient. The right hand starts flat in the right iliac fossa, lateral to the rectus, with the fingers pointing diagonally toward the left costal margin along the line of the tenth rib (the long axis of the spleen). The left hand splints the lower left ribs from behind to lift the spleen forward. The patient breathes in slowly and deeply; as the diaphragm descends, the splenic edge moves downward and medially along the diagonal axis and taps the fingertips. The hand moves one to two centimetres toward the costal margin with each inspiration. The right lateral decubitus position improves sensitivity for a just-palpable spleen. [1]

The three bedside discriminators between a spleen and an enlarged left kidney are: (1) You cannot get above the spleen — its upper border is continuous with the diaphragm; you can palpate above a ballotable kidney because it descends from the retroperitoneum. (2) The spleen is dull to percussion (it lies behind the stomach as a solid organ); the kidney is resonant (the stomach and splenic flexure containing gas overlie it). (3) The spleen has a notch on its medial border; the kidney has no notch. Additionally, the spleen moves with respiration and cannot be ballotted, while the kidney enlarges downward and can be ballotted. The Grover systematic review found these manoeuvres have moderate sensitivity and that a non-palpable spleen does not exclude splenomegaly [1].

(e) Grading of splenomegaly and the causes of massive splenomegaly (3 marks): [1]

Splenomegaly is graded as: mild (just palpable, a few centimetres below the costal margin) — causes include portal hypertension, acute and chronic infection, haemolytic anaemia, and congestive states; moderate (to the umbilicus) — adds lymphoma, chronic leukaemias, myelofibrosis, thalassaemia, and chronic infection; and massive (beyond the umbilicus into the right iliac fossa, crossing the midline). [1]

The causes of MASSIVE splenomegaly are a short, high-yield list: chronic myeloid leukaemia (CML), myelofibrosis, chronic malaria (hyperreactive malarial splenomegaly), visceral leishmaniasis (kala-azar), Gaucher disease, and primary hypersplenism. The combination of massive splenomegaly with pallor points to a myeloproliferative neoplasm (CML or myelofibrosis); a travel history points to malaria or kala-azar; and a patient of Ashkenazi Jewish ancestry with pancytopenia and bone pain raises Gaucher disease [1].

(f) A palpable liver edge does not always mean hepatomegaly (3 marks): [1]

A palpable liver edge may reflect downward DISPLACEMENT of a normal-sized liver rather than true enlargement. The liver is displaced downward by a depressed diaphragm in chronic obstructive pulmonary disease, asthma, or a large right pleural effusion. A Riedel lobe is a normal anatomical variant — a tongue of liver tissue projecting from the right lobe — that is palpable without hepatomegaly. [1]

The resolution is to measure the liver span by percussion: percuss downward from the right third intercostal space in the midclavicular line until the note changes from resonant (lung) to dull (the upper liver border), and percuss upward from below the costal margin until the note changes from tympanic (bowel) to dull (the lower border). The distance between the two is the liver span; a normal span is 12 to 15 cm. In COPD, the span is normal and the edge is displaced. The Naylor systematic review found that the percussion span is the more reliable bedside measure than the palpable edge alone, which has significant interobserver variability [2].