Page 251 - Concise Pathology for Exam Preparation ( PDFDrive )

236 SECTION II Diseases of Organ Systems

Microscopy

• Early stage: Polymorphs in all the layers of vessels accompanied by thrombosis in the
lumen
• Advanced stage: Mononuclear infiltrate with fibrosis
Q. Describe the salient features of phlebothrombosis
(thrombophlebitis).
Ans. Salient features of phlebothrombosis
• Deep leg veins are involved in more than 90% cases followed by periprostatic venous
plexus in males and pelvic venous plexus in females.
• Cardiac failure, genetic hypercoagulability syndromes, neoplasia, pregnancy, obesity,
post-operative state, prolonged bed rest and immobilization are the most important
clinical predispositions.
• Migratory thrombophlebitis (Trousseau sign) is seen in adenocarcinomas of pancreas,
colon and lung. Hypercoagulability may occur as part of a paraneoplastic syndrome.
The resultant venous thrombosis has a tendency to appear in one site only to disappear,
followed by thromboses in other veins (migration).
• Thrombi in the legs present with:
• Local manifestations
• Oedema distal to an occluded vein
• Cyanosis
• Dilatation of superficial veins
• Heat, tenderness, redness, swelling and pain
Note: Above features may be absent in bedridden patients. In these patients, pain
is elicited by applying pressure over affected veins, squeezing the calf muscles,
or forced dorsiflexion of foot (Homans sign).
• Pulmonary embolism
• Common and serious manifestation (not infrequently may be the first manifesta-
tion). It is due to the contraction of the surrounding vessels, which tends to
displace the thrombi from their attachment.

Q. Write briefly about superior vena caval syndrome.

Ans. It is usually caused by a neoplasm that compresses and invades superior vena cava,
most commonly bronchogenic carcinoma and mediastinal lymphoma. Manifests as dusky
cyanosis, dilatation of veins of head, neck and arms. Pulmonary vessels may also get
compressed causing respiratory distress.

Q. Write briefly about inferior vena caval syndrome.
Ans. Many neoplasms, eg, hepatocellular and renal cell carcinoma, show a striking
tendency to grow within veins with ultimate extension into IVC (occasionally into
right atrium). It manifests with marked oedema of legs, distension of superficial
collateral veins of lower abdomen and massive proteinuria (due to renal vein
involvement).
Q. Write briefly about lymphangitis and lymphoedema.

Ans. Primary lymphangitis is an extremely uncommon primary disorder of the lym-
phatic vessels. Secondary lymphangitis and lymphoedema develop in association with
inflammation and cancer. Lymphangitis may be acute or chronic depending on
its duration.
• Acute lymphangitis is caused by bacterial infections, most commonly b-haemolytic
streptococci (Flowchart 10.3).
• Chronic lymphangitis: Results from persistence of acute lymphangitis or chronic infec-
tions, eg, tuberculosis, syphilis and actinomycosis.

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