THE HAEMOPOIETIC SYSTEM

Abnormalities of the haemopoietic system may produce anaemia, polycythaemia, lymphadenopathy, hepatosplenomegaly, or purpura alone or in combination. Pallor is the outstanding physical sign of anaemia and is best confirmed by inspection of the conjunctivae and palmar creases. Cardiovascular manifestations of anaemia consist of a high output state with tachycardia and perhaps cardiac failure. If the face and mucous membranes appear plethoric, polycythaemia is suggested and should be confirmed by haemoglobin estimation. A relative polycythaemia may occur in the presence of dehydration. In lymphadenopathy, examination is first carried out from behind, with the patient's neck flexed to relax the sternomastoid muscles. Lymphadenopathy may occur in relationship to the jugular vessels, submandibular and submental regions, and anterior and posterior triangles of the neck. Purpuric spots are spontaneous petechiae or ecchymoses, which represent bleeding into or under the skin. The spots do not blanch on pressure and on fading leave a bluish discolouration as with a bruise. Purpura may be thrombocytopenic or non-thrombocytopenic; it is differentiated by performing a platelet count.