Page 495 - Medicine and Surgery

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BLUK007-12 BLUK007-Kendall May 12, 2005 20:37 Char Count= 0

Chapter 12: Paraproteinaemias 491

Clinical features Age
Marrow infiltration results in anaemia, thrombocy- Onset most commonly aged 60 years.

topenia and leucopenia.
Lytic bone lesions most commonly in the axial skele-

Sex
tonmay result in pathological fractures and bone
M > F
pain. Spinal cord compression occurs in approx-
imately 10–20% of patients at some time during
Pathophysiology
the course of disease. Hypercalcaemia causes thirst,
The abnormal proliferation of lymphoplasmacytoid
polyuria, constipation and abdominal pain.
cellsproduces high levels of IgM, which polymerises and
Renal failure.

results in increased plasma viscosity. Marrow infiltration
may result in pancytopenia.
Investigations
The diagnosis of myeloma is made if there are:
Clinical features
Bone marrow aspirate has at least 10–15% plasma

Hyperviscosity presents as weakness, tiredness, confu-
cells.
sion and coma. Platelet opsonisation results in a func-
Lytic lesions on skeletal survey.

tional deficiency and hence an increased risk of bleed-
Monoclonal immunoglobulins in the urine or blood.

ing. Patients also often have peripheral lymphadenopa-
Other investigations include:
thy. Marrow failure may lead to symptoms and signs of
FBC may show signs of marrow infiltration anaemia,

anaemia, recurrent infections and bleeding.
thrombocytopenia, leucopenia.
The ESR is raised if there is a serum paraprotein.

Investigations
Serum calcium may be raised.

Full blood count: Haemoglobin, white cell count and
Hyperuricemia due to increased cell turnover.

platelets may be low or normal.
Bone marrow demonstrates lymphoplasmacytoid cell

Management infiltration.
Chemotherapy with single alkylating agents improves Protein electrophoresis shows an IgM parapro-
prognosis. High dose combination chemotherapy with teinaemia.
or without haemapoetic progenitor cell transplantation Plasma viscosity is raised.
is used in younger patients. Recently, thalidomide has
been demonstrated to produce a significant response
Management
in 30% of patients whose disease progressed following
Chemotherapy produces a variable response. Plasma-
other therapy. Supportive care includes blood transfu-
pheresis is used for symptomatic hyperviscosity.
sion, radiotherapy for localised bone pain, correction of
hypercalcaemia with bisphosphonates and management
of renal impairment. Monoclonal gammopathy of
undetermined significance (MGUS)
Waldenstr ¨ om macroglobulinaemia Definition
An abnormal clone of plasma cells producing a mildly
Definition raised monoclonal immunoglobulin without features of
Lymphoplasmacytoid proliferation resulting in a high multiple myeloma.
levelofamacroglobulin(IgM),elevatedplasmaviscosity
and bone marrow infiltration.
Aetiology/pathophysiology
The immunoglobulin secreted is normally IgM. It poly-
Incidence merises and causes a mild increase in plasma viscosity.
0.5 per 100,000 per year. Unlike multiple myeloma there are preserved levels of