Page 405 - Essential Haematology

Chapter 28 Haematological changes in systemic disease / 391

hypocellular or fibrotic. Dysplastic features are cular haemolysis is marked with haemoglobinuria.

common, with ineffective thrombopoiesis or granu- This may be associated with quinine therapy ( ‘ black-

locyte formation accounting at least in part for the water fever ’ ). Thrombocytopenia is commonly
cytopenia. The myelodysplasia does not show the found in acute malaria. Patients with chronic

chromosome abnormalities found in classic myelo- malaria have an anaemia of chronic disorders;
dysplasia and does not appear to be pre - leukaemic. hypersplenism may contribute to the anaemia and
Thrombocytopenia is treated if necessary by corti- result in moderate thrombocytopenia and neutro-

costeroids, high - dose gammaglobulin infusions or penia. Tropical splenomegaly (see p. 144 ) is prob-

by other therapies for immune thrombocytopenia ably a chronic immune reaction to malaria.

(see p. 336 ), or by antiretroviral therapy. Dyserythropoiesis in the marrow, folate defi ciency
Anaemia is also common, like the other cytope- and protein - calorie malnutrition may contribute to
nias, and more severe as the disease progresses. anaemia.
It is usually multifactorial in origin – the anaemia
of chronic disorders, marrow dysplasia and drug
Toxoplasmosis
therapy, especially zidovudine. Serum vitamin
B 12 is often low, most likely because of intestinal Toxoplasmosis in children and adults is associated
malabsorption, but the anaemia does not respond with lymphadenopathy and large numbers of atypi-
to vitamin B 12 therapy. Blood transfusions cal lymphocytes in the blood. Congenital disease
or recombinant erythropoietin injections are may be confused with hydrops fetalis in a severely
needed. anaemic hydropic infant with gross hepatosplenom-
Increased plasma cells in the marrow and poly- egaly, thrombocytopenia or a leucoerythroblastic
clonal increase in immunoglobulins are frequent. A blood fi lm.
paraprotein is present in 5 – 10% but appears benign.
Non - Hodgkin lymphoma, in over 90% high grade,

Kala - a zar ( v isceral l eishmaniasis)
both systemically and in the central nervous system,
occurs in HIV infected individuals with over 100 The visceral form of leishmaniasis is associated with

times the frequency expected in the general popula- pancytopenia, hepatosplenomegaly and lymphade-

tion. Diffuse large B - cell lymphomas are most nopathy. Bone marrow or splenic aspirates may

common, with 20% confined to the central nervous show large numbers of parasitized macrophages
system; a substantial minority are Burkitt lym- (Fig. 28.9 ).
phoma. Hodgkin lymphoma, usually of poor prog-
nosis type, is also increased in frequency. EBV
Other p arasitic d iseases
infection appears to usually underlie this as well as
Burkitt lymphoma. In the acute phase of both African and South
Treatment of lymphomas in the setting of HIV American trypanosomiasis, organisms are found in
is with standard regimens. Continuation of antiret- the peripheral blood (Fig. 28.10 ). Microfi lariae of

roviral therapy exaggerates the tendency to cytope- bancroftian filariasis and loiasis are also detected

nia induced by chemotherapy so prophylaxis against during blood film examination (Fig. 28.11 ). In
opportunistic infections is important. Th e bone chronic schistosomiasis, hypersplenism follows the
marrow may indeed reveal the presence of oppor- splenic enlargement associated with portal hyper-
tunistic infection (Fig. 28.7 a,b). tension. In many parasitic diseases there is eosi-
nophilia (Table 28.5 ).
Malaria
Osteopetrosis
Some degree of haemolysis is seen in all types of

malarial infection. The most severe abnormalities Osteopetrosis is a rare genetic disorder in which there
are found in Plasmodium falciparum infections (Fig. is an increase in bone mass with skeletal abnormality
28.8 ). In the worst cases, DIC occurs and intravas- and bone marrow failure. It is caused by defects in a