Acute leukaemia

11.6 Acute leukaemia



Joseph Ting




Essentials



1 At its most severe, acute leukaemia leads to diffuse bone marrow infiltration and failure. Pancytopenia including neutropenia, anaemia and thrombocytopenia as well as extramedullary hematopoiesis give rise to classical symptoms of infection susceptibility, easy fatigability, bleeding diathesis and hepatosplenomegaly.

2 ED supportive treatment in conjunction with a paediatric haematologist includes broad spectrum antimicrobial administration or sepsis resuscitation, packed red blood cell transfusion for symptomatic or critical anaemia and platelet replacement if the child has high potential or actual risk of thrombocytopenia-related bleeding.


Introduction


The leukaemias are a group of diseases characterised by the clonal proliferation of malignant immature white blood cell precursors. They differ in the lineage and degree of differentiation of cells involved, being broadly divided into two groups: lymphoid and myeloid. These two categories are further subdivided into an acute form that progresses more rapidly than the chronic disease, which is relatively indolent. Preconceptional germ cell and postnatal environmental exposure to electromagnetic radiation and carcinogens may play a role,1–3 with higher risk in children with congenital neutropenia, Down’s syndrome and Fanconi anaemia.4 Previous chemotherapy and radiotherapy are associated with increased risk of a secondary malignancy. Acute lymphoblastic leukaemia (ALL) comprises four-fifths of childhood leukaemia,4 with acute myeloid leukaemia (AML) and chronic myeloid leukaemia (CML) accounting for 15% and 2%.5 Together they account for one-third of all malignancies in children under 15 years old. Although children of all ages are affected, the peak incidence is between 2 and 6 years.



Classification


Leukaemogenesis represents clonal proliferation of white blood cells arrested at various stages of differentiation, lending itself to diagnostic and prognostic classification based on the cell line affected, degree of differentiation, immunophenotyping, cell receptor, cell antigen and chromosomal studies. Classification of leukaemia is complex, with the French–American–British (FAB) categories being useful for AML and immunotyping better suiting ALL.4,5



Clinical presentation


Signs and symptoms in ALL and AML are similar and depend on the degree of marrow infiltration and extent of extramedullary involvement. The first symptoms are non-specific including lethargy, bone pain and loss of appetite. Classic findings in acute leukaemia include fever/infection, pallor/lethargy/easy fatigability and bruising/mucosal bleeding due to febrile neutropenia, anaemia and thrombocytopenia, respectively. Marrow infiltration leads to bone pain and extramedullary spread leads to painless adenopathy (including mediastinal), hepatomegaly, splenomegaly, skin or periorbital infiltrates and rash. Difficulty with diagnosis arises in differentiating early acute from chronic disease, when symptoms (night sweats, arthralgia, bone pain, constitutional symptoms) and signs (enlarged liver and spleen, lymphadenopathy) are variable and non-specific. Central nervous system (CNS) involvement occurs in 4% of children (cranial nerve palsy, cord compression) and testicular leukaemia in 10% of boys (painless enlarged testes). Hyperviscosity results in tissue infarction (CNS, pulmonary) and rarely priapism results from leucocyte sludging and cavernosal obstruction.

Related posts:

Syncope Abdominal and pelvic trauma Paediatric advanced life support (PALS, APLS) Pertussis Infective endocarditis Default ThumbnailAvailing web-based resources

Stay updated, free articles. Join our Telegram channel
Tags:
Sep 7, 2016 | Posted by in EMERGENCY MEDICINE | Comments Off on Acute leukaemia

Full access? Get Clinical Tree
Get Clinical Tree app for offline access