General symptoms of leukemia==bleeding,bruising problems,increased risk of infections,(assume===fever,tiredness,)---generally due to lack of normal blood cells===so blood tests help to Dx or assess.Acute leukemias generally are more common in children.So based on age in Question, we can clinically rule out leukemia. Chronic leukemia==Generally common in older age groups. (just a general rule,), so based on age on Question,chronic leukemia can be ruled out. But confusing aspect in Question which is common to both leukemias is possible hepatosplenomegaly,fever,pallor,generalized lymphadenopathy.Becoz these signs and symptoms are common to both leukemias with few exceptions.----Generally B cell symptoms) Lymphomas===Generally primary presentation in lymphoma is lymphadenopathy,B cell symptoms.Definitive diagnosis--lymph node biopsy,but blood tests would also help.Burkitt lymphoma common in children.Diffuse large-B cell lymphoma is the most common non-hodgkins lympoma and occur in adult age group,where as multiple myeloma is most common in older age groups.Generally,lymphomas are common in older adults and older age group with few exceptions and these exceptions are obvious. Leishmaniasis is considered one of the classic causes of markedly enlarged spleen and liver,and present with fever,pallor(anemia),lymphadenopathy.Dx--aspirates from infected skin,liver,spleen,lymphnode.