Blood disorders or diseases symptoms? What type?

Dear SumGuy, I am sorry about the loss of your cousin. Because a list of blood disorders would fill a couple of pages, I'll limit my comments to your cousin's diagnosis of HLH which stands for hemophagocytic lymphohistiocytosis (HLH), a rare but potentially fatal condition in which certain white blood cells (histiocytes and lymphocytes) build up in organs including the skin, spleen, and liver, and destroy other blood cells. This causes fever and damages the liver and spleen, resulting in enlargement of these organs. HLH may be inherited or caused by certain conditions or diseases, including infections, immunodeficiency (inability of the body to fight infections), and cancer. It most commonly affects young infants and children, There are two forms of HLH, familial(inherited) HLH and acquired HLH. Familial HLH is passed through families in an recessive fashion. Familial HLH accounts for about 25% of HLH cases. Acquired HLH is not inherited and is associated with infections, transplantation, cancers, rheumatologic disorders, and treatment of a variety of conditions. The best treatment options are determined by a number of factors, including disease severity, age of onset, presence of familial disease, and associated conditions. The goal of treatment is to suppress inflammation and induce remission. Some references include: Fisman DN. Hemophagocytic Syndromes and Infection. Emerging Infectious Diseases. March 2009;:. Available at: http://www.cdc.gov/ncidod/eid/vol6no6/fisman.htm. July 21, 2011. Familial hemophagocytic lymphohistiocytosis. Genetics Home Reference. January 2011 Available at: http://ghr.nlm.nih.gov/condition/familial-hemophagocytic-lymphohistiocytosis. Accessed July 22, 2011. Gans HA, Lewis DB. Long: Principles and Practice of Pediatric Infectious Diseases, 3rd ed. In: . Hemophagocytic lymphohistiocytosis and macrophage activation syndrome. Philadelphia, PA:Churchill Livingstone; 2008: