Abnormalities in coagulation, gammopathies, throm-botic thrombocytopenia purpura, porphyria cutanea tarda, and diffuse infiltrative CD8 lymphocytosis syn-drome have also been reported in patients with HIV in-fection. Some contributing factors to these abnormalities include genetically determined cellular immune re-sponses to HIV, problems with heme synthesis, whereas others remain unclear.56 Although these conditions rep-resent additional hematologic abnormalities in HIV, they are beyond the scope of this article and will not be dis-cussed in depth.