<unk>  can be either primary (unknown cause) or secondary (a result of another pathology/ caused by an underlying condition). Primary<unk>  The primary form is caused by excessive cell proliferation of B lymphocytes, characterized by clonal lymphoproliferative disorder. Primary<unk>  occurs after the fifth decade of life and peaks prevalence in a person's 70s and 80s. Secondary<unk>  Secondary cold<unk>  syndrome occurs when autoantibodies bind to red blood cells, rendering them subject to attack by the complement system. It is a result of an underlying condition potentially associated with either monoclonal cold-reacting autoantibodies or polyclonal cold-reacting autoantibodies predominantly caused by infection or lymphoproliferative disorders. In adults, this is typically due to: * Bacterial infections such as mycoplasma, Legionnaires'<unk> , syphilis, listeriosis, or E. coli. * Viral infections such Epstein-Barr virus, cytomegalovirus, mumps, varicella, rubella, adenovirus, HIV, influenza, or hepatitis C. * Parasitic infections such as malaria or trypanosomiasis. * Other autoimmune<unk> s such as systemic lupus erythematosus. * Certain types of cancers such as lymphoma, chronic lymphocytic leukemia, Waldenström macroglobulinemia, multiple myeloma, and Kaposi sarcoma. In children,<unk>  is often secondary to an infection, such as Mycoplasma pneumonia, mononucleosis, and HIV. Inheritance<unk>  is not an inherited condition. It is designated as either primary (unknown cause) or secondary (associated with or caused by another condition). In some cases, cold<unk>  may be multifactorial which means that multiple environmental factors and genes likely interact to predispose a person to developing the condition. However, to our knowledge, no<unk> -causing genes have been identified and no familial cases have been reported.
Cold agglutinin disease
Atypical hemolytic uremic syndrome
MERRF syndrome
Serum sickness
Cold autoimmune hemolytic anemia
Michels Caskey syndrome
Hennekam syndrome
Uddanam nephropathy