Increased circulating levels of transcobalamin II in typhoid fever.

ABSTRACT

Many previous studies have shown that serum transcobalamin II (TCII) is usually elevated in patients with a stimulated and proliferative reticuloendothelial system resulting from such diseases as multiple myeloma, systemic lupus erythrematosus, dermatomyositis, rheumatoid arthritis and Gaucher’s disease. As reactive macrophage hyperplasia with monocytosis also occurs in patients with typhoid fever, we therefore studied TCII in these patients. The mean value of serum TCII was significantly higher in the typhoid patients’ group, and 15 out of 35 patients had serum TCII values over 2,000 pg/ml. There was no relationship between serum TCII and white blood count, haemoglobin or haematocrit values. The increased serum TCII level in typhoid patients was possibly due to increased synthesis by the proliferative mononuclear cells derived from reticuloendothelial tissue in various organs such as the spleen, liver and mesenteric lymph nodes. This supposition is supported by a previous report that TCII is synthesized in part by mouse peritoneal macrophages, as well as by human monocytes and macrophages which produced and secreted considerable amounts of TCII into the medium. Findings of increased serum TCII in typhoid patients therefore add a new area of information which has never been studied before.