Neopterin in AIDS, other immunodeficiencies, and bacterial and viral infections

Abstract

An increase in total urinary neopterin was observed in 12 of 13 patients with acquired immunodeficiency syndrome (AIDS), seven of 13 patients with lymphadenopathy, one of six healthy homosexual males, seven of ten adult patients with staphylococcal pneumonia, 11 of 12 children with viral infections, four of seven children with bacterial infections, and 12 of 13 children with various immune defects. Extremely high values of total urinary neopterin and monapterin were observed in severely ill patients with AIDS and those with familial hemophagocytic lymphohistiocytosis. Neopterin excretion was normal in two AIDS patients with Kaposi's sarcoma, but without opportunistic infections at that time. On reexamination of one of these patients later on, elevated neopterin values were noted. Parallel increases in neopterin and monapterin were found, whereas biopterin was usually normal. The increase in total neopterin was mainly due to 7,8-dihydroneopterin and was accompanied by an increase in 3'-hydroxysepiapterin. Increased neopterin in urine is assumed to reflect the increase in GTP pool and GTP cyclohydrolase I activity as observed in stimulated monocytes. Thus, neopterin, as a measure of the activation of the nonspecific cellular immune system, may be used diagnostically to detect allograft rejection after transplantations and to follow-up HTLV-III positive patients.

Elevated circulating levels of interleukin-1 receptor antagonist but not IL-1 agonists in hemophagocytic lymphohistiocytosis

“…Previous studies on children with FHL have revealed increases in serum levels of TNF, IFN-gamma, neopterin sIL-2r, IL-6, and sCD8 [4, 9,10]. In the present study we have demonstrated that, in addition to the cytokines previously studied, circulating IL-lra is also elevated in active disease and that this alteration is reversible, i.e., patients in remission have values within normal limits (Fig.…”

Is there any relationship between serum and urine neopterin and serum interferon‐γ levels in the activity of Behcet's disease?

“…7 The elevation of neopterin levels in body fluids, especially serum and urine, was reported to be correlated. 27,30 Investigators point out that measurement of urine neopterin levels could be more meaningful because urine neopterin levels are at least 500-1000 times higher than serum neopterin levels. 31 In active periods of many diseases with inflammation in their course, as neopterin levels rise in body fluids, it can be considered that cell-mediated immunity primarily causes relapse, or factors causing relapse can affect cell-mediated immunity.…”

“…25,26 After recognition of neopterin being a non-specific marker of cell-mediated immune system activation, neopterin levels were observed as elevated in body fluids during the activation period of many diseases and it was thought to be helpful in BD to determine the activity of the disease. 9,11,[27][28][29] Response to treatment and prognosis can also be evaluated by following up neopterin levels in body fluids. 7 The elevation of neopterin levels in body fluids, especially serum and urine, was reported to be correlated.…”

Changes in serum neopterin and serum beta 2-microglobulin in subjects with lung infections

“…Extracellular bacterial infections are not commonly linked with activation of the cellular immune system. However, NIEDERWIESER et al [14] observed elevated neopterin in patients with staphylococcal pneumonia, and others [15,16] found increased β 2 -microglobulin levels in cerebrospinal fluid in bacterial meningitis. The primary barrier against lung infection with extracellular bacteria depends on antibodies and phagocytosis by alveolar macrophages and polymorphonuclear leucocytes.…”