Tag: subgroups

Decreased natural killer cell activity is associated with severity of chronic fatigue immune dysfunction syndrome

Abstract:

Natural killer (NK) cell activity was measured blindly in vitro with blood specimens from 50 healthy individuals and 20 patients with clinically defined chronic fatigue immune dysfunction syndrome (CFIDS) who met the criteria established by the Centers for Disease Control and Prevention (Atlanta).

In accordance with a group scoring system of 1-10 points, with 10 being the most severe clinical status, the patient population was stratified into three clinical groups: A (> 7 points), B (5-7 points), and C (< 5 points). NK cell activity was assessed by the number of lytic units (LU), which for the 50 healthy controls varied between 20 and 250 (50%, 20-50 LU; 32%, 51-100 LU; 6%, 101-130 LU; and 12%, > 150 LU).

In none of the 20 patients with CFIDS was the NK cell activity > 100 LU. For group C, the 10 patients stratified as having the least severe clinical condition, the measure was 61.0 +/- 21.7 LU; for group B (more severe, n = 7), it was 18.3 +/- 7.3 LU; and for group A (most severe, n = 3), it was 8.0 +/- 5.3 LU.

These data suggest a correlation between low levels of NK cell activity and severity of CFIDS, which, if it is confirmed by additional studies of larger groups, might be useful for subgrouping patients and monitoring therapy and/or the progression of CFIDS.

 

Source: Ojo-Amaize EA, Conley EJ, Peter JB. Decreased natural killer cell activity is associated with severity of chronic fatigue immune dysfunction syndrome. Clin Infect Dis. 1994 Jan;18 Suppl 1:S157-9. http://www.ncbi.nlm.nih.gov/pubmed/8148445

 

Defining the chronic fatigue syndrome

Abstract:

The recently published working definition of the chronic fatigue syndrome (CFS) is a necessary first step toward a consistent effort to research this controversial illness. Before this definition was developed, cases often were defined vaguely, according to the perceptions and biases of the individual researchers, so that the results of some studies were unclear. However, few specific diagnostic parameters for CFS exist, and the new definition may not delineate a single clinicopathologic entity.

Future efforts at researching this illness should be aimed at identifying parameters that differentiate CFS from psychiatric conditions such as major depression and from other defined chronic diseases. Because CFS may be the result of multiple disease processes, the separate study of well-defined subgroups of patients with CFS is appropriate.

Such subgroups of patients are probably more likely to have common pathogenetic features than are patients with CFS as a whole group.

 

Source: Holmes GP. Defining the chronic fatigue syndrome. Rev Infect Dis. 1991 Jan-Feb;13 Suppl 1:S53-5. http://www.ncbi.nlm.nih.gov/pubmed/2020802