Altered circadian rhythms in rheumatoid arthritis patients play a role in the disease's symptoms.

The circadian changes in the metabolism or nocturnal secretion of endogenous corticosteroids (reduction) observed in rheumatoid arthritis (RA) patients are responsible, in part, for the time-dependent changes that are observed in the inflammatory response and related early morning clinical symptoms of the disease. Melatonin (MLT), another circadian nocturnal hormone that is the secretory product of the pineal gland, has been implicated in the time-dependent RA inflammatory reaction with effects that are opposite to those of corticosteroids. As a consequence, altered functioning of the HPA axis (early morning reduced corticosteroid production) and of the pineal gland (night increased MLT production) found in RA patients, seem to be important factors in the appearance and perpetuation of the clinical circadian symptoms of the disease.

Nocturnal hormones and clinical rhythms in rheumatoid arthritis.

It is well known that some clinical signs and symptoms of rheumatoid arthritis (RA) vary within a day and between days; the morning stiffness that is observed in patients who have RA has become one of the diagnostic criteria of the disease. The circadian changes in the metabolism or nocturnal secretion of endogenous corticosteroids is certainly responsible, in part, for the time-dependent changes that are observed in the inflammatory response and related clinical symptoms. More recently, melatonin (mLT), another circadian nocturnal hormone that is the secretory product of the pineal gland, has been implicated in time-dependent inflammatory reactions, with effects that are opposite of those of corticosteroids.

Circadian melatonin and cortisol levels in rheumatoid arthritis patients in winter time: a north and south Europe comparison.

Background: Altered functioning of the hypothalamic-pituitary-adrenal axis and altered melatonin production might modulate the circadian symptoms in patients with rheumatoid arthritis.

Objective: To investigate the influence of different winter photoperiods on the circadian rhythms of serum melatonin, cortisol, tumour necrosis factor alpha (TNFalpha), and interleukin 6 (IL6) in patients with rheumatoid arthritis from a north Europe country (Estonia) and a south Europe country (Italy).

Methods: The patients from Estonia (n = 19) and Italy (n = 7) had similar disease severity and duration and were compared with healthy age and sex matched controls in the two countries.

Use of a peptide based enzyme immunoassay in diagnosis of Chlamydia trachomatis triggered reactive arthritis.

Objective: To assess the presence of circulating IgA and IgG antibodies to Chlamydia trachomatis in sera of patients with reactive arthritis (ReA) and other arthritides.

Methods: A peptide based enzyme immunoassay (EIA) was used to study 132 patients divided into 5 groups: C. trachomatis triggered ReA, uroarthritis, enteroarthritis, oligoarthritis, and rheumatoid arthritis (RA).