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M Lopez-Hoyos

Publications and source records attributed to M Lopez-Hoyos.

7 recordsLinked to original sources
PubMed2005

Antibodies to carbonic anhydrase and IgG4 levels in idiopathic chronic pancreatitis: relevance for diagnosis of autoimmune pancreatitis.

BACKGROUND: Increased serum antibodies against carbonic anhydrase II (CA-II Ab) or IgG4 levels have been reported in cases of autoimmune chronic pancreatitis (ACP). AIM: To assess the relevance of serum CA-II Ab and IgG4 levels for the diagnosis of ACP in idiopathic CP (ICP) versus alcoholic CP and Sjogren's syndrome (SS). SUBJECTS: This was a multicentre study involving 227 subjects divided into four groups: ICP (n = 54), normal controls (n = 54, paired by age and sex with ICP patients), alcoholic CP (n = 86), and SS (n = 33). METHODS: CA-II Ab was measured by ELISA and confirmed by western blotting. A score of easy clinical use with major clinical, morphological, and biochemical parameters for the diagnosis of ACP was applied. RESULTS: The percentage of patients with increased serum CA-II Ab was higher in the ICP group (28%) than in controls (1.9%) and in patients with alcoholic CP (10.5%), but lower than in patients with SS (64%). The proportion with elevated IgG4 levels was higher in the ICP group (15%) compared with controls (1.9%) and SS (0%) but not significantly different from alcoholic CP (8%). Most ICP patients (7/8) with high IgG4 levels exhibited increased CA-II Ab and a compatible ACP score. A definitive diagnosis of ACP by histological analysis was associated with other autoimmune disorders, an increase in both serum IgG4 and CA-II Ab levels, and IgG4 positive plasma cells. CONCLUSIONS: The increase in serum IgG4 levels was strongly associated with elevated CA-II Ab levels, manifestations compatible with ACP, and lymphoplasmacytic infiltration when surgical specimens were available.

Adolescent↗
PubMed2004

Clinical utility of anti-CCP antibodies in the differential diagnosis of elderly-onset rheumatoid arthritis and polymyalgia rheumatica.

BACKGROUND: In a significant number of patients the differential diagnosis between elderly-onset rheumatoid arthritis (EORA) and polymyalgia rheumatica (PMR) is very difficult because of the lack of specific serum markers. Anti-cyclic citrullinated peptide antibodies (anti-CCP Abs) have recently been shown to be highly specific for rheumatoid arthritis (RA). This is the first study addressing the utility of these antibodies in the differential diagnosis between EORA and PMR. METHODS: Serum samples from 57 EORA patients and 49 PMR patients were studied for the presence of anti-CCP Abs and rheumatoid factor (RF). As controls, samples from 41 RA patients (age at onset <60 yr) and 24 aged healthy subjects were analysed. RESULTS: Sixty-five per cent of EORA patients had anti-CCP Abs, whereas none of the PMR patients or the aged healthy subjects was positive for those antibodies. Ten of the EORA patients started with polymyalgic symptoms and two of them were positive for anti-CCP Abs. Interestingly, there was a significant correlation between anti-CCP Abs and RF in EORA but not in young RA patients. CONCLUSIONS: The presence of anti-CCP Abs in a patient with clinical symptoms of PMR must be interpreted as highly suggestive of EORA.

Age of Onset↗
PubMed2004

Selective T cell receptor decrease in peripheral blood T lymphocytes of patients with polymyalgia rheumatica and giant cell arteritis.

OBJECTIVES: To investigate the phenotype and T cell receptor (TCR) use in peripheral blood T cells in patients with polymyalgia rheumatica (PMR) and giant cell arteritis (GCA). METHODS: Circulating T lymphocyte phenotype and TCR repertoire were studied by flow cytometry using specific monoclonal antibodies in 23 healthy controls and 37 patients with PMR/GCA. RESULTS: Patients with active PMR/GCA showed an inverse relation between naive and memory CD4+ T cells and unchanged expression of activation surface markers compared with controls. CD4+ TCR BV expansions were seen in 12 (52%) controls and in 8 (22%) patients with active disease (p = 0.03). Within the CD8+ subset, the frequency of expansions was similar between groups. Most T cell expansions remained stable over time. Seventeen of the 23 patients with active PMR/GCA disclosed a simultaneous CD4+ and CD8+ T cell depletion for at least one particular BV family with a clear predominance of BV5S2/S3. CONCLUSIONS: The phenotype of circulating T cells in patients with PMR/GCA is similar to that found in aged healthy subjects, except for the surface markers of naive and memory cells and a striking non-activated phenotype. Specific BV expansions in CD4+ and CD8+ T cells, which remain stable over time, are frequent in aged subjects, including patients with PMR/GCA. TCR BV changes in patients with active disease seem to be also age related, except for the significant decrease in certain BV families in both CD4+ and CD8+ T cell subsets, which may favour the participation of a superantigen stimulation in PMR/GCA.

Aged↗
PubMed2003

Homocysteine levels in polymyalgia rheumatica and giant cell arteritis: influence of corticosteroid therapy.

OBJECTIVES: It has been suggested that patients with giant cell arteritis (GCA) may share a common pathway with atherosclerosis. Furthermore, patients with GCA and polymyalgia rheumatica (PMR), in addition to advanced age, are treated for prolonged periods of time with corticosteroids, a factor that can also accelerate atherosclerosis. Hyperhomocysteinaemia is considered an independent risk factor for atherosclerosis, and might play a role in ischaemic manifestations that occur with a variable frequency during the course of GCA. The purposes of the present study were: (i). to analyse the plasma levels of homocysteine in patients with GCA and PMR, (ii). to determine the influence of corticosteroid therapy on the homocysteine levels and (iii). to analyse if the levels of homocysteine may predict the development of ischaemic complications in patients with GCA. METHODS: Plasma homocysteine concentration was measured in 56 patients with active PMR/GCA (17 GCA and 39 isolated PMR) before steroid treatment and 23 healthy age-matched volunteers were used as controls. The total plasma homocysteine level was quantified using a fluorescent polarization immunoassay. RESULTS: Homocysteine concentrations were higher in PMR and GCA patients than age-matched controls (P < 0.05). Patients with GCA had slightly higher levels of plasma homocysteine than those with isolated PMR (13.6+/-4.3 vs 12.7+/-3.1 micromol/l, P=0.6). In 30 of these patients (12 GCA and 18 PMR) a second measurement of homocysteine concentration was done when they were in clinical remission with steroid treatment. The post-treatment levels of homocysteine were significantly increased in GCA rather than in PMR patients. In 13 patients with homocysteine levels above the normal upper limit of our laboratory, therapy with folic acid and/or vitamin B12 was started. After 3 months of vitamin supplements, the homocysteine concentration significantly decreased from 19.2+/-3.1 to 13.6+/-3.2 micromol/l (P=0.001). Such decrease was less marked in the PMR than in GCA patients. Ten out of the 17 patients with GCA had ischaemic manifestations of the disease. The levels of homocysteine were slightly higher in GCA patients with ischaemia than in those without ischaemic manifestations, although the difference did not reach statistical significance (15+/-4.9 vs 11.6+/-1.9 micromol/l, P=0.46). CONCLUSIONS: Patients with active PMR and GCA had elevated plasma concentrations of homocysteine. Corticosteroid therapy significantly increased such levels, especially in GCA patients. Treatment with supplements of folic acid and/or vitamin B12 reduced the homocysteine concentrations. These data support the hypothesis that patients with GCA (and to a lesser extend PMR patients) may share a common pathway with atherosclerosis and suggest a new atherogenic mechanism of corticosteroids.

Aged↗
PubMed2002

Reactive arthritis after BCG immunotherapy: T cell analysis in peripheral blood and synovial fluid.

OBJECTIVE: To investigate the pathogenic mechanism of reactive arthritis after instillation of Calmette-Guérin bacillus (BCG). Although the clinical features of reactive arthritis after BCG therapy are well described, only a few reports have studied the possible pathogenic mechanisms. METHODS: We analysed by flow cytometry the phenotype and T-cell receptor (TCR) expression of peripheral blood (PB) and synovial fluid (SF) T cells in a patient who developed reactive arthritis (ReA) following intravesical BCG immunotherapy for bladder cancer. The proliferative response of short-term T-cell lines (TCL) from PB of this patient to mycobacterial antigens was tested by bromodeoxyuridine incorporation. RESULTS: CD4(+) and CD8(+) SF T cells with activated and memory phenotype were observed at the onset of arthritis. We were able to detect BV-restricted expansion of CD8(+) T cells in PB (BV17) and in SF (BV5S1 and BV12). The percentage of PB and SF CD8(+) T cells that expanded diminished when the symptoms remitted. The strongest response of CD4(+) TCL from the patient in vitro was obtained for human hsp-60 in an inversely dose-dependent manner. Very important was the finding that CD8(+) TCL from the patient demonstrated no proliferative response to any antigenic challenge that was reversed after the addition of exogenous interleukin 2. CONCLUSION: Although the identity of the stimulating antigen that led to the expansions observed in this patient is not clarified by the present data, both CD4(+) and CD8(+) T cells might play a role in the development of ReA following intravesical administration of BCG.

Arthritis, Reactive↗
PubMedDate not supplied

Familial aggregation of polymyalgia rheumatica and giant cell arteritis: genetic and T cell repertoire analysis.

OBJECTIVE: Several reports of familial aggregation of giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) have been described although detailed genetic and immunological studies are scarce. Our aims were to investigate the influence of HLA-DRB1 alleles and to analyze the phenotype and T cell receptor (TCR) usage of circulating T lymphocytes in a familial case of GCA and PMR. METHODS: HLA-DRB1 typing was carried out using polymerase chain reaction amplification with specific primers. The study of the circulating T cell repertoire was performed by staining with specific monoclonal antibodies and flow cytometry analysis. RESULTS: Patient 1 developed GCA at the age of 71, four years prior to the diagnosis of PMR in her older brother. The HLA-DRB1 typing of Patient 1 was DRB1*04 (DRB1*0401)/DRB1*12 and in Patient 2 was DRB1*07/DRB1*12. In our patient population, GCA was associated with an increased frequency of HLA-DRB1*04 compared with PMR patients. Regarding T cell phenotype, the brother with active PMR had a higher expression of surface markers indicating activation in both T cell subsets (CD25 and HLA-DR). The sister with GCA showed a pronounced decrease of CD4+/CD45RA+ T cells with respect to her brother with PMR. Both patients carried a significant depletion of CD28 in both subsets, specially within the CD8+ T cell compartment. The BV gene usage differed from one patient to the other. T cell expansions were identified in both patients but the specificities were different. CONCLUSION: We describe an association of GCA and PMR between two first degree relatives with significant genetic and immunologic differences. Our results suggest that the pathogenic mechanisms leading to the development of GCA and PMR are probably multifactorial, and both genetic and environmental factors may contribute to the development of these diseases.

Aged↗