Osteoporosis en enfermedades reumáticas / Osteoporosis in rheumatic diseases

La osteoporosis es una enfermedad compleja que resulta de la interacción de células del sistema óseo, principalmente osteoblastos, osteoclastos y osteocitos, que está regulada por varias hormonas y citokinas que interactúan sobre un variado sistema de transducción de señales que derivan en reabsorción o formación de hueso. En varias enfermedades reumáticas este delicado balance se pierde por efecto de la enfermedad misma, aunque también influye poderosamente el tratamiento empleado. En este artículo se revisa el mecanismo general de la fisiología del tejido óseo y su alteración por la inflamación, que son la base de las enfermedades reumáticas. También se revisa la pérdida de masa ósea inducida por esteroides y su tratamiento.

Osteoporosis is a complex disease that results from the interaction of cells in the bone marrow, mainly osteoblasts, osteoclasts and osteocytes, which is regulated by several hormones and cytokines that interact on a variety of signal transduction system that lead to bone resorption or formation. In several rheumatic diseases this delicate balance is lost due to the disease itself, but also strongly influenced by the treatment used. This article reviews the general mechanism of bone physiology and its alteration by inflammation, which are the basis of rheumatic diseases. We also review the bone loss induced by steroid and its treatment.

Manifestaciones clínicas de la granulomatosis de Wegener y la poliangeítis microscópica en Santiago-Chile, 1990-2001 / Clinical features of Wegener granulomatosis and microscopic polyangiitis in Chilean patients

Background: Systemic vasculitis are a group of heterogeneous diseases characterized by inflammation and necrosis of blood vessel walls. The etiology is not known, but geographic and environmental factors are implicated. Aim: To describe the clinical features of microscopic polyangiitis (MPA) and Wegener's granulomatosis (WG) in a Chilean cohort of patients. Patients and methods: Retrospective review of the medical records of 123 patients with the diagnosis of systemic vasculitis (65 MPA and 58 WG), seen from 1990 to 2001. The diagnosis were made based on the American College of Rheumatology and Chapel Hill criteria. Results: The mean follow-up for MPA was 15 months (1-120) and for WG, 20 months (1-120). The median age (years) at diagnosis for MPA was 61 (19-82) and WG 50 (20-82). Gender distribution was similar in both groups (male: 68percent and 57percent respectively).The main clinical features in the MPA group were renal involvement (68percent), peripheral nervous system involvement (57percent), pulmonary hemorrhage (28percent), and skin disease (32percent). In the WG group were alveolar hemorrhage (62percent), renal involvement (78percent), paranasal sinus involvement (57percent), and ocular disease (26percent). In both, creatinine levels above 2.0 mg/dl were associated with a higher mortality (p< 0.01). ANCA by immunofluorescence was performed in 56 MPA patients (75percent had pANCA, 4percent had cANCA and 21percent were ANCA negative) and in 55 WG patients (17percent had pANCA, 79percent had cANCA and 4percent were ANCA negative). Global mortality was 18percent and 17percent respectively, and the most common causes of death were infections. Conclusions: The clinical features of our patients are similar to other published data. In our WG and MPA patients the main predictor for death was a serum creatinine above 2 mg/dl.

Curso clínico de la nefropatía membranosa lúpica pura / Long-Term outcome of type V lupus membranous glomerulonephritis

Background: The long-term outcome of the pure form of WHO type V lupus membranous glomerulonephritis is apparently more benign than that of other forms of lupus glomerulonephritis. However 12percent of such patients progress to terminal renal failure. The presence of proteinuria may be an indication of cytotoxic agents. Aim: To study the clinical long-term outcome of WHO type V lupus membranous glomerulonephritis. Material and methods: A retrospective analysis of all kidney biopsies of a University Pathology Department, with the diagnosis of WHO type V lupus membranous glomerulonephritis. Review of medical records of patients with the disease and one clinical assessment of all living patients. Results: Between 1973 and 2000, 703 kidney biopsies were done to patients with systemic lupus erythematosus. Of these, 40 were membranous glomerulonephritis and in 33 patients (28 women, age range 6-71 years), data on the evolution and survival was obtained. Nineteen had type Va and the rest type Vb nephritis. Two presented with renal failure and 11 with proteinuria over 3.5 g/24h. The median follow-up since the renal biopsy was 63 months (range 1-316). At the end of follow-up, four had a creatinine clearance of less then 15 ml/h and four a clearance between 15 and 29 ml/h (one of these received a renal allograft). Eleven (33percent) patients had died, mostly due to infections. Life expectancy at five years with a creatinine clearance over 15 ml/h was 75percent. Bad prognostic factors were an elevated creatinine clearance over 15 ml/h was 75percent. Bad prognostic factors were an elevated creatinine and high blood pressure at the moment of the biopsy. Conclusions: The clinical outcome of these patients was bad. Twelve percent reached a stage of terminal renal failure. This is in contrast with the 3percent progression to a similar stage of proliferative glomerulonephritis treated with i.v. cyclophosphamide. New therapies for this condition must be sought.

Tratamiento con ciclosporina de la artritis reumatoídea refractaria / Treatment of refractory rheumatoid arthritis with cyclosporine

Cyclosporine may be useful in the treatment of rheumatoid arthritis refractory to other immunosupressive agents, in doses of less than 10 mg/kg/day to minimize its nephrotoxic potential, that is enhanced with prolonged use of concomitant administration of antiinflammatory drugs. We report 15 patients aged 50 ñ 12 years with erosive rheumatoid arthritis lasting 5 ñ 4 yeras and refractory to other immunosupressive agents. They were studied during one year and received cyclosporine in initial doses of 2.5 mg/kg/day that were increased to 5 mg/kg/day, assessing clinical response, blood pressure and serum creatinine. Nine patients, that received a maximal dose of 3.4 ñ 0.7 mg/kg/day during 7 ñ 4 months, improved; a 30 percent increase in creatinine was observed in 3, blood pressure raised in six and 2 bad hepatic toxicity. in the 6 patients that did not improve, the mean treatment lapse was 4 ñ 3 months and the maximal dose achieved was 2.7 mg/kg/day; creatinine increased in one and blood pressure increased in 4. It is concluded that although the clinical response to cyclosporine was good, only 4 patients completed one year of treatment, due to the frequent secondary effects of the drug