Tumor-induced osteomalacia: lessons learned.

Tumor-induced osteomalacia is a rare acquired metabolic disorder characterized by hypophosphatemia and inappropriately low serum levels of 1,25-dihydroxyvitamin D. Symptoms include chronic muscle and bone pain, weakness, and fatigue in association with a high risk of fragility fractures due to osteomalacia. The diagnosis is commonly delayed for years due to the nonspecific nature of the presenting symptoms, failure to include determination of serum phosphorus levels in blood chemistry testing, and difficulty in identifying the responsible tumor.

Predominance of T cells in the lymphocytic infiltrates of synovial tissues in rheumatoid arthritis.

Synovial tissues from 5 patients with rheumatoid arthritis (RA) were examined immunofluorescence microscopy for the presence of lymphocytes with either bone marrow-derived (B) or thymus-derived (T) surface markers. Five synovial tissues with severe to mild lymphocytic infiltrations by bright field microscopy were examined in parallel with immunofluorescence. B cells were identified with a pepsin-digested fluoresceinated anti-F (ab')2 antiserum and T cells were detected with a specific rabbit and anti-T lymphocyte antiserum.

Autoimmune disease etiology--a perplexing paradox or a turning leaf?

Autoimmune diseases such as rheumatoid arthritis, systemic lupus erythematosus, or scleroderma have been considered to represent disorders associated with reaction of the patient's own immune system against self-antigens or body systems. In many such disorders, tissues involved show lesions or morphology indicating destructive inflammatory or reactive features clearly produced by or associated with cell-mediated or antibody-driven reactions of the patient against his own tissues. After an exhaustive search which has stretched back in time for at least the last five decades, we seem to understand how the immune system works better than previously.

Studies of serum C-reactive protein in systemic lupus erythematosus.

Objective: To examine the relationship of serum C-reactive protein (CRP) levels to other indicators of disease activity during the course of systemic lupus erythematosus (SLE).

Methods: In 124 patients serum CRP was measured retrospectively by ELISA and in some instances by radial immunodiffusion. Serum CRP levels were compared to laboratory, clinical, and radiographic assessments of disease activity.

Antibodies to microtubule-associated protein 2 in patients with neuropsychiatric systemic lupus erythematosus.

Objective: Microtubule-associated protein 2 (MAP-2), a cellular protein restricted to neurons, is important in the control of cytoskeletal integrity and other neuronal functions. We undertook this study to examine the presence of autoantibodies to MAP-2 in neuropsychiatric systemic lupus erythematosus (NPSLE).

Methods: Sera from 100 patients with SLE, 74 patients with other neurologic disorders and injuries (including cerebrovascular accidents, brain trauma, brain tumors, and demyelinating disorders), and 60 normal controls were examined both by enzyme immunoassays and by Western immunoblotting for autoantibodies to MAP-2.

Neuropsychiatric systemic lupus erythematosus presenting as amyotrophic lateral sclerosis.

A 61-year-old woman with a history of photosensitive dermatitis and recurrent mouth ulcers presented with progressive weakness typical of amyotrophic lateral sclerosis (ALS), and subsequently underwent extensive neurologic and rheumatologic testing. We investigated whether ALS-like motor neuron disease associated with a positive antinuclear antibody (ANA) is really ALS or rather neuropsychiatric systemic lupus erythematosus (NPSLE). On neurologic evaluation, she had prominent bulbar involvement with dysarthria and dysphagia associated with profound lingual fasciculations and a denervating pattern on electromyogram.