Do we really need to pay attention to the less common crystals?

In addition to monosodium urate, calcium pyrophosphate dihydrate, and apatite crystals, a wide variety of less common crystals, artifacts, and, occasionally, some unidentified birefringent materials may be seen in synovial fluids in association with acute or chronic arthritis. These unusual crystals and their associated musculoskeletal manifestations may be confused with the more common crystals and their manifestations and sometimes may provide the clue for systemic disease because they may present with a pseudovasculitis syndrome. Important advances in understanding the molecular aspect and management of primary hyperoxalurias as well as nephropathic cystinosis provide important general information to be applied in research and in the search for a more effective management of other common crystal-induced arthritis.

Musculoskeletal manifestations of osteomalacia: report of 26 cases and literature review.

OBJECTIVE: This study was undertaken to describe the musculoskeletal manifestations in a selected population of 26 patients with biopsy-proven osteomalacia (OM) and provide a literature update. METHODS: The 26 patients with biopsy-proven OM were selected from a total number of 79 patients who underwent anterior iliac crest biopsy. The diagnosis of OM was confirmed by the presence of an osteoid volume greater than 10%, osteoid width greater than 15 microm, and delayed mineralization assessed by double-tetracycline labeling. RESULTS: OM was caused by intestinal malabsorption in 13 patients, whereas six other patients presented with hypophosphatemia of different causes. Five elderly patients presented with hypovitaminosis D, and in two patients the OM was part of renal osteodystrophy. Twenty-three patients presented with bone pain and diffuse demineralization, whereas three other patients had normal or increased bone density. Characteristic pseudofractures were seen in only seven patients. Six of the 23 patients with diffuse demineralization had an "osteoporotic-like pattern" without pseudofractures. Prominent articular manifestations were seen in seven patients, including a rheumatoid arthritis-like picture in three, osteogenic synovitis in three, and ankylosing spondylitis-like in one. Two other patients were referred to us with the diagnosis of possible metastatic bone disease attributable to polyostotic areas of increased radio nuclide uptake caused by pseudofractures. Six patients also had proximal myopathy, two elderly patients were diagnosed as having polymalgia rheumatica, and two young patients were diagnosed as having fibromyalgia. One of the patients who presented with increased bone density was misdiagnosed as possible fluorosis. CONCLUSION: OM is usually neglected when compared with other metabolic bone diseases and may present with a variety of clinical and radiographic manifestations mimicking other musculoskeletal disorders.

Practical use of bone densitometry.

Dual energy x-ray absorptiometry (DXA) is currently the best clinically available tool for diagnosing decreased bone mineral density before osteoporotic fractures occur. The recent introduction of new treatment options for osteoporosis makes accurate and early diagnosis more important than in the past. Some women lose bone at the rate of 3-5% per year in the years immediately after menopause. DXA allows early identification of individuals at risk of fracture when osteoporosis is still asymptomatic. In epidemiologic studies, each standard deviation decrease in bone mineral density at the hip is associated with an approximately 2.5-fold increase in the risk of hip fracture. The average 50-year-old woman has an approximately 40% chance of suffering one or more fragility fractures during her lifetime. DXA allows identification of individuals at risk. Insurance coverage of DXA remains variable among insurers and accepted indications are limited. This report describes some pitfalls in practical use of DXA scans, current definitions used in reporting, and provides suggestions on when DXA scans should be done.

Relapsing, localized myositis of the head and neck after a hornet sting.

Localized myositis is a result of heterogenous group of disorders associated with variable clinical, enzyme and pathologic findings. We report the case of a young woman who developed progressive, relapsing myositis of her head and neck after a hornet sting. We provide an update about the clinical spectrum of different forms of localized myositis.

The spectrum of myositis and rhabdomyolysis associated with bacterial infection.

OBJECTIVE: (1) To describe the clinical and radiographic features of 6 patients with myositis or rhabdomyolysis associated with bacterial infection. (2) To analyze the role of computed tomography (CT) in myositis associated with bacterial infection. METHODS: Review of cases treated by the authors with literature review. RESULTS: Two patients had classical pyomyositis with Staphylococcus aureus as the etiologic agent. One patient had pyomyositis with Enterobacter cloacae (the first reported to our knowledge), 2 had myositis/fasciitis (one due to Clostridium perfringens and one due to S. aureus), and one had fatal toxic rhabdomyolysis in association with C. perfringens bacteremia without evidence of gas gangrene. No patient had a completely normal CT scan of affected muscles, but CT scans in 3 patients failed to show abscesses that were subsequently discovered at surgery, while in another patient CT scanning falsely suggested a large abscess that was not present at surgery. CONCLUSION: Infection associated muscle involvement represents a spectrum of clinical manifestations that include pyomyositis, myonecrosis, fasciitis/myositis, and toxic rhabdomyolysis. Diagnosis may be delayed by the often mild clinical presentation. CT scanning alone may be unreliable in distinguishing muscle abscess from swollen muscle unless combined with CT guided needle biopsy.

Familial spondyloepiphyseal dysplasia tarda, brachydactyly, and precocious osteoarthritis associated with an arginine 75-->cysteine mutation in the procollagen type II gene in a kindred of Chiloe Islanders. I. Clinical, radiographic, and pathologic findings.

OBJECTIVE: To characterize a kindred of Chiloe Islanders with spondyloepiphyseal dysplasia tarda (SEDT), brachydactyly, precocious osteoarthritis (OA), and intraarticular calcification. METHODS: Sixteen family members underwent a complete physical examination, anthropometric measurements, radiographic studies of the spine and peripheral joints, and analysis of the type II procollagen gene (COL2A1). RESULTS: Seven family members presented with SEDT, brachydactyly, precocious OA, and periarticular calcification while 2 others had the same syndrome but without brachydactyly. The inheritance was autosomal dominant, and the disease cosegregated with a base substitution in the COL2A1 gene. CONCLUSION: The syndrome o SEDT, precocious OA, and brachydactyly in a kindred of Chiloe Islanders is associated with a point mutation in 1 allele of the COL2A1 gene. The relationship of this type of SEDT to familial calcium pyrophosphate dihydrate deposition disease and idiopathic hip dysplasia, both endemic in Chiloe Islanders, needs to be further investigated.

Reflex sympathetic dystrophy associated with antiepileptic drugs.

Reflex sympathetic dystrophy syndrome (RSDS) complicating antiepileptic drug (AED) therapy is not well acknowledged in the neurologic literature. We report 4 patients with reflex sympathetic dystrophy that occurred while they were receiving AEDs. All patients had shoulder and hand involvement, which in 2 was bilateral, and 1 had ipsilateral foot involvement. Two patients did not respond to a change in AEDs, but all improved with a course of prednisone. One patient with phenobarbital (PB)-associated RSDS relapsed on inadvertent rechallenge with secobarbital. A review of the literature showed that several other fibrosing disorders are associated with AED administration, including Dupuytren's contractures, frozen shoulder, plantar and hand nodules, and Peyronie's disease. RSD associated with AEDs is important to recognize because it may result in permanent disability if treatment is delayed.

Superoxide anion production and phagocytosis of crystals by cultured endothelial cells.

OBJECTIVE: To show that cultured human umbilical vein endothelial cells (HUVEC) are capable of phagocytizing inflammation-causing crystals and of generating superoxide anion (SOA) during phagocytosis. METHODS: The superoxide dismutase-inhibitable reduction of nitroblue tetrazolium (NBT) dye was used as a measure of SOA production. Phagocytosis was quantified by light microscopy and confirmed by transmission electron microscopy. Cytochrome C was also studied but was found to undergo spontaneous reduction by monosodium urate (MSU) without cells. RESULTS: Crystals of MSU, calcium oxalate, hydroxyapatite, and calcium pyrophosphate dihydrate (CPPD) were phagocytized and, except for the CPPD crystals, induced NBT reduction. Cholesterol and cholesterol monohydrate were neither phagocytized nor did they induce NBT reduction. CONCLUSIONS: Endothelial cells may be a significant source of oxygen radicals in crystal-associated and other arthritides.

Supravital staining of synovial fluid with Testsimplets.

We explored the use of Testsimplet (TS) in synovial fluid (SF) analysis. TS is a glass slide coated with a dry mixture of methylene blue and cresyl violet, which in contact with one drop of SF provides a stained fresh preparation. We applied the TS to the study of 159 SFs of patients with different rheumatic diseases. In those SFs of patients with crystal-associated diseases, the crystal search was performed both on unstained preparations and with TS. TS was as good as the Wright's and Papanicolaou stain in characterizing SF cells, lupus erythematosus cells, and detection of occasional bacteria. TS allowed a better visualization of Reiter's cells, cartilage fragments, synovial villi, fat droplets, and fibrin. Crystals were identified in every TS of those patients with crystal-associated diseases. TS is a rapid and reproducible method of SF supravital staining. Crystals are well preserved for simultaneous examination with compensated polarized light.