Encephalopathy with upper body hypertonia and myoclonus in patient with systemic lupus erythematosus and anti-CASPR2.

Systemic lupus erythematosus (SLE) may involve the nervous system but there are no specific biomarkers of neuroSLE. Limbic encephalitis has been rarely associated with SLE. We present a case of a 22-year-old black woman where typical SLE psychosis evolved to an encephalopathy with atypical features, normal MRI, electroencephalogram slowing and frontal and occipito-temporal hypometabolism on fluorodeoxyglucose positron emission tomography (FDG PET).Memory deficits, bizarre behaviour, psychosis, neuromyotonia and movement disorders have been described in autoimmune central nervous system disorders and associated with specific antibodies. Brain MRI may be normal and cortical brain hypometabolism on FDG PET scans has been reported. We have not found any report of limbic encephalitis or other SLE neurological manifestation associated to positive titres of anti-CASPR2 antibodies and this may warrant systematic investigation. In the rare cases of limbic encephalitis associated with SLE no specific antibodies were documented. Anti-CASPR2 antibodies have been associated not only with limbic encephalitis but also with neuromyotonia and Morvan syndrome. Although our patient had a specific pattern of tone abnormalities with an impressive cervical and upper limb hypertonicity and flaccid lower limbs, no myotonic discharges were found. We did not find any association between myoclonus and anti-CASPR2 antibodies. We cannot exclude that a non determined autoantibody could have played a role; however, clinical and FDG PET improvement supports an antibody-mediated injury, in this case of neuroSLE.

Platelet Rich Plasma: What should the rheumatologist expect?

In the last few decades, thousands of patients have benefited from platelet rich plasma (PRP) therapies, emerging as a safe alternative in many different medical fields. Current evidence suggests that PRP may be of benefit over standard treatment in osteoarthritis patients and, in the musculoskeletal soft tissue injuries potential healing effects are waiting to be confirmed with robust evidence. Finally, in systemic rheumatic diseases PRP seems to have a role to play in the treatment of extra-articular symptoms.

A quantitative comparison of a bone remodeling model with dual-energy X-ray absorptiometry and analysis of the inter-individual biological variability of femoral neck T-score.

The development of consistent procedures with the inclusion of patient-specific data is essential in the computational modeling of biological processes, in order to achieve clinical relevant data. In this work, these issues are addressed with the development of a methodology that combines the gold standard technique for bone mineral density measurement and osteoporosis diagnosis, Dual energy X-ray absorptiometry (DXA), with a computational model for bone remodeling simulation. The DXA results were divided in three samples constituted from proximal femur DXA exams of patients in different stages of bone mineral density (normal, osteopenia and osteoporosis). These results were quantitatively compared with computational model results. A correlation study was performed between femoral neck T-score and a parameter from the model to ascertain the hypothesis of adjusting the model accordingly to biological variables. The results evidenced the predictive ability of the computational model in the estimation of femoral neck bone mineral content (BMC), with a maximum relative error of 3.92%. On the other hand, a strong correlation (R=-0.862) was found between the variables in study and a mathematical relationship was obtained to estimate the range of values for a model parameter that leads to biological relevant results. The methodology developed and the results obtained represent a solid and reliable basis to further studies on bone quality, ensuring the validity of the computational model in the simulation of bone remodeling process.

Evaluation of bone mechanical strenght and fracture risk assessment (Frax) in patients with hip joint replacement surgery.

BACKGROUND: Fracture risk assessment tools are useful to calculate the long term probability of osteoporotic fracture. However, how it reflects bone quality is unknown. The aim of this study was to correlate the WHO clinical fracture risk assessment tool, FRAX, with bone mechanical properties. METHODS: Six patients submitted to hip replacement surgery, either due to osteoporotic fractures or to osteoarthritis, were evaluated. Bone samples were collected and the mechanical properties assessed by compression tests. Patients' data regarding the presence of clinical risk factors for fracture were registered. Laboratorial assessment of bone metabolic parameters and a dual X-ray absorptiometry(DXA) were done. RESULTS: Analysis of the load-displacement curves showed that patients with fragility fractures (n=4) had low values of elastic modulus, yield load and energy absorbed until yield point. Osteoarthritis patients tend to have a better biomechanical performance.Femoral neck DXA scan was also performed in 3 patients. Fragility fracture patients had a lower bone mineral density than the patients with osteoarthritis. FRAX algorithm was applied and a positive relation was found between FRAX results and biomechanical parameters. Blood bone metabolic markers were within the normal range for all the subjects. CONCLUSIONS: The worse mechanical properties observed in the fragility fracture patients were related to high probability of fracture given by FRAX. These observations, in a very small sample, need further confirmation. However, they suggest that the fracture risk assessment tool, FRAX, may reflect the current mechanical bone behavior of the patient.

Factors influencing calcaneus quantitative ultrasound measurements in an urban population.

OBJECTIVE: To estimate the effect of demographic, social, behavioural and anthropometric factors on quantitative ultrasound (QUS) parameters in an urban population. METHODS: Cross-sectional evaluation of consecutive subjects selected as part of the EPIPorto study, Portugal. Information was obtained on demographic, social, clinical and behavioural characteristics using a standard protocol. Calcaneus QUS parameters (Broadband Ultrasound Attenuation-BUA, and Speed of Sound-SOS) were obtained for men and women, stratified by age group. Comparisons according to exposure levels were made using the Kruskal-Wallis test and the multivariate effect on QUS parameters was estimated by linear regression. RESULTS: 1482 consecutive subjects (1010 females and 472 males), aged from 18 to 92 years. Higher levels of QUS parameters were found in the younger groups and progressive decrease with age were reported. Men showed higher values as compared to women in all parameters and differences between them increased with age. Differences were significant for BUA after the age of 39 and for SOS after the age of 59. In women, the multivariate model showed that age, body mass index (BMI) and smoking status were independent predictors of BUA and SOS. In men, age, BMI and calcium intake were significantly associated with BUA and SOS. CONCLUSION: The reference values in our Portuguese population are similar to others obtained in Southern European countries. In the Portuguese population, QUS parameters have age, sex and BMI as its major determinants. In addition, BUA and SOS may reflect specific bone characteristics influenced by a different set of independent determinants.

Cross-sectional study of 50 patients with calcium pyrophosphate dihydrate crystal arthropathy.

Calcium pyrophosphate dihydrate crystal arthropathy (CPPA) is a well known but heterogeneous disease with a variable presentation and course. We present a cross-sectional study undertaken in a Portuguese rheumatology unit with the aim of analysing clinical and radiological patterns of CPPA in our population. The study population included 50 patients, 34 (68%) women and 16 (32%) men. The mean age was 69.8 +/- 8.8 years. The onset features were acute arthritis in 19 (38%) patients and chronic joint complaints in 26 (52%); five (10%) patients were asymptomatic at the time of diagnosis, which was based only on radiological findings. The diagnosis was established in 37 (74%) cases by clinical and radiographic features, in eight (16%) by clinical, X-ray and synovial fluid analysis, and in five (10%) by clinical features and fluid analysis. The disease course was characterised by acute episodic arthritis in 16 (32%) patients and by persistent symptoms (with or without synovitis) in 34 (68%). The pattern of CPPA in 20 (40%) patients was pseudo-osteoarthritis with synovitis, pseudo-osteoarthritis without synovitis in nine (18%), pseudogout in nine (18%), monoarthropathy in eight (16%) and pseudorheumatoid arthritis in four (8%). The phosphocalcium balance was altered in nine (18%) cases: six patients had hypercalciuria two hyperphosphaturia, two hypocalciuria, one hypophosphaturia and one hypercalcemia. Five patients had abnormal thyroid hormone levels, but only one presented with clinical hypothyroidism. Four patients showed increased parathormone levels, but only one presented with clinical hyperparathyroidism. Radiographic findings showed that 43 (86%) patients had meniscus calcifications, 20 (40%) radiocarpal and 16 (32%) calcification of the symphysis pubis. The study confirms the clinical variability of the disease in a population of Portuguese patients. The knee meniscus calcifications were the most sensitive single finding for establishing the diagnosis of CPPA. Almost all our patients had sporadic idiopathic CPPA without associated pathological conditions.

[Osteoporosis in adult men]. / A osteoporose no homem adulto.

Osteoporosis in men, despite being a less important public health problem than osteoporosis in women, should not be neglected as it has many deleterious effects as well as social and economic costs. Finding the cause of osteoporosis is more complex in men than in women, and prevention should be based on an early evaluation of the various possible risk factors and on taking up measures that tend to maximise the peak bone mass. Further studies need to be carried out in order to establish the differences and similarities that characterise this phenomenon when considering different sexes.