Neuropathic pain in primary knee osteoarthritis patients: correlation with physical function, quality of life, disease severity, and serum beta nerve growth factor levels

Background

Neuropathic mechanisms are thought to play a role in knee osteoarthritis (KOA) pain. Neuropathic pain questionnaires can promote diagnosis of a neuropathic component. Thus, we aimed to assess the frequency of neuropathic pain in primary KOA patients (using clinical questionnaires) and to investigate its correlation with socio-demographic factors, physical function, quality of life, disease severity, and serum beta nerve growth factor (β-NGF) levels.

Results

Seventy primary KOA patients were included. Neuropathic pain was detected in 52.9% of patients based on Douleur Neuropathique en 4 Questions (DN4) questionnaire and in 38.6% of patients based on Leeds assessment neuropathic pain symptoms and signs questionnaire (LANSS). Serum β-NGF levels were significantly higher in KOA patients than controls (P<0.0001), and in KOA patients with neuropathic pain compared with patients with non-neuropathic pain. DN4 score was positively correlated with Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain, stiffness, and physical function, and it was also negatively correlated with Osteoarthritis knee hip quality of life questionnaire (OAKHQOL) pain scores (rs=0.459, P<0.001; rs= 0.258, P= 0.031; rs= 0.307, P= 0.010; rs = −0.337, P= 0.004, respectively), while LANSS scale was positively correlated with symptom duration, WOMAC stiffness, Lequesne pain, and Lequesne index (rs= 0.260, P= 0.020; rs= 0.343, P= 0.004; rs= 0.344, P= 0.004; rs= 0.322, P= 0.007) and negatively correlated with OAKHQOL physical, OAKHQOL mental health, OAKHQOL social support, and total OAKHQOL scores (rs= −0.258, P= 0.031;rs= −0.254, P= 0.034; rs= −0.283, P= 0.018; rs= −0.261, P= 0.029 respectively).

Conclusions

Neuropathic pain symptoms are frequent in primary KOA patients. KOA patients with neuropathic pain have worse quality of life, extreme disability, and higher serum β-NGF levels. Nerve growth factor inhibitors could have a potential role for not only relieving pain in KOA patients but also improving functional disability and quality of life in these patients.

Serum interleukin-6 in systemic sclerosis and its correlation with disease parameters and cardiopulmonary involvement

OBJECTIVE

To assess serum interleukin-6 (IL-6)level in patients with systemic sclerosis (SSc) and its correlations with European Scleroderma Study Group activity score (EUSTAR), Scleroderma Assessment Questionnaire (SAQ), disability index and cardiopulmonary involvement.

METHODS

Twenty SSc patients and 10 matched healthy controls were included. Serum IL-6 was measured in patients and controls. Disease activity, status,and disability were assessed.Cardiopulmonary involvement was evaluated by pulmonary function tests (PFTs), six minute walk test, echocardiography, and high resolution computed tomography (HRCT) of chest.

RESULTS

Serum level of IL-6 was significantly higher in patients with SSc (6.3± 1.4pg/ml) versus healthy controls (3.2± 0.4pg/ml) (P=0.002). IL-6 level showed positive correlations with disease duration (r=0.49, P=0.03), EUSTAR score (r=0.64, P=0.002), Index of Respiratory Status "IRS" (r=0.46, P=0.001), Index of Musculoskeletal Status "IMSS" (r=0.45, P=0.049), Index of Vascular Status "IVS" (r=0.39, P=0.04), mean and peak of pulmonary artery pressure (r=0.44 & 0.55, P=0.02 & 0.002 respectively). Negative correlations of IL-6 level with DLCO% (r=-0.49, P=0.006),six minute walk distance (6MWD) (r=-0.52, P= 0.003) and right ventricle fraction area change (r=-0.48, P=0.03) were found, while there were strong positive correlations with HRCT-ground glass score (r=0.77, P=0.0001) and HRCT-fibrosis score (r=0.62, P=0.003).

CONCLUSION

IL-6 level is increased in patients with SSc and significantly correlates with EUSTAR score, IRS, DLCO, 6MWD, HRCT scores, and echocardiographic abnormalities of the right side of the heart. These results support the role of IL-6 in the disease activity and in the development of cardiopulmonary manifestations in SSc patients.

Ultrasonographic diagnosis of articular chondrocalcinosis

To investigate the role of high-frequency ultrasonography in the diagnosis of calcium pyrophosphate dihydrate (CPPD) calcifications, in the most commonly affected joints in CPPD disease. Sixty patients with knee effusion were included in the study. All patients underwent musculoskeletal ultrasonography (on the shoulder, elbow, wrist, and knee joints), radiological examination of the sites examined by US, and synovial fluid analysis (using polarized light microscopy). Out of 60 patients with knee effusion, ultrasonographic calcifications (knees, shoulders, and wrists) were present in 38 patients (63.3%) and out of those patients; 32 had calcification characteristic of CPPD crystals deposition (hyperechoic deposits) in the knee and wrist joints. Pattern II (punctate pattern) was the most common pattern of calcification. It was present in all patients who had wrist calcification (18 patients) and in the knee in either alone (21 patients) or in association with pattern I (hyperechoic band) and/or pattern III (hyperechoic nodular or oval deposits) (9 patients). The sensitivity of ultrasonography for the detection of calcification was 84.2% while that of plain radiography was 13.2%, the specificity of both ultrasonography and plain radiography for the detection of calcification was 100%, and ultrasonography is valuable for diagnosing articular chondrocalcinosis via the detection of calcifications within the joint cartilage and fibrocartilage. Both sensitivity and specificity are high for detecting CPPD deposits.

Asymptomatic pulmonary hypertension in systemic lupus erythematosus

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a serious and often fatal complication of systemic lupus erythematosus (SLE). Because the diagnosis of PAH often is made years after symptom onset, early diagnostic strategies are essential. Doppler echocardiography currently is considered the noninvasive screening test of choice for evaluating pulmonary hypertension.

AIM

Screening for asymptomatic pulmonary hypertension in systemic lupus erythematosus patients using Doppler echocardiography, and correlating it with inflammatory parameters of the disease.

PATIENTS AND METHODS

Doppler echocardiography was performed in 74 patients with systemic lupus erythematosus over one year (66 adult and 8 juvenile), adult SLE included 57 patients with adult-onset and 9 patients with childhood-onset. Pulmonary hypertension was diagnosed if the peak systolic pressure gradient at the tricuspid valve was more than 30 mmHg. All patients were subjected to full history taking, rheumatological examination, laboratory studies and chest x-ray.

RESULTS

In seventy four SLE patients, the pulmonary hypertension was detected in 8 patients (10.8%), 7 adult-onset SLE patients (aged from 19 to 30 years) and 1 juvenile SLE (aged 12 years). The range of pulmonary artery systolic pressure was 34-61.2 mmHg (43.19 ± 9.28). No significant differences between patients with and those without pulmonary hypertension as regard clinical features. Significantly higher frequencies of rheumatoid factor and anti-cardiolipin antibodies were found in patients with pulmonary hypertension versus those without (P = 0.02, P = 0.008 respectively). Positive rheumatoid factor and ACL were significantly associated with occurrence of PAH in SLE (P = 0.007, P = 0.006 respectively). No significant correlations were found between pulmonary artery pressure, disease duration, SLE Disease Activity Index (SLEDAI), ESR, and anti-ds DNA.

CONCLUSION

Patients with SLE have an increased risk of pulmonary arterial hypertension. Echocardiography should be used as a screening tool in patients at high risk for development of pulmonary hypertension. Positive anti-cardiolipin antibodies and rheumatoid factor were significant predictors of pulmonary hypertension in our study.

3H and 125I radioimmunoassays of haloperidol compared with fluoroimmunoassay involving antibody coupled to magnetizable solid phase

Radioimmunoassays for haloperidol are described, involving use of tritium- or 125I-labeled drug or tritium-labeled spiroperidol, and a rabbit antiserum to a drug/bovine serum albumin conjugate. The 125I-labeled drug was prepared by the Chloramine T iodination technique. A fluoroimmunoassay for haloperidol is also described in which the antiserum is coupled to magnetizable solid-phase medium, and fluorescein-labeled haloperidol is used. The assays have acceptable accuracy, precision, and reproducibility, and are specific for haloperidol and similar butyrophenones, with no significant interference from known metabolites and other drugs. Only the radioimmunoassays have sufficient sensitivity to cover the whole range of haloperidol concentrations in serum. The fluoroimmunoassay can be used to monitor high concentrations of haloperidol in 150-microL samples or the complete concentration range of 1-mL serum samples that are extracted and concentrated before assay.

3H and 125I radioimmunoassays of haloperidol compared with fluoroimmunoassay involving antibody coupled to magnetizable solid phase

Radioimmunoassays for haloperidol are described, involving use of tritium- or 125I-labeled drug or tritium-labeled spiroperidol, and a rabbit antiserum to a drug/bovine serum albumin conjugate. The 125I-labeled drug was prepared by the Chloramine T iodination technique. A fluoroimmunoassay for haloperidol is also described in which the antiserum is coupled to magnetizable solid-phase medium, and fluorescein-labeled haloperidol is used. The assays have acceptable accuracy, precision, and reproducibility, and are specific for haloperidol and similar butyrophenones, with no significant interference from known metabolites and other drugs. Only the radioimmunoassays have sufficient sensitivity to cover the whole range of haloperidol concentrations in serum. The fluoroimmunoassay can be used to monitor high concentrations of haloperidol in 150-microL samples or the complete concentration range of 1-mL serum samples that are extracted and concentrated before assay.