Validation of Diagnostic Utility of Salivary Urea in Patients with Chronic Kidney Disease in Chennai: A Cross-Sectional Study.

BACKGROUND: Serum urea levels are essential for the diagnosis of chronic kidney disease (CKD), as they are a measure of renal function. Salivary urea has been used as an alternative to serum urea in patients with CKD. AIM: To estimate serum urea levels and their correlation with salivary urea levels in order to validate the use of saliva as an alternative diagnostic tool for renal dysfunction. PATIENTS AND METHODS: Thirty healthy individuals and 150 patients with CKD (30 from each CKD stage) were recruited for the study. Serum and salivary samples were collected to estimate the urea levels, and statistical analyses were performed. RESULTS: Statistically significant (P < 0.05) differences in the mean serum and salivary urea levels were observed between the healthy and each stage of the CKD group; significance at P < 0.05 was observed within the stages of CKD as well. Correlation analysis also showed significant differences between the serum and salivary urea levels at each stage of the disease. Receiver operating characteristic analysis revealed a higher area under the curve of 0.917 at a 95% confidence interval with a salivary urea cut-off of 28.25 mg/dl (sensitivity and specificity: 88% and 84%, respectively). CONCLUSION: The variability in salivary urea levels in the early and late stages suggests the use of salivary urea in the late stages of CKD. It is suggested that salivary urea levels may be used as an alternative to serum to assess and monitor the progression of renal impairment along with other standard renal function markers.

Relationship between Insulin Resistances with Autonomic Functions in Patients with Type 2 Diabetes in South Indian Population.

Cardiovascular disease (CVD) and type 2 diabetes mellitus (T2D) are major health concerns In India. Insulin resistance (IR) itself is a risk factor for CVD. Though it is associated to sympathetic activity this relation may get altered in presence of obesity. Therefore, in the present study we measured the link of IR, with their body mass index (BMI) and the corresponding degree of alteration in various autonomic function tests in T2D patients. It was an observational study conducted in a tertiary care hospital for a period of six months. Eighty-five T2D patients visiting medicine OPD were recruited out of which 17 were normal, 31 were overweight and 31 were obese as per WHO criteria of obesity. Their glucose, insulin, insulin resistance was analyzed in fasting blood samples. Conventional autonomic function tests such as isometric hand-grip test and deep breathing test was digitally recorded. Heart rate variability was recorded as LF: HF ratio. The Rate-pressure product (RPP), the marker of myocardial work stress was calculated from systolic blood pressure and basal heart rate. E: I ratio was calculated from RR interval from ECG tracing. Insulin resistance was positively associated with increased basal heart rate. It was linked to increase LF: HF ratio even after controlling for BMI. Regression analysis showed insulin resistance to be an independent factor for sympathovagal imbalance in T2D patients. The severity of insulin resistance independently predicts degree of deterioration in sympathovagal imbalance as measured in LF: HF ratio in our study which is independent of their degree of obesity.

Dentin degradonomics - The potential role of salivary MMP-8 in dentin caries.

BACKGROUND: Dentin caries involves dissolution of minerals which eventually leads to degradation of organic matrix. This degradation which was thought to be by bacterial proteases is now considered to be orchestrated by endogenous collagenases such as Matrix Metalloproteinases (MMPs). This paper aims to estimate the salivary levels of MMP-8 in dental caries and also to asses the various risk factors that contribute to the formation of dental caries. MATERIAL AND METHODS: A random sample of 75 adults aged 18-35 were included and categorized based on the number of caries lesions (MCL). Standard clinical examinations were performed, and stimulated saliva was collected and analyzed for concentrations of MMP-8 using enzyme-linked immunosorbent assay. Caries risk factors were assessed using a chair-side kit. Correlation of MMP-8 in varying MCL using Spearman's correlation was done. Multiple linear regression analysis was done to asses the relationship between various caries risk factors with MMP-8 and MCL as dependent variable. RESULTS: The study results showed a statistically significant higher concentration of MMP-8 in carious group (MCL 1-2) and MCL ≥3 compared to non-carious group. On correlating, the levels of MMP-8 were seen to be higher in MCL ≥3 than in MCL = 0 and MCL 1-2. The mean MMP-8 of controls, MCL 1-2, and MCL ≥3 were 131.34ng/ml, 230.14ng/ml, and 391.91ng/ml respectively. Multiple linear regression analysis with MMP-8 as the dependent variable revealed caries, buffer capacity and S. mutans count as significant variables. Using MCL as the dependent variable the only significant variable was MMP-8 levels. CONCLUSIONS: The study suggests that subjects with caries have elevated MMP-8 levels compared with subjects with no carious lesions. There is also a positive correlation between the number of carious lesions and MMP-8 levels suggesting that MMP-8 plays an important role in the degradation of dentin and causes progression of caries. Key words:Caries, Dentin, Enzyme-linked Immunosorbent Assay, MMP-8.

Diagnostic Utility of Cytology in Assessment of Ploidy Status in Potentially Malignant Oral Disorders.

INTRODUCTION: Oral leukoplakia, the most common potentially malignant oral disorder (PMOD) may progress to oral squamous cell carcinoma (OSCC). Although, the current standard of care for assessing its malignant potential remains histological examination and assessing the severity of dysplasia, DNA ploidy analysis has been suggested as a surrogate marker to predict the behaviour of PMODs. OBJECTIVES: To detect aneuploidy and to correlate ploidy status with different grades of dysplasia in both tissue and cytology samples to predict the behaviour of these potentially malignant disorders and to assess the diagnostic utility of cytology samples for ploidy analysis. METHODOLOGY: After obtaining ethical clearance and consent, tissue and cytology samples of leukoplakia were collected and grouped based on the dysplastic findings into low-risk (n=20) and high-risk (n=20). DNA ploidy analysis was done using high resolution flow cytometry and its diagnostic utility was assessed. RESULTS: Diagnostic utility was expressed in terms of sensitivity, specificity, PPV and NPV. On comparing the ploidy status of individual cases between tissue and cytology samples, cytology was able to accurately determine the ploidy status in majority of the cases. In the low-risk group, cytology had a sensitivity and specificity of 100% and a PPV and NPV of 100% with an overall diagnostic accuracy of 100%. Among the high-risk group, cytology had a sensitivity of 80% and specificity of 100% with a PPV of 100% and NPV of 83.33% and had an overall diagnostic accuracy of 90%. Combining both groups together, it had a sensitivity of 85.71% and specificity of 100% with a PPV of 100% and NPV of 92.31% and had an overall diagnostic accuracy of 94.74%. CONCLUSION: Overall, this study showed a positive correlation between cytology and tissue samples and ploidy and grade of dysplasia and cytology proved to be a simple and efficient with a reasonable diagnostic value.

Evaluation and Comparison of Vascular Endothelial Growth Factor Expression between Ameloblastoma and Keratocystic Odontogenic Tumor.

BACKGROUND: Odontogenic keratocyst (OKC) is a developmental odontogenic cyst with an aggressive clinical behavior suggesting a change in its terminology from a cyst to a tumor and has now been renamed as keratocystic odontogenic tumor (KCOT). The purpose of this study was to assess and compare angiogenesis in ameloblastoma and OKC. MATERIALS AND METHODS: Angiogenesis was assessed by studying the immunohistochemical expression of vascular endothelial growth factor (VEGF). The study samples included 15 ameloblastomas and 15 KCOTs. The immunoreactivity was statistically evaluated using Mann-Whitney U-test. RESULTS: VEGF expression was higher in ameloblastoma than KCOTs. However, a non-significant difference of VEGF expression was noted between ameloblastoma and KCOTs (P = 0.345). CONCLUSION: The results suggest that tumor angiogenesis may play a significant role in aggressive biologic behavior of KCOT. Thus, angiogenesis could be a potent target for developing anatiangiogenic therapeutic strategies.