Dual-Tracer Parathyroid Imaging Using Joint SPECT Reconstruction.

Purpose: We assessed the lesion detection performance of the dual-tracer parathyroid SPECT imaging using the joint reconstruction method. Materials and Methods: Thirty-six noise realizations were created from SPECT projections collected from an in-house neck phantom to emulate 99mTc-pertechnetate/99mTc-sestamibi parathyroid SPECT datasets. Difference images representing parathyroid lesions were reconstructed using the subtraction and the joint methods whose corresponding optimal iteration was defined as the iteration which maximized the channelized Hotelling observer signal-to-noise ratio (CHO-SNR). The joint method whose initial estimate was derived from the subtraction method at optimal iteration (the joint-AltInt method) was also assessed. In a study of 36 patients, a human-observer lesion-detection study was performed using difference images from the three methods at optimal iteration and the subtraction method with four iterations. The area under the receiver operating characteristic curve (AUC) was calculated for each method. Results: In the phantom study, both the joint-AltInt method and the joint method improved SNR compared to the subtraction method at their optimal iteration by 444% and 81%, respectively. In the patient study, the joint-AltInt method yielded the highest AUC of 0.73 as compared with 0.72, 0.71, and 0.64 from the joint method, the subtraction method at optimal iteration, and the subtraction method at four iterations. At a specificity of at least 0.70, the joint-AltInt method yielded significantly higher sensitivity than the other methods (0.60 vs 0.46, 042, and 0.42; p < 0.05). Conclusions: The joint reconstruction method yielded higher lesion detectability than the conventional method and holds promise for dual-tracer parathyroid SPECT imaging.

Bone mineral density among virologically suppressed Asians older than 50 years old living with and without HIV: A cross-sectional study.

There are limited data regarding bone health in older people living with HIV (PWH), especially those of Asian ethnicity. We aimed to determine whether BMD in well-suppressed HIV-infected men and women aged ≥ 50 years are different from HIV-uninfected controls. In a cross-sectional study, BMD by dual-energy X-ray absorptiometry and calciotropic hormones were measured. A total of 481 participants were consecutively enrolled (209 HIV+ men, 88 HIV- men, 126 HIV+ women and 58 HIV- women). PWH were on average 2.5 years younger [men: 55.0 vs. 57.5 yr; women: 54.0 vs. 58.0 yr] and had lower body mass index (BMI) [men: 23.2 vs. 25.1 kg/m2; women: 23.1 vs. 24.7 kg/m2] compared to the controls. The median duration since HIV diagnosis was 19 (IQR 15-21) years in men and 18 (IQR 15-21) years in women. Three-quarters of PWH had been treated with tenofovir disoproxil fumarate-containing antiretroviral therapy for a median time of 7.4 (IQR 4.5-8.9) years in men and 8.2 (IQR 6.1-10) years in women. In an unadjusted model, HIV+men had significantly lower BMD (g/cm2) at the total hip and femoral neck whereas there was a tend toward lower BMD in HIV+women. After adjusting for age, BMI, and other traditional osteoporotic risk factors, BMD of virologically suppressed older PWH did not differ from participants without HIV (P>0.1). PWH had lower serum 25(OH)D levels but this was not correlated with BMD. In conclusion, BMD in well-suppressed PWH is not different from non-HIV people, therefore, effective control of HIV infection and minimization of other traditional osteoporosis risk factors may help maintain good skeletal health and prevent premature bone loss in Asian PWH. Clinical trial registration: Clinicaltrials.gov # NCT00411983.

Antral contractility following Asian-style meal in healthy volunteers: effect of genders, menstruation, smoking status and age.

Objectives: The normal range of the frequency of antral contractions, similar to other gastric motility parameters, are different depending on the population and the test meal. We, therefore, conducted the analysis to establish the normal ranges for the frequency of antral contractions derived from dynamic antral scintigraphy (DAS) following an Asian-styled solid meal in Thai healthy volunteers. Methods: We retrospectively analyzed the data from the study on normal gastric emptying values. The dynamic scintigraphic images had been obtained in a 45 degree left anterior oblique view during the first 32 minutes following the ingestion of a 267-kcal steamed rice, a technetium-99m-labeled microwaved egg and 100 mL of water. A polynomial normalization model was used to analyze and to calculate the frequency of antral contractions. The data analysis was repeated by the same operator 1 month apart to assess reproducibility. Results: Data of 18 volunteers (10 males and 8 females) were eligible for analysis. The mean±SD of the frequencies of the antral contractions were 3.06±1.08 cycles/min on the first and 3.04±1.10 cycles/min on the second analysis. Comparison of the two analyses revealed a moderate agreement (ICC=0.632, 95% CI 0.329-0.818) without significant difference (p-value=0.942). No significant effect of gender, menstruation status, smoking or age was demonstrated in this study. Conclusion: DAS is a non-invasive technique that can measure the frequency of antral contractions. The technique is reproducible and consistent. Future study may be required to assess the effect of gender, menstruation status, smoking and age.

Patient dosimetry of 177Lu-PSMA I&T in metastatic prostate cancer treatment: the experience in Thailand.

PURPOSE: This study aimed to determine the radiation dosimetry for 177Lu-PSMA imaging and therapy (I&T) in Thai patients who were treated for metastatic prostate cancer. METHODS: Whole-body planar images acquired at immediately, 4 and 24 h after 177Lu-PSMA I&T injection (range 4.44-8.51 GBq) were collected from 12 treatment cycles of 8 prostate cancer patients. Region of interests (ROIs) were manually contoured on the whole-body, liver, spleen, urinary bladder, lacrimal glands, parotid, and submandibular glands to determine time-integrated activity (TIA) in source organs and fitted time-activity curves using mono-exponential extrapolation. The S values calculated utilizing non-uniform rational B-splines (NURBS) computational phantoms were extracted from the OLINDA/EXM v. 2.0 to calculate the absorbed dose coefficient in target organs according to the Medical Internal Radiation Dose (MIRD) scheme. The absorbed doses to bone marrow were estimated using the planar two-compartment image-based method by separating the high-uptake and low-uptake compartment. The spherical model was used to calculate the lacrimal gland absorbed doses. RESULTS: Mean absorbed dose coefficients to the kidneys, bone marrow, liver, urinary bladder, spleen, lacrimal glands, parotid, and submandibular glands were 0.81 ± 0.24, 0.02 ± 0.01, 0.13 ± 0.10, 0.27 ± 0.25, 0.16 ± 0.07, 3.62 ± 1.78, 0.21 ± 0.14, and 0.09 ± 0.07 Gy/GBq, respectively. Dose constraints for the kidneys (23 Gy) and bone marrow (2 Gy) were not reached in any patients. The absorbed dose in lacrimal glands calculated by the NURBS computational phantoms was slightly lower than the calculation based on the Cristy-Eckerman computational phantoms using OLINDA/EXM v. 1.0 by 6.37 ± 0.14%. CONCLUSION: Dosimetry results in this study suggested that 177Lu-PSMA I&T treatment with higher activities and more cycles is possible without the risk of damaging normal organs in prostate cancer patients.

Acute Effects of Red Chili, a Natural Capsaicin Receptor Agonist, on Gastric Accommodation and Upper Gastrointestinal Symptoms in Healthy Volunteers and Gastroesophageal Reflux Disease Patients.

The effects of chili on gastric accommodation (GA) in gastroesophageal reflux disease (GERD) patients have not been explored. METHODS: In total, 15 healthy volunteers (HV) and 15 pH-positive non-erosive GERD (NERD) patients underwent single-photon emission computed tomography after ingesting 2 g of chili or placebo in capsules in a randomized double-blind crossover fashion with a one-week washout period. GA was the maximal postprandial gastric volume (GV) after 250 mL of Ensure® minus the fasting GV. Upper gastrointestinal symptoms were evaluated by using a visual analog scale. RESULTS: NERD patients but not HV had significantly greater GA after chili compared to a placebo (451 ± 89 vs. 375 ± 81 mL, p < 0.05). After chili, the postprandial GVs at 10, 20, and 30 min in NERD patients were significantly greater than HV (10 min, 600 ± 73 vs. 526 ± 70 mL; 20 min, 576 ± 81 vs. 492 ± 78 mL; 30 min, 532 ± 81 vs. 466 ± 86 mL, all p < 0.05). In NERD, chili was associated with significantly less satiety, more severe abdominal burning (p < 0.05), and a trend of more severe heartburn (p = 0.06) compared to the placebo. In HV, postprandial symptoms after chili and placebo ingestion were similar (p > 0.05). CONCLUSIONS: Chili enhanced GA in NERD patients but not in HV. This suggests that the modulation of GA in NERD is abnormal and likely involves transient receptor potential vanilloid 1 (TRPV1) sensitive pathways.

The failure of glomerular filtration rate estimating equations among obese population.

BACKGROUND: Obesity is a major public health with increasing numbers of obese individuals are at risk for kidney disease. However, the validity of serum creatinine-based glomerular filtration rate (GFR) estimating equations in obese population is yet to be determined. METHODS: We evaluated the performance of the reexpressed Modification of Diet in Renal Disease (MDRD), reexpressed MDRD with Thai racial factor, Thai estimated GFR (eGFR) as well as Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations among obese patients, defined as body mass index (BMI) ≥25 kg/m2 with the reference measured GFR (mGFR) determined by 99mTc-diethylene triamine penta-acetic acid (99mTc-DTPA) plasma clearance method. Serum creatinine levels were measured using standardized enzymatic method simultaneously with GFR measurement. The statistical methods in assessing agreement for continuous data including total deviation index (TDI), concordance correlation coefficient (CCC), and coverage probability (CP) for each estimating equation were compared with the reference mGFR. Accuracy within 10% representing the percentage of estimations falling within the range of ±10% of mGFR values for all equations were also tested. RESULTS: A total of 240 Thai obese patients were finally recruited with mean BMI of 31.5 ± 5.8 kg/m2. In the total population, all eGFR equations underestimated the reference mGFR. The average TDI values were 55% indicating that 90% of the estimates falling within the range of -55 to +55% of the reference mGFR. The CP values averaged 0.23 and CCC scores ranged from 0.75 to 0.81, reflecting the low to moderate levels of agreement between each eGFR equation and the reference mGFR. The proportions of patients achieving accuracy 10% ranged from 23% for the reexpressed MDRD equation to 33% for the Thai eGFR formula. Among participants with BMI more than 35 kg/m2 (n = 48), the mean error of all equations was extremely wide and significantly higher for all equations compared with the lower BMI category. Also, the strength of agreement evaluated by TDI, CCC, and CP were low in the subset of patients with BMI ≥35 kg/m2. CONCLUSION: Estimating equations generally underestimated the reference mGFR in subjects with obesity. The overall performance of GFR estimating equations demonstrated poor concordance with the reference mGFR among individuals with high BMI levels. In certain clinical settings such as decision for dialysis initiation, the direct measurements of GFR are required to establish real renal function among obese population.

The role of serum cystatin C in estimation of renal function in survivors of critical illness.

PURPOSE: Estimating renal function by serum creatinine after critical illness is a challenging problem. However, the role of cystatin C for estimation of the renal function in survivors of critical illness is unknown. We aimed to compare the performance of serum cystatin C- and serum creatinine-based eGFR against a reference GFR using 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA) in survivors of critical illness. MATERIAL AND METHODS: Survivors of critical illness with stable hemodynamics and renal functions were recruited. Their serum creatinine and cystatin C levels were measured. eGFR were calculated by using various equations: 1)CKD-EPI SCysC; 2) Thai eGFR SCysC; 3)CKD-EPI SCr; 4)Thai eGFR SCr; 5)MDRD Caucasian SCr; 6)CKD-EPI SCr-SCysC. The 99mTc-DTPA plasma clearance was used as a standard eGFR. RESULTS: Forty-two patients were included. The bias (median percentage difference) between standard GFR and SCysC-based eGFR were 41.97% (95%CI 33.1% to 48.5%) for CKD-EPI SCysC and 31.72% (95%CI 21.1% to 34.9%) for Thai eGFR SCysC. While, the bias between standard GFR and SCr-based eGFR were -11.37 (95%CI -20.9 to 1.6) for CKD-EPI SCr, -18.30 (95%CI -26.3 to -10.6) for Thai eGFR SCr, and -27.17 (-43.7 to -19.1) for MDRD Caucasian SCr. CONCLUSION: In survivors of critical illness, we demonstrated limitations of estimating GFR by both currently available SCysC and SCr-based equations. Therefore, further studies are still needed to develop better eGFR equations.

Bone mineral density changes among people living with HIV who have started with TDF-containing regimen: A five-year prospective study.

There are limited data regarding long-term BMD changes over time among treatment-naïve people living with HIV (PLHIV) after initiating combined antiretroviral therapy (cART) in Asia. We aimed to study bone mineral density (BMD) changes among treatment-naïve PLHIV started treatment with tenofovir disoproxil fumarate (TDF)- or non-TDF-containing regimen and HIV-uninfected controls in an Asian setting. The study was a five-year prospective study. BMD at lumbar spine (LS) (L1 to L4), total hip (TH), and femoral neck (FN) were measured by dual energy X-ray absorptiometry (DEXA) scans at baseline, months 12, 24 and 60. Multivariate logistic regression models were used to explore factors associated with mean BMD ≥5% reduction after 5 years of cART. A total of 106 PLHIV (75 and 31 started TDF- and non-TDF-containing regimen, respectively) and 66 HIV-uninfected individuals were enrolled. The mean percent changes of BMD were significantly different longitudinally between TDF and non-TDF users (p<0.001 for LS, p = 0.006 for TH and p = 0.02 for FN). HIV-positive status and on TDF-containing regimen was independently associated with BMD loss ≥5% at month 60 (adjusted odds ratio [aOR] 7.0, 95% confidence interval [95%CI] 2.3-21.0, P = 0.001 for LS; aOR 4.9, 95%CI 1.7-14.3, P = 0.003 for TH and aOR 4.3, 95%CI 1.6-11.2, P = 0.003 for FN) compared to HIV-uninfected individuals. In a multivariate model for PLHIV only, TDF use (vs. non-TDF, P = 0.005) and pre-treatment CD4+ count <350 cells/mm3 (vs. ≥350 cells/mm3, P = 0.02) were independently associated with ≥5% BMD loss in TH at month 60. Treatment-naïve PLHIV initiating treatment with TDF-containing regimen have higher BMD loss in a Thai cohort. TDF use and low pre-treatment CD4 count were independently associated with BMD loss at month 60 at TH. Earlier treatment initiation and interventions to prevent bone loss could improve skeletal health among PLHIV. Clinicaltrials.gov: NCT01634607.

Antral contraction rate estimation from dynamic antral scintigraphy using Hilbert-Huang transform.

Conventional analysis of the gastric antral contraction rate (ACR) utilizes the Fourier transform (FT) which does not effectively capture the non-stationary property of dynamic antral scintigraphy (DAS). In this study, we showed that application of Hilbert-Huang transform (HHT) on DAS yielded better estimates of ACR. Specifically, the time activity curves were extracted from the DAS data of 18 healthy volunteers and subjected to FT and HHT analyses. Comparison of the mean, standard deviation (SD), and root mean square error (RMSE) of ACR estimated by both methods showed that the proposed HHT method yielded significantly smaller SD (p<0.00001), smaller relative SD (13.3% versus 53.7%) and RMSE (0.72 cpm versus 1.59 cpm). Moreover, the HHT method also achieved lower relative SD of the frequency values from the intrinsic mode functions. Overall results indicated that the HHT method outperformed the conventional FT method in estimating the ACR from DAS. We anticipate that our approach will lead to development of effective noninvasive diagnoses of gastrointestinal tract diseases using DAS.

Antiretroviral-naïve HIV-infected patients had lower bone formation markers than HIV-uninfected adults.

There are limited studies regarding bone health among people living with HIV (PLHIV) in Asia. We compared bone mineral density (BMD), serum 25-hydroxyvitamin D (25(OH)D) status and bone turnover markers (serum procollagen type1 N-terminal propeptide (P1NP), osteocalcin (OC) and C-terminal cross-linking telopeptide of type1 collagen) among 302 antiretroviral therapy (ART) naive PLHIV compared to 269 HIV-uninfected controls from Thailand. People aged ≥30 years, with and without HIV infection (free of diabetes, hypertension, and active opportunistic infection) were enrolled. BMD at the lumbar spine, total hip, and femoral neck were measured using Hologic DXA at baseline and at 5 years. We analyzed BMD, serum 25(OH)D levels, and bone turnover markers at the patients' baseline visit. PLHIV were 1.5 years younger and had lower BMI. PLHIV had higher mean serum 25(OH)D level and similar BMD to the controls. Interestingly, PLHIV had significantly lower bone formation (serum P1NP and OC), particularly those with low CD4 count. Only a few participants had low bone mass. ARV naïve middle-aged PLHIV did not have lower BMD or lower vitamin D levels compared to the controls. However, PLHIV had lower bone formation markers, particularly those with low CD4 count. This finding supports the benefit of early ART.

Preoperative parathyroid localization using joint planar imaging.

The conventional approach for preoperative parathyroid localization with the dual 99mTc-sestamibi (99mTc-MIBI) and 99mTc-pertechnetate (99mTcO4- ) scintigraphy technique obtains the differential image by subtracting images from the two scans; the former depicts both the thyroid and parathyroid glands while the latter depicts the thyroid only. In this study, we developed a novel method based on Poisson noise modeling and maximum-likelihood estimation to generate the differential image in an iterative fashion using both planar images jointly. We demonstrated improved performance of our joint method as compared with the subtraction method in both phantom and patient studies. In the phantom study, we acquired two noise-free planar datasets using 99mTc on an in-house thyroid phantom and a "lesion" bead (representing a parathyroid gland) with the same attenuation background as the thyroid phantom. These two planar datasets were combined and scaled to simulate noise-free clinical MIBI (four lesion-to-background contrast (LBC) values: 1.2, 1.3, 1.4 and 1.5), and 99mTcO4- datasets. One-hundred Poisson noise realizations were generated for each datasets. The mean and standard deviation (SD) of the lesion contrast in the differential images were computed for both the subtraction and the joint methods. We also applied both the subtraction and the joint methods to one parathyroid patient dataset. The voxel-wise mean-to-SD ratios in four hyperfunctioning parathyroid lesions were calculated. The phantom results showed that the joint method at the 50th iteration yielded a significant SD reduction compared with the subtraction method ranging from 20% to 45% (p <; 0.05). Similarly, the voxel-wise mean-to-SD ratios were substantially improved in the patient study from 0.40-1.60 (subtraction) to 2.68-3.16 (joint).

Analysis of dynamic antral scintigraphy using empirical mode decomposition.

In this work, we proposed to use the empirical mode decomposition (EMD) to analyze signals from dynamic antral scintigraphy (DAS) for antral contraction rate estimation. The proposed EMD-Fourier method analyzes a DAS time-activity curve (TAC) which is called a DAS signal by estimating the frequency from the Fourier transform of each intrinsic mode function (IMF), thus yielding multiple frequency values for each TAC as opposed to one frequency value obtained from the conventional Fourier method. Twenty-three TACs extracted from DAS data acquired on twenty-three healthy volunteers were analyzed using both the EMD-Fourier method and the Fourier method. The mean and standard deviation of frequency across all volunteers were computed. The result showed that the EMD-Fourier method provided a reduction of SD-to-mean ratio from the Fourier method ranging from 64.3% to 85.8%. The mean frequencies from the third IMF in the EMD-Fourier method and from the Fourier method were 2.76 and 3.44 cycles per minute were close to a widely-used normal antral contraction rate (3.0 cycles per minute), while the EMD-Fourier method yielded significant SD reduction (from 4.77 to 0.57: p <; 0.0001). Moreover, it was found that the first IMF yielded a frequency estimate of 11.26 ± 2.2 cycles per minute, while the second IMF yielded a frequency estimate of 4.3 ± 1.3 cycles per minute, which are similar to the contraction rates of the duodenum and the large intestine, respectively.

Low bone mineral density and the severity of cholestasis in biliary atresia.

AIM: To investigate the prevalence of osteopenia and osteoporosis in postoperative biliary atresia (BA) children and the association of bone mineral density (BMD) and biochemical parameters in postKasai BA subjects. METHODS: A total of 70 patients with postKasai BA were enrolled in this prospective study. The patients were classified into two groups according to their jaundice status. BMD of the lumbar spine was analyzed using dual energy X-ray absorptiometry. RESULTS: The prevalence of low bone mass (osteopenia and osteoporosis) in BA patients were 51.4% (36 out of 70). Ten patients (35.7%) in the jaundice group and 8 patients (19.0%) in the non-jaundice group had osteopenia. Sixteen patients (57.1%) in the jaundice group and 2 patients (4.8%) in the no jaundice group had osteoporosis. In addition, lumbar spine BMD Z-score was substantially lower in the jaundice BA patients compared with non-jaundice patients. BA subjects with persistent jaundice had significantly lower serum 25-hydroxyvitamin D than those without jaundice. Further analysis revealed that lumbar spine BMD was correlated with age (r = 0.774, P < 0.001), serum albumin (r = 0.333, P = 0.005), total bilirubin (r = -0.476, P < 0.001), aspartate aminotransferase (r = -0.583, P < 0.001), alanine aminotransferase (r = -0.428, P < 0.001), and alkaline phosphatase(r = -0.456, P < 0.001). CONCLUSION: Low BMD was associated with biochemical parameters reflecting the severity of cholestasis in postKasai BA patients.

Increased serum sclerostin in postoperative biliary atresia.

BACKGROUND: We determined the relationship between serum sclerostin and disease severity of biliary atresia (BA). METHODS: Seventy postoperative BA patients and 35 controls were recruited. Serum sclerostin, C-terminal telopeptide of type I collagen (CTX), and osteocalcin were analyzed using ELISA. Bone mineral density (BMD) of the lumbar spine was measured by dual energy X-ray absorptiometry. RESULTS: BA patients had significantly higher serum sclerostin than controls. Serum sclerostin was markedly elevated in jaundice patients compared with jaundice-free patients. Serum osteocalcin was not different, whereas serum CTX was greater in BA patients than controls. BMD of jaundice patients was significantly lower than jaundice-free patients. Additionally, serum sclerostin was correlated with biochemical parameters and BMD in BA. CONCLUSION: Increased sclerostin levels were associated with liver dysfunction and the severity of BA, suggesting that sclerostin may reflect the deterioration of hepatic function and the outcome in postoperative BA.

Normal Solid Gastric Emptying Values Measured by Scintigraphy Using Asian-style Meal:A Multicenter Study in Healthy Volunteers.

BACKGROUND/AIMS: To report gastric emptying scintigraphy, normal values should be established for a specific protocol. The aim of this study was to provide normal gastric emptying values and determine factors affecting gastric emptying using Asian rice-based meal in healthy volunteers. METHODS: One hundred and ninety-two healthy volunteers were included at 7 tertiary care centers across Thailand. Gastric emptying scintigraphy was acquired in 45 degree left anterior oblique view immediately after ingestion of a 267 kcal steamed-rice with technetium-99m labeled-microwaved egg meal with 100 mL water for up to 4 hours. RESULTS: One hundred and eighty-nine volunteers (99 females, age 43 ± 14 years) completed the study. The medians (5-95th percentiles) of lag time, gastric emptying half time (GE T1/2) and percent gastric retentions at 2 and 4 hours for all volunteers were 18.6 (0.5-39.1) minutes, 68.7 (45.1-107.8) minutes, 16.3% (2.7-49.8%) and 1.1% (0.2-8.8%), respectively. Female volunteers had significantly slower gastric emptying compared to male (GE T1/2, 74 [48-115] minutes vs. 63 (41-96) minutes; P < 0.05). Female volunteers who were in luteal phase of menstrual cycle had significantly slower gastric emptying compared to those in follicular phase or menopausal status (GE T1/2, 85 [66-102] mintes vs. 69 [50-120] minutes or 72 [47-109] minutes, P < 0.05). All of smoking volunteers were male. Smoker male volunteers had significantly faster gastric emptying compared to non-smoker males (GE T1/2, 56 [44-80] minutes vs. 67 [44-100] minutes, P < 0.05). Age, body mass index and alcohol consumption habits did not affect gastric emptying values. CONCLUSIONS: A steamed-rice with microwaved egg meal was well tolerated by healthy volunteers. Gender, menstrual status and smoking status were found to affect solid gastric emptying.

Preliminary study of renal hemodynamic alteration in early childhood diabetes mellitus.

Renal hemodynamic study was performed in eight patients associated with type 1, early childhood diabetes mellitus (DM) and seven patients associated with type 2, early childhood DM. The results in both types of DM revealed a significant reduction in peritubular capillary flow and a high value of glomerular filtration rate (GFR) in the presence of reduced renal perfusion characteristic of glomerular hyperfiltration. These findings imply that renal ischemia has already developed in both types of early stage childhood DM and GFR is overestimated in DM, which may mislead to improper interpretation of renal function.

Osteoporosis in different age-groups and various body mass index (BMI) ranges in women undergoing bone mass measurement at King Chulalongkorn Memorial Hospital.

OBJECTIVE: To determine percentage of osteoporosis at femoral neck and lumbar spine (L1-L4) in women with different age group and various BMI ranges. MATERIAL AND METHOD: The present study was conducted in 4528 women of > or =40 years who underwent first BMD measurement at King Chulalongkorn Memorial Hospital between 2000 and 2010. Bone mineral density (BMD) of femoral neck (nondominant side) and lumbar spine (Li-L4) was measure by Dual-energy x-ray Absorptiometer (DXA). The percentage of osteoporosis was determined by WHO cutoff value using Thai nationwide reference database. RESULTS: The percentages of osteoporosis at femoral neck (FN) in age group of 40 to 49, 50 to 59, 60 to 69, and > or =70 years were 6.2%, 7.4%, 24.4%, and 51.8% respectively The corresponding figures for lumbar spine (LS) were 3.4%, 5.6%, 12.7%, and 20.9% respectively. The percentage of osteoporosis seems to increase strikingly after 60 years at both sites. The percentage of osteoporosis at FN in underweight, normal weight, overweight and obesity were 52.1%, 20.3%, 15.7%, and 9.4% respectively. The corresponding figures for LS were 22.8%, 12%, 4.8%, and 5.9% respectively. Over 30% of women of age > or =60 years with BMI of less than 23 kg/m2 had osteoporosis by the studied criteria. CONCLUSION: The percentage of osteoporosis seemed to be increasing with age and declining with BMI. Using the WHO cutoff value and Thai reference database, the percentage of femoral neck osteoporosis appeared to be higher than the lumbar spine. In the present study, the authors found that women of > or =60 years with BMI of less than 23 kg/m2 posed a substantial percentage of osteoporosis.

Prevalence and risk factors of low bone mineral density among perinatally HIV-infected Thai adolescents receiving antiretroviral therapy.

BACKGROUND: Low bone mineral density (BMD) has been reported among 10%-54% of HIV-infected adolescents in developed countries. We studied the prevalence and predictors of low BMD among HIV-infected Thai adolescents receiving antiretroviral therapy. METHODS: A cross-sectional study of lumbar spine (L2-L4) BMD as measured by dual-energy X-ray absorptiometry in Thai HIV-infected adolescents aged 12-20 years was performed. The BMD Z score was analyzed using age-matched healthy Thai children as a reference. Serum 25-hydroxyvitamin D was performed. Osteopenia was defined as BMD Z score ≤ -2. RESULTS: From October 2010 to February 2011, 101 adolescents, 50% male, with a median age of 14.3 (range: 13.0-15.7) years were enrolled. The median [interquartile range (IQR)] current CD4 T-cell count was 646 (506-796) cells per cubic millimeter and 90% had plasma HIV-1 RNA <50 copies per milliliter. The mean BMD among HIV-infected adolescents and controls were 0.855 and 0.980 g/cm (P < 0.001). The median (IQR) L2-L4 spine BMD Z score was -1.0 (-1.9 to -0.1), of which 24% had BMD Z score ≤ -2.0. The median (IQR) of 25-hydroxyvitamin D level was 24.8 (20.0-31.4) ng/mL, of which 25% had vitamin D level < 20 ng/mL. In multivariate analysis, the height for age Z score < -1.5 (adjusted odds ratio: 6.2; 95% confidence interval: 2.2 to 17.7) and history of World Health Organization clinical stage 4 before antiretroviral therapy (adjusted odds ratio: 3.7; 95% confidence interval: 1.3 to 10.7) were significantly associated with osteopenia. CONCLUSION: One fourth of HIV-infected Thai adolescents have osteopenia. Children with history of advanced-staging or having low height for age are at risk of osteopenia. Preventive measures to prevent osteopenia should be incorporated in routine care for these adolescents.

Comparisons between validated estimated glomerular filtration rate equations and isotopic glomerular filtration rate in HIV patients.

OBJECTIVE: Understanding how best to measure renal function in HIV-infected patients is critical because estimated glomerular filtration rate (eGFR) in HIV-infected patients can be affected by ethnicity and body composition. We validated the available eGFR equations and compared them to the plasma Tc-diethylenetriaminepentaacetic acid (Tc-DTPA) clearance in HIV-infected patients. DESIGN: Test of diagnostic accuracy. METHODS: One hundred and ninety-six HIV-infected patients underwent measuring of Tc-DTPA plasma clearance, five creatinine-based eGFR equations, cystatin-C GFR, and 24-h urine creatinine clearance (CrCl). RESULTS: Mean (SD) Tc-DTPA GFR was 117.7 ± 29.2 ml/min per 1.73 m. The re-expressed Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI), re-expressed MDRD formula with Thai racial correction factor, Thai eGFR equation, Cockcroft-Gault equation, cystatin-C GFR, and 24-h urine CrCl underestimated the reference GFR. The bias estimated by the mean of differences (SD) for the re-expressed MDRD equation, CKD-EPI, re-expressed MDRD formula with Thai racial correction factor, Thai eGFR, Cockcroft-Gault equation, cystatin-C, and 24-h urine CrCl can be expressed as 18.9 ± 27.3, 11.1 ± 25.5, 6.2 ± 28.8, 15.4 ± 27.0, 30.4 ± 28.0, 3.2 + 36.1, and 5.0 ± 12.1 ml/min per 1.73 m, respectively. CONCLUSION: The available eGFR equations underestimated GFR in HIV-infected adults. However, the eGFR by cystatin-C GFR was the most precise and accurate. Among creatinine-based eGFR equations, re-expressed MDRD formula with Thai racial correction factor was the most precise and accurate. The racial factor for each ethnicity is important and the existing eGFR equation should be validated before using it in the HIV population.