Prevalence of low bone mass among adolescents with nontransfusion‐dependent hemoglobin E/β‐thalassemia and its relationship with anemia severity

1 Background

Low bone mass is common among adolescents with transfusion‐dependent β‐thalassemia despite adequate transfusion and iron chelation. However, there are few reports regarding bone mineral density (BMD) among adolescents with nontransfusion‐dependent thalassemia (NTDT). Indeed, only BMD data in patients with nontransfusion‐dependent (NTD) β‐thalassemia intermedia have been reported. No previous study has investigated BMD among adolescents with NTD hemoglobin (Hb) E/β‐thalassemia.

2 Objective

To determine the prevalence of low bone mass among adolescents with NTD Hb E/β‐thalassemia and factors relating to low bone mass.

3 Methods

We investigated BMD of lumbar spine (L2–L4; BMDLS) and total body (BMDTB), as measured by dual‐energy X‐ray absorptiometry, in 22 adolescents (aged 13.2–20 years) with NTD Hb E/β‐thalassemia.

4 Results

Low bone mass was found to be 18.2% and 22.7% at the lumbar spine (BMDLS Z‐score adjusted for bone age and height age) and 13.6% and 9.1% at the total body (BMDTB Z‐score adjusted for bone age and height age). Patients with mean Hb level <8 g/dl were more likely to have low bone mass (BMDLS and BMDTB Z‐scores adjusted for bone age) compared to those with Hb level ≥ 8 g/dl. Mean Hb level correlated with BMDLS and BMDTB Z‐scores adjusted for bone age.

5 Conclusion

We demonstrated that a low Hb level was associated with low bone mass among adolescents with NTD Hb E/β‐thalassemia. A significant proportion of low bone mass among these patients highlights the importance of appropriate management, including red cell transfusion, vitamin D and calcium supplementation for improved long‐term bone health.     

A pilot study of maternal exposure to organophosphate pesticides and newborn neurodevelopment in Thailand

The objective of this study was to evaluate whether prenatal exposures to organophosphate (OP) pesticides from maternal agricultural use are associated with neonatal neurobehavioral effects. A pilot study conducted in three provinces in Thailand measured maternal urinary metabolites of OP pesticides in pregnant women at 7 months gestation and at birth. Within 3 days of birth, 82 newborns underwent neurobehavioral testing using the Brazelton Neonatal Behavioral Assessment Scale (NBAS). Comparison of the NBAS test results with maternal OP metabolite levels found the neonates NBAS Habituation cluster score increased with maternal dimethylphosphate (DMP) levels (p = 0.04) while the Range of State score increased with total diethylphosphate (DEP) levels (p = 0.01). The Number of Abnormal Reflexes in the neonate also increased as maternal urinary total DEP levels increased (p = 0.06). These preliminary findings suggest that pre-natal exposures to OP pesticides can impact newborn neurodevelopment and support the need for a longitudinal evaluation of childhood neurodevelopment in relation to pesticide exposures in Thailand.     

Genetic structure and gene flow among Aedes aegypti (Diptera: Culicidae) populations from central Thailand

Isozymes from five wild-caught populations of Aedes aegypti (L.) were compared using starch gel electrophoresis to estimate rates of gene flow between and among geographically close mosquito populations. Ae. aegypti were collected from five different locations in Bangkok, Thailand. One collection was obtained from central Bangkok (Huai-Khwang); the other four samples were obtained from surrounding areas (Districts Latkrabang, Ratburana, Laksi, and Bangkok Noi). Based on 24 loci (17 enzyme systems), only minor genetic differentiation was observed between all five populations. The highest percentage of polymorphic loci (34.3) was observed from the central Bangkok population; the least percentage of polymorphism (20.0) was seen from Laksi (north Bangkok). This study indicates that a large effective migration rate exists among all five populations. No fixed genetic differences were detected.     

Progression and resolution of acute focal bacterial nephritis

It is crucial that nephrologists correctly identify acute focal bacterial nephritis, as timely and adequate treatment with appropriate antibiotics can prevent unnecessary investigations, invasive surgical procedures, and renal complications such as renal abscess or renal scar. An urgent kidney ultrasonography should be performed if there is a delayed response to appropriate antibiotic treatment in patients with urinary tract infection. Serial kidney ultrasonography plays a significant role in confirming the diagnosis and monitoring the progression of acute focal bacterial nephritis. We presented a patient with acute focal bacterial nephritis and showed that a serial kidney ultrasonography could prevent the use of invasive investigations and inappropriate surgical procedures.     

In vitro activity of fosfomycin-gentamicin, fosfomycin-ceftazidime, fosfomycin-imipenem and ceftazidime-gentamicin combinations against ceftazidime-resistant Pseudomonas aeruginosa

The effects of antimicrobial combinations against ceftazidime-resistant Pseudomonas aeruginosa strains isolated from hospitalized patients were investigated. Using the checkerboard titration method, combination of fosfomycin-gentamicin, fosfomycin-ceftazidime, fosfomycin-imipenem and ceftazidime-gentamicin was synergistic against 4, 11, 38 and 39% of 22, 18, 29 and 18 strains tested respectively and additive effect of the combinations against the strains tested was 41, 33, 14 and 44%, respectively. Antagonistic effects against the isolates were noted when fosfomycin was combined with gentamicin (27%), ceftazidime (22%) and imipenem (7%). No antagonistic effect was observed in the ceftazidime-gentamicin combination.     

Ergocalciferol decreases erythropoietin resistance in children with chronic kidney disease stage 5

Background

Vitamin D insufficiency is related to erythropoietin resistance in chronic kidney disease (CKD). This study was conducted to evaluate the effect of ergocalciferol on the dose of erythrocyte-stimulating agent (ESA) administered to children with CKD stage 5 and vitamin D insufficiency.

Methods

Twenty patients aged <18 years with CKD stages 5 or 5D and vitamin D insufficiency were divided into two groups. During the 12-week study, ten patients received oral ergocalciferol (treatment) whereas the other ten patients did not (control). The ESA dosage was recorded monthly.

Results

There were no significant differences in demographic data, ESA dosages, and laboratory data, including corrected calcium, phosphorus, parathyroid hormone, hemoglobin, ferritin, 25-hydroxyvitamin D (25D), and transferrin saturation levels, between the two groups at baseline. At the completion of the study, serum 25D levels in the treatment group were significantly increased from baseline (p?=?0.02) and were significantly higher than the serum 25D levels in the controls (p?<?0.005). The ESA dosage in the treatment group was significantly decreased when compared to baseline (p?=?0.04).

Conclusions

Vitamin D deficiency should be routinely detected and treated. Our results show that the administration of ergocalciferol in conjunction with 1,25-dihydroxyvitamin D3 reduced the dose of ESA required to treat children with CKD stages 5 and 5D and may decrease erythropoietin resistance.     

Trabecular bone volume and osteoprotegerin expression in uremic rats given high calcium

Calcium (Ca)-containing phosphate binders have been recommended for the treatment of hyperphosphatemia in children with chronic kidney disease. To study the effects of high Ca levels on trabecular bone volume (BV) and osteoprotegerin (OPG) expression in uremic young rats, a model of marked overcorrection of secondary hyperparathyroidism was created by providing a diet of high Ca to 5/6 nephrectomized young rats (Nx-Ca) for 4 weeks. The results of chondrocyte proliferation and apoptosis, osteoclastic activity, OPG expression and BV were compared among intact rats given the control diet, intact rats given a high Ca diet and 5/6 nephrectomized rats given the control diet (Nx-Control) and the high Ca diet (Nx-Ca). Ionized Ca levels were higher and parathyroid hormone levels were lower in Nx-Ca rats than in the other groups. Final weight, final length and final tibial length of Nx-Ca rats were significantly less than those of the other groups, although the length gain did not differ among the groups. The hypertrophic zone width was markedly enlarged in Nx-Ca rats. Chondrocyte proliferation rates did not differ among the groups, whereas osteoclastic activity was decreased in Nx-Ca rats compared with the Nx-Control animals. The OPG expression and BV were increased in Nx-Ca rats compared with the Nx-Control rats. Increased BV should improve bone strength, whereas disturbance of osteoclastogenesis interferes with bone remodeling. Bone quality has yet to be determined in high Ca-fed uremic young rats.