A long-term study of bone mineral density in patients with phenylketonuria under diet therapy.

INTRODUCTION: Dietary control of classic phenylketonuria (PKU) needs restriction of natural proteins; adequate protein intake is achieved by adding low phenylalanine (phe) formulae. The adequacy of this diet for normal bone mineralization had not been sufficiently evaluated. Our aim was to evaluate and follow up bone mineral density (BMD) in children and adolescents with PKU within a 2-year time interval to assess the adequacy of a phenylalanine restricted diet for bone mineralization and to search for a possible relationship between BMD, dietary control and blood phenylalanine (phe) concentrations. MATERIAL AND METHODS: Thirty-two patients with classic PKU (3-19 years) were evaluated for their bone mineral status using dual energy X-ray absorptiometry (DEXA) both at the beginning (baseline) and the end (follow-up) of the study. RESULTS: Low BMD was detected in 31.25% at the start and in 6.25% of patients after 2 years follows-up. No relationship was found between BMD and the duration of diet compliance and phe level as well. CONCLUSIONS: In this study the low BMD detected in our patients was both at baseline and follow-up independent of diet restriction. A yearly DEXA would be highly beneficial for early detection and treatment, thus preventing osteoporosis and decreasing the risk of fractures. We also suggest the importance of searching for new emerging therapies such as enzyme substitution or gene therapy as low protein diet compliance was not enough to maintain normal bone mineral density.

Frequency of Firmicutes and Bacteroidetes in gut microbiota in obese and normal weight Egyptian children and adults.

INTRODUCTION: Obesity and associated metabolic disorders are a worldwide epidemic. Recent evidence suggests that the microbial community in the human intestine may play an important role in the pathogenesis of obesity. The aim of this study was to assess the differences in the composition of the intestinal microbiota between obese and normal weight Egyptian children and adults. MATERIAL AND METHODS: The study included 79 subjects among whom 51 were obese (23 children and 28 adults), and 28 were subjects of normal weight (17 children and 11 adults). Faecal samples were collected from all subjects. Total DNA was extracted from collected stool samples and submitted to conventional PCR for detection of Firmicutes and Bacteroidetes. All the studied group was subjected to clinical and anthropometric evaluation. Laboratory assessment of fasting glucose, high-sensitivity C-reactive protein (hsCRP) and lipid profile was performed. RESULTS: The proportions of the phyla Firmicutes and Bacteroidetes were statistically significantly increased in the obese group compared to the normal weight group (p < 0.001, p = 0.003 respectively). The study also found a statistically significant positive trend for higher hsCRP in subjects with positive Firmicutes (p = 0.004). However, no associations were found between positive Bacteroidetes and hsCRP. CONCLUSIONS: The results of this study indicate that obesity in Egyptian children and adults is associated with compositional changes in faecal microbiota with increase in the phyla Firmicutes and Bacteroidetes. This could be considered when developing strategies to control obesity and its associated diseases by modifying the gut microbiota.

Avoiding the under-diagnosis of low bone mineral density in Egyptian children with chronic medical conditions affecting bone health.

INTRODUCTION: The International Society for Clinical Densitometry recommended that the lumbar spine and total body less head (TBLH) are the most accurate and reproducible skeletal sites for performing areal bone mineral density (BMD) measurements. Our objective is to evaluate the role of measurement of femoral neck BMD in avoiding the under-diagnosis of low BMD being a risk for fractures in subjects with chronic medical conditions that might affect bone health. MATERIAL AND METHODS: Subjects with chronic medical conditions that might affect bone health were studied (n = 468) and 36 healthy children were recruited as control subjects. Physical examinations, height, weight measurements and BMI were calculated. Dual-energy radiographic absorptiometry of the lumbar spine and femoral neck were measured. RESULTS: Bone mineral density z scores in both sites were significantly reduced in chronic patients, compared with control subjects. Prevalence of very low BMD z scores (-2 or more) using lumbar DXA, femoral DXA, and either of the sites were 1.38%, 3.37%, and 3.96%, respectively, while low BMD Z scores (-1 to less than -2) were 9.52%, 18.05% and 21.14% respectively. CONCLUSIONS: We identified a significant decrease in both lumbar and femoral BMDs in studied children. Sometimes femoral BMD is decreased while lumbar BMD is still within the normal range. For this reason we recommend that, when technically feasible and there is no facility to measure TBLH, all those patients should have lumbar spine and femoral neck bone mineral density measurements to avoid under-diagnosis of low BMD being a risk for fractures.