Bone mineral disorders in pediatric and adolescent renal transplant recipients.

Incomplete resolution of abnormalities of mineral metabolism associated with CRF results in the relatively high prevalence of ROD in pediatric kidney recipients. This non-randomized, cross-sectional, and analytic-descriptive study on bone density, vitamin D, and mineral metabolism was performed in 57 children and adolescents who had received a total of 60 renal allografts in Shiraz, Iran. The height and weight of the patients were measured; their serum calcium (Ca), phosphorus (P), Alk-P, PTH, 25(OH)-vitamin D(3), BUN, creatinine, and electrolyte levels were analyzed, and a complete blood count was performed. In addition, standard radiologic bone assessments, which included conventional left hand-wrist radiography and bone mineral densitometry by the DXA technique, were carried out. Special pediatric software was used for age-related interpretation of the Z-scores of BMD. SPSS(®) software (version 15) was used for statistical analyses. We studied 57 patients (27 males [47.4%]) with a mean age of 18.7 ± 4.25 (9-27) yr and a mean age at transplantation of 13.1 ± 3.46 (4.5-20) yr. They had a post-transplantation follow-up of 67.1 ± 33.8 (6-132) months, and all had well-functioning allografts at enrollment. The mean height age of the patients was 11.9 ± 1.8 (6-15.5), and the mean bone age was 15.6 ± 3.3 (7-19) yr, which corresponded to mean height-age and bone-age retardations of 5.7 ± 2.3 (0.5-10.5) and 1.22 ± 1.47 (0-7) yr, respectively. Hyperphosphatemia and hypercalcemia were each found in nine patients (15.8%), hypophosphatemia in five (8.8%), and hypocalcemia in none of the patients. Seven out of 57 patients (12.3%) had a (Ca×P) product of more than 55 mg(2)/dL(2). Hyperparathyroidism was found in 27 (47.3%) and vitamin D(3) deficiency in four (7%) of the cases. The serum level of Alk-P was higher than the age-related normal range in 20 patients (35%). Left hand-wrist radiography showed no radiologic sign of ROD in any patient. The mean BMD Z-score was -1.77 ± 1.13 (-4.2-1.1) for the lumbar spine and -1.64 ± 0.89 (-3.9 to 1.9) for the femoral neck. "Stepwise backward regression" revealed a significant inverse correlation between the serum level of PTH and the GFR of the transplanted kidney; this correlation was independent from the influence of other variables such as Ca, P, and Alk-P (p = 0.011, ß = -1.556). Bone age and height age both showed significant correlations with age at transplantation and serum levels of P (p < 0.001), but only bone age had a meaningful correlation with Alk-P (p = 0.036). The BMD Z-scores showed statistically meaningful correlations with the serum level of Alk-P, which were independent from the influence of other variables such as Ca, P, and PTH (p ≤ 0.002). Our study revealed a relatively high prevalence of bone mineral disorder in pediatric kidney recipients, which suggests the need for a routine program for periodic screening of these patients to facilitate early diagnosis of either persistent or evolving manifestations of disturbed mineral metabolism, especially ROD.

Autoimmune thyroid disease in children and adolescents with type 1 diabetes mellitus in Northwest Iran.

OBJECTIVE: To investigate the prevalence of autoimmune thyroid disease in diabetic children in Northwest Iran. METHODS: In a cross-sectional study from February 2006 to November 2007, serum levels of anti-thyroid peroxidase, and anti-thyroglobulin antibodies, and thyrotropin hormone were measured with ELISA method in 176 diabetic children (78 Male and 98 Female) at a mean age of 8.3 +/- 3.7 and mean diabetes duration of 1.6 +/- 2.5 years, who were referred to the Pediatric-Endocrinology Clinic of Tabriz University of Medical Sciences, Tabriz, Iran. RESULTS: Autoimmune thyroid disease was found in 12% of patients (8.6% female, and 3.4% male). Significant levels were found for anti-thyroid peroxidase (10.2%), anti-thyroglobulin (8%), and both antibodies (6.3%) in all patients. CONCLUSION: We concluded that autoimmune thyroid disease in Iranian children, and adolescents with type 1 diabetes has a medium prevalence rate compared with those of other countries. The disease is more common in female, and older diabetic patients.

Diagnosis of airway malacia by virtual bronchoscopy.

The study was aimed to identify the role of virtual bronchoscopy in detection of airway malacia in children. In a pre-experimental study over 3 years (from Nov. 2003 to Oct. 2006), 35 consecutive patients were presented to Tabriz Children's Hospital with clinical manifestations of airway malacia, examined by the technique of virtual bronchoscopy. Thirty five patients including 23 males and 12 females with the mean age of 3.7 +/- 1.6 months were studied. The presence of airway malacia and its location and severity were determined by virtual bronchoscopy in all studied cases; that revealed: laryngomalacia, bronchomalacia, tracheomalacia, laryngotracheomalacia and laryngobronchomalacia in 42.8, 25.7, 20, 8.6 and 2.9% of patients, respectively. Virtual bronchoscopy is a non-invasive, accurate and rapid imaging technique with an excellent validity for diagnosis of airway malacia and stenosis, therefore it can replace conventional bronchoscopy.

Validity of venous blood gas analysis for diagnosis of acid-base imbalance in children admitted to pediatric intensive care unit.

BACKGROUND: Arterial blood gas (ABG) analysis is the major tool for proper diagnosis and treatment of acid-base imbalance, but the invasive nature of arterial puncture and its possible hazards such as arterial spasm have resulted in a worldwide trend toward less-invasive diagnostic methods including venous blood gas (VBG) analysis. This study aimed to evaluate the validity of VBG and its clinical agreement with ABG in the 10 most common diseases in pediatric intensive care unit (PICU), and to answer how far it can replace the ABG test. METHODS: In a cross-sectional analytical study from September 2004 to September 2005, 200 patients in 10 disease categories received blood gas analysis. Results of blood-gas tests such as pH, PCO2 and HCO3 of both arterial and venous blood samples (simultaneously taken from each patient) were recorded and compared by statistical analysis (kappa statistics) to determine their validity and clinical agreement. RESULTS: In some diseases such as respiratory distress syndrome, neonatal sepsis, renal failure, pneumonia, diabetic ketoacidosis and status epilepticus, VBG analysis showed a good validity (high sensitivity and specificity) accompanied by a suitable clinical agreement (over 40%), but in other diseases such as neonatal seizure, shock, congestive heart failure and congenital heart disease, there was either an inappropriately low validity or a weak clinical agreement (under 20%). CONCLUSIONS: VBG can be used instead of ABG in some diseases such as respiratory distress syndrome, neonatal sepsis, renal failure, pneumonia, diabetic ketoacidosis and status epilepticus, but in other diseases such as neonatal seizure, shock, congestive heart failure and congenital heart diseases, ABG is preferable and must not be replaced by VBG. These results may be used for the formulation of future guidelines for PICU.