Should blood gas analysis be part of the diagnostic workup of short children? Auxological data and blood gas analysis in children with renal tubular acidosis.

BACKGROUND: Renal tubular acidosis (RTA) is a rare cause of growth failure, therefore it is uncertain whether routine screening with blood gas analysis of short infants and children is cost-effective. OBJECTIVE: To investigate the clinical, growth and laboratory parameters in children with RTA to estimate the possible value of laboratory screening for this disorder in infants and children referred for short stature according to a recent guideline. METHOD: Retrospective chart analysis of 30 children diagnosed between 1978 and 2005 in The Netherlands and 3 centers in Belgium. RESULTS: The current guideline for short stature detected 33% of children with RTA. Assuming a pre-test probability of RTA of 0.6 per 100,000 births, the likelihood ratio of poor growth was 58 and 17 below and above 3 years, respectively. Sensitivity was 17/30 and 12/24 for a -2.0 SDS cutoff for weight and body mass index, respectively. In infants and toddlers diagnosed before 3 years of age, the mean weight loss was 1.5 SD, and 0.8 SDS in older children. In short children >3 years RTA was extremely rare, always associated with clinical symptoms, and rarely detected by blood gas analysis. CONCLUSION: According to our data a decreasing weight SDS for age is a sufficient indication to perform blood gas analysis in children <3 years of age, particularly in the presence of additional clinical features, whereas it can be omitted in short children >3 years of age.

Developing evidence-based guidelines for referral for short stature.

OBJECTIVE: To establish evidence-based guidelines for growth monitoring on a population basis. STUDY DESIGN: Several auxological referral criteria were formulated and applied to longitudinal growth data from four different patient groups, as well as three samples from the general population. RESULTS: Almost 30% of pathology can be detected by height standard deviation score (HSDS) below -3 or at least two observations of HSDS below -2.5 at a low false-positive rate (<1%) in 0-3-year-old infants. For 3-10-year olds, a rule concerning distance to target height of >2 SD in combination with HSDS <-2.0 has the best predictive value. In combination with a rule on severe short stature (<-2.5 SDS) and a minor contribution from a rule on "height deflection", 85.7% of children with Turner syndrome and 76.5% of children who are short because of various disorders are detected at a false-positive rate of 1.5-2%. CONCLUSIONS: The proposed guidelines for growth monitoring show high sensitivity at an acceptably low false-positive rate in 3-10-year-old children. Distance to target height is the most important criterion. Below the age of 3 years, the sensitivity is considerably lower. The resulting algorithm appears to be suitable for industrialised countries, but requires further testing in other populations.

Growth hormone treatment in children with rheumatic disease, corticosteroid induced growth retardation, and osteopenia.

BACKGROUND: In children with severe rheumatic disease (RD), treatment with corticosteroids (CS) is frequently needed and growth retardation and osteopenia may develop. A beneficial effect of human growth hormone (hGH) has been reported but mostly in trials without a control group. AIMS: To study the effect of hGH on growth, bone mineral density (BMD), and body composition, taking the disease activity and CS use into account. METHODS: Randomised controlled trial on 17 prepubertal RD patients with growth retardation and/or decreased BMD. The hGH group (n = 10) received treatment with hGH 4 IU/m2/day (approximately 0.045 mg/kg/day) during two years. The controls (n = 7) received no GH treatment. RESULTS: During the two year study period the disease activity, and use of CS and methotrexate (MTX) did not differ between the groups. There was a significant mean increase in height standard deviation score (HSDS) in the hGH group (0.42+/-0.16 SDS) and a non-significant decrease in the controls (-0.18+/-0.11 SDS). Change in BMD did not differ significantly between the groups, although the increase in BMD for lumbar spine within the hGH group was significant. Lean body mass improved significantly in the hGH group compared to controls (0.64+/-0.19 SDS versus -0.20+/-0.17 SDS), while the decrease in percentage fat was not significant. CONCLUSIONS: There was a significant effect of hGH on growth and lean body mass, but a longer duration of treatment might be necessary to evaluate the effect of hGH on BMD.

Growth monitoring and diagnostic work-up of short stature: an international inventorization.

BACKGROUND/AIMS: Growth monitoring is almost universally performed, but few data are available on which referral criteria and diagnostic work-up are used worldwide for children with short stature. METHODS: A short questionnaire, containing questions on auxological screening and on diagnostic criteria for short stature, was sent to all members of the European Society of Paediatric Endocrinology (ESPE) and to several pediatric endocrinologists outside Europe. RESULTS: Responses were received from 36 countries. In 27 (75%) a child health care program existed and in 14 (39%) there was a protocol for referral of children with growth retardation. Height for age was mostly used as a referral criterion. Sixteen countries (45%) reported having a guideline in secondary health care for diagnostic work-up. Although all countries agreed on having biochemical, radiological and/or genetic tests in the diagnostic work-up, there was a wide variety of recommended tests. CONCLUSIONS: There is little consensus on referral criteria and diagnostic work-up of children with short stature among industrialized countries. There is a need to establish evidence-based guidelines.

Many referrals under Dutch short stature guidelines.

The number of referrals under strict adherence to the Dutch consensus guidelines for short stature was estimated using longitudinal data from 970 children (0-10 years). Results showed that over 38% of all children would have to be referred one or more times. There is therefore a clear need to revise the current guidelines.

Towards evidence based referral criteria for growth monitoring.

AIMS: To evaluate the performance of growth monitoring in detecting diseases. Turner's syndrome (TS) is taken as the target disease. METHODS: Case-control simulation study. Three archetypal screening rules are applied to longitudinal growth data comparing a group with TS versus a reference group from birth to the age of 10 years. Main outcome measures were sensitivity, specificity, and median referral age. RESULTS: Clear differences in performance of the rules were found. The best rule takes parental height into account. Combining rules could improve diagnostic accuracy. CONCLUSION: Growth monitoring is useful to screen for TS. A combined rule that takes absolute height SDS, parental height, and deflection in height velocity into account is the best way to do this. Similar research is needed for other diseases, populations, and ages, and the results should be synthesised into evidence based referral criteria.