Abstractobjective To explore barriers to and solutions for effective implementation of obstetric audit at Saint Francis Designated District Hospital in Ifakara, Tanzania, where audit results have been disappointing 2 years after its introduction.methods Qualitative study involving participative observation of audit sessions, followed by 23 indepth interviews with health workers and managers. Knowledge and perceptions of audit were assessed and suggestions for improvement of the audit process explored.results During the observational period, audit sessions were held irregularly and only when the head of department of obstetrics and gynaecology was available. Cases with evident substandard care factors were audited. In-depth interviews revealed inadequate knowledge of the purpose of audit, despite the fact that participants regarded obstetric audit as a potentially useful tool. Insufficient staff commitment, managerial support and human and material resources were mentioned as reasons for weak involvement of health workers and poor implementation of recommendations resulting from audit. Suggestions for improvement included enhancing feedback to all staff and managers to attend sessions and assist with the effectuation of audit recommendations.

Although glomerular filtration rate (GFR) in children can be measured using a gold-standard technique following injection of an exogenous marker, this invasive and cumbersome technique is not widely available and GFR is commonly estimated using serum levels of endogenous markers. Creatinine, urea, cystatin C, beta-trace protein, and beta-2 microglobulin are well-established endogenous markers of kidney function. These markers differ in site of production and effects of diet and medication, as well as renal-tubular handling and extra-renal elimination. For each marker, different methods are available for measurement. Importantly, the measurements of creatinine and cystatin C have recently been standardized with the introduction of international reference standards. In order to allow estimation of GFR from serum marker concentrations, different equations for estimated GFR (eGFR) have been developed in children, using simple or more complex regression strategies with gold standard GFR measurements as a dependent variable. As a rule, estimation strategies relying on more than one marker - either by calculating the average of single parameter equations or by using more complex equations incorporating several parameters - outperform eGFR estimations using only a single marker. This in-depth review will discuss the physiology, measurement and clinical use of creatinine, urea, cystatin C, beta-trace protein, and beta-2 microglobulin in children. It will also address the generation of eGFR equations in children and provide an overview of currently available eGFR equations for the pediatric age group.

Estimating glomerular filtration rate (GFR) in adults by using the average of values obtained by a cystatin C- (eGFR) and a creatinine-based (eGFR) equation shows at least the same diagnostic performance as GFR estimates obtained by equations using only one of these analytes or by complex equations using both analytes. Comparison of eGFR and eGFR plays a pivotal role in the diagnosis of Shrunken Pore Syndrome, where low eGFR compared to eGFR has been associated with higher mortality in adults. The present study was undertaken to elucidate if this concept can also be applied in children. Using iohexol and inulin clearance as gold standard in 702 children, we studied the diagnostic performance of 10 creatinine-based, 5 cystatin C-based and 3 combined cystatin C-creatinine eGFR equations and compared them to the result of the average of 9 pairs of a eGFR and a eGFR estimate. While creatinine-based GFR estimations are unsuitable in children unless calibrated in a pediatric or mixed pediatric-adult population, cystatin C-based estimations in general performed well in children. The average of a suitable creatinine-based and a cystatin C-based equation generally displayed a better diagnostic performance than estimates obtained by equations using only one of these analytes or by complex equations using both analytes. Comparing eGFR and eGFR may help identify pediatric patients with Shrunken Pore Syndrome.

Estimation of kidney function is often part of daily clinical practice, mostly done by using the endoge-nous glomerular filtration rate (GFR)-markers creatinine or cystatin C. A recommendation to use both markers in parallel in 2010 has resulted in new knowledge concerning the pathophysiology of kidney disorders by the identification of a new set of kidney disorders, selective glomerular hypofiltration syndromes. These syndromes, connected to strong increases in mortality and morbidity, # Linnea Malmgren and Carl Öberg contributed equally as first authors.