Ian J. Ramage

Accuracy of clean-catch urine collection in infancy

OBJECTIVE To compare the accuracy of cultures of urine obtained by clean-catch urine (CCU) collection and suprapubic aspiration (SPA) in infants. DESIGN Prospective case series undertaken in a pediatric teaching hospital and associated neonatal unit. Fifty-eight paired urine cultures (CCU collection and SPA) were obtained from 49 infants with suspected urinary tract infection. The primary outcome measure was the presence or absence of significant bacteriuria on both CCU collection and SPA; secondary outcome measures were the success of SPA with ultrasound guidance compared with aspiration without ultrasound guidance. Statistical analysis was done by using a chi(2) test. RESULTS A false-positive rate of 5% and a false-negative rate of 12% were recorded. Sensitivity was 88.9% (95% CI 65.3-98.6), and specificity was 95.0% (95 CI% 83.1-99. 4). Ultrasound-assisted SPA was successful in 26 of 28 patients (93%) and in 13 of 21 patients (62%) when SPA was performed without ultrasound (chi(2) = 7.08, P =.008). CONCLUSIONS We conclude that there is a good association in results of culture of urine obtained by CCU collection and SPA and would encourage the use of the CCU technique.

Sorbitol-fermenting Escherichia coli O157, Scotland.

To the Editor: Verotoxin-producing Escherichia coli (VTEC) of serogroup O157 causes severe gastrointestinal and renal illness; clinical signs may be mild diarrhea, hemorrhagic colitis, or hemolytic uremic syndrome (HUS). Typically, 10%–15% of reported VTEC infections quickly progress to HUS (1). Sorbitol-fermenting (SF)–O157 strains have emerged in continental Europe (2,3). Some evidence suggests that SF-O157 is more frequently associated with HUS than are non-sorbitol–fermenting strains (3–6). SF-O157 shows increased adherence to colonic epithelial cells and may in turn cause a more potent inflammatory host response, resulting in a higher risk for HUS (4). The potentially greater virulence of SF-O157 requires urgent identification of its reservoir(s) and vehicle(s) of infection, as well as determination of genetic or other predisposing factors for infection with this strain. To understand whether the host pathophysiologic responses to SF-O157 and non–SF-O157 strains differ, we analyzed a cohort of children with HUS who were infected with E. coli O157. During April and May 2006, Health Protection Scotland (HPS) identified 18 cases of verotoxin-producing SF-O157 infection in Scotland, 13 of which were associated with a nursery. HUS developed in 8 of the 18 patients; those with thrombotic microangiopathy were admitted to the renal unit of a specialist pediatric hospital, which immediately reports cases of HUS to HPS as part of national surveillance (7). To test the hypothesis that SF-O157 was more virulent than non–SF-O157, we performed an age-matched, nested case–case study of HUS case-patients and analyzed host clinical markers, treatment, and outcomes from SF-O157 and non–SF-O157 cases in 2006. Clinical questionnaires, patient information sheets, and consent forms were completed by clinicians for each case-patient and returned to HPS; data were entered into a database in Epi Info version 6 (Centers for Disease Control and Prevention, Atlanta, GA, USA). Statistical analysis by t test showed that nadirs for serum albumin were significantly higher for children with SF-O157 HUS (p = 0.03; Table) than for children with non–SF-O157 HUS and that children with SF-O157 HUS had significantly more sessions of hemodialysis than did children with non–SF-O157 HUS (p = 0.01; Table). All case-patients were oligoanuric; the 2 groups did not differ with respect to this parameter. Initial signs and symptoms were similar for both sets of patients, i.e., classic VTEC symptoms of bloody diarrhea and abdominal pain. This finding is in acccordance with those of other studies of SF-O157 outbreaks, which also noted signs and symptoms compatible with VTEC-associated gastroenteritis (5,6). Table Characteristics of patients infected with non–SF-O157 versus SF-O157 Escherichia coli, Scotland, 2006* Our study highlights a number of lessons. Medical practitioners rarely have the opportunity to recognize patients at such an appreciable and predictable risk of progressing rapidly to anuric renal failure as they do when they see children with early O157 infection. Failure to appreciate the potential gravity of O157 infection and the possible development of HUS may result in avoidable illness and even death. Our investigation of the prehospital management of SF-O157 and non–SF-O157 in this cohort found no difference in pharmacologic intervention or duration of delay in admission to hospital. Our study has limitations. A number of patients in the cohort were prescribed antimicrobial drugs and/or antimotility drugs or were sent home from the local hospital without hospital admission or further monitoring; such actions potentially exacerbate clinical outcomes (1,8). We recognize that comparison of the SF-O157 outbreak strain with non–SF-O157 strains (some of which caused sporadic cases) may be a potential confounding factor in the analysis. However, recently published work has indicated no statistically significant differences in the verotoxin proteins encoded by SF-O157 or non–SF-O157 strains or in their level of toxicity (9). Other virulence factors may contribute to increased likelihood of HUS (4). Our data suggest that infection with SF-O157 results in less severe colitis than does the more common non–SF-O157 infection. Less severe colitis could result in a lower risk for renal disease because less verotoxin would be translocated into the bloodstream and bound to the kidneys. However, patients infected with SF-O157 had anuria for longer periods and consequently had longer sessions of peritoneal and hemodialysis. Although unknown bacterial or host inflammatory cytokines may contribute to enhanced disease progression, this observation is surprising and requires further investigation. Additional research is needed to learn more about the virulence of SF-O157 strains and establish other host factors that contribute to disease progression.

Renal transplant biopsy specimen adequacy in a paediatric population

Updated guidelines on the diagnosis of acute allograft rejection including criteria for biopsy specimen adequacy were published in 1999. We sought to determine the adequacy of specimens in paediatric transplant patients and identify factors influencing adequacy. All renal transplant biopsies performed between 1998 and 2003 were classified as adequate (n =25), minimal (n =19) or inadequate (n =27) in accordance with the Banff 97 criteria, and the histological diagnoses were documented. The effect on specimen adequacy of grade of operator, method of sedation, age of child, needle gauge, number of cores and total core length was then investigated. Overall, a minimal or adequate specimen was obtained in 62% of cases. No histological diagnosis could be made in 30% of all specimens, just over half of which were inadequate. Higher rates of rejection were found in adequate (52%) than inadequate (33%) samples. The grade of operator (p =0.498), the age of the child at the time of biopsy (p =0.815) and type of sedation (p =0.188) did not affect adequacy. More than one core was obtained in 38 (54%) cases, and this was significantly associated with specimen adequacy (p <0.0005) as was longer total core length (p =0.002). Clinical features in isolation are not sufficient for the diagnosis of acute allograft rejection. Renal biopsy remains the gold standard and relies on adequate specimen collection. Our data shows that specimen adequacy according to the Banff 97 guidelines is achievable in children and that more than one core at the time of sampling significantly improves this achievement. Adequate sampling reduces the risk of an inconclusive histological diagnosis.

Reversible chronic pulmonary fibrosis associated with MMF in a pediatric patient: a case report.

Abstract:  We describe a case of chronic mineralizing pulmonary elastosis in a seven‐yr‐old boy following DD renal transplantion for Wilms tumour. Fourteen months post‐transplantion he developed respiratory symptoms with lung biopsy demonstrating chronic mineralizing pulmonary elastosis thought to be secondary to immunosuppression with MMF. Symptomatic resolution occurred following MMF cessation.

Skeletal disproportion in children with chronic renal disease.

Objectives: To assess stature and skeletal disproportion in children with chronic renal disease. Methods: Cross-sectional study of height (HT), sitting height (SH), subischial leg length (SILL), sitting height/height ratio (SH:HT) and disproportion score (SH SDS minus SILL SDS) in 56 children (M:35) with median age 11.4 years (range 4.5,18.7) with chronic renal disease. Results: There were 19 children with chronic renal insufficiency, 6 receiving peritoneal dialysis and 31 after renal transplant. The median HTSDS for the whole group was –1.21 (–2.8, 0.35). The median SH:HT ratio in non-transplanted children and renal transplant were 0.51 (0.49, 0.53) and 0.50 (0.48, 0.53), respectively (p = 0.02). The median disproportion score of the whole group was –3.2 (–4.8, –1.8). There was a significant correlation between disproportion score and SH:HT (r = 0.5, p = 0.005). SH:HT ratio was negatively related to duration of illness (r = 0.4, p = 0.005). Conclusion: Children with chronic renal disease have significant body disproportion and this may be due to a disproportionately greater effect of disease and treatment on spinal growth.

Fifteen-minute consultation: the management of microscopic haematuria

Haematuria can be a troublesome symptom with various different methods of presentation and aetiologies. Microscopic haematuria is a common coincidental finding often found when the patient has presented for another reason. We will discuss the subject of haematuria but will focus the majority of this article on the discussion of microscopic haematuria, including a definition, the important features to cover in the history and examination, aetiologies to suspect in children and infants, and a suggested approach to assessing these patients in secondary care.

Not in my backyard: the state of Scottish academic paediatrics

Thank you to Dr Davies and colleagues for their timely reminder about super-hero related injuries1 …We were recently contacted by the parents of one of our newborn babies who had been discharged on Abidec drops as they were concerned that this contained arachis (peanut) oil. On discussion with colleagues we realised this fact is not widely known. The list of relatively commonly used topical preparations that contain arachis oil includes Cerumol …