Nasal IgA response in wheezy infants

It is unknown why some infants wheeze during upper respiratory tract infections. One possibility is that secretory IgA, which has a major role in mucosal defence against viral infection, might be deficient in wheezy infants. The nasal IgA response to upper respiratory tract infection in 32 wheezy infants (median age 5.8 months) was compared with nine siblings (median age 2.6 years) who had nasal symptoms only. Nasal lavage was performed during infections and on follow up when free from symptoms, using inulin as a marker of dilution to determine absolute concentrations of IgA in the nasal secretions. The two groups showed a similar increase in total IgA and total protein levels during infection, but secretory IgA concentrations were unchanged. This study shows that wheezy infants have a normal nasal IgA response to infection and that the increase in total IgA during early infection is due to plasma exudation rather than increased production of secretory IgA.     

Gestational age correction for height in preterm children to seven years of age

Correction for gestational age continues to make a difference to the height SD score (SDS) to the age of seven years in very preterm babies. The height SDS for children born at 28 weeks' gestation increased by 0.25 SDS when postconceptual age was used instead of real age. Extrapolating from these results, the effect of correction would be an increase of approximately 0.32 SDS for a seven-year-old of 24 weeks' gestation. Unsatisfactory growth may be masked by a steady or increasing real age SDS in a few children. The risks of stopping using postconceptual age at two or three years include both false confidence in genuine cases of growth retardation and misinterpretation of a decrease in height SDS as evidence of growth retardation. As the number of very preterm babies who survive increases so does the importance of these observations.     

Is Gd-DTPA required for routine cranial MR imaging?

Gadopentetate dimeglumine (gadolinium diethylenetriaminepentaacetic acid [DTPA]) was administered prospectively to 500 consecutive children and adults referred for routine cranial magnetic resonance (MR) imaging over a 4-month period. Pre- and postcontrast images were blindly and independently interpreted by two experienced neuroradiologists. Specific criteria were provided to the readers to define objectively when contrast material enhancement (or lack thereof) would be considered "radiologically helpful." Contrast-enhancing lesions were observed in 99 cases (20%). In only 15 cases (3%) did Gd-DTPA permit detection of lesions not also apparent on the precontrast studies. Contrast enhancement was considered radiologically helpful in 74 of the 99 cases. Lack of enhancement was considered helpful in 112 of the 500 cases (22%). Factors that may indicate increased usefulness of Gd-DTPA include increased patient age, definite lesion seen at computed tomography or precontrast MR imaging, prior craniotomy for tumor, and clinically documented systemic or central nervous system disease. Gd-DTPA should probably be used routinely for cranial MR imaging in most patients, except, perhaps, children and young adults with normal precontrast images.     

A systematic review and meta-analysis of complications following the posterior and lateral surgical approaches to total hip arthroplasty

IntroductionTotal hip arthroplasty is one of the most commonly performed orthopaedic procedures. Despite this, medical evidence to inform the choice of surgical approach is lacking. Currently in the UK, the two most frequently performed approaches to the hip are the posterior and the direct lateral.MethodsThis systematic review was performed according to Cochrane guidelines following an extensive search for prospective controlled trials published in any language before January 2014. Of the 728 records identified from searches, 6 prospective studies (including 3 randomised controlled trials) involving 517 participants provided data towards this review.FindingsCompared with the lateral approach, the posterior approach conferred a significant reduction in the risk of Trendelenburg gait (odds ratio [OR]: 0.31, p=0.0002) and stem malposition (OR: 0.24, p=0.02), and a non-significant reduction in dislocation (OR: 0.37, p=0.16) and heterotopic ossification (OR: 0.41, p=0.13). Neither approach conferred a functional advantage. We draw attention to the paucity of evidence and the need for a further randomised trial.     

Inconsistent reporting of minimally invasive surgery errors

Introduction

Minimally invasive surgery (MIS) is a complex task requiring dexterity and high level cognitive function. Unlike surgical ‘never events’, potentially important (and frequent) manual or cognitive slips (‘technical errors’) are underresearched. Little is known about the occurrence of routine errors in MIS, their relationship to patient outcome, and whether they are reported accurately and/or consistently.

Methods

An electronic survey was sent to all members of the Association of Surgeons of Great Britain and Ireland, gathering demographic information, experience and reporting of MIS errors, and a rating of factors affecting error prevalence.

Results

Of 249 responses, 203 completed more than 80% of the questions regarding the surgery they had performed in the preceding 12 months. Of these, 47% reported a significant error in their own performance and 75% were aware of a colleague experiencing error. Technical skill, knowledge, situational awareness and decision making were all identified as particularly important for avoiding errors in MIS. Reporting of errors was variable: 15% did not necessarily report an intraoperative error to a patient while 50% did not consistently report at an institutional level. Critically, 12% of surgeons were unaware of the procedure for reporting a technical error and 59% felt guidance is needed. Overall, 40% believed a confidential reporting system would increase their likelihood of reporting an error.

Conclusion

These data indicate inconsistent reporting of operative errors, and highlight the need to better understand how and why technical errors occur in MIS. A confidential ‘no blame’ reporting system might help improve patient outcomes and avoid a closed culture that can undermine public confidence.     

Differential interleukin-1 elaboration by density-defined human monocyte subpopulations

Interleukin-1 (IL-1) is an important immunoregulatory peptide produced by monocytes and macrophages. Because mononuclear phagocytes are morphologically and functionally heterogeneous, we examined whether they differ in their ability to elaborate IL-1. We used discontinuous Percoll gradients to obtain five density-defined human blood monocyte subpopulations. Unfractionated monocytes and their subsets were compared for their ability to stimulate thymocyte proliferation. Supernatants obtained from the denser monocytes consistently contained more IL-1 activity than did supernatants from the less dense cells. This difference in IL-1 activity was the result of differences in IL-1 elaboration, not the selective production of an inhibitor of IL-1- induced thymocyte proliferation. These data demonstrate that density- defined human monocyte subpopulations differ in their capacity to elaborate IL-1.