Prevention of invasive infection

Background
Efforts to coordinate care throughout the lifespan between community settings, primary care practices, specialists’ practices, emergency departments, laboratories, and hospitals can significantly improve the health and well-being of individuals with a chronic disease such as SCD. Coordination models such as the medical home can facilitate this coordination. Individuals with SCD are at high risk for developing multi-system acute and chronic conditions associated with significant morbidity and mortality. Undetected signs and symptoms can begin in early childhood. For example, silent CNS infarcts can present with non-focal signs such as developmental delays or poor or declining school performance in children or changes in social role or work functioning in adults. Throughout their lives, people with SCD should be considered for formal neurocognitive evaluation when assessments reveal any of these concerns. In another example, loss of the kidney’s ability to concentrate urine occurs in most individuals with SCD and can result in large urine volumes. In children, this may result in enuresis or bedwetting.

Although treatment of SCD may ameliorate some of these complications, such therapies are often unsuccessful in completely preventing them. Therefore, the next best approach may be screening to identify risk factors and early signs of complications in order to implement measures to reduce morbidity and mortality in individuals with SCD. However, not all screening is useful. The expert panel determined that, for evidence that supports screening to be considered high-quality, it needed to meet the following requirements, which were based upon the WHO criteria but modified by the panel:
1. The condition targeted by screening is sufficiently prevalent and clinically significant in persons with SCD.
2. An accurate screening test that identifies the condition is available.
3. There is evidence that early intervention in populations identified by screening is beneficial (e.g., effective therapy exists for preventing or treating a condition).
4. Screening is associated with minimal harm.
5. Screening is cost-effective.
The methodology team conducted systematic reviews of the evidence to synthesize and evaluate relevant research on the utility of commonly used diagnostic tests in individuals with SCD (e.g., electrocardiograms, echocardiograms, pulmonary function tests, kidney function tests, various screening eye exams, brain imaging, and transcranial Doppler (TCD)) and presented the panel with evidence tables which included determinations of the evidence quality.

This chapter reviews the available evidence for health maintenance and screening and makes recommendations for children and adults with SCD. In addition to SCD-specific recommendations, this chapter also includes the USPSTF’s recommendations on clinical preventive services. The expert panel also identified recommendations from the Centers for Disease Control and Prevention/World Health Organization (CDC/WHO) report on contraceptive use, which were deemed to be particularly relevant for women with SCD and their partners; these recommendations are included in the latter part of this chapter. The experience panel reviewed the methods used by the CDC, WHO, and USPSTF, and concluded that the processes used by these organizations were consistent with those used by the panel’s methodology team.

Methodology
Complete information about the methodology for these guidelines can be found in the “Introduction and Methodology” chapter (pages 1-9). The following information, specific to this chapter, supplements the standard methodology that was conducted for all clinical chapters of these guidelines.

A comprehensive study of several databases was conducted, and all human studies in English published from January 1970 to December 2010 that addressed each PICOS question were identified A total of 313 studies were included. In the specific instances of antibiotic therapy and blood pressure screening, the review began from database inception through January and July 2011, respectively. In the case of screening, the review went through July 2010. Meta-analysis was only feasible in two areas: (1) efficacy of antibiotic prophylaxis in children and (2) hypertension (HTN) in SCD. The topics of reproductive counseling, contraception, clinical preventive health care services, and immunizations were not searched; recommendations were derived from guidelines published by professional organizations that were based on systematic reviews of broader population groups; these recommendations are labeled “Consensus-Adapted.” The key questions for this chapter can be found immediately before the Summary of the Evidence sections for the individual topics.

Detailed information on the evaluated studies as well as the observational and case studies/series referenced can be found in the evidence tables for this chapter (The Use of Prophylactic Antibiotic Therapy in Children With Sickle Cell Disease: A Systematic Review and Meta-Analysis, 2012; Blood Pressure and Sickle Cell Disease: A Systematic Review and Meta-Analysis, 2012; and The Use of Screening Tests in Patients With Sickle Cell Disease: A Systematic Review, 2012) available at http://www.nhlbi.nih.Nov/9uidclines/scd/indcx.htm.