This report examined the available evidence from randomized trials and nonrandomized studies on the diagnosis and management of acute sinusitis in children. The major conclusion is that, considering the frequency of this very common condition, the amount of high-quality evidence is remarkably limited. It is important to note that most randomized data on adolescents may have been inextricably merged with data on adults in previous studies, and it is unclear whether adolescents should differ from adults in the diagnosis and management of acute sinusitis. However, for the purely pediatric population, evidence is sparse.

There is very little evidence on how to accurately diagnose acute sinusitis in childhood. Plain film radiography shows only modest concordance with clinical diagnosis, and the concordance depends largely on how a clinical diagnosis is defined. Other imaging modalities and irrigation have no clear role in the diagnostic management of the syndrome. There is no consensus on which clinical signs and symptoms are most useful for diagnosing this condition, and very limited attention has been given to this issue. Although one small trial has shown the superiority of antibiotics over placebo, its applicability to settings where sinusitis is defined by different criteria is uncertain. The available evidence also suggests that the various antibiotics used for pediatric sinusitis do not differ in their efficacy rates. Nevertheless, given the sparse evidence, modest differences could have been missed. In the absence of a gold standard for diagnosis, trials involving several hundred children would be needed to show such differences. There is no convincing evidence to support the use of ancillary treatment with decongestant-antihistamines and very limited evidence on the use of steroids.

On the basis of the current evidence, it is difficult to specify the prime clinical criteria for diagnosing acute sinusitis in children and which diagnostic tests are warranted. Many traditional clinical criteria seem to have no discriminating ability between sinusitis and rhinitis. It is possible that these entities are very difficult, if not impossible, to separate and that they may co-exist to some extent in most cases. The term "acute rhinosinusitis" thus may be more appropriate and may need to replace the term "acute sinusitis." Radiographs appear to be abnormal in approximately 80 percent of cases where strict clinical criteria have been applied (Barlan, Erkan, Bakir, et al., 1997; Jannert, Andreasson, Helin, et al., 1982; Wald, Chiponis, and Ledesma-Medina, 1986), but the rates of abnormal plain film radiographsy are substantially lower when clinical criteria are less strict. However, there is insufficient evidence regarding any of the imaging modalities, CT is considered expensive for routine use, and sinus aspiration is invasive and cumbersome. Concordance of the different diagnostic modalities seems to be very low, but additional data are warranted. In the absence of a true "gold standard," even diagnostic concordance would not be equivalent to diagnostic accuracy, and the role of any diagnostic tests, including plain film radiography, in the management of acute uncomplicated rhinosinusitis is uncertain. A decision analysis in our original evidence report (Lau, Zucker, Engels, et al., 1999) suggests that imaging studies may not be cost effective at any level of suspected acute bacterial rhinosinusitis. It is possible the condition may be overdiagnosed and overtreated currently in some community settings (Aitken and Taylor, 1998). On the other hand, in the absence of clear "gold standard" diagnostic criteria, it also conceivably could be underdiagnosed and undertreated in other settings.

The therapeutic management of acute uncomplicated sinusitis is even more controversial. Given the very high rates of spontaneous resolution, there is no evidence to support the use of antibiotic therapy in children with a low likelihood of acute bacterial sinusitis. Antibiotics showed superiority to placebo in a population defined by nasal discharge or cough that were not improving for at least 10 days and had positive radiographs. Perhaps obtaining a radiograph is not necessary if these clinical criteria exist for more than 10 days, since almost 80 percent of these children would have a positive radiograph. Empirical treatment with antibiotics may be warranted in such cases. However, it is unlikely that the use of antibiotics can be supported by the data in other groups of children, such as those without nasal discharge or cough, those with shorter duration of symptoms, and those with improving symptoms. Spontaneous recovery rates in these groups are likely to be too high for antibiotics to offer any meaningful benefit.

In addition, if antibiotic treatment is prescribed, limited evidence supports the use of amoxicillin initially, unless there is a history of allergy to beta-lactams. There is no evidence currently that newer broad-spectrum antibiotics offer any advantage over amoxicillin, and convincing data from studies of adults show the equivalence of amoxicillin to such antibiotics for the treatment of acute sinusitis. Nevertheless, the applicability of the adult findings to children and the clinical relevance, if any, of increasing resistance rates among common pathogens need to be documented in properly designed studies.

Finally, the current evidence does not offer any clear indication for the use of ancillary measures. Although antihistamines and decongestants are routinely used, there is no strong randomized evidence to justify their use in children. Randomized evidence for the use of steroids comes from a single small trial (Barlan, Erkan, Bakir, et al., 1997). Clearly, more evidence is needed to clarify the appropriate use of these agents.

The strongest message conveyed in this report is the paucity of the evidence. In addition, we identify several important questions that need to be addressed in future studies. We were surprised to find that despite the presence of an extensive bibliography on sinusitis in children, actual evidence on the diagnosis and management of acute uncomplicated sinusitis in children is very limited. We encountered over 450 reports on complications of sinusitis, mostly case reports or case series. While it is important to know about the rare complications of this disease, it is questionable whether all these case reports and small case series give us really useful information, when in comparison only a few studies deal with common, uncomplicated forms of the infection. We also were surprised at the number of reviews we encountered in our search: a total of 233 nonsystematic review articles, compared with 21 primary studies with analyzable original data. The paucity of primary data may be dueresult from to the difficulties encountered when studying a pediatric population of applying the necessary rigorous methodologies that are needed to generate high-quality information. Obviously, more evidence-based research on this common infection is needed.