[Evidence for the digital rectal examination in the emergency assessment of acute abdominal pain].

BACKGROUND: Physical examination of patients with undifferentiated abdominal pain (UAP) in the emergency room traditionally calls for digital rectal examination (DRE). Without a DRE, many textbooks deem a clinical examination incomplete. On the other hand, patients as well as physicians often feel uncomfortable with this breach of privacy involving a DRE. Especially emergency rooms do not offer an atmosphere where a relationship with the necessary mutual trust can be built up. In this light, the objective of this analysis is to assess the evidence for DRE via a systematic search of the relevant literature.

METHODS AND RESULTS: A systematic search in Pubmed, Medline coupled with manual research laid the basis for the evaluation of relevant publications from January 1990 to March 2010. Keywords for the search were: "digital rectal examination" in combination with "acute abdominal pain", "acute abdomen" or "appendicitis". From the raw data of relevant publications, we extracted results into contingency tables and completed missing data. Above all parameters, we determined the likelihood ratios (LR) with corresponding 95 % confidence intervals to assess test quality. Opinions in the evaluated literature and many national and international textbooks diverge significantly on the necessity of DRE. Six studies question the significance of DRE when evaluating patients with undifferentiated abdominal pain and appendicitis, respectively. Out of these studies, five are prospective and one is retrospective. Overall, the diagnostic test quality of DRE was low in all studies with LR + in the range from 0.78 to 1.61 and LR -  from 0.91 to 1.29, respectively. No diagnostic relevance for DRE in combination with acute abdominal pain was found in these studies. Furthermore, in none of the reviewed cases did DRE have a relevant impact on management.

CONCLUSION: The recommendation of generally applying DRE in the emergency room needs to be questioned critically. No evidence for the necessity and significance was found in the reviewed literature. Independently, these findings do not touch on the unequivocal indication of the DRE as a tool for assessing other specific conditions as well as screening for prostate or rectal cancer.