ORIGINAL SCIENTIFIC REPORT
Long-Term Results Following Antibiotic Treatment of Acute
Appendicitis in Adults
Published online: 24 March 2017
Ó The Author(s) 2017. This article is an open access publication
Background Antibiotic treatment of acute appendicitis has gained interest and inquiries. Reports have demonstrated
both safety and high resolution of symptoms and inﬂammation following antibiotic treatment of appendicitis, but
information on long-term results is required. Our present aim was therefore to evaluate long-term recurrence rate of
initial antibiotics-alone treatment for suspected acute appendicitis.
Methods Patients with favourable response to antibiotics in earlier randomized (RCT, n = 97) and population-based
(PBT, n = 342) studies as well as subsequently treated non-randomized (Non-R, n = 271) patients are evaluated for
long-term risk to relapse demanding surgical appendectomy; altogether 710 patients.
Results Clinical characteristics among randomized and non-randomized patients were similar without any statistical
difference according to abdominal symptoms and degree of systemic inﬂammation (CRP, WCC) when antibiotic
treatment started. Females and males showed the same results. The median follow-up time was 2162 days
(5.92 years), and the range across highest and lowest follow-up was 3495 days (range 2–3497) for the entire group,
without signiﬁcant differences among subgroups (RCT, PBT, Non-R). The cumulative probability for relapse of
appendicitis demanding appendectomy was: 0.09, 0.12, 0.12 and 0.13 at 1-, 2-, 3- and 5-year follow-up, with a
probability of 0.86 ± 0.013 without appendectomy after 8 years. This may imply an overall beneﬁt of 60–70% by
antibiotics during expected 10-year follow-up accounting for initial treatment failures at 10–23% in our published
Conclusion Antibiotic treatment is safe and effective as a ﬁrst-line therapy in unselected adults with acute appen-
dicitis with a risk around 15% for long-term relapse following favourable initial treatment response.
Antibiotic treatment of acute appendicitis as alternative to
surgical appendectomy is a well-recognized possibility,
with favourable response rates of 0.77–0.91 according to
randomized and consecutively evaluated patients [1–6].
However, it is still a controversy to what extent antibiotic
treatment should be offered systematically as a ﬁrst-line
therapy [7, 8]. It has even been doubted whether antibiotics
offers signiﬁcant resolution of inﬂamed appendices .
& K. Lundholm
Surgical Metabolic Research Lab, Department of Surgery,
Sahlgrenska University Hospital and The Institute of Clinical
Sciences, University of Gothenburg, Vita Stra
ket 12, plan 2,
413 45 Go
Department of Surgery, Kalmar County Hospital, Kalmar,
World J Surg (2017) 41:2245–2250