PILONIDAL CYSTS AND SINUSES

Global Gender Differences in Pilonidal Sinus Disease: A Random-Effects Meta-Analysis

BACKGROUND

Pilonidal sinus disease (PSD) is traditionally associated with young male patients. While PSD is rare in Asia and Africa, lifestyles are changing considerably throughout the so-called developed world. We question that PSD is an overwhelmingly male disease and that the proportion of women suffering from PSD is worldwide evenly distributed in a homogenous matter.

METHODS

We analysed the world literature published between 1833 and 2018, expanding on the database created by Stauffer et al. Following correction for gender bias with elimination of men-only and women-only studies, data were processed using random-effects meta-analysis in the technique of DerSimonian and Laird.

RESULTS

The share of female pilonidal sinus disease patients analysed from all studies available in the world literature is 21%. There are marked regional differences including South America (39%), North America as well as Australia/New Zealand (29%) and Asia (7%), which are highly significant. These results stand fast even if analysis without gender bias corrections was applied.

CONCLUSION

The share of female patients suffering from PSD is considerable. It is time to think of PSD as a disease of both men and women. Previously unknown, there are significant regional differences worldwide; the reason(s) for the regional differences is still unclear.

Impact of geography and surgical approach on recurrence in global pilonidal sinus disease

Pilonidal sinus disease (PSD) is increasing globally. A recent meta-analysis and merged-data analysis showed that recurrence rates in PSD depend essentially on follow-up time and specific surgical procedures. However, the global distribution of surgical approaches and respective recurrence rates have never been studied in PSD. We aimed at studying the impact of geographic distribution of surgical approaches to treat PSD and subsequent geography-specific recurrence rates. We searched relevant databases as described previously. Recurrence rates were then associated with reported follow-up times and geographic origin. We simulated individual patients to enable analogy across data. Globally, recurrence rates range from 0.3% for Limberg/Dufourmentel approaches (95% CI 0.2–0.4) and flaps (95% CI 0.1–0.5) and up to 6.3% for incision (95% CI 3.2–9.3) at 12 months. Recurrence rates range from 0.3% for Karydakis/Bascom approaches (95% CI 0.0–0.8) up to 67.2% for incision (95% CI 7.5–100) in the USA, and 0.0% for primary asymmetric closure in Germany (95% CI 0.0–0.0). Our analysis shows that recurrence rates in PSD not only depend on therapeutic approaches and follow-up time but also on geography. Primary asymmetric closure and various flap techniques remain superior regardless of the geographical region. Some approaches have extraordinarily good outcomes in specific countries.

Common surgical procedures in pilonidal sinus disease: A meta-analysis, merged data analysis, and comprehensive study on recurrence

We systematically searched available databases. We reviewed 6,143 studies published from 1833 to 2017. Reports in English, French, German, Italian, and Spanish were considered, as were publications in other languages if definitive treatment and recurrence at specific follow-up times were described in an English abstract. We assessed data in the manner of a meta-analysis of RCTs; further we assessed non-RCTs in the manner of a merged data analysis. In the RCT analysis including 11,730 patients, Limberg & Dufourmentel operations were associated with low recurrence of 0.6% (95%CI 0.3-0.9%) 12 months and 1.8% (95%CI 1.1-2.4%) respectively 24 months postoperatively. Analysing 89,583 patients from RCTs and non-RCTs, the Karydakis & Bascom approaches were associated with recurrence of only 0.2% (95%CI 0.1-0.3%) 12 months and 0.6% (95%CI 0.5-0.8%) 24 months postoperatively. Primary midline closure exhibited long-term recurrence up to 67.9% (95%CI 53.3-82.4%) 240 months post-surgery. For most procedures, only a few RCTs without long term follow up data exist, but substitute data from numerous non-RCTs are available. Recurrence in PSD is highly dependent on surgical procedure and by follow-up time; both must be considered when drawing conclusions regarding the efficacy of a procedure.