Familial tailgut cysts in two sisters presenting with sacral dimple sign: a case report.
6 affiliations
- 1Department of Colorectal Surgery, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, 250014, Shandong, China.
- 2Department of Colorectal Surgery, The First Affiliated Hospital of Shandong First Medical University, Jinan, 250013, Shandong, China. [email protected].
- 3Department of Pharmacology, Faculty of Veterinary Medicine, Cairo University, Giza, 12211, Egypt.
- 4Department of Medical Pharmacology, Medical Faculty, Ataturk University, Erzurum, Turkey.
- 5Department of Pathology, Affiliated Hospital of Shandong University of Traditional Chinese Medicine, Jinan, China.
- 6First School of Clinical Medicine, Shandong University of Traditional Chinese Medicine, Jinan, 250014, Shandong, China.
Abstract
Background
Tailgut cysts are rare congenital cystic lesions arising from remnants of the embryological postanal primitive gut. Familial clustering of tailgut cysts has been rarely reported, and the association with sacral dimple sign as an early diagnostic indicator remains underexplored. We report two cases of familial tailgut cysts in sisters who presented with sacral dimple sign.Case presentation
Two female siblings of Asian ethnicity presented with sacrococcygeal lesions. Patient 1, a 17-year-old girl, experienced a 7-day history of localized tenderness and swelling over the sacrococcygeal region, with a palpable mass and a feeling of local fullness in the perianal area, accompanied by low-grade fever (up to 38 °C). Physical examination revealed a posterior anal dimple ("sacral dimple sign") with marked tenderness over the presacral soft tissues, without bony tenderness. Digital rectal examination revealed a smooth, non-tender cystic mass palpable posteriorly, with intact rectal mucosa and no evidence of fistulous tract or induration. Magnetic resonance imaging (MRI) and endorectal ultrasound (EAUS) demonstrated a presacral cystic lesion with features suggestive of superimposed infection. Patient 2, an 8-year-old girl (the younger sister), was noted at birth to have a postanal dimple but remained asymptomatic. MRI and EAUS demonstrated disorganized soft-tissue signals posterior to the anal canal. Both patients underwent complete surgical excision of the cysts. Postoperative histopathology in both cases confirmed the diagnosis of tailgut cyst. Both patients recovered well postoperatively, and at 12‑month follow‑up, no recurrence or complications were observed.Conclusions
Familial tailgut cysts, although extremely rare, may have developmental or genetic underpinnings. The "sacral dimple sign" should raise clinical suspicion for an underlying tailgut cyst. Early imaging evaluation and complete surgical excision can achieve excellent outcomes.
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BibTeX
@article{liu2026familial,
title = {{Familial tailgut cysts in two sisters presenting with sacral dimple sign: a case report.}},
author = {Congcong Liu and Yuantao Li and Benjun Wang and A M Abd El-Aty and Minmin Yu and Fan An},
journal = {Journal of medical case reports},
year = {2026},
month = aug,
doi = {10.1186/s13256-026-06443-8},
url = {https://europepmc.org/article/MED/42958327},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - Familial tailgut cysts in two sisters presenting with sacral dimple sign: a case report.
AU - Congcong Liu
AU - Yuantao Li
AU - Benjun Wang
AU - A M Abd El-Aty
AU - Minmin Yu
AU - Fan An
PY - 2026
DA - 2026/08/03
JO - Journal of medical case reports
DO - 10.1186/s13256-026-06443-8
UR - https://europepmc.org/article/MED/42958327
AB - Background Tailgut cysts are rare congenital cystic lesions arising from remnants of the embryological postanal primitive gut. Familial clustering of tailgut cysts has been rarely reported, and the association with sacral dimple sign as an early diagnostic indicator remains underexplored. We report two cases of familial tailgut cysts in sisters who presented with sacral dimple sign.Case presentation Two female siblings of Asian ethnicity presented with sacrococcygeal lesions. Patient 1, a 17-year-old girl, experienced a 7-day history of localized tenderness and swelling over the sacrococcygeal region, with a palpable mass and a feeling of local fullness in the perianal area, accompanied by low-grade fever (up to 38 °C). Physical examination revealed a posterior anal dimple ("sacral dimple sign") with marked tenderness over the presacral soft tissues, without bony tenderness. Digital rectal examination revealed a smooth, non-tender cystic mass palpable posteriorly, with intact rectal mucosa and no evidence of fistulous tract or induration. Magnetic resonance imaging (MRI) and endorectal ultrasound (EAUS) demonstrated a presacral cystic lesion with features suggestive of superimposed infection. Patient 2, an 8-year-old girl (the younger sister), was noted at birth to have a postanal dimple but remained asymptomatic. MRI and EAUS demonstrated disorganized soft-tissue signals posterior to the anal canal. Both patients underwent complete surgical excision of the cysts. Postoperative histopathology in both cases confirmed the diagnosis of tailgut cyst. Both patients recovered well postoperatively, and at 12‑month follow‑up, no recurrence or complications were observed.Conclusions Familial tailgut cysts, although extremely rare, may have developmental or genetic underpinnings. The "sacral dimple sign" should raise clinical suspicion for an underlying tailgut cyst. Early imaging evaluation and complete surgical excision can achieve excellent outcomes.
SN - 1752-1947
ER -