Fistulized pilonidal cyst
Short Summary

16-year-old female with a recurrent polinidal cyst/ synus despite three previous excissions and drainage procedures. She has a re-recurrent cyst.

Patient's Questions

1) Why were the previous procedures unsuccessful in solving this condition?

2) Can you confirm the appropriateness of the surgical procedures? Are there any alternatives to surgery?
3) What is the prognosis?
Medical Background

-       No significant pathologies reported.
Onset of symptoms at the end of the summer, with the appearance of a small sac containing blood and pus in the coccyx region. The patient, female, 16, had a specialist pediatric and pediatric surgery visit at Hospital. The proposed indication was surgery following diagnostic tests including:
·         Ultrasound of skin and subcutaneous tissue: “Hyperechogenic accumulation in the subcutaneous adipose tissue, vaguely resembling a tennis racquet, from which some fistulous areas originate and extend towards the skin. An area originating from the more caudal part of the lesion appears to terminate in a dead end horizontally to the left. This area is approximately 1.5 cm. Conclusions: pilonidal cyst with ramified fistula”.
·         MRI of spine: “... a hyperintense area is visible in the intergluteal region corresponding to the group of fistulas in T2 weighted scans, performed with suppression of adipose tissue signal, and hypointense in weighted T1 scans, extending approximately 2 cm on a craniocaudal axis. This is contiguous to the coccyx structures in the sacrum/coccyx area. The structure was probed with a blunt needle and subsequently injected with a four per thousand solution of gadolinium. A small fistulous area can be seen, at the end of which there appears to be a small cystic formation and slight impregnation likely due to lymphatic drainage of more cranial fibrotic structures in the subcutaneous skin. The dimension of the cystic lumen is approximately 5-6 mm. There appears to be a fibrotic reaction extending a little more to the left.
Conclusions: pilonidal cyst with skin fistula. There appears to be no infiltration of the sacral and coccygeal structures”.
As the diagnosis of fistulized pilonidal cyst was confirmed by both tests, the patient was admitted to hospital. The surgical procedure under general anesthesia was performed two days later and the patient was discharged .  The lesion was treated weekly at the pediatric surgical unit. After the stitches were removed, the surface of the lesion reopened. Therefore, a second surgical procedure under epidural anesthesia was performed in the pediatric surgical unit.
There were no problems until the cyst started bleeding and secreting pus again. Following a plastic surgery visit, a third surgical procedure was scheduled. This procedure was particularly short and was performed under local anesthesia (the patient was admitted at 8.00 a.m. and was discharged that morning). However, after a few days, the situation had not changed and the infection that was present before the surgical procedure reappeared. At the subsequent follow-up visit, the surgeon who had performed the procedure confirmed the unsuccessful outcome of the third procedure. The worsening situation (bleeding and secretion of pus from the lesion) required further specialist visits at the plastic surgery unit, but with a different physician than the one who performed the last procedure. An antibiotic treatment was also prescribed to control the infection. In March the patient had another MRI that showed the cyst was still present: “… there is a small group of confluent microcysts surrounded by a slight edematous component extending transversally up to 15 mm approximately. The largest of these microareolae has an approximate maximum diameter of 4 mm. From this point there is a fistulous area that reaches the skin, having an approximate maximum diameter of 2-3 mm, which extends near the skin in the area of the small crust that can be seen during physical examination. No abnormalities in the coccyx structure and no other findings elsewhere”.
Therefore, the fourth surgical procedure in less than three years has been scheduled to be performed again at the plastic surgery unit .


Expert's Opinion

  1. The previous procedures were indicated but insufficiently excised the tissue responsible for causing the pondialized cyst.
  2. At this time, surgical excission of all affected and infected tissue is the most definitive treatment. Despite assidious care the reccurrence rate of polindial cysts is high, approxymately 30% or more.
  3. The prognosis is good- this is not associated with cancer or any other life threatening problem. It is surely aggrevating and miserable. With appropriate surgery and proper post operative care it should be completely erradicated.