Causes

1. Currently, the exact aetiology of the pilonidal sinus is unclear. According to the experts:
2. The skin gets stretched in the tailbone region when you sit or bend. This stretching causes hair strands in that area to break.
3. The hair thus becomes loose and, along with dead skin, get pushed under the skin when you perform any movement. 
4. Our body treats the loosened hair and dead skin cells as a foreign substance. This process triggers an immune response, resulting in a cyst that is filled with fluid

Signs & Symptoms

1. A non-infected pilonidal sinus or cyst does not cause any symptoms. However, if you have an infected pilonidal cyst, the following symptoms and signs may be noted:
2. Pain and discomfort in the affected area (usually near the buttocks), especially after sitting for long periods 
3. Tenderness, swelling, warmth and redness in the area surrounding the tailbone or near the cyst
4. Pus drainage through a small dimple or opening (sinus tract) in the skin over or near the pilonidal cyst located between the buttocks
5. Low-grade fever
6. Nausea
7. Fatigue (tiredness)
8. Presence of one or more small openings (pits) between your buttocks through which the sinus tract opens into the skin.

Diagnosis

1. The diagnosis is made by:
2. Based on your symptoms, you will have to undergo a complete physical examination, where your primary care doctor will carefully examine the area between your buttocks for signs of a pilonidal cyst.
3. Your primary care doctor will generally diagnose a pilonidal cyst/sinus based on its location and appearance.
4. Some rare cases will require you to undergo CT (Computed Tomography) or MRI (Magnetic Resonance Imaging) scans to check for further complications such as a sinus cavity

Treatment

1. If you have a pilonidal cyst without any troublesome symptoms, then it may get well on its own. If you have had the cyst for an extended period, the symptoms may come and go. However, if your cyst is associated with troublesome symptoms, then your primary care doctor can suggest one of the following methods for its treatment (or prevention):
2. Draining a pilonidal cyst: In this procedure, the surgeon makes a small cut on the infected cyst to drain it.
3. Antibiotics: Antibiotics may be prescribed for the skin inflammation or infection associated with the pilonidal cyst. However, only antibiotics may not be enough to treat the infected cyst.
4. Hair removal: Laser therapy for removing thick hair and ingrowths can help prevent recurrence of pilonidal cyst.
5. At home, you can apply warm compresses to the affected area for immediate relief and use a buttock cushion to soothe the pain.[1,6]
6. Surgery: Depending on the intensity of your symptoms and your condition, you may need to undergo surgery for the complete removal of the cyst. However, the cyst may recur even after surgery if you have a family history of pilonidal cysts or if your condition has worsened.

Minor surgery to drain pus from the sinus:

1. If your sinus is uncomplicated, you will need minor surgery to remove the pus from the abscess.
2. You will be given general/local anaesthesia, depending upon the size of the sinus.
3. You will be asleep during the surgery if the surgeon opts for general anaesthesia, while you will remain conscious in the case of local anaesthesia.
4. The surgeon will drain the cyst/abscess by making a small hole in the cyst.

Surgery to remove sinus (wound left open):

1. This surgery is done for a repeatedly infected or large sinus.
2. General anaesthesia is used for this procedure.
3. The sinus is cut, and some surrounding skin is also removed.
4. For natural healing, the wound is left open.
5. After this procedure, there is the lowest risk of sinus recurrence.
6.  
7. Surgery to remove sinus (wound closed):
8. This surgery is used to treat a repeatedly infected or large sinus.
9. General anaesthesia is used for this procedure.
10. The sinus is extracted, and an oval-shaped flap of skin is also cut on either side of it. Finally, the two sides are stitched together.
11. The recovery time is shorter for this surgery than the other type (wound left open). However, there is a higher risk of infection after this type of surgery.[7]

How to Prepare for the Doctor Consultation?

What can you do?

1. Here are a few tips to be well prepared for your consultation with the doctor:
2. Make a list of your previous and ongoing treatments so that your doctor can understand the cause of your symptoms.
3. Bringing a friend or relative to the doctor's office to remind you if you forget something you planned to discuss is always helpful.
4. Let your doctor know the recent updates in your life since your last visit. This also includes if you have recently started taking any medications.[8]

What to expect from the doctor?

Your primary care doctor will ask about your symptoms and make a diagnosis depending on the location and appearance of the cyst and by using other diagnostic methods.[1-3]

What questions should you ask the doctor?

Once you consult your primary care doctor regarding your pilonidal cyst, you can clear doubts or concerns, if any, such as: 

Is there a permanent cure for pilonidal cyst disease?

How can the recurrence of pilonidal disease be prevented?

Does the pilonidal cyst go away on its own?

Is pilonidal cyst a life-threatening disease?

Should I leave work if I have a pilonidal cyst?

1)Endoscopic pilonidal sinus treatment is effective, with a short and painless postoperative period, and easy wound care.

Risks if not Treated in Time 

1. If you do not get an infected pilonidal cyst/sinus treated, you may experience the following complications:
2. Acute pilonidal cyst: If you ignore the symptoms of the disease, you may develop an acute pilonidal cyst. However, it will be a one-time infection.
3. Chronic pilonidal cyst: 
4. If you do not treat the cyst in its early stages, it will worsen and form a sinus cavity (space) under your skin. 
5. At this stage, it is essential to remove it by surgery.
6. A chronic cyst can lead to the formation of abscesses (swollen pockets of infection).
7. A systemic infection: It is an infection that affects your entire body. It can turn life-threatening.
8. Cancer: A pilonidal cyst can lead to squamous cell carcinoma (cancer), although this condition is rare.