What are pilonidal cysts? What causes them? When should you see a doctor? How are they diagnosed and treated? Get all the answers in this comprehensive guide.

Understanding Pilonidal Cysts

A pilonidal cyst is a type of cyst that develops at the bottom of the tailbone, or coccyx. It can become infected and filled with pus, leading to a painful condition known as a “pilonidal abscess.” Pilonidal cysts are more common in men than women and are often seen in younger individuals.

Causes of Pilonidal Cysts

The exact cause of pilonidal cysts is not fully understood, but there are several theories. Most doctors believe that ingrown hairs are a common cause, as hair follicles are often found within the cyst. Another theory is that pilonidal cysts can develop after a trauma to the tailbone region.

During World War II, more than 80,000 soldiers developed pilonidal cysts, which were sometimes referred to as “Jeep disease” due to the belief that the irritation from riding in bumpy Jeeps contributed to their development.

Other risk factors for pilonidal cysts include obesity, excessive hair growth, lack of exercise, prolonged sitting, and excessive sweating.

Symptoms of Pilonidal Cysts

The main symptoms of a pilonidal cyst include:

• Pain, redness, and swelling at the bottom of the spine
• Drainage of pus or blood from the cyst
• Foul odor from the pus
• Tenderness to the touch
• Fever

The size of the cyst can vary greatly, ranging from a small dimple to a large, painful area.

Diagnosing Pilonidal Cysts

To diagnose a pilonidal cyst, your doctor will perform a physical examination and ask you questions about your symptoms, such as when they first started and if you’ve had similar issues in the past. They may also inquire about any medications or supplements you’re taking.

During the early stages of infection, the symptoms may not be severe, so it’s important to call your doctor if you notice any of the signs of a pilonidal cyst.

Treating Pilonidal Cysts

Antibiotics alone cannot heal a pilonidal cyst, but doctors have several treatment options available:

• Incision and Drainage: This is the preferred method for a first pilonidal cyst. The doctor makes a cut into the cyst, drains it, and removes any hair follicles, leaving the wound open and packing it with gauze.
• Marsupialization: In this procedure, the doctor drains the cyst, removes any pus and hair, and then sews the edges of the cut to create a pouch. This allows for a smaller, shallower incision and doesn’t require daily packing of the wound.
• Incision, Drainage, and Wound Closure: In this technique, the cyst is drained, and the wound is fully closed after surgery. This method is less likely to require further treatment, but it also has a higher risk of recurrence.
• Other Surgical Procedures: These include complete cyst and cyst wall excision, the use of fibrin glue, and punch biopsies to remove only the diseased tissue.

Regardless of the treatment method, it’s important to follow your doctor’s instructions for at-home care, such as keeping the area clean and monitoring for signs of infection.

After Surgery

Even after successful treatment, pilonidal cysts may recur. To help prevent this, it’s important to keep the area clean, avoid excessive sweating, and maintain good hygiene habits. Regular follow-up appointments with your doctor will also allow them to monitor the healing process and catch any new issues early.

Key Takeaways

Pilonidal cysts are a type of cyst that can develop at the bottom of the tailbone, leading to a painful, infected condition known as a pilonidal abscess. While the exact cause is not fully understood, ingrown hairs and trauma to the area are believed to be contributing factors.

Symptoms of a pilonidal cyst include pain, redness, swelling, drainage of pus or blood, and a foul odor. Doctors can diagnose the condition through a physical examination and by asking about your symptoms.

Treatment options include incision and drainage, marsupialization, and various surgical procedures. It’s important to follow your doctor’s instructions for at-home care and attend regular follow-up appointments to monitor for any recurrence of the condition.

Symptoms, Causes, Diagnosis, Treatment, Surgery

Written by WebMD Editorial Contributors

• What Causes a Pilonidal Cyst?
• Symptoms
• When Should I Call a Doctor?
• Diagnosis
• What Can I Do to Feel Better?
• Treatments
• After Surgery
• More

There’s a type of cyst you can get at the bottom of your tailbone, or coccyx. It’s called a pilonidal cyst, and it can become infected and filled with pus. Once infected, the technical term is “pilonidal abscess,” and it can be painful.

It looks like a large pimple at the bottom of your tailbone. It is more common in men than in women. It usually happens more often in younger people.

People who sit a lot, such as truck drivers, have a higher chance of getting one.

They can be treated. If your cyst becomes a problem, your doctor can drain it or take it out through surgery.

Most doctors think that ingrown hairs are the reason for many of them. Pilonidal means “nest of hair,” and doctors sometimes find hair follicles inside the cyst.

Another theory is that pilonidal cysts appear after a trauma to that region of your body.

During World War II, more than 80,000 soldiers got pilonidal cysts that put them in the hospital. People thought they were because of irritation from riding in bumpy Jeeps. For a while, the condition was called “Jeep disease.”

You might be more likely to get one if you were born with a small dimple in the skin between your buttocks. This dimple can tend to get infected, though doctors aren’t exactly sure why.

Other risk factors include obesity, large amounts of hair, not enough exercise, prolonged sitting, and excessive sweating.

The symptoms of a pilonidal cyst include:

• Pain, redness, and swelling at the bottom of the spine
• Pus or blood draining out of it
• Bad smell from the pus
• Tenderness to the touch
• Fever

They can vary in size. Yours may be a small dimple or cover a large, painful area.

A pilonidal cyst is an abscess or boil. Treatment may include antibiotics, hot compresses and topical treatment with depilatory creams. In more severe cases it needs to be drained, or lanced, to heal. Like other boils, it does not get better with antibiotics.

If you have any of the symptoms, call your doctor.

Your doctor can diagnose a pilonidal cyst with a physical exam and by asking you questions about it. Among the things they may ask you:

• When did you first feel symptoms?
• Have you had this problem before?
• Have you had a fever?
• What medications or supplements do you take?

Early in the infection of a pilonidal cyst, the redness, swelling, and pain may not be too bad. Some things you might want to try:

• To ease any pain, soak in a tub of warm water. Sometimes, your cyst may open and drain on its own this way.
• Take nonprescription pain medicine, but follow the dosing instructions.
• Keep the cyst and area around it clean and dry.

Antibiotics do not heal a pilonidal cyst. But doctors have any number of procedures they can try. Here are some options:

Incision and drainage: This is the preferred method for a first pilonidal cyst. Your doctor makes a cut into the cyst and drains it. They remove any hair follicles and leaves the wound open, packing the space with gauze.

Advantage — It’s a simple procedure done under local anesthesia, meaning just the area around the cyst is numbed.

Disadvantage — You have to change the gauze often until the cyst heals, which sometimes takes up to 3 weeks.

Marsupialization: In this procedure, your doctor makes a cut and drains the cyst, removing pus and any hair that are inside. They’ll sew the edges of the cut to the wound edges to make a pouch.

Advantages — This is outpatient surgery under local anesthesia. It also lets the doctor make a smaller, shallower cut so that you don’t need to take out and repack gauze daily.

Disadvantages — It takes about 6 weeks to heal, and you need a doctor specially trained in the technique.

Incision, drainage, closing of wound: In this technique, the cyst is drained, but it’s not left open.

Advantage — You don’t need to pack gauze because your doctor fully closes the wound right after surgery.

Disadvantages — You’re more likely to have more problems with the cyst down the road. It’s harder to remove the entire cyst with this method. It’s usually done in an operating room with a specially trained surgeon.’

Other surgical procedures include complete cyst and cyst wall excision along with the pilonidal sinus tracts, the use of fibrin glue, and taking (core out) only diseased tissue and the cyst out with punch biopsies.

Follow all of your doctor’s instructions about at-home care, especially if you need to remove and pack gauze. Other tips:

• Try to keep the area clean.
• Check for any signs of a new infection, such as redness, pus, or pain.
• Keep your follow-up appointments with your doctor so they can see how your cyst is healing.

A complete cure is possible, but remember that a pilonidal cyst may recur even if you had one surgically removed.

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why, what to do if it boils in the tank, how to prevent boiling

Contents

• Composition and tasks of the cooling system
• Antifreeze boiling symptoms
• Why does the coolant boil
• What happens if antifreeze boils
• Coolant boil prevention

Optimum temperature conditions for the operation of an internal combustion engine, even under severe operating conditions, are provided by the cooling system. Efficient heat removal from the cylinder block and parts of the piston group depends on the quality and properties of the antifreeze circulating in the circuit. Due to a malfunction of the system elements, as well as the poor quality of the additives, the coolant may boil. The consequences of overheating of the coolant are very serious for the motor. If the correct measures are not taken in a timely manner, the engine will lose power and fail. To restore the engine to working capacity, an expensive overhaul will be needed, so every driver must know how to control the coolant temperature and what to do if the antifreeze boils in the car.

Composition and tasks of the cooling system

To remove excess thermal energy from the engine, a liquid-type cooling system with a circulating coolant is provided. High-quality antifreeze evenly cools the power unit and releases heat into the atmosphere. In order for the cooling system to perform its functions, the following components are structurally provided:

• channels in the cylinder block forming a “cooling jacket”;
• pump for coolant circulation in the circuit;
• radiator for transferring heat from antifreeze to the atmosphere;
• fan to enhance air flow;
• interior heater heat exchanger;
• coolant temperature sensor;
• thermostat and expansion tank.

The operation of the cooling circuit is controlled by an electronic unit that receives signals from sensors and sends impulses to turn on the fan, thermostat heater and other additional devices. In good condition, the cooling system with circulating antifreeze successfully maintains the temperature regime of the engine, as well as automatic transmission (in some models).

In addition, thanks to the hot coolant, the air in the vehicle interior is heated in order to maintain a comfortable microclimate for the driver and passengers. Also, the coolant can be used in the machine to cool the air flow supplied to the turbine and exhaust gases in the recirculation device. For the power unit are provided:

• increased resource of trouble-free operation of the motor;
• economical fuel consumption;
• engine performance;
• maximum power;
• trouble-free vehicle operation in hot climates.

Given the importance of maintaining optimum engine temperature, vehicle owners should be aware of and identify the signs that antifreeze is boiling, and the negative effects it can have on the engine.

Symptoms of antifreeze boiling

If the driver timely detects the heating of the coolant to a critical temperature at which boiling begins, then the destruction of the cylinder block and deformation of the parts of the piston group can be avoided. To this end, in the technical documentation, automakers recommend that the driver constantly monitor the heating of the coolant in the cooling system while driving a car (on a trip). You can monitor the temperature in the circuit using the control device on the control panel. When the arrow or digital indicator tends to the red zone, this is the first sign of system overheating. When antifreeze boils, the driver must immediately stop the car and turn off the engine in order to understand the cause of the malfunction. It is unacceptable to operate a car with boiling coolant.

The operation of the instrument or the overheat warning lamp (on some models) depends entirely on the health of the temperature sensor installed in the cooling jacket of the cylinder block. If the control device on the control panel is faulty, then the driver must pay attention to the following signs:

• puffs of steam come out from under the bonnet;
• floating idle speed;
• power reduction, acceleration time increase;
• increasing noise while the engine is running at different speeds;
• sonorous (metallic) rumble;
• sudden stop of the engine;
• the composition has acquired a dark color;
• a white coating has formed on the electrodes of the candles or cracks have appeared;
• Antifreeze leaks from under the cylinder head gasket.

If the antifreeze boils and the engine heats up to a critical temperature, then when the car accelerates, the dynamics will deteriorate due to detonation (explosions in the cylinders). In the expansion tank, flakes and oil stains appear in the coolant due to engine oil entering the cooling circuit. Such a defect occurs due to the burning of the cylinder head gasket due to the heating of the antifreeze to the boiling point. If coolant enters the crankcase, foam and emulsion can be seen on the dipstick and on the bottom of the oil filler cap.

Why coolant boils

High-quality antifreeze designed for the car cooling system has a high boiling point of at least 110 °C. With this property, the coolant provides the optimal temperature regime for the operation of the power unit, including at full load. An increase in the temperature of the coolant to a critical value and boiling of antifreeze is possible for several reasons.

1. The radiator fan does not turn on due to a burned out electric motor, a relay or control unit malfunction.
2. The centrifugal pump (usually the bearing) is out of order and the coolant does not move in the cooling circuit, including through the radiator.
3. The thermostat is jammed, as a result of which the coolant circulates through the cooling jacket and the interior heater heat exchanger, therefore it cannot transfer heat to the atmosphere.
4. Formation of coolant leakage points. For each engine model, a certain amount of coolant is calculated, which is necessary for efficient heat removal. When the level in the system decreases, the antifreeze boils. A drop in the level is also observed as a result of the natural evaporation of the coolant, since the composition, in addition to alcohol, includes water.
5. Faulty sensor (relay) responsible for turning on the fan motor. Typically, the sensor is set to turn on at an antifreeze temperature of about 90–95 ° C. When the coolant reaches this temperature, the fan turns on and the heat exchange process in the radiator is more efficient.
6. Radiator honeycombs clogged with debris and dust. Air cannot pass freely through the cells, so the coolant does not cool completely when it circulates in the radiator. Clogging can occur due to the ingress of fluff, leaves, insects and dirt.
7. Violation of the circulation of the coolant due to an air lock. Air enters the system when the antifreeze is not properly filled into the circuit or when the coolant level in the expansion tank drops below the min mark.

Antifreeze also boils due to the difficult movement of the technical fluid in the circuit, due to the formation of sediment and plaque on the inner walls of the channels of the cooling jacket and nozzles. Such a malfunction occurs when a coolant with low-quality additives or a composition that is incompatible with the coolant poured into the system is added to the coolant circuit.

What happens if the antifreeze boils

The effects on the engine when the coolant reaches boiling point can be moderate to critical. It all depends on the timeliness of the actions of the driver. If the driver noticed in time that the indicator arrow on the dashboard went into the red zone, which means that the antifreeze had boiled, immediately stopped and turned off the engine, then moderate malfunctions are possible.

• Cylinder head gasket damage.
• Violation of compression in the cylinders due to deformation of the piston rings.
• Reflow piston mirror.
• Curvature of the BC head.
• Compression loss in cylinders.
• Defective intake and exhaust valves.

If the engine overheated due to the boiling of antifreeze and spontaneously stopped (jammed), then a major overhaul or a complete replacement of the power unit will be required to restore performance, if the repair is not economically feasible due to the high cost. Consequences for the motor as a result of critical overheating:

• piston burnout;
• fusion and rupture of compression rings;
• ingress of molten alloys on the cylinder walls;
• melting of the crankshaft liners;
• the appearance of cracks in the cylinder block;
• crankshaft jamming;
• piston damage to the cylinder block walls.

Determining the reason why the antifreeze boils in the tank, you can fix the problem and prevent an engine overhaul.

Prevention of coolant boiling

To prevent boiling of antifreeze and overheating of the power unit, the driver is advised to follow simple rules.

1. While driving, constantly monitor the coolant temperature using the indicator on the dashboard.
2. Check the coolant level in the expansion tank before every long journey and regularly when driving in town.
3. Pay attention to the presence of coolant under the vehicle after parking.
4. At the first sign of boiling of the coolant, turn off the engine and do not start until the cause of overheating is clarified.

Also, in order to prevent the antifreeze from boiling, only a certified coolant with high-quality additives recommended by the manufacturer should be poured into the system. We offer a wide range of high quality Sintec coolants of various types for gasoline and diesel engines of all vehicles. Having figured out why the antifreeze is boiling, and having eliminated the cause of the malfunction, you can choose to fill the car with a coolant that meets the requirements of the manufacturers and is characterized by a high boiling point.

How to avoid boiling antifreeze! Share life hacks

Why does antifreeze boil in a car? We understand in detail.

“Boiled” is a phrase of motorists, which is accompanied by the characteristic sound of bubbling coolant in the expansion tank. So why does antifreeze boil and how to solve this problem – read more in our article.

Why does the expansion tank boil?

Common causes:

– malfunction of the cooling fan;
– damage to the expansion tank or its cap;
– the thermostat does not open;
– air lock;
– pump malfunction;
– blown head gasket.

If the temperature sensor goes off scale, you need to stop, turn off the engine and make sure that the cooling fan is running. In case of malfunction, check the fuse (relay), replace if necessary. Inspect the fan connection chips for contact.

If the fan is working, check the expansion tank for damage and whether the cover valve is working. The lid should be opened carefully to avoid burns from antifreeze vapors. If there is a defect in the tank or a problem in the lid valve, they must be replaced.

#Important! The cap should be tightened on a cold engine until it stops! Do not overpressure, as the valve itself will relieve excess pressure. And do not twist loosely – the cover may fly off and the system will not hold pressure.

Another reason why antifreeze boils in the expansion tank is a thermostat malfunction. If the top hose is hot and the bottom hose is cold, the thermostat valve is most likely closed and not opening the large circle. In this case, the coolant moves only in a small circle. The thermostat should be replaced with a new one.

When the system is airy, the engine is worn out. To remove the air lock, it is enough to remove the hose from the throttle heating, as soon as air comes out and antifreeze flows, reattach it.

#Lifehack. To expel air from the system, you need to put the car on a hill at an angle, open the expansion tank and leave it to work for 5-10 minutes.

Pump wear also causes the antifreeze to boil. Among the causes of pump failure: violation of the integrity of the impeller blades, pulley play, bearing wear, improper belt tension. About what high-quality timing belts should be told earlier. We recommend installing a new pump.

White smoke from the pipe, streaks or wet deposits on the engine under the cylinder head, a characteristic smell of exhaust gases in the coolant indicate that the cylinder head gasket is blown. The part is to be replaced.

Why does it boil at 90°C?

Root causes:
– malfunction of the cover of the expansion tank;
– low-quality coolant.

Below atmospheric pressure, the boiling point drops. If the cap of the expansion tank is defective, the pressure in the system drops, which is why antifreeze boils at 90 degrees. The problem is solved by replacing the cover.

Poor quality antifreeze contains additives that precipitate and cause corrosion and malfunctions in the cooling system. This can lead to overheating and overhaul. We advise you to fill in high-quality coolant made in accordance with GOST 28084-89and replace within the manufacturer’s recommended intervals.

#Lifehack. Since it is allowed to continue driving after the engine has cooled down, you can turn on the stove at maximum speed and temperature. This will allow the engine to cool faster and enable you to get to your destination.

Why is it boiling in the radiator?

The main reason is poor-quality coolant, which gives off a strong smell of alcohol. The methanol, which is part of it, during evaporation creates an excess pressure in the system. Hence, boiling, the formation of microcracks in the pipes, gusts in weak connecting nodes, for example, the radiator neck or from under the pipes, loosely crimped with clamps. Silicone pipes have proven themselves, withstanding pressure up to 10 atm.

Boils and throws away. What does it mean?

If the antifreeze boils and is thrown out of the expansion tank, the problem is in the cylinder head gasket.