Pyrexia: The Common Fever Explained

In the mid-1800s, German doctor Carl Reinhold August Wunderlich formulated his pioneering work in clinical thermometry and postulated that 98.6°F or 37.0°C be regarded as normal body temperature. For nearly a century, doctors accepted this as the upper limit of normal temperature, and anything beyond that was regarded as a fever. Recent research, however, suggests that normal temperature can range between 97.5°F and 98.9°F (36.4°C and 37.2°C), and any reading beyond this should be considered to be a fever.

What is Pyrexia?

Fever, referred to as Pyrexia in medical terms, is a condition in which the patient's body temperature has risen above the normal range. Pyrexia can be a symptom of several different conditions. However, it is often the body's first line of defence in combating infections.

Dr. Manoj Ranka, Consultant, Max Super Speciality Hospital, Saket says fever is when your body raises its temperature above normal for a long time. Your body temperature fluctuates throughout the day; it tends to be lower in the morning and higher in the afternoon. Medically, you are considered to have a fever when your body temperature crosses 100.4 degrees Fahrenheit (38 Celsius).

Types of Pyrexia

The nature of the Pyrexia can often give the doctor a clue about the cause. It is important to keep a record of the elevations in body temperature if you are availing of in-home care.

• Intermittent Fever - Intermittent Fever is a condition when the patient develops a fever, typically at night, but the temperature returns to normal each day.
• Remittent Fever - Remittent fever is when the body temperature remains elevated with fluctuations but does not return to normal for 24 hours.
• Hectic Fever - Hectic fever is characterised by a considerable variation in the temperature readings between the peak and the lows and is often accompanied by chills and sweats.
• Continuous Fever - Continuous or sustained fever is a prolonged elevation in body temperature with little change in 24 hours.
• Relapsing - Relapsing fever is an intermittent fever that relapses or causes an elevation in body temperature after days or weeks of returning to normal.

What are the causes of Pyrexia?

The hypothalamus gland is located in the brain and regulates body temperature. When the human body detects a disease, the immune response prompts the hypothalamus to raise the temperature, causing a fever. This complex physiological process increases the core heat and creates conditions in which the body's immune system may fight the disease or the pathogen causing the infection.

Some of the common causes of fever include –

• Viral infections such as the common cold, influenza, rubeola virus, norovirus, enterovirus, Hepatitis B, HIV, etc., can cause fever.
• Most bacterial infections, such as Shigella, E.coli, Salmonella, etc., cause fever.
• Extreme dehydration and heat exhaustion can also spike a fever.
• Some cancers, such as Hodgkin's lymphoma and non-Hodgkin's lymphoma, acute myeloid leukaemia, hairy cell leukaemia, renal cell carcinoma, glioblastoma etc., can cause recurrent fever.
• Drug-induced fevers can be a response to the medication or can indicate an allergic reaction.
• Fevers are a common reaction to vaccines such as DPT or the COVID-19 vaccine.
• Fever can also be a response to blood transfusion.

What are the symptoms of Pyrexia?

A rise in body temperature is usually referred to as Pyrexia. It can be measured by using a clinical thermometer. Pyrexia is often accompanied by other symptoms that help diagnose the underlying cause. These include -

• Hot skin or flushing of the skin
• Elevated heart rate or palpitations
• Chills, shivering or shaking
• Muscle aches
• Joint pains
• Fatigue or dizziness
• Headaches
• Dehydration
• Excess sweating
• In the case of extremely high temperatures, confusion, disorientation, or hallucinations may occur.
• In babies and infants, fever may be accompanied by fussiness or crying with fever, diarrhoea, and (in rare cases) seizures.

How to diagnose Pyrexia?

In most cases, Pyrexia is a symptom of an underlying cause. To diagnose the condition, your doctor at Max Healthcare will do a physical exam and learn more about your or your child's medical history. The accompanying symptoms, such as earache or chills, may give the doctor a starting point for the diagnosis. If the doctor suspects infection or diseases such as Malaria or Typhoid, they may recommend tests to confirm the diagnosis.

What are Pyrexia treatment options?

Pyrexia, or fever, is the body's defence mechanism that helps fight infection and diseases. Treatment options often address the underlying issue, including keeping the fever from going too high. Your doctor at Max Healthcare may recommend the following treatments -

• Medicines - Antibiotics are often prescribed to treat bacterial infections causing fever. In the case of mild viral infections, the doctor may recommend rest and fluids, but in severe cases, anti-viral and immunity-boosting medicines are recommended. Specific drugs to combat diseases like malaria, typhoid, gastroenteritis, etc., may be prescribed after a diagnosis is established. Usually, OTC medicines like Nonsteroidal anti-inflammatory drugs (NSAIDs), aspirin, acetaminophen, and ibuprofen are prescribed to help relieve associated symptoms.
• Fluids - Dehydration and loss of electrolytes are real concerns when the body temperature rises. Increase intake of clear warm fluids if you are running a fever.
• Diet - Soft, easily digestible foods are recommended to keep the load off the digestive system and to ensure the supply of essential nutrients.
• Rest - It is essential to support the body's natural healing process by getting lots of rest.
• Supportive therapy – To reduce very high temperatures, the doctor may recommend applying a damp cloth to the forehead and wrists or wiping the body with a warm, damp towel.

What are the risk factors for Pyrexia?

Any bacterial or viral infection poses a risk factor for developing Pyrexia or fever. The body's natural immune system can combat most infections before they present any systems. However, patients with weakened immune systems due to conditions like diabetes, chronic lung infections, cancer, etc., are at a higher risk of developing a fever.

The risks of developing fever are greater in these cases –

• Being in close contact with a patient who is suffering from an infectious disease
• If you are suffering from dehydration, exhaustion, or nutrient malnourishment
• If you have a compromised immune system due to a pre-existing condition
• If the patient is a child or an elderly person. In both cases, the immune system is weak and unable to work, like in the case of a normal adult.

What are the complications associated with Pyrexia?

Prolonged high-grade fever (over 104°F or 40°C) can lead to many complications, such as -

• Seizures - Febrile seizures accompanied by high fever are a complication developed by children under the age of 5 years. Adults, too, may suffer from seizures. To prevent this, high fever must be reduced by sponging the body and administering medication recommended by the doctor.
• Brain damage - Very high fever can cause confusion, disorientation, and hallucinations, and in rare cases, can lead to brain damage.
• Coma and death - If high-grade fever is left untreated, it can cause several complications, including coma and death.

Foods that can help with Pyrexia

Pyrexia puts a great deal of strain on the digestive system. It is often accompanied by nausea, vomiting, and/or diarrhoea. Your diet during any episode of fever should support your recovery. Here are some foods that are recommended during fever.

• Fluids - Fluid-rich foods like warm herbal teas, broths, light soups, coconut water, and fresh juices.
• Fresh fruits - Fruits rich in Vitamin C contain antioxidants that boost the immune system. Adding berries, oranges, apples, melons, and seasonal fruits to your diet is a good idea. Avoid canned and high-sugar or preserved fruits.
• Proteins - To supplement the body's protein needs, add scrambled eggs, low-fat chana or cottage cheese, dals or khichdi to your meals.

Foods to avoid – It is best to avoid heavy foods that are difficult to digest. Red meat, and dairy products, including cream, cheese, and milk, are best avoided. It is also a good idea to abstain from alcohol or caffeine consumption during fevers. Replace them with herbal teas and warm broths. Avoid heavy protein foods like legumes, full-cream cheeses or paneer, and heavy meat.

What is the first-aid treatment for Pyrexia?

When you or someone you care for experiences an elevation in body temperature, it is important to use a clinical temperature and record the readings every 2 hours. In case of a high fever, contact your doctor at Max Healthcare. The first aid that you can provide for immediate relief includes the following -

• Administering OTC medications such as acetaminophen or aspirin (as the patient about drug allergies or contraindications, if any)
• Use a warm damp cloth to sponge the body or apply it on the forehead to reduce the temperature.
• Offer ORS if fever is accompanied by vomiting and excess fluid loss.
• Offer a rug or blanket to keep the patient warm if they are experiencing chills or shivering.
• If the patient is experiencing seizures, turn them to the side and seek immediate medical attention.

How can Pyrexia be prevented?

Pyrexia or fever can be prevented by keeping the body healthy and disease free. A robust immune system is the result of good dietary and lifestyle habits. High fevers should be treated immediately, but in most cases, a low-grade or mild fever will pass with supportive care and rest. In cases of serious infection or diseases, the underlying cause must be addressed.

When should you need medical attention?

In most cases, pyrexia is beneficial, causes no problems, and helps your body fight off infections naturally. Fever normally clears up on its own after having run its course of fighting harmful bacteria and viruses in 2-3 days. As long as your temperature doesn’t cross 103 degrees Fahrenheit (39.4 Celsius) short lasting you don’t need medical attention. If it does cross 103 degrees persistent beyond 3-4 days, then consult your doctor immediately.

Infant

Any spike in a fever for a child less than three months of age should be a sign that you should contact the paediatrician immediately. Signs to look out for include -

• Fussiness, relentless crying
• Lack of urination or bowel movements for over 4 hours
• Rash
• Any sign of weight loss, sluggishness, clammy skin
• Febrile seizures

Children

Children up to the age of 5 years can experience febrile seizures when the fever is very high. Here are some signs that should prompt you to seek immediate medical attention.

• Sluggishness, unusual lethargy
• Lack of appetite, refusing food or the bottle
• Relentless fever
• Any sign of pain, distended abdomen
• Diarrhoea or severe constipation
• Nausea or vomiting over a long period
• Dizziness, lack of consciousness

Adults

Adults can keep a record of their fever and allied symptoms and seek medical help if the following symptoms are observed.

• High, persistent fever
• Severe chills or shaking
• Disorientation and hallucination
• Nausea or vomiting over a long period, signs of dehydration
• Fainting, lack of consciousness
• Inability to swallow, speak, or move
• Chest pain, trouble breathing
• Unrelenting headache

Pyrexia is unpleasant and tiring; there’s no doubt about it. The best way to treat it is to take plenty of rest and allow it to run its own course. Take your temperature every hour and make a record. If your fever does cross 103 degrees Fahrenheit (39.4 Celsius) or If you are unsure about the cause of your fever or Pyrexia, it is important to consult an Internal Medicine doctor at Max Healthcare. Max Hospitals have some of the best medical testing facilities, experienced doctors and patient care systems in the country.

ALERT:-

High fever in children below 3-4 years needs to be brought down urgently as it can cause Febrile Seizures. So immediately, start doing cold sponging (entire body) and consult your pediatrician/doctor at the earliest.