PROLOGUE

This  blog is all about FEVER'S ROLE IN INFECTION AND INFLAMMATION  and a  fulfillment of  the requirements in N204- Advance Pathophysiology  under Professor Rita Ramos.


Please note that proper order of topics is in reverse order. Later posts  comes first . In other words  topic 1 is at the bottom of the page and topic 5 is at the top most part of the page . Please be patient to scroll down and enjoy learning. YOu can also check on the topics through archives on the right.


PS


Don't forget to play Elvis video at the bottom of the blog page or the 1st post. It will surely set the mood while  reading . The lyrics are kind of related to the topic. Enjoy 

REFERENCES

http://www.humanillnesses.com
http://en.wikipedia.org

http://www.pathophysiology1.com/

Pathophysiology and Management of Fever by S.Dalal, MD, and D.Zhukovsky, MD, FACP
Blackwell's Dictionary of Nursing. (1994). Oxford: Blackwell Science Ltd

.

Bullock, B.L.; Henze, R.L. (2000). Focus on Pathophysiology. Philadelphia: Lippincott.

Dalal, S.; Zhukovsky, D.S. (2006, January). Pathophysiology and Management of Fever. The Journal of Supportive Oncology (www.SupportiveOncology.net) , pp. 9 - 16.

Infection. (2011, June 8). Retrieved June 20, 2011, from Wikipedia website: www.wikipedia.com

Morton, R.S.; S. Rashid. (1997, June). Role of fever in infection: has induced fever any therapeutic potential in HIV infection? Retrieved June 25, 2011, from PubMed Central: 

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1195825/pdf/genitmed00003-0058.pdf

Ocampo-Balabagno, A.V.; et. al. (2006). Pathophysiology. Quezon City: University of the Philippines Open University.

Price, S. A.; Wilson, L.M. (1992). Pathophysiology Clinical Concepts of Disease Processes. St. Louis: Mosby Year Book.

Story about Fever's role in infection and inflammation

SUGATAN 

Nurse Ann is working as a community health nurse in one of the rural area. One day, AlingNena came to the center with her youngest daughter.

AlingNena: Nurse pwede mo ba akong tulungan? (Nurse, can you help me?)

Nurse: Ano po ang maitutulong ko? (What can I do to help you?)

AlingNena: Ito kasing anak ko, nadapa nung isang linggo, nilangaskonangangdahonngbayabasangsugatniyaperongayonnilalagnatnasiya. ( My daughter accidentally stumbled last week, I already cleansed it with guava leaves but now she already have fever)

Nurse: Tignan po natin ang sugat at papakita din natinkaydoktora. (Let us see the wound and we will ask the doctor to see the wound )

After the consultation with the doctor, the nurse assessed the wound and preparethe materials for dressing.

While doing the dressing:

AlingNena: Bakit kaya siya nilagnat? Para sugat lang na manyan. (Why did she have fever? It’s only wound. )

Nurse: Mukha po kasing na impeksiyon na ang kanyang sugat. Ang mga mikrobyo po kasi ay may nilalabas na parang kemikal na tinatawag na exotoxin namagiging dahilan para lagnatin ang isang tao. At hindi lang na man po dahil lang sa impeksiyon, minsanang sugat mismo ay maaaring maging dahilan nglagnat. Dahil nga po na sugatan tayo, ito ang magiging daan para sa mga mikrobyo para makapasok sa ating sistema. At bilang dipensa, nagpapadala po ang ating katawan ng mga panlaban (neutrophil at macrophages) para patayin ang mga mikrobyo. At ito ay maglalabas ng kemikal ng pwedeng maapektuhanang parte ng ating katawan na nagbabalanse sa ating temperature ng magiging sanhing lagnat. Ito po ay isang normal  na eaksiyon ng ating katawan.

                        (This is already an infected wound. Infectious agents produce chemicals called exotoxin  which can be the cause of fever. Besides, it’s not only the infection, sometimes a wound can cause fever. Since we have tissue injury, it can be the mode of entry of the microorganism to invade our system. As a defense mechanism, our body send agents (neutrophil and Macrophages) to kill the microorganism. And this can produce chemicals that will affect the organ which controls our temperature which will be the reason for the increase of body temperature. And this is a normal reaction of our body.

AlingNena: Galing naman palang katawan natin at merong sariling panlaban sa mikrobyo. (Our body is good because it has its own defense mechanism.)

Nurse: Tama po kayo diyan. (You are right)

After dressing and all the instructions, Aling Nena and her daughter left the center.

TEACHER FEVER

Clinical Instructor Melvin was assigned at the Surgical Unit of Outpatient Department of MCU Hospital. He is teaching the 2^nd year students of Nursing during their summer. One of the students was assigned to take the vital signs of the patient. During vital signs taking, CIMelvin noticed that the student is taking the temperature by touching the forehead of the patient and estimating the temperature in the vital signs sheet. After doing the vital signs, CI Melvin called the attention of the student.

CI: did you take the complete vital signs of the patient?

Student: Yes, Sir

CI: How did you take the temperature of the patient?

Student: I touched his forehead because I cannot find any thermometer.

CI: Why temperature taking is part of the vital signs of a patient?

Student: Because it will tell us if we have fever?

CI: It can be. Body temperature normally relates to the temperature deep inside of our body. There are some diseases that is accompanied by fever and you can also monitor the course of the disease.

Student: Does it mean that if a patient has fever, they already have a disease?

CI: Not all the time. For example your last patient, what is his case?

Student: He is working in a factory and accidentally, his finger was caught by the mixer. It’s good that he did not lose his finger.

CI: That’s it. It can be caused by a local tissue injury and microorganisms invade our body, our body will send will send neutrophil and monocyte that later will transform to macrophages to perform phagocytosis then produce pyrogen and affect the temperature regulator center, which is the?

Student: Hypothalamus of the brain?

CI: Correct. So, do you think is it necessary to take the temperature accurately?

Student: Yes, to be able to create a good care plan for our patient.

CI: So, what do you need to do now?

Student: Look for a thermometer and take the temperature of the patient.

Articles and Researches related to Fever's role in Infection and Inflammation

Enjoy reading the following articles, post and researches about Fever's role in Infection and Inflammation. We hope you find them beneficial to our study.


Study Finds Fever May Lead to Improved Behavior in Children with Autism Spectrum Disorders


Role of Fever in nfection:has induced fever in any therapeutic potential in HIV infection



How Baby Fever spreads through Offices


Fever Myths and Facts
Misconceptions about the dangers of fever are commonplace. Unwarranted fears about harmful side effects from fever cause lost sleep and unnecessary stress for many parents. Let the following facts help you put fever into perspective:
MYTH: All fevers are bad for children.
FACT: Fevers turn on the body’s immune system. Fevers are one of the body’s protective mechanisms.
Most fevers are good for sick children and help the body fight infection. The exception is babies less than 3 months of age. They should be seen by a healthcare provider right away. Use the following definitions to help put your child’s level of fever into perspective:


100°F to 102°F Low-grade fever: Beneficial. Try
(37.8°C to 39°C) to keep the fever in this range.

102°F to 104°F Moderate-grade fever: Beneficial.
(39°C to 40°C)

Over 104°F High fever: Causes discomfort, but
(40°C) is harmless.

Over 105°F High fever: Higher risk of
(40.6°C) bacterial infections.

Over 108°F Serious fever: The fever itself can
(42°C) be harmful.

MYTH: Fevers cause brain damage or fevers over 104°F (40°C) are dangerous.
FACT: Fevers with infections don’t cause brain damage. Only body temperatures over 108°F (42°C) can cause brain damage. The body temperature goes this high only with extreme environmental temperatures (for example, if a child is confined in a closed car in hot weather).
MYTH: Anyone can have a febrile seizure (seizure triggered by fever).
FACT: Only 4% of children have a febrile seizures.
MYTH: Febrile seizures are harmful.
FACT: Febrile seizures are scary to watch, but they usually stop within 5 minutes. They cause no permanent harm. Children who have had febrile seizures do not have a greater risk for developmental delays, learning disabilities, or seizures without fever.
MYTH: All fevers need to be treated with fever medicine.
FACT: Fevers need to be treated only if they cause discomfort. Usually that means fevers over 102°F or 103°F (39°C or 39.4°C).
MYTH: Without treatment, fevers will keep going higher.
FACT: Wrong. Because of the brain’s thermostat, fevers from infection top out at 103°F to 104°F (39.4°C to 40°C). They rarely go to 105°F or 106°F (40.6°C or 41.1°C).
MYTH: With treatment, fevers should come down to normal.
FACT: With treatment, fevers usually come down 2° or 3°F (1.1° or 1.7°C).
MYTH: If the fever doesn’t come down (if you can’t “break the fever”), the cause is serious.
FACT: Fevers that don’t respond to fever medicine can be caused by viruses or bacteria. Whether the medicine works or not doesn’t relate to the seriousness of the infection.
MYTH: If the fever is high, the cause is serious.
FACT: If the fever is high, the cause may or may not be serious. If your child looks very sick, the cause is more likely to be serious.
MYTH: The exact number of the temperature is very important.
FACT: How your child looks is what’s important, not the exact temperature.
MYTH: Temperatures between 98.7°F and 100°F (37.1°C to 37.8°C) are low-grade fevers.
FACT: These temperatures are normal variations. The normal temperature changes throughout the day. It peaks in the late afternoon and evening. A low-grade fever is 100°F to 102°F (37.8°C to 39°C).
MYTH: Feed a cold, starve a fever.
FACT: This old saying should be ignored. Fevers cause the body to lose fluids through sweating and breathing. Children with fevers need lots of fluids. Children with a fever may or may not be hungry for food. If they are hungry, offer the food that they choose. It is helpful to do so.
Reading Temperatures
· A reading of 99.4°F (37.4°C) is the average rectal temperature. It normally can change from 98.4°F (36.9°C) in the morning to a high of 100.3°F (37.9°C) in the late afternoon.
· A reading of 97.6°F (36.5°C) is just the average oral temperature. It normally can change from a low of 95.8°F (35.5°C) in the morning to a high of 99.5°F (37.5°C) in the late afternoon.

Diagram of Fever's role in Infection and Inflammation

Fever is a healing response. It is one of array of host defence responses (STRESSRESPONSE) to invasion of body microbes. A fever can be caused by many different conditions ranging from benign to potentially serious (STRESSORS). Most often, they are bacteria and their endotoxins, viruses, yeasts, spirochets, protozoa, immune reactions, several hormones, medications, and synthetic polynucleotides. These substances are commonly called exogenic pyrogens. Cells stimulated by exogenic pyrogens form and produce cytokines called endogenic pyrogens. These are produced by the host in response to INFECTION, injury, INFLAMMATION, or antigenic challenge. Endogenic pyrogens centrally affect the thermosensitive neurons in the preoptic area of the hypothalamus increase the production of heat and decrease in heat loss. The body temperature increases until it reaches the set point. This information is transferred by temperature of blood that flows around the hypothalamus. The decrease of temperature is controlled by activation of mechanisms regulating increased outcome of heat to the surrounding area (NEGATIVE FEEDBACK MECHANISM). Increased outcome continues in favourable case until the new equilibrium is achieved (HOMEOSTASIS). There are arguments for and against the usefulness of fever, and the issue is controversial.

Fever slightly increases immune reactions, increases chemotactic, phagocytic, and bactericidal activity of polymorphonuclear leucocytes. Up to certain value, it stimulates the processes of antibody production.

Concomitantly, it slows down the proliferation of microorganisms. Increased body temperature causes a decrease in the amount of plasmatic iron, zinc, and copper. This decrease is not favourable for the growth of microbes. High temperature causes destruction of lysosomes and the whole cells. This is a way by which the body defends itself against microbes but also against replication of viruses. The increased production of interferons also acts against viruses.

In general, fever is considered to be a pathological reaction. However, it belongs to compensatory mechanisms and has important roles in defense processes

The role of Fever in Infection and Inflammation

Fever or hyperthermia is the elevation of body temperature above normal. A normal healthy adult have a normal body temperature ranging from 36.5 C to 37.5 C. Our body temperature is controlled by the hypothalamus. Fever is considered to be the hallmark sign of infection   Fever is the temporary increase in the body's temperature, in response to some disease or illness. Much like other fundamental aspects of human biology, core body temperature is regulated closely by intricate control mechanisms, involving a complex interplay of autonomic, endocrine, and behavioral responses. The hypothalamus is central to this process, functioning as a thermostat, controlling thermoregulatory mechanisms.

Fever is an almost universal phenomenon of illness, particularly local inflammatory processes, noninfectious as well as infectious. It is considered a defense against disease. High body temperatures intensify the effect of interferons. A high body temperature speeds up the body’s reactions and may help the body tissue repair themselves more quickly. It is thought to be caused by the release of endogenous pyrogens from macrophages and possibly from eosinophils, which are activated by phagocytosis, endotoxins ,immune complexes, and other products. Thus, fever help in the healing process. 
The role of fever in inflammation and infection is it acts as the "alarm" for us human to know that something is not right with our body. It signals us that there is already a pathogen inside our body. And that our body is already fighting it. 

In theory, fever can aid or help host defense. Fevers may be useful to some extent since they allow the body to reach high temperatures, causing an unbearable environment for some pathogens. Also, White blood cells rapidly proliferate due to theThough fever may be categorized as a symptom, it also act as a "helper", that is its role.

The presence of inflammation does not always correlates with the presence infection. Infection happens when there is a viable organism capable of causing a disease in a person. There are several factors that should be taken in consideration in the invasion of infectious agents to a host. Such factors like virulence of organism, number of invading microorganisms, the ability of the host to resist infection, the host's defense mechanism and the presence of special types of barriers, contribute in the causation of infection..

The role of fever in inflammation and infection is actually unclear. Although it is obvious that fever can cause considerable discomfort and even death if very high and uncontrolled, several studies have shown that fever can actually be quite beneficial at certain points. According to our module, an increase in body temperature would mean an increase in the metabolism therefore causing the bone marrow of the body to produce more antibodies than usual at a faster rate. Other studies suggest that some microorganisms/viruses cannot thrive on high temperature environment thus, preventing infection. Also, fever serves as an indicator that our body's immune system is working for us and it is usually a determining factor for people to seek medical help.

Therefore, fever is one of the defense mechanisms that the body utilizes to warn on possible threats of impending disease. And this is why fever plays an important role in the process of inflammation and infection

Fever in inflammation and infection and Modules 1-3 of Advanced Pathophysiology by University of the Philippines Open University

Module 1 (Adaptive and Regulatory Mechanism)

Homeostasis refers to the self regulating process of the body and the maintenance of these process in equilibrium. 

Temperature is ultimately regulated in the hypothalamus. The normal temperature is 36.5–37.5 °C, whether the caused of change in temperature is inside or outside of the body, the body will always do something to maintain its homeostasis. 

Example of this is the negative feedback mechanism. When the set point is raised, the body increases its temperature through both active generation of heat and retaining heat. Vasoconstriction both reduces heat loss through the skin and causes the person to feel cold. If these measures are insufficient to make the blood temperature in the brain match the new setting in the hypothalamus, then "shivering" begins in order to use muscle movements to produce more heat. When the fever stops, and the hypothalamic setting is set lower; the reverse of these processes (vasodilation, end of shivering and nonshivering heat production) and "sweating" are used to cool the body to the new, lower setting. From Figure 1-4 (Effect of temperature change on the negative feedback mechanism), we can clearly see what shivering and sweating roles are. 

Adaptive and regulatory mechanisms, we've learned that our body is dynamic and is always in adjustment with its environment to maintain balance. Although we agree that our bodies are almost the same in terms of its composition and structures, different intrinsic and extrinsic factors differentiates us from the rest of the population. Balance starts from the cellular level, and we've learned that healthy cells means a healthy body. Our body is incredible, it can adapt to various situations. It has its own "self-government" with its own rules and regulations and all of the cells have their designated functions. Several regulatory mechanisms govern our bodies so that we maintain homeostasis. It is amazing to know that when our bodies are under attack, i.e. infection or inflammation, negative feedback mechanisms take effect and the brain signals the body to take necessary actions/processes to fight the infection and repair the damage. Having an understanding about this mechanisms can help us better understand how our bodies work (how inflammation works, its functions, it benefits to the body) and thus, adapt our actions/interventions to support/promote the body's natural ways of healing/repairing itself.

Module 2 (Cellular Functions: An Overview)

In this module, we learn the cellular changes and aging. We learn that thinning of the epithelium and decreased in subcutaneous fat could affect regulatory of temperature. Decreased in subcutaneous fat lessen the skin's insulating ability. This will lessen the affect of "shivering". Also, aged cells decreased the number of sweat glands in the skin. Thus, decreasing the ability to eliminate heat through evaporation. I think this will lessen the effect of "sweating".

With this data, we can tell that cell aging thus affect the process of conserving and eliminating heat. 

Module 3 (Alterations in Protective Mechanism: Inflammation and Infection)

Fever arise when there is inflammation and infection. Thought in some cases, there are no fever present. The mechanism of fever is a defense reaction by the body against infection. When bacteria or viruses invade the body and causes tissue injury, one of the immune system's response is to produce pyrogens. A pyrogen is a substance that induces fever. These can be either internal (endogenous) or external (exogenous) to the body. The bacterial substance lipopolysaccharide (LPS), present in the cell wall of some bacteria, is an example of an exogenous pyrogen. These chemicals are carried to the brain, where they disturb the functioning of the hypothalamus. 

The cellular response to injury has again proven to us the beauty and complexity of the human body. The module stated some examples of protective mechanisms used by the body to guard itself from harm. Although most of the examples given were trivial,  we were actually surprised to know that fever can actually be a form of protective mechanism. Before, all I know is that fever is the universal sign of infection and it signal us that something is wrong with our body; that our immune system is working and defending us from "invaders". In my opinion, the reason perhaps why phagocytic cells release endogenous pyrogens during inflammation/infection is to signal the body that they need back-up. Let me explain it using this analogy:

Our body is like a country; with the brain as its president. The cells are his constituents. The organs are like his cabinet secretaries. Now, during an invasion (infection) the local police(sensory neurons) will now try to suppress the invasion locally (local inflammation). With the help of the local police (phagocytic cells) on site, they will try to kill the invaders (bacteria). However, the invaders are too strong for the local police, therefore, the local police will send signal (endogenous pyrogens) to the president, through one of his office (the hypothalamus) to ask for back-up. What the president would do then is to order his secretary of defense (immune system) to send and produce more back-up as well as contingency measures(thru the bone marrow creating more cells) to repair the damage done. The secretaries (body organs) complies with the order by increasing their metabolic rate (to produce the needed "soldiers" and "materials" as well as to speed up transport) and thus produce heat which in turn causes fever.

What is the role of fever in inflammation and infection?