FEVER

 WHAT IS FEVER?

Fever is the body temperature rise above the normal circadian variation due to changes in the thermoregulation center located in the anterior hypothalamus. Normal body temperature can be maintained when there are changes in environmental temperature, because of the ability of the thermoregulation center for megatur balance between heat produced by the network, particularly by muscle and liver, with heat loss. In the state of fever, the balance shifts to an increase in body temperature. 


Patient's temperature is usually measured by mercury thermometer and place of uptake may be in the axilla, oral or rectal. Normal body temperature ranges between 36.5 -37.2 ˚C. Subnormal temperature below 36 ˚ C. Fever is generally defined temperature over 37.2 ˚ C. Hiperpireksia is a condition that increases the body temperature to as high as 41.2 ˚ C or more, whereas hypothermia is a state of body temperature below 35 ˚ C. Usually there is a difference between the temperature measurements in the axilla and oral or rectal. Under ordinary circumstances these differences range from about 0.5 ˚ C, rectal temperature higher than oral temperature.

FEVER MECHANISM

In the evolution of life, the body has developed a system powerful to defense against infection and elevated body temperature which provides an optimum work opportunities for system of body defense. Substances  cause fever is called pyrogens, either exogenous or endogenous. Exogenous pyrogens originating from outside the host (host), while the endogenous pyrogens are produced by the host, usually as a response to early symptoms are usually triggered by infection or inflammation. Examples of exogenous pyrogens are microorganisms and their products. In general, an exogenous pyrogen work mainly by inducing the formation of endogenous pyrogen.
Endogenous pyrogens are polypeptides produced by host cells, mainly monocytes and macrophages. These polypeptides called cytokines. In addition monocytes and macrophages, cytokines are also produced by lymphocytes, endothelial cells, hepatocytes, epithelial cells, keratinocytes and fibroblasts. Pirogenik cytokineslimfotoksin), interferon α (IFNα) and interleukin 6 (IL-6). Endogenous pyrogens, which produced either systemic or local, managed to enter the circulation and causing fever on thermoregulation in the hypothalamus of the central level.  IL-1β is a major, IL-1α, tumor necrosis factor α (TNFα), tumor necrosis factor β (TNFβ,

Body temperature is controlled by the hypothalamus. Neurons in the anterior hypothalamus praoptic and posterior hypothalamus receive two kinds of signals, one of which reflects the peripheral nerve receptors for warm and cold, other than the blood temperature of the wet area. Both these signals are integrated by hypothalamic thermoregulation center to maintain a normal temperature. In addition, there are groups of neurons in the hypothalamic preoptic / anterior supplied by a rich vascular network and highly permeable, with blood-brain barrier function is reduced. Specialized vascular tissue is called Organum vasculorum laminae terminalis (OVLT). OVLT endothelial cells will release the metabolites of arachidonic acid when exposed to endogenous pyrogens from the circulation. Metabolites of arachidonic acid, which is largely prostaglandin E2 (PGE2), and then allegedly diffuses into the hypothalamic preoptic area / anterior and sparked feverish. It is possible when PGE2 or other products of arachidonic acid induces a second messenger (second messengers) such as cyclic AMP, which in turn raise the point of thermoregulation has been defined. PGE2 is a derivative of arachidonic acid is the most potent causes fever when injected directly into the hypothalamus and is believe increase at the point of thermoregulation has been defined. With "thermostatic settings" new, higher, signals leading to various efferent nerves, especially the sympathetic fibers that inervates peripheral blood vessels, which in turn sparked facilitate vasoconstriction and heat conservation .
Thermoregulation center also sends signals to the cerebral cortex, triggering changes in behavior such as seeking a warmer environment, clothing, a special attitude. With shunt from peripheral blood, as well as behavioral changes, body temperature is usually increased by 2 to 3 ˚ C; if the hypothalamus requires more heat, shivering is also triggered to increase heat production. The combination of heat conservation and heat production increase continues until the temperature of blood supplying the anterior hypothalamus neurons in accordance with the "point of setting" a new one. At that point, the hypothalamus maintain the temperature of the new fever.

TYPES OF FEVER

Some types of fever that may be encountered include:

1. Septic fever: In this type of fever, body temperature gradually rose to very high levels at night and fall back to levels above normal in the morning. Often accompanied by complaints shivering and sweating. When high fever is down to normal levels are also called fever hectic.
2. Remittent Fever: The type of remittance fever, body temperature can go down every day but never reached normal body temperature. Recorded temperature differences that might be achieved two degrees and not for the difference in temperature recorded in septic fever.
3. Intermittent fever: On the type of intermittent fever, body temperature dropped to normal levels for several hours in one day. When fever like this happens once every two days called tersiana and when there are two free days between the two attacks of fever called quartana.
4. Continuous fever: The fever of this type of temperature variation during the day did not differ by more than one degree. At the level of continuous high fever once called hyperpireksia.
5. Cyclic fever: In this type of fever increases the body temperature for several days, followed by a period free of fever for several days and then followed by an increase in temperature as before.

SYMPTOMS WHICH ACCOMPANY FEVER

Many of the symptoms that accompany the fever, such as symptoms of back pain, myalgia comprehensive, artralgia, anorexia and somnolen. Moreover, it can also appear cold symptoms (chills) that cold feeling that emerged in most circumstances a fever, symptoms of chills (rigors), which is more intensive cold symptoms accompanied by piloereksi (goose flesh) and teeth chattering and shaking. Changes in mental status and convulsions often occur in patients whose age was very young or very old and in patients with dementia, heart failure and chronic renal failure. These changes can happen progressively starting from irritability, delirium until somnolen real. Febrile seizures in infants and toddlers are typically occurs in fever. Fever can also spark a seizure in patients with adult epilepsy.

FEVER DIAGNOSTIC

Basically, to achieve the required accuracy of diagnosis of the cause of fever among other things take care of patients medical history, conducting physical examinations as possible, observation and evaluation of travel sickness and other supporting laboratory examination appropriately and holistically. A careful anamnesis is very important. Anamnesis of a history of contact with animals, poisonous fumes, which Potential infectious organisms, or with substances that may be the antigen, or contact with other people who suffer from heat illness or infectious disease at home, at work or school. Unusual hobbies, a tendency to eat, and pets should be determined. Our attention should also be directed at the use of tobacco, marijuana, intravenous drugs or alcohol, trauma, animal bites and bites of fleas or other insects, history of transfusion, vaccination, drug allergy or hypersensitivity. A careful family history should include a history of tuberculosis disease in family members, heat disease or other infectious diseases, arthritis or collagen disease. Pattern / type of fever should also be considered. Pattern of widespread use of antipyretics, glucocorticoids, and antibiotics can alter the pattern of fever that classic fever patterns are not visible. A type of fever can sometimes be associated with a particular disease, such as the type of intermittent fever for malaria. A patient with symptoms of fever may be associated with an immediately apparent reason, such as abscesses, pneumonia, urinary tract infection or malaria, but sometimes not at all be linked to an apparent reason. When circumstances such as a fever accompanied by muscle pain, feeling weak, no appetite and may have a runny nose, cough and sore throat, usually classified as influenza or common cold. In practice 90% of patients with fever who had just experienced, is basically a self-limiting diseases such as influenza or other similar viral diseases. But this does not mean we do not have to remain vigilant against a bacterial infection.
Careful physical examination should be repeated regularly. Results axillary temperature measurement is known as an unreliable guide. Special attention should be devoted to the skin, lymph nodes, the nail bed eyes, cardiovascular system, chest, abdomen, muskuloskleletal system and the nervous system. Rectal examination provides a fairly impressive benefits. Penis, prostate, scrotum, and testes should be examined thoroughly and if the patient is circumcised, preputium must retracted.

Investigations are needed in dealing with patients with fever: 

Investigations of major and first thing to do in dealing with patients with fever is:

• Complete blood and urine examination complete
• Inspection and drops a thick blood smear for malaria
• Widal reaction examination and blood culture for Salmonella
• Urine culture
• Chest X-rays to see the state of pulmonary

1. Serological test which includes examining febrile aglutinins, ASO titer for rheuma fever, tests for rheumatoid arthritis, antinuclear antibodies.
2. Examination of blood chemistry that includes the examination of Ca, P, alkalifosfatase, bilirubin, BUN, creatinine, AST, LDH, glucose and T4, elektroforesa proteins and immunoglobulins.
3. Examination of bone marrow biopsy, aspiration of gastric fluid for direct smear and culture for tuberculosis germs.
4. Skin tests include tuberculin test, test histoplasmin, coccidioidin tests and other tests if it is deemed necessary.
5. Radiological examinations including barium enema, IVP, upper food bsaluran photos, photos of bone to determine the possibility of bone infection or bone tumor
6. Examination which includes examination of radioisotope lung scanning to see pulmonary embolism, heart scanning to see abnormal liver and bone scanning to see a bone tumor.
7. Histopathologic examination including a biopsy of the lymph glands, tumors, liver, skin, muscle and arteria temporalis
8. Angiography examination that includes checking to see lymphangiografi malignant lymphoma, coeliac arteriography for liver tumors, kidney and pancreas. Angiocardiografi to see miksoma atrium and pulmonary angiography to see pulmonary embolism.
9. Surgical intervention which includes examining peritoneoskopi, percobaaan or Thoracotomy surgery.

Long fever were patients who suffered from fever> = 38.5 degrees Celsius for more than one week. In the face of patients with fever for more than a week before thinking about a disease that so much, remember first going to a disease that is frequently encountered

1. Typhoid fever
2. Malaria
3. Tuberculosis
4. Urinary tract infection / kidney
5. Subacute Bacteria Endocarditis
6. Disease violence retikuloendotelial system
7. Collagen diseases.

Remember the possibility of febrile habitualis, is the fever that arises in the afternoon, which occurs in women psiychoneurosa accompanied by weakness, but the blood erythrocyte sedimentation rate within normal limits. By the way relieve stress and sedation fever will disappear. Do not forget the possibility of malingering, is the act of simulation, so that his impression was fever, especially when physicians perform the examination.