ALTERATIONS IN BODY TEMPERATUREINTRODUCTIONTemperature is the hotness or coldness. The body temperatures is the difference between the amount of heat produced and the amount of heat lost to the external environment.BODY TEMPERATURE: In humans the traditional normal value for the temperature is 37C. Various parts of the body are at various temperatures. PHYSIOLOGY: the body temperature is the difference between the amount of heat produced by the body processes and the amount of heat loss to the external environment. Heat produced- Heat lost= Body temperature. TYPES Core temperature: - is the temperature of the interior body tissue below the skin and subcutaneous tissue. The sites of measurement of core temperature are rectum, tympanic membrane, esophagus, pulmonary artery, urinary bladder. Shell temperature: - it refers to body temperature at the surface that is of the skin and subcutaneous tissue. The sites of measurement of shell temperature are skin, axillae and oral. Oral: 37C (98.6F) Rectal: 37.5C (99.5F) Tympanic: 37.5C (99.5F) Axillary: 36.5C (97.6F) Heat is continually produced in the body as a by-product of the chemical reactions called metabolismTemperature calculation:C=(f-32)5/9F= (C x 9/5)+ 32REGULATIONThe balance between the heat lost and heat produced or thermoregulation is regulated by physiological and behavioral mechanisms. Neural control Body temperature is controlled by the hypothalamus. The hypothalamus detects minor changes in body temperature and maintains the body temperature within the critical level referred as set points. Neurons in both the preoptic anterior hypothalamus and the posterior hypothalamus receive two kinds of signals; one from peripheral nerves that reflect warmth/cold receptors and the other from the temperature of the blood bathing the region. These two types of signals are integrated by the thermoregulatory centre of hypothalamus to maintain normal body temperature. When these neurons detect the temperature of blood is too warm, signals radiate to the heat loss centre located in the anterior portion of the hypothalamus which is mainly composed of parasympathetic nerves that when stimulated initiate mechanism to decrease body heat. If cold is detected signals are sent to the heat promoting centre in the posterior hypothalamus which operates mainly through sympathetic nervous system which stimulates mechanisms to produce body heat. In a neutral environment, the metabolic rate of humans constantly produces more heat than is necessary to maintain the core body temperature at 37C. Vascular control: the circulatory system functions as a transportation mechanism responsible for carrying heat from body core to the skin surfaces from where it is transferred to the air through radiation, evaporation, conduction and convection. In order to cool the body the superficial blood vessels dilate which leads to increased blood flow to the skin and is controlled by PNS. SNS produces vasoconstriction when body needs to conserve heat. Heat production: heat is produced in body by metabolism, which is the chemical reaction in all body cells. Food is the primary fuel source for metabolism. As metabolism increases heat production increases and as it decreases less heat is produced. Heat production occurs during rest, voluntary and involuntary shivering and no shivering thermo genesis. Rest: basal metabolism accounts for the heat produced by the body at absolute rest. The average basal metabolic rate (BMR) depends on the body surface area. Thyroid hormones also affect the BMR by promoting the breakdown of body glucose and fat they increase the chemical reactions in almost all the cells of the body. Stimulation of SNS by nor epinephrine and epinephrine also increase the metabolic rate of body tissues. These chemical mediators cause blood glucose to fall which stimulates cells to manufacture glucose. The male sex hormone testosterone increases BMR. Men have higher BMR than women. Voluntary movements: such as muscular activity during exercise require additional energy. The metabolic rate can increase up to 2000 times normal during exercise. Heat production can increase up to 50 times normal. Shivering: is an involuntary body response to temperature differences in the body. The skeletal muscle movement during the shivering requires significant energy. Shivering can increase heat production up to 4-5 times greater than normal. The heat that is produced assists in equalizing the body temperature, and the shivering ceases. No shivering thermo genesis: occurs primarily in neonates. Because neonates cannot shiver, a limited amount of vascular brown tissue present at birth is metabolized for heat production. Heat loss: heat loss and heat production occurs simultaneously. The skins structure and exposure to the environment result in constant, normal heat loss through radiation, conduction, convection and evaporation. Radiation (60%): is the transfer of heat from the surface of one object to the surface of another without direct contact between the two. Radiation occurs because heat transfers through electromagnetic waves. Heat radiates from skin to any surrounding cooler object. Radiation increases as the temperature difference between the object increases. Blood flows from the core internal organs carrying heat to skin and surface blood vessels. However if the environment is warmer than the skin, the body absorbs heat through radiation. The nurses increase the heat loss through radiation by removing the clothing or blankets. The clients position enhances radiation heat loss e.g. standing exposes a greater radiating surface area and lying in a fetal position minimizes heat radiation. Covering body with dark, closely woven clothing reduces the amount heat lost from radiation. Conduction (3%): it is the transfer of heat from one object to another with direct contact. When a warm skin touches a cooler object, heat is lost. When the temperature of two objects is same, the conductive heat loss stops. Heat conducts through contact with solids, liquids and gases. Conduction normally accounts for small amount of heat loss. The nurse increases the conductive heat loss when applying an ice pack or bathing a client with cools water. Applying several layers of clothing reduces conductive loss. The body gains heat by conduction when contact is made with materials warmer than skin temperature.

Convection (15%): it is the transfer of heat away by air movement. Heat is first conducted to air molecules directly in contact with skin. Air currents carry away the warm air. As the air current velocity increases, convective heat loss increases.

Evaporation (22%): it is the transfer of heat energy when a liquid is changed to a gas. The body continuously loose heat by evaporation. About 600-900ml a day evaporates from the skin and lungs, resulting in water and heat loss. This is normal loss and considered insensible water loss and does not play a major role in temperature regulation. When the body temperature rises, the anterior hypothalamus signals the sweat glands to release sweat. Sweat evaporates from the skin surface resulting in heat loss. During exercise and emotional and mental stress sweating is one way to lose excessive heat produced by the increased metabolic rate.Skin in temperature regulationThe skins role in temperature regulation includes insulation of the body, vasoconstriction and temperature sensation. The skin, subcutaneous tissue and fat keep heat inside the body. In the human body, the internal organs produce heat and during exercise and increased sympathetic stimulation. The amount of heat produced is greater than the usual core temperature. Blood flows from the internal organs carrying heat to the body surface. The skin is well supplied with the blood vessels esp., the areas of hands, feet and ears. Blood flow through these vascular areas of the skin may vary from minimal flow to as much as 30% of the blood ejected from the heart. Heat transfers from the blood through vessel walls, to the skins surface and is lost to the environment through the heat loss mechanisms. The bodys core temperature remains within the safe limits. The degree of vasoconstriction determines the amount of blood flow and heat loss to the skin, if the vasoconstriction is too high, the hypothalamus inhibits the vasoconstriction. As a result the blood vessels dilate and more blood reaches the skins surface. On a hot humid day the blood vessels in the hands are dilated and easily visible. In contrast if the vasoconstriction becomes too low, the hypothalamus initiates the vasoconstriction and blood flow to the skin lessens. Thus body heat is conserved.The skin is well supplied with heat and cold receptors. As the cold receptors. Are plentiful the skin functions primarily to detect cold surface Temperatures. When the skin becomes chilled, its sensors send information. To the hypothalamus, this initiates shivering to increase body heat. Production, inhibition of sweating, and vasoconstriction.Behavioral control Humans voluntarily act to maintain comfortable body temperature when exposed to temperature extremes. The ability of person to control body temperature depends no: degree of temperature extreme, the persons ability to sense feeling comfortable or uncomfortable, thought processes or emotions. And the persons mobility or ability to remove or add clothes.Infants can sense uncomfortable warm conditions but need assistance in changing the environment. Older adults may need the help in detecting cold environments and minimizing heat loss. Mechanisms Activated By Cold: Increased heat production: increase in BMR, muscle activity, thyroxin output, epinephrine, nor epinephrine and sympathetic stimulation, fever. Decreased heat loss by coetaneous vasoconstriction, curling up.Mechanisms Activated By Heat: Increased heat loss by cutaneous vasodilatation, sweating, increased respiration Decreased heat production: manifested by anorexia, apathy, illness.FACTORS AFFECTING THE BODY TEMPERATUREMany factors affect the body temperature. Changes in body temperature within an acceptable within an acceptable range occur when the relationship between the heat production and the heat loss is altered by physiological or behavioral variables.1. Age: at birth the newborn leaves a warm, relatively constant environment and enters one in one in which temperature fluctuates widely. Temperature control mechanisms are immature. An infants temperature may respond drastically to changes in the environment. Extra care is needed to protect the newborn from environmental temperatures. Clothing must be adequate and exposure to the temperature extremes must be avoided. A newborn loses up to 30% of body heat through the head and therefore needs to wear a cap to prevent heat loss. The newborns body temperature is maintained within 35.5-37.5C (95.9-99.5F). Heat production steadily declines as the infant grows into childhood. Childrens temperatures continue to be more variable than those of adults until puberty.Older adults are particularly sensitive to temperature extremes because of deterioration in control mechanisms particularly poor vasomotor control (control of vasoconstriction and vasodilatation), reduced amounts of subcutaneous tissue, reduced sweat gland activity and reduced metabolism, reduced intake of diet.2. Exercise: muscle activity requires an increased blood supply and an increased fat and carbohydrate breakdown that causes increases in heat production. Any form of exercise increase the heat production and thus the body temperature. Prolonged strenuous exercise, such as long distance running, can temporarily raise body temperatures up to 41C (105.8F).3. Hormone level: women generally experience greater fluctuations in body temperature than men. Hormonal variations during the menstrual cycle cause body temperature fluctuations. Progesterone levels rise and fall cyclically during the menstrual cycle. When progesterone levels are low, the body temperature is a few tenths of a degree below the baseline level. The lower temperature persists until ovulation occurs. During ovulation, greater amounts of progesterone enter the circulatory system and raise the body temperature to previous baseline levels or higher by 0.3-0.6(0.5-1.0F). Body temperature changes also occur in women during menopause (cessation of menstruation). Women who have stopped menstruating may experience periods of intense body heat and sweating lasting from 30 second to 5 minutes. There may be intermittent increases in skin temperature of up to 4C (7.2F) during these periods, referred to hot flashes. This is due to the instability of the vasomotor controls for vasodilatation and vasoconstriction.4. Circadian rhythm: body temperature normally changes 0.5-1C (0.9-1.8F) during a 24 hour period. The temperature is usually lowest between 1.00- 4.00 am. During the daytime the body temperature rises steadily up to 6.00pm and then declines to early morning levels.5. Stress: physical and emotional stress increase body temperature through stimulation of sympathetic nervous system due to increase in production of epinephrine and nor epinephrine thereby increasing metabolic activity and heat production. A client who is anxious could have an elevated body temperature for that reason.6. Environment: extremes of environment can affect a persons temperature regulatory systems. If temperature is assessed in a warm room, a client may be unable to regulate body temperature by heat loss mechanisms and the body temperature will be elevated. Similarly, if the client has been outside in extremely cold weather without suitable clothing the body temperature may be low.FEVER Fever is an elevation of body temperature that exceeds normally daily variation and occurs in conjunction with an increase in the hypothalamic set point for e.g. 37C-39C. CAUSES OF FEVER Hot environment. Excessive exercise. Neurogenic factors like injury to hypothalamus. Dehydration after excessive dieresis. As an undesired side effect of a therapeutic drug. Chemical substances e.g. caffeine and cocaine directly injected into the bloodstream. Injection of proteins or other products. Infectious disease and inflammation. Severe hemorrhage.SYMPTOMS OF FEVER Flushed face; hot dry skin; anorexia; headache; nausea and sometimes vomiting; constipation and sometimes diarrhea; body aches and scant highly colored urine. Clinical signs of fever: Increased heart rate, respiratory rate and depth; shivering; pale cold skin; cyanotic nail beds; cessation of sweating CLASSIFICATION OR PATTERNS OF FEVER1. Intermittent fever: the temperature curve returns to normal during the day and reaches its peak in the evening. E.g.: in septicemia2. Remittent fever: the temperature fluctuates but does not return to normal. E .g: TB, viral diseases, bacterial infections3. Sustained fever: the temperature remains elevated with little fluctuation.4. Relapsing fever: periods of fever are interspersed with periods of normal temperature. Tertian- when paroxysm occurs on 1st and 3rd days Quatrain- fever associated with paroxysm on first and fourth day. E.g. in malariaPATHOGENESIS OF FEVER:1. Pyroxenes: progeny is any substance that causes fever. Exogenous pyroxenes are derived from outside the patient; most are microbial products, toxins or micro-organisms. E.g.: lip polysaccharide end toxin produced by all gram negative bacteria. Enter toxins of gram positive like staphylococcus aurous and Group. A and B Streptococcal toxins2. Phylogenic cytokines: cytokines are small proteins that regulate immune, inflammatory and hematopoietic processes. For e.g. stimulation of lymphocyte proliferation during any immune response to vaccination is the result of the cytokines interleukin (IL) 2, IL-4, IL-6, TNF (Tumor Necrosis Factor). Some cytokines cause fever and are called phylogenic cytokines including IL-1, IL-6, and interferon (IFN) alpha. Each cytokine is encoded by a separate gene and each phylogenic cytokine has been shown to cause fever. 3. Elevation of hypothalamic set point by cytokines: during fever, levels of prostaglandin E2 (PGE2) are elevated in hypothalamic tissue. Cytokines pass from circulation to brain. The endogenous and exogenous pyroxenes interact with the endothelium of hypothalamus and raise set point of febrile cells.4. Production of cytokines in CNS: several viral diseases produce active infection in the brain. Glial or neuronal cells synthesize IL-1, IL-6, and TNF. Therefore CNS production of cytokines raises hypothalamic set point.GRADES OF FEVER1. low grade fever: 37.1-38.2C(98.8-100.6F)2. high grade fever: 38.2-40.5C(100.6-104.9F)3. hyperpyrexia: >40.5C(104.9F)PHASES OF FEVER A febrile episode has three distinct phases:-1. Chill phase: the bodys heat producing, mechanism attempt to increase the core temperature. The client experiences cold and may shiver. Goose flesh caused by contraction of erector Pilli muscles in an attempt to trap air around body hairs, is evident. Skin becomes pale and cool due to vasoconstriction.2. Fever phase: it occurs when fever reaches the new higher set point. The clients skin feels neither hat nor cold. Cellular degeneration leads to fluid and electrolyte losses. If fluid volume deficit has occurred the client may experience thirst. Complains of aching muscles, general malaise weakness can be there due to increased of protein catabolism. Client may be drowsy or restless. An uncontrolled fever can make the patient delirious and to suffer from convulsions due to cerebral nerve cell irritation.3. Flush or crisis phase: during this phase the client experiences profuse diaphoresis, decreased shivering and possible fluid volume deficit. The clients skin appears flushed and warm to touch because of vasodilatation.HYPERTHERMIA Hyperthermia is characterized by an unchanged (normothermic) setting of the thermoregulatory center in conjunction with an uncontrolled increase in body temperature that exceeds the bodys ability to lose heat. Exogenous hest exposure and endogenous heat production are two mechanisms by which hyperthermia can result in dangerously high internal temperatures. Excessive heat production can easily cause hyperthermia despite physiologic and behavioral control of body temperature. For e.g.: work and exercise in a hot environment can produce heat faster than peripheral mechanisms can lose it. Although most patients with elevated body temperature have fever, there are few circumstances in which elevated body temperature represents not fever but hyperthermia.

CAUSES OF HYPERTHERMIA SYNDROMES1. Heat stroke: caused by thermoregulatory failure in association with an arm environment may be categorized as exceptional and non exceptional. Exceptional: it occurs in younger individuals who exercise in higher than normal heat or humidity, dehydration Non exceptional: it is caused by anti cholinergic, including antihistamines, anti parkinsonian drugs, diuretics, phenothiazines. It occurs in either in very young or elderly during heat waves, bedridden patients, elderly and taking drugs confined to poorly ventilated and non AC environment.2. Drug induced hyperthermia: due to increased use of psychotropic drugs. Monoamine oxidizes inhibitors, tricycle antidepressants, amphetamines, phencyclidine, lysergic acid diethylamide or cocaine.3. malignant: occur in individuals with inherited abnormality of skeletal muscle sarcoplasmic reticulum that cause rapid increase in intracellular Ca level in response to halothane and other inhalation anesthetics or to succinylcholine. In this there is elevated body temperature, increased muscle metabolism, muscle rigidity, rhabdomyolysis, acidosis and cardiovascular instability and is often fatal.4. The narcoleptic malignant syndrome (NMS): occur due to use of narcoleptic agents like antipsychotic phenothiazines, haloperidol, pro chlorprazine, meto chlopramide or withdrawal of dopaminergic drugs and is characterized by muscle rigidity (lead pipe), extra pyramidal side effects, autonomic deregulation and hyperthermia. It is caused by inhibition of central dopamine receptors in hypothalamus which results in increased heat generation and decreased heat dissipation5. serotonin syndrome: seen in selective serotonin uptake inhibitors(SSRIs), MAOs and serotonergic medications have overlapping features including hyperthermia but distinguished by presence of diarrhea, tremors, myoclonous rather than lead pipe rigidity.

6. endocrinopathy: thyrotoxicosis and pheochromocytoma can lead to increased thermogenesis7. central nervous system damage: cerebral hemorrhage, status epileptics, hypothalamic injury can cause hyperthermiaAPPROACH TO THE PATIENT1. History: history of use of OTC medications, or treatment such as surgical/dental procedures. Nature of prosthetic materials or dental procedures. Occupational history, exposure to animals, infectious agents, febrile or infected individuals in the home, workplace/O geographic areas patient traveled. Use of tobacco, IV drugs, trauma, animal bites, immunization. Family history of TB, arthritis, infectious disease, anemia. Ethnic origin e.g. blacks are more likely to have haemoglobinopathies2. Physical examination: vital signs, check skin, lymph nodes, eyes, nail beds, CVS, chest abdomen, musculoskeletal system, nervous system, penis, scrotum, testes should be examined carefully. Pelvic examination for PID and tubo-ovarian abscess.3. laboratory tests: if a patient reveals more than a simple viral illness or pharangitis then lab testing is done:

CLINICAL PATHOLOGYCBC, DLC. Neutrogena is present in some viral infections, drug reactions, SLE, typhoid, leukemia. Lymphocytosis will be presenting with typhoid, brucellosis, TB and viral diseases. Monocytosis in typhoid, TB, brucellosis, lymphoma. Eosinophilia in hypersensitivity and drug reactions, Hodgkins disease, adrenal insufficiency. Blood smear for malarial pathogens, ESR. Urinalysis. Any abnormal fluid accumulation like pleural fluid, peritoneum, joint is examined. Bone marrow biopsy for histopathologic studies as well as culture in infiltration of marrow by pathogens or tumor cells. Stool for occult blood, inspection for ova, parasites. Chemistry: electrolytes, blood glucose, BUN, creatinine, LFT Microbiology: smears and cultures of specimen from throat, urethra, anus, cervix, vagina. When there are no localized findings or when findings suggest the involvement of pelvis, GIT. If respiratory infection than sputum evaluation (Gram staining, staining for AFB, culture). Cultures of blood, abnormal fluid collection, urine if fever reflects more than uncomplicated viral illnesses. CSF examined and cultured if meningismus, severe headache or change in MSE is there. Radiology: a chest X-ray is part of evaluation for any significant febrile illness.

MEDICAL MANAGEMENT It is important to distinguish between fever and hyperthermia since hyperthermia can be rapidly fatal and doesnt respond to antipyretics. Pharmacological management1. Acetaminophen: adult: 325-650 mg PO q 4-6 hrs. Children: 10-15mg/kg body weight q4-6 hrs.2. Ibuprofen (NSAID) - dosage: adult-200-400mg PO q6hrs; children: 5mg/kg body wt for temp. 38.5C, irritability, increased respiratory rate and dry skin: Remove excess clothing and covers, cover with light warm clothing to avoid chilling, monitor temperature as needed, encourage cool fluids, apply lubricant to dry lips and nasal mucosa, increase air circulation to encourage cooling, control environmental temperature not too cold, administer antipyretics as prescribed, cool with tepid bath, adjust cooling measures on the basis of temperature, notify physician of significant change. Altered comfort as evidenced by restlessness: Promote rest, restrict activity, assess clients response to pain management, and take safety precautions if patient is delirious, monitor for decreasing level of consciousness. Altered nutrition related to fever as evidenced by anorexia and lack of food intake: Provide high calorie diet, encourage fluid intake, reduce iron intake During flush phase: Altered fluid and electrolyte balance related to excessive sweating: Monitor intake and output, monitor electrolytes, replace fluids and electrolytes lost through sweating, monitor temperature, and provide rest. HEAT CRAMPS These painful muscle cramps occur most commonly in the legs of young people following vigorous exercise in the hat weather. There is no elevation of core temperature. The mechanism is considered to be extracellular sodium depletion following electrolyte loss a result of persistent sweating with replacement of water but no salt. The syndrome is also encountered in miners undertaking heavy physical work in hat conditions with very limited ventilation, which impairs the effect of evaporative heat loss from sweating. Symptoms usually respond to salt replacement.

HEAT EXHAUSTIONHeat exhaustion occurs when there is an elevation in core (rectal) temperature to between 37-40C and is usually seen when the individual is undertaking vigorous physical work in a hat environment. A high work rate, extreme ambient temperature, impairing

evaporative heat loss due to high humidity or inappropriate clothing may all combine to overcome thermoregulatory control. The diagnosis is based no the findings of an elevated core temperature associated with hyperventilation and symptoms of tiredness or fatigue, muscular weakness, dizziness and collapse. The blood analysis may show evidence of dehydration with mild elevation of blood urea, sodium concentration and hematocrit. Treatment involves removal of patient from the heat, active cooling using cool sponging, and fluid replacement. This may be achieved by oral dehydration mixtures containing both salt and water or intravenous isotonic saline . Adult patients may require 5 liters or more positive fluid balance in the first 24 hours. Frequent monitoring of blood electrolytes is important, esp. in patients receiving I.V. replacement therapy.HEAT STROKE Heat stroke occur when the core body temperature rises above 40C and is a severe and life threatening condition provoked by failure of heat regulatory mechanisms. The symptoms of heat exhaustion progress to include headache, nausea and vomiting. Neurological manifestations include a coarse muscle tremor and confusion, which may progress to loss of consciousness. The patients skin feels very hot, and sweating is often absent due to failure of thermoregulatory mechanisms. The condition may progress from heat exhaustion or present acutely in a patient who has become progressively dehydrated without symptoms. Coincidental illness age and drug therapy, particularly phenothiazines diuretics and alcohol may be the contributory factors. Complications include Hypovolemic shock, lactic acidosis, and disseminated intravascular coagulation. Rhabdomyolisis, hepatic and renal failure and cerebral edema. The patient should be managed in ICU with rapid cooling using ice packs, careful fluid replacement and appropriate intravascular monitoring. Investigations reflect the complication sand include coagulation studies and muscle enzymes and in addition to routine hematology and biochemistry

FEVER OF UNKNOWN ORIGIN

DEFINITION:Fever of unknown origin (FUO) was defined by Peterson and Benson in 1961 as (1) temperatures of > 38.3 degree Celsius (>101 degree Fahrenheit) in several occasions; (2) a duration of fever of > 3 weeks and; (3) failure to reach a diagnosis despite 1 week of inpatient investigation.CLASSIFICATION OF FUO:Derrick and Street have purposed a new system for classification of FUO:-1. Classic FUO: same as above criteria. E.g. infections, malignancy, inflammatory diseases, drug fever.2. Nosocomial FUO: a temperature of >= 38.3 C (>=101 F) develops on several occasions in a hospitalized patient who is receiving acute care and in whom infection was not present at time of admission. For e.g. septic thrombophlebitis, sinusitis, drug fever.3. Neutropenic FUO: a temperature of >= 38.3 C (>=101 F) develops on several occasions in a patient whose neutrophil count is < 500/micro liter or is expected to fall to that level in 1-2 days.4. HIV- associated FUO: a temperature of >= 38.3 C (>=101 F) develops on several occasions over a period of > 4 weeks for outpatients or > 3 days for hospitalized patients with HIV infection.CAUSES OF FUO:1. Infections: Localized phylogenic infections: appendicitis, cholecystitis, dental abscess. Intravascular infections: bacterial endocarditic. Systemic bacterial infections: typhoid fever. Mycobacterium infections: tuberculosis. Fungal infections: candidacies. Viral infections: dengue, hepatitis A, B, C, D and E, HIV infection. Parasitic infections: amebiasis, malaria. Rikettsial infections. Mycoplasmal infections. Chlamydial infections.2. Neoplasms: (a) malignant: colon cancer, gall bladder carcinoma, leukemia, renal cell carcinoma.(b) benign: castle mans disease3. Habitual hyperthermia: exaggerated circadian rhythm4. Collagen vascular/ Hypersensitivity diseases: rheumatic fever, rheumatic arthritis, systemic lupus erythematous5. Granulomatous Diseases: crohns disease6. Miscellaneous conditions: drug fever, gout, haemo globinopathies, tissue infarction or necrosis7. Inherited and metabolic diseases: adrenal insufficiency, familial cold urticaria8. Thermoregulatory Disorders: (a) Central: brain tumor, Cerebro vascular accident, encephalitis; (b) Peripheral: hyperthyroidism, pheochromocytomaDIAGNOSIS OF FUO:History and physical examination, blood investigations, tumor markers, PPD for TB, serological studies, peripheral smears, multiple samples for culture and sensitivity, X-Ray studies, bone marrow biopsy, Liver biopsy, GI contrast studies, CT scan, MRI, ultrasonography.TREATMENTThe patients with classic FUO are continually observed and examined and not given the empirical therapy. The antibiotic therapy given to the patient can delineate the ultimate cause of FUO. If neutropenia and vital sign instability are present then empirical therapy with fluroquinolone and piperacillin is given. If PPD test is positive or granuloma hepatitis is confirmed then isoniazid and rifampcin for 6 weeks is given. When no underlying source of infection is found even after 6 months the prognosis is generally good. The debilitating symptoms are treated by NSAIDSs and glucocorticoids.

HYPOTHERMIAHypothermia is a state in which the core body temperature is lower than 35 degree Celsius and 95 degree Fahrenheit. At this temperature many of the compensatory mechanism to conserve heat begin to fall.CLASSIFICATION1. Primary hypothermia: it is a result of the direct exposure of a previously healthy individual to the cold.2. Secondary hypothermia: it is hypothermia that results due to a complication of a serious systemic disorder.

3. Accidental hypothermia: it results from unintentional exposure to cold or wet and windy climate with an ambient temperature less than 16 degree Celsius.4. Induced hypothermia: it is deliberate lowering of temperature to a range of a 78-90F (26-32.5C) to reduce oxygen need during surgery (esp. cardiovascular and neurosurgical procedures) and in hypoxia, to reduce blood pressure and to alleviate hyperthermia by administering drugs that depress the hypothalamic thermostat or by encasting the client in a cooling blanket.CAUSES1. Exposure to cold environment in winter months and colder climates.2. Occupational exposure or hobbies that entail extensive exposure to cold for e.g. hunters, skiers, sailors and climbers.3. Medications like ethanol, phenothiazines, barbiturates, benzodiazepines, cyclic antidepressants, anesthetics.4. Endocrine dysfunction: hypothyroidism, adrenal insufficiency , hypoglycemia5. Neurologic injury from trauma, Cerebral vascular accident, Subarachnoid hemorrhage6. SepsisRISK FACTORS FOR HYPOTHERMIA:1) Age extremes: elderly, neonates.2) Outdoor exposure: occupational, sports-related, inadequate clothing.3) Drugs and intoxicants: ethanol, phenothiazines, barbiturates, anesthetics, neuromuscular blockers and others.4) Endocrine related: hypoglycemia, hypothyroidism, adrenal insufficiency, and hypopituitarism.5) Neurologic related: stroke, hypothalamic disorders, Parkinsons disease, spinal cord injury.6) Multisystem: malnutrition, sepsis, shock, hepatic or renal failure.7) Burns and exfoliative dermatologic disorders.8) Immobility or debilitation.CLINICAL PRESENTATION:Hypothermia leads to physiological changes in all organ systems.Mild35-32.2C (95-90F) Decreased cerebral Metabolism Amnesia Apathy Dysarthria Impaired judgement Tachycardia Vasoconstriction Increase in cardiac output and Blood pressure Tachypne, Bradypnea Decline Oxygen consumption Bronchospasm Diuresis Increase in metabolism with shivering Increased preshivering Muscle tone Fatiguing AtaxiaModerate