THE PROLONGED FEVER
The fever is a common symptom in children. While most of the adult
individuals go to see a doctor when feeling pain, in children the most frequent
symptom that determines a medical examination is the raise of the body
temperature.
The humans are homeotermic (warm blood) beings who are able to
maintain a constant body temperature of approximately 37 Celsius degrees by
means of balance between the production and the loss of the metabolic heat.
In homeotermic animals the central body temperature, also called as inner
temperature, is kept constant, while the peripheral body temperature (skin and
muscle at the limbs extremities ) varies along with the environment temperature
and the changes of the skin circulation and secretion that fight against any
variation of the body temperature.
To measure the body temperature means, in fact, to determine the inner
temperature.
The most representative values are:
1.the rectum temperature ; 37, 3 – 37,5 Celsius degrees ( C d)
2.the mouth temperature : 37 C d.
3.the axilla temperature : 36,5 C d.
The body temperature varies during the day-time from 36,4 C d. at 4 to 6
a.m. to 37,4 C.d. at 6 p.m. In women the body temperature also changes during
the ovarian cycle with a periodicity rate of about 28 days. The ovulation that
occurs in the middle of the interval between two menstruations, determines a
raise of 0,5 to 1 C.d. in the body temperature values that remain elevated until
the beginning of the next menstruation because of the high progesterone levels.
The constant body temperature is the result of the balance between the
production and the loss of the heat: thermogenesis and thermolysis. During rest
the main place for thermogenesis situates in the thoraco-abdominal organs
(70%), the rest of 30% of heat being produced inside the brain, muscles and
skin. During physical activity the muscles are able to increase their heat
production up to 20 times.
The comfort temperature of the environment that determines minimal
thermogenesis levels lays between 20 and 22 C.d. when dressed and 26 to 30 C
d. when undressed.
The response to coldness is the peripheral vessels constriction that reduces the
loss of heat and the increase of heat production.
The body heat is lost by means of:
1.Radiation: up tp 60% of the body heat is lost in this way, being absorbed by
the solid and fluid matters that touch the body surface. That’s why undressing
the child is recommended during high fever.
-22.Conduction : the absorption of about 3% of the body heat by solid objects,
such as chairs and beds. The clothes provide a relative isolation that opposes to
this loss.
3.Convection : the absorption of the body heat by the fluid environmental matter
(air, water when swimming ). The heating may determine air circulation that
promotes the contact of the body surface with layers of cold air.
4.Evaporation of the insensible perspiration = water evaporation from the moist
surfaces of the body, such as respiratory tract and skin, that is not due to the
activity of the sweat glands (about 500 ml daily). Sweat occurs during body
movements or excessive heating.
The physiological mechanisms that contribute to the loss of heat are:
-The raise of the skin circulation flow that leads to a more active radiation and
conduction when the difference between the body and environment temperatures
is big enough.
-The increased secretion of sweat occurs whenever the body temperature
raises beyond 34,5 C d. and determines high evaporation that leads to heat
losses. This mechanism is effective only when the surrounding air is dry enough.
The moist may lead to overheating of the body.
The thermoregulation is controlled by several hypothalamic centers:
The fever occurs whenever the thermoregulation centers switch on to
higher temperature values. Nevertheless, the heat exchanging mechanisms adapt
to this higher levels.
Metabolic changer during fever: hyperglicemy, high rate of the protein
catabolism, high rate of the basic metabolism, cardiac and respiratory
acceleration.
The piretogenic substances ( bacterial toxins, foreign proteins, self
proteins from cell death ) do not act directly on the thermoregulations centers,
but trigger the granulocytes response which seizes these substances and release
the endogenic leucocyte pirogene. a protein of the leukocyte membrane that acts
directly on the hypothalamic thermoregulation centers and determines fever.
The fever starts with a reduction of the loss of heat by means of skin
vessels contraction and chills that give a sensation of coldness. In the meantime
the body temperature reaches new homeothermic value ordered by the
hypothalamic centers.
During infections the fever increases the rate of the cell metabolism, thus
creating the best conditions for an effective immune response and fagocitosis.
This explains the use of the fever on therapy purpose.
-3DIAGNOSIS
In case of acute fever the diagnosis is suggested by the clinical
and laboratory findings. Sometimes the prolonged fever is the unique symptom
of a disease. Such fever may look either like a permanent low fever or high
fever. In some cases there is a prolonged low fever interrupted by short periods
of high fever.
Any fever that lasts for more than 6-8 days long without revealing its cause
becomes an important diagnosis problem because it may be the unique sign of a
severe disease.
The examination must begin with a serious and detailed inquiry and continue
with a complete clinical check-up.
Are to be examined: the skin, the mucous of mouth and pharinx, the facial
sinuses, the lymph nodes, the muscles and joints, the uro-genital system and the
anal region.
The laboratory determinations will be conduced according to the inquiry
and clinical findings.
The distinction between infectious and noninfectious fever is to be made, by
means of:
- blood cell counting
- erythrocytes sedimentation rate (Ε S R)
- urine examination
- genital examination
- chest radiographic exam. and tuberculinic test
- E.N.T. and stomatologycal examination
If still no diagnosis has been established further examinations will follow :
blood, urine and faeces cultures, cerebrospinal fluid (CFS) cultures, bone
marrow biopsy, lymph nodes biopsy, urographic examination, immune
capability determinations, blood serology and sometimes even laparoscopic
examination.
In some cases the diagnosis is cleared after death.
In some cases the response to therapy proves a diagnostic, but such an
eventuality is better to be avoided because nowadays excessive use of
antibiotics and corticoid drugs is able to modify the fever and the other
symptoms and cover the true diagnosis for a long time.
The first step to be made is the repeated measurement of the fever, in order to
find out if the patient is telling the truth or is lying. When the fever is well
tolerated no therapy will be recommended in order to observe the character of
the fever :
1.Constant low fever which does not go over 37,4 C.d. with very small
variations of 1 to 2 decimals degrees, not influenced by antithermic drugs.
-4The cause is usually endocrines increased estrogene levels, hyperthiroidism and
postinfectious state.
2.Constant low fever with variations of 4-5 decimals degrees which associates
mild anemia, increased leukocyte level, high ESR is caused by focal bacterial
infections and onset of tuberculosis.
3.Continuous remittent high fever : varies from 37.5 C.d.. to over 40 C.d. and is
caused by tuberculosis, brucellosis, leukemia and lymphomas.
4.Remittent low fever: does not go over 38 C.d. and is caused by
bronchiectasias or subacute bacterial endocarditis.
5.Intermittent "gothic" fever : continuous low fever with intermittent high raises
of temperature la case of : angiocolitis, pielitis, ulcerative colitis, bacterial
endocarditis, infected cancers. In malaria this type of fever occurs regularity
every 2 or 3 days.
6.Chronic recurrent fever : increases and decreases slowly and periodically.
Occurs in brucellosis, Hodgkin disease.
7.The acute septic fever : permanent high fever with oscillations between 37 and
40 C.d. that associates chills.
8.The hectic fever : irregular oscillations between 37 and 38 C.d.
Occurs in case of extra pulmonary tuberculosis.
THE HYPERTHERMY : is the result of a passive heating of the body that
overdrives the thermolysis capacity and leads to excessive raise of the inner
temperature.
Occurs during extremely intense muscular effort, exposure to dry and hot
air or excessive moist. Up to 39 C.d. the hyperthermy is well tolerated. Over 40
C.d. develops the thermic shock that is the result of the circulatory failure due to
the excessive dilatation of the peripheral blood vessels and migration of the
blood towards the periphery. The main signs are: low blood pressure, decreased
cardiac flow, loss of conscience.
The excessive production of sweat lowers the salt blood levels and thus
may lead to muscle contractions that need intravenous administration of NaCl.
The maximal temperature that can be tolerated by a human layes between
43 and 43.5 C.d.
TYPES OP TEMPERATURE RAISES
A. Hyperthermy : has nothing in common with fever. Occurs in case of:
a) termic shock (excessive exposure to sun, working accidents, unbalanced
incubator);
b) the fever caused by screaming and crying in suckling and small children;
c) the thirst fever of the small children when fed with few water and high
density powder milk;
d) the dehydration fever in case of diabetes insipidus;
-5e) pathological thermolysis in case of wide burn, ichtiozis and congenital
absence of sweat glands.
The malignant hyperthemy; occurs in hereditary predisposed individuals and
consist of extremely high fever strokes ( 40-42 C.d.) during the administration of
anesthetic and muscle relaxing drugs previous to surgery. The first symptom
may be the muscular contraction followed by hot skin, tachicardia, aritmias, low
blood pressure and marble-looking cyanose. This is an emergency situation that
needs immediate stop of the drug administration, antithermic drugs and shock
therapy.
The habitual hyperthermy : healthy individuals whose termoregulation
balance is switched to a higher level ( 37,5-38 C.d.) than what is to be normal.
This temperature provides with no discomfort these individuals and antithermic
drugs show no efficiency.
Β. Nοn infectious fever
1) Neurologic fever : malfunction of the hypothalamic centers in case of :
-cerebro-meningeal haemorrhage at birth
-internal hydrocephalus
-subdural haematoma
-diencephale tumours
-fever after brain surgery
-chronic encephalopathy ( the general state of health remains good enough, lasts
for more than 3 month, over 39 C.d. fever, no leukocytosis and no infection
findings, the antithermic drugs give no benefit ).
-chranial traumatisms
2) The endocrine fever : Basedow disease, high estrogenes levels.
3)The fever that accompanies the absorption of the injured tissues after
contusions, infarctisations, drug-caused aseptic necroses, surgery, the absorption
of haematomas and internal haemorrhages, paroxistic haemoglobinuria.
4) Low fever that acompanies the astenic neuroses.
5)The drug-induced fever : develops after the intake of sulphamides, salicilates,
hidrazide, phenobarbitale , hidantoin and antibiotics. The most common findings
are: joints pain, cyanose, dermatitis, leukopenia, all these resulting in the typical
"9th day syndrome". Sometimes
the symptoms develop next to the
administration. The interruption of the drug administration gives a sudden relief.
In some cases of infections treated with antibiotics a prolonged fever may stop
within 24-48 hours after the interruption of any drug, proving that the fever was
drug-induced.
6) Prolonged low fever in iron defficient suckling that comes back to normal
soon after the beginning of the iron administration.
-6C.THE INFECTIOUS FEVER : is quite frequent, but sometimes atypical and
oligosymptomatic forms of several diseases are to be thought about :
1) Typhoid fever is a difficult diagnosis when the onset is not typical, when
antibiotics have already been tried and when the patient is vaccinated (abortive
forms). Key findings: splenomegaly and low leukocyte counting. High positivity
rate in blood and faeces cultures during the first week and lower rate afterwards.
Blood serology through the Widal reaction is still of great importance.
2) Septicaemic salmonellosis : is an evolution pattern found in sucklings and
small children with immune deficiencies. Symptoms : irregular continuous or
intermittent fever, chills, alterations of the general state of health, splenomegaly.
The salmonella septicaemia is not followed by immunization. The faeces culture
are often negative while the blood cultures are positive.
3) Septicaemias caused by : Staphylococcus. Streptococcus, E,Goli, Klebsiella,
Pseudomonas are diagnosed through repeated blood cultures before any
antibiotic has been given or after a sufficiently long period when no antibiotic
has been given.
4) Brucelosis : associates fever in contrast with the good general state of health,
muscular pain, neuralgias, joints pain, bed smelling night sweating,
splenomegaly and lymph nodes hypertrophy, low blood leukocyte counting
because of low neutrophile levels.
Blood serology: Wright’s reaction. The professional background may be
suggestive (veterinary doctors, cow working people).
5).Tuberculosis:
primary infection: low fever, sweating, suggestive chest X ray
examination, positive reaction to tuberculine;
miliary tuberculosis: (disseminated tuberculosis): high irregular fever,
chills, dispnoea, cyanose, cough, lymph nodes hypertrophy, splenomegaly,
pleuresia, pericarditis, meningitis, high ESR, high neutrophile levels with
decreased total leukocyte counting, suggestive chest X ray examination, positive
cultures for BK and positive tuberculin test.
6) Infectious mononucleosis: associates fever, hypertrophic lymph nodes,
pseudomembranous angina, hepatosplenomegaly, high leukocyte counting
(lymphomonocitosis), positive Paul-Bunnell reaction, positive determination of
IgM type antibodies against the Epstein Barr virus (indirect
immunofluorescence).
7) Typhus: permanent 39-40 C.d. fever that lasts for about 2 weeks, maculopeteshial skin rash, circulatory troubles ( increased heart rate and low blood
pressure ), neurological disorders (headache, state of confusion, delirium,
adinamy, dizartry, balance trouble ), cerebrospinal fluid (CSF) abnormal
findings, high leukocyte counting because of an increased number number of
-7neutrophiles. Diagnosis is established by positive Weil-Felix and complement
binding reaction.
8) Leptospirosis: fever, headache, muscles pain, conjunctivitis, meningeal signs,
kidney and liver affectation, leukocytosis with high neutrophile rate, very high
ESR. Blood and urine cultures and agglutination-killing reaction are positive.
The disease is transmitted by rat urine in water.
9) Malaria characteristic stroke (chills, fever, sweating) which occur in a regular
way every 42-72 hrs, anemia, splenomegaly.
Microscopic examination of blood erythrocytes is diagnostic.
10) Anicteric forms of viral hepatitis.
11) Aquired toxoplasmosis : hypertrophiy lymph nodes. The indirect
immunofluorescence is diagnostic . IgM type antibodies are present in case of
recent infection.
12) Systemic fungal infection : chronic septic state that occurs during prolonged
antibiotic or corticosteroid therapy. Several positive blood cultures with the
same fungus and tissue examinations are diagnostic.
13).Triquinosis- gastro-intestinal onset : abdominal pain, vomiting and diarrhoea
associated with high fever. After one week muscle pains, eyelids edema,
miocardial and nervous affectations. Diagnostic bases on epidemiologic inquiry
(several cases of high unexplained fever in related individuals), very high blood
eosinophil levels, presence of triquinella in the muscle biopsy taken from a
painful area.
14) Acute ENT infections (ears, nose, throat) :
-Stomatitis
-Chronic adenoiditis
-Otoantritis and mastoiditis : fever, ear secretion, vomiting, aspect of the
mastoid region.
-Sinusitis :fever, headache, sinusal pains, high neutrophile levels, suggestive
findings at the X ray exam, of the sinuses.
15) Respiratory tract infections.
-Bacterial bronchopneumonia ( Staphilococcus and Gram negative bacteria):
fever, cough, dispnoea, suggestive chest X ray examination, high blood
leukocyte levels.
16) Bacterial UTI : fever, anorexia, vomiting, diarrhoea, frequent urination and
urgency, bed smelling urine, restlessness. Urine cultures and urographic exam.
may clear the diagnosis.
17) Liver and biliary tract infections : prolonged fever, jaundice, right
hipochondrium pain, high neutrophile levels. Diagnosis bases on the cultures,
radiographic exam. of the biliary tract, ultrasonography.
18) CNS infections: cerebral abscesses, encephalitis, bacterial meningitis.( fever,
headache, csf exam, neurologic troubles).
-819) Profound tissues infections
20) Osteomielitis :late radiology finding.
21) Acute miocarditis : prolonged low fever, tiredness, palpitations, chest pain,
ECG findings.
D. AUTOIMMUHE DISEASES, COLAGENOSIS
1) Acute Rheumatic Fever : fever, arthritis, high BSR, high ASLO blood levels,
increased leukocyte counting.
2) Juvenile chronic arthritis ( Still disease ): septic type fever, inconstant
macular skin eruption, poliartritis, adenonepatosplenomegaly, pericarditis,
iridociclitis, anemia, high leucocyte levels, high ESR, etc.
3) Lupus : fever, alteration of the general state of health, anorexia, migratory
arthritis, hypertrophic lymph nodes, cardiomegaly, endocarditis, lupic hepatitis,
kidney affectation, low albumine levels, high ESR, anti-nuclear antibodies, LE
cells, low complement level, positive Waller-Rose and BW reactions.
4) Polyarteritis nodosa.
5.) Dermatomyositis
6) Hashimoto's thyroiditis.
E. MALIGNAT DISEASES.
1) Hodgkin's disease: fever, lymph nodes hypertrophy, night sweating, itching.
high leukocyte levels and eosinophilia, high ESR, suggestive lymph node
biopsy.
2) Non Hodgkin malignant lymphoma : fever, polimorphic manifestations,
lymph nodes hypertrophy, hepatosplenomegaly, loss of weight, suggestive
lymph nodes biopsy.
3) Acute leukaemias : fever, fatigue, paleness, bleeding, bones pain,
neurological findings, anemia, low platelet levels, blasts in the peripheral blood.
4) Various malignant tumours and disseminated cancers : associate fever, loss of
weight, specific symptoms that concern the affected organ, high ESR, anemia,
diagnostic tissue examination.