Fever of unknown origin (FUO) also known as Pyrexia of unknown origin (PUO) is a rise in temperature over 38 degree Celsius or over 101 Fahrenheit, frequently for at least 3 weeks and failure to reach a diagnosis or reason of fever, even after 1 week of inpatient investigation.
TYPES
- Classical FUO
Rise in temperature or unexplained fever. Some infection or Neoplasm or other factors may be the reason for this fever. - Nosocomial FUO
Unexplained fever after hospitalization. It’s a hospital-acquired fever that means, we admit the patient in a hospital for some other reasons rather than fever but begins to have an unexplained fever.
Conditions such as- Appendicitis
- Enterocolitis
- Pulmonary embolism, etc.
- HIV associated FUO
An HIV-infected person is prone to get infections easily. It may cause fever in such patients. - Immune compromised FUO
Fever is not a disease But, it is a symptom. Persons who are already immune-compromised get easily infected by any pathogens.
CAUSES OF FUO?
The reason behind the infection only comes into light because of investigations or tests.
1. Bacterial Infection
Tuberculosis, Typhoid, Syphilis,
2. Viral Infections
HIV, Chronic Hepatitis, Q fever
3. Parasitic Infections
Malaria, Amebiasis, toxocariasis
4. Fungal Infection
Candidiasis, Histoplasmosis
5. Neoplasms
Lymphoma, Leukemia, Colon Carcinoma, Hepatoma, Atrial Myxoma.
6. Inflammatory Reasons
Rheumatoid Arthritis, Sarcoidosis, Polyarteritis Nodosa, Crohn’s
disease, Inflammatory Bowel Disease (IBD)
7. Other Reasons
Drug Fever, Factitious Fever, Periodic Fever.
SYMPTOMS
It accompanies symptoms with the reason of the fever.
- Chill
- Nasal congestion
- Headache
- Weakness
- Fatigue
- Lethargy
- Anorexia
- Malaise
- Joint pain
- Body ache
WHAT YOU SHOULD DO?
If you are suffering from fever from prolonging time, Seek the advice of your Doctor.
DOCTOR MAY ASK SOME BASIC QUESTIONS
- Have you visited somewhere in last 15 days?
- Are you allergic to some food?
- Are you suffering from any other problem rather than fever?
- What is your occupation?
- Any Recent dental treatment?
- Ask you about the pattern of your fever?
- Do you have any history of accidents, surgery or any other Gynecologic procedures?
Your doctor can also prescribe you to some basic lab tests which will help to diagnose the disease more clearly.
DIAGNOSTIC TEST FOR FUO?
CULTURE TEST
Blood, urine or sputum culture test for the diagnosis of particular bacteria, parasite or fungi.
COMPLETE BLOOD PICTURE
With this test, it’s very easy to know the HB level, total Red Blood Cells count, White Blood Cells count and platelet count.
LIVER FUNCTION TEST
To know the normal function of liver.
To know the Bilirubin level in suspicion of jaundice.
RENAL FUNCTION TEST
To know the proper function of the kidney.
SEROLOGICAL EXAMINATIONS
Serological tests such as WIDAL test, ASO Titre, HIV-ELISA test, TPHA test, VDRL test, ANCA test.
IMAGING TEST
CT SCAN
MRI FOR
To check any kind of tumour or neoplastic growth.
To check abscesses, meningitis, Organ enlargement.
ECG OR ECHOCARDIOGRAM
In suspicion of infective endocarditis.
TREATMENT
Until we make the diagnosis, we give symptomatic or supportive treatment. According to American Family Physician, they usually discharge people with FUO without a definitive diagnosis in almost up to 50% of cases. In many of these undiagnosed cases, FUO spontaneously resolves itself with time.
Nonsteroidal anti-inflammatory drugs (NSAIDs) and Antihistamines drugs may also treat FUOs that have no trace of underlying causes.
In many people, these medications can help reduce the fever itself. People having fevers with immune-deficient origin may get a treatment with broad-spectrum antibiotics in bacterial infection.
In, almost 20% to 40% of cases infections are responsible for all fevers of unknown origin. People with HIV-associated fevers, treatment should be focused on treating HIV with antiviral drugs. After that, we will address any associated symptoms or complications that may stem from it.
