ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

Pyrexia Of Unknown Origin (PUO) And Diagnostic Methods In Infectious Diseases

Updated on March 22, 2014

Severity Of Fever

Source

Etiology And Diagnosis Of Pyrexia

When the temperature is raised above 38.30C for more than two weeks without the cause being detected by physical examination or laboratory tests, it comes under the definition of PUO. This presents one of the most difficult diagnostic problems in medicine. Atypical manifestations of common illnesses are responsible for the majority of such cases. Though in the vast majority of cases, the cause can be detected by repeated investigations and observation, in a few the cause may be obscure even at autopsy.

Etiology

  1. Occult tuberculosis: Affection of the lymph nodes, vertebrae, joints, intestines, mesentery, liver and rarely the lungs and pleura may remain latent without any obvious local symptoms. Fever may be the only presenting symptom, and all investigations including the tuberculin test may be negative. The local lesions may become evident only after several weeks or months.
  2. Chronic suppurative lesions of the liver, pelvic organs, urinary tract, peritoneum, gall bladder, brain, lungs and bones and joints may all manifest as prolonged fever without producing local symptoms. Other foci of suppuration which are likely to be missed are the perinephric, subdiaphragmatic and pelvic absecces, and paranasal sinuses. Dental sepsis, which is likely to be considered insignificant, may at times be the cause of prolonged pyrexia.
  3. Viral Infections: Infectious mononucleosis, cytomegalovirus infections, viral hepatitis.
  4. Connective tissue disorders: Systemic lupus erythematosus, polyarteritis nodosa, rheumatoid arthritis, rheumatic fever, giant cell arteritis.
  5. Chronic infections: syphilis, hepatic amoebiasis, malaria, filariasis, leprosy, recurrent bacteremias in cirrhosis, liver infective endocarditis, bruccellossi and sarcoidosis.
  6. Hematological malignancies: Leukemias, lymphomas, multiple myeloma
  7. Other malignant lesions: Tumours of the gastrointestinal tract, liver, lungs and kidneys
  8. Allergic conditions: Drug allergy, other external allergens.
  9. Miscellenious conditions: Hemolytic anemia, multiple venous thrombosis, recurrent pulmonary embolism, anxiety state, dehydration in infants.
  10. Fictitious fever: Fever may be self induced by patients with psychological abnormalities with a view to deceive the physician and gain sympathy. Such patients may either infect themselves with bacteria to produce fever or they may devise methods to make the thermometer record a high temperature even when they are normal.

Diagnosis

Careful attention to history and repeated physical examination serve to reveal the etiology in many cases. The investigations have to be repeated at weekly intervals and any fresh clinical clue such as appearance of a lymph node or local tenderness should suggest the appropriate investigation. Despite prolonged observation and repeated investigations, a small proportion of cases remain undiagnosed. In them, the fever may subside either spontaneously or with symptomatic treatment.

A Child With Mild Fever

Source

Diagnostic Methods In Infectious Diseases

Laboratory tests commonly undertaken in the diagnosis of infections include the following:

  1. Microscopic examination to detect the causative organisms in exudates, secretions, excretion and body fluids by staining, immunofluorescent procedures, phase contast, dark ground or electron microscopy.
  2. Isolation of the organism by culture/animal inoculation.
  3. Demonstration of antibodies by serology.
  4. Demonstrating hypersensitivity states by skin tests.
  5. Histopathology and isolation of the organism using biopsy specimen.

List of Materials To Be Sent To The Laboratory For Isolation Of Common Bacterial Pathogens

Probable infecting agent
Specimen to be sent
Staphylococci
Exudates, tissue, blood, serum, swabs from anterior nares and throat (in case of carriers)
Streptococci
 
i. streptococcus Pyogenes
Exudates, throat swabs, high vaginal swab, blood, serum
ii. other beta and alpha hemolytic streptococci
Exudates, blood culture
Pneumococci
Sputum, CSF, blood culture, exudates, throat swab.
Meningococci
CSF, blood cultures, postnasal swabs (in carriers)
Gonococci
Exudates from urethra, cervix, rectum, throat swab, conjunctiva, serum
Bacillus Anthracis
Exudate, blood culture, sputum, feces
Corynebacterium diphtheriae
Membrane (exudates) throat swab, nasal swab, ulcer swab
Clostridia
Exudate, tissue, blood culture, food, feces
Mycobacteria
 
i. Tuberculosis
Sputum, exudates, CSF, urine, biopsy material
ii. Leprosy
Skin- clipping, sputum, biopsy nerve and nasal swab.
Leptospirae
Blood, Serum, Urine
Treponema Pallidum
Exudate, Serum
Salmonella
 
i. Enteric fever
Blood, feces, urine, serum
ii. Food poisoning
Feces, vomit, food, blood cultures
Shigella
Feces
Vibrio cholera and Eltor strain
Feces
Brucella
Blood, serum
Yersinia Pestes
Exudate, aspirate from bubo, blood, sputum, serum
Hemophilus Influenzae
Sputum, CSF, blood, exudates from eye
Bordetella Pertussis
Pharyngeal or laryngeal swab, cough plate, throat washings
Pseudomonas And Proteus
Urine, exudates, CSF and Urine, exudates

Careful recording of history, physical examination and necessary supportive laboratory investigations form the cornerstone of proper diagnosis. A provisional diagnosis has to be concluded on history of patient, clinical examinations and preliminrary investigations such as urinalysis, blood counts and X-rays. Further investigations have to be planned depending on the provisional diagnosis. To get reliable laboratory reports, the collection and transport of the specimen should be properly done. Laboratory results should be interpreted in the light of the clinical findings.

© 2014 Funom Theophilus Makama

Comments

    0 of 8192 characters used
    Post Comment

    No comments yet.

    working

    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, hubpages.com uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at: https://hubpages.com/privacy-policy#gdpr

    Show Details
    Necessary
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the googleapis.com or gstatic.com domains, for performance and efficiency reasons. (Privacy Policy)
    Features
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Marketing
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Statistics
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)