This presentation covers fever, its pathogenesis, different types of fever. Also covers fuo, its classification and causes.

3. Temperature Of Blood. THE BALANCE OF BODY HEAT

4. Normal Body Temperature 36.8 ± 0.4°C Or 98.2 ± 0.7°F So, Normal Oral temp.= 36.4 to 37.2°C OR 97.5 to 99°F CircadianRhythm= 0.5°C Minimum Temp at 6 A.M. Maximum Temp at evening. [ 4-6 P.M. ]

5. Different Places to Record Temp. ORAL : Usually done in conscious patient. Thermometer kept under the tongue. Slightly lower than actual core temperature. RECTAL : Done in children, elderly, unconscious patient. Gives the core body temperature.

6. AXILLARY : Should be avoided. Can be done in children under 5yrs. TYMPANIC : Measures radiant heat from tympanic mem & nearby. Accurate but difficult. RECTAL TEMP = 0.4 + ORAL TEMP. = 0.8 + TYMPANIC TEMP.

7. THERMOMETER :

9. FEVER : A.M. Temperature of > Or P.M. Temperature of > 37.2°C Or >98.9°F Or 37.7°C Or >99.9°F WITH INCREASE IN HYPOTHALAMIC SET POINT.

10. PATHOGENESIS EXOGENOUS PYROGENS Microbial Products Microorganisms Microbial toxins Act on Macrophages & other cells ENDOGENOUS PYROGENS Peripheral Manifestations HYPOTHALAMIC ENDOTHELIUM PGE2 THERMOREGULATORY SET POINT cAMP

12. Blood flows away from periphery.

13. “CHILLS.”

14. “SHIVERING”

15. Non Shivering Mech.

16. Behavioral AdjustmentCORE BODY TEMP. REACHES THE NEW SET POINT FEVER

18. Sweating

19. Behavioral Change BODY TEMPERATURE DROPS TO NORMAL

20. PATTERNS OF FEVER

21. SOME OTHER PATTERNS

22. GRADING OF TEMPERATURE Hypothermia = <35°C Or 95°F Subnormal Temp. = 35°C – 36.6°C FEVER Low Grade = Only evening rises. Mild = 37.2 – 37.8°C [99 – 100°F] Moderate = 37.8 – 39.4°C [100 – 103°F] High Grade = > 39.4°C [>103°F] Hyperpyrexia = > 41.5°C [>106. 7°F]

25. Definition : Petersdorf & Beeson : Temperature of >38.3°C on several occasions. Duration of fever of >3 weeks. & Failure to reach a diagnosis despite one week of inpatient investigation

26. New Criteria & Classification : 1. CLASSICAL FUO : Temperature of >38.3°C on several occasions. Duration of fever of >3 weeks. & Failure to reach a diagnosis despite 3 OPD visits, Or 3days in the hospital without elucidation of a cause, Or one week of intelligent & invasive ambulatory investigation.

27. 2. NOSOCOMIAL FUO : Temperature of >38.3°C on several occasions in a Hospitalized patient. Duration of fever of >3 weeks & 3 days of investigation including at least 2 days’ incubation of cultures 3. HIV Associated FUO : Temperature of >38.3°C on several occasions in a Hospitalized patient. Duration of fever of >4 weeks & 3 days of investigation including at least 2 days’ incubation of cultures

28. 4. NEUTROPENIC FUO : Temperature of >38.3°C on several occasions. Neutrophil count is <500/mcl Duration of fever of >3 weeks & 3 days of investigation including at least 2 days’ incubation of cultures.

29. CAUSES OF FUO:

31. CAUSES OF FUO:

32. Infectious Cause: BACTERIAL : Extra pulmonary TB, Abscess. IE, Osteomyelitis, HACEK . Sinusitis & dental inf. FUNGAL: Histoplasmosis, Cryptococcus Neoformans. VIRAL: EBV, CMV, HIV, Dengue, Hepatitis. PARASITIC: Amoebiasis, Malaria.

34. Commonest is Colon CA – in aged.

36. TB

38. Miscellaneous Disease: Drug Fever : Antimicrobial – B lactam CVS Drugs – Quinidine Antineoplastic drugs. Pulmonary Embolism : Hereditary Periodic Fever Syndrome. Factitious Fever. Thermoregulatory Disturbances : Habitual Hyperthermia:

39. Thank YOU….