Approach to history taking in a patient with fever

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1. APPROACH TO HISTORY TAKING IN A PATIENT WITH FEVER 2012 School of Clinical Medicine Clinical Skills NRMSM UKZN Dr RM Abraham

2. OVERVIEW Introduction Thermoregulation Pathophysiology of fever Aetiology /Differential diagnosis of fever Types of fever Pyrexia of Unknown origin(PUO) Factitious fever History taking in a febrile patient

3. INTRODUCTION FEVER(Pyrexia) Is an elevation of body temperature above the normal circadian range (daily variation) as a result of a change in the thermoregulatory center located in the anterior hypothalamus and pre-optic area (i.e. an increase in the hypothalamic set point of 37 C ) due to infection, metabolic derangements or increased cell destruction.

4. THERMOREGULATION Body temperature is controlled in the hypothalamus, which is directly sensitive to changes in core temperature The normal 'set-point' of core temperature is tightly regulated within 37 ± 0.5°C, as required to preserve normal function of many enzymes and other metabolic processes.

5. THERMOREGULATION In a hot environment sweating is the main mechanism for increasing heat loss. This usually occurs when the ambient temperature rises above 32.5°C or during exercise

6. PATHOPHYSIOLOGY OF FEVER The initiation of fever begins : when exogenous or endogenous stimuli are presented to specialized host cells, principally monocytes and macrophages ,they will then stimulate the synthesis and release of various pyrogenic cytokines including : 1)interleukin-1, interleukin-6 2)TNF- α , and 3)IFN- γ.

7. PATHOPHYSIOLOGY OF FEVER Exogenous pyrogens : stimuli from outside the host like : microorganism, their products, or toxins and it is called Endotoxin Endotoxin : lipopolysaccharide ( LPS) LPS: is found in the outer membrane of all gram negative organisms Action : 1) through stimulation of monocytes and macrophages 2) direct on endothelial cell of the brain to produce fever

8. PATHOPHYSIOLOGY OF FEVER Endogenous pyrogens : polypeptides that are produced by the body ( by monocytes and macrophages ) in response to stimuli that is usually triggered by infection or inflammation stimuli

9. PATHOPHYSIOLOGY OF FEVER Pyrogens: Substances that cause fever are called pyrogens Cytokines : Cytokines are regulatory polypeptides that are produced by 1) monocytes / macrophages 2) lymphocytes 3) endothelial and epithelial cell and hepatocytes

10. PATHOPHYSIOLOGY OF FEVER The most important cytokines are : Interleukin 1  and 1 (The most pyrogenic) Tumor necrosis factor  Interferon gamma Interleukin 6 (The least pyrogenic) cytokines>fever develop within 1hr of infection

11. PATHOPHYSIOLOGY OF FEVER Cytokine-receptor interactions in the pre-optic region of the anterior hypothalamus activate phospholipase A. This enzyme liberates plasma membrane arachidonic acid as substrate for the cyclo-oxygenase pathway. The resulting mediator, prostaglandin E2 , then modifies the responsiveness of thermosensitive neurons in the thermoregulatory centre. The PGE2 in the brain then stimulates the rapid release of cAMP from glial cells, this release then induces the release of neurotransmitters that raises the thermoregulatory set point in the hypothalamus . These events then lead to increased body heat content and fever .  

12. FEVER INFECTIONS MALIGNANCIES AUTOIMMUNE CONDITIONS- JOINT/CONNECTIVE TISSUE DISEASE OTHERS Typhoid Fever Hepatitis A & B Leptospirosis Tuberculosis Malaria Leukemia Lymphoma Rheumatoid arthritis Rheumatic fever Systemic lupus erythematosus Vasculitis Drug-induced fever 14 Aetiology/Differential diagnosis

13. TYPES OF FEVER The pattern of temperature changes may occasionally hint at the diagnosis: Continuous fever : Temperature remains above normal throughout the day and does not fluctuate more than 1 °C in 24 hours, e.g. lobar pneumonia , typhoid fever , urinary tract infection , brucellosis Intermittent fever: The temperature elevation is present only for a certain period, later cycling back to normal(i.e. Normal temp. between fever episodes), e.g. malaria , pyaemia , or septicemia . Following are its types Quotidian fever, with a periodicity of 24 hours, typical of Plasmodium falciparum malaria Tertian fever (48 hour periodicity), typical of Plasmodium vivax or Plasmodium ovale malaria Quartan fever (72 hour periodicity), typical of Plasmodium malariae malaria.

14. TYPES OF FEVER Remittent fever : Temperature remains above normal throughout the day and fluctuates more than 1 °C in 24 hours, e.g. , infective endocarditis . Pel-Ebstein fever : A specific kind of fever associated with Hodgkin's lymphoma , being high for one week and low for the next week and so on. However, there is some debate as to whether this pattern truly exists.

15. PYREXIA OF UNKNOWN ORIGIN (PUO) A common presenting problem. Defined as a consistently elevated body temperature of more than 37.5  C persisting for more than 2 weeks with no diagnosis despite one week of initial investigations. The commonest cause of PUO is a common disease presenting atypically . As the duration of fever increases the likelihood of an infectious cause decreases. Among children, infections are the most common causes.

16. Aetiology and Epidemiology of PUO in developed countries Infections (30%) Sepsis- Abscess at any site; Cholecystitis / Cholangitis Urinary tract infection Dental and sinus infection Bone and joint infections Imported infections, e.g. Malaria, Dengue, Brucellosis Enteric or Typhoid fever Infective endocarditis Tuberculosis (particularly extrapulmonary) Viral infections (cytomegalovirus-CMV, Ebstein-Barr virus-EBV, human immunodeficiency virus-HIV), Hepatitis A and B and toxoplasmosis Fungal infections Malignancy (20%) Lymphoma and myeloma Leukaemia Solid tumours (renal, liver, colon, stomach, pancreas)

17. Connective tissue disorders (15%) Vasculitic disorders (including polyarteritis nodosa and rheumatoid disease with vasculitis) Systemic lupus erythematosis (SLE) Rheumatoid arthritis Rheumatoid fever Temporal arteritis Polymyositis Miscellaneous (20%) Inflammatory bowel disease Liver disease: Cirrhosis and granulomatous hepatitis Sarcoidosis Drug reactions Thyrotoxicosis Hypothalamic lesions Familial meditaranean fever No diagnosis or resolves spontaneously (15%)

18. FACTITIOUS FEVER This is defined as fever engineered by the patient by manipulating the thermometer and/or temperature chart apparently to obtain medical care. uncommon and typically presents in young women with a medical and nursing background. Examples include The dipping of thermometers into hot drinks to fake a fever. The factitious disorder is usually medical but may relate to a psychiatric illness with reports of depressive illness.

19. FACTITIOUS FEVER CLUES TO THE DIAGNOSIS OF FACTITIOUS FEVER A patient who looks well Absence of temperature-related changes in pulse rate Temperature > 41°C Absence of sweating during the period of fever Normal ESR and CRP despite high fever Useful methods for the detection of factitious fever include 1) Supervised (observed) temperature measurement 2) Measuring the temperature of freshly voided urine

20. HISTORY TAKING IN FEBRILE PATIENTS Using the Calgary Cambridge guide as a framework to interviewing patients. The most important step is taking a meticulous detailed history to explore the patients problems from three perspectives. Biomedical perspective- to understand the chronology of symptoms, analyse each symptom and review each system to localize the source of the fever. Contextual history- very important Patients perspective- to understand the patients interpretation of the illness. Systems review- This is a guide not to miss anything. Any significant finding should be moved to HPC or PMH depending upon where you think it belongs.

21. exploration of the patient’s problems to discover the:  biomedical perspective  the patient’s perspective  background information - context providing the correct type and amount of information aiding accurate recall and understanding achieving a shared understanding: incorporating the patient’s illness framework planning: shared decision making Initiating the session Gathering information Physical examination Explanation and planning Closing the session Providing structure Building the relationship preparation establishing initial rapport identifying the reasons for the consultation making organisation overt attending to flow using appropriate non-verbal behaviour developing rapport involving the patient ensuring appropriate point of closure forward planning a

22.   The content of the medical interview Patient’s problem list 1. 2. 3. Exploration of patient’s problems: Biomedical perspective sequence of events , symptom analysis , relevant systems review Patient’s perspective ideas , concerns, expectations , effects on life , feelings ICE Background information - context Past medical history Family history Personal and social history Drug and allergy history Systems review b

23. BIOMEDICAL PERSPECTIVE   Presenting complaints of a patient with fever Feeling hot A feeling of heat does not necessarily imply fever Rigors . profound chills accompanied by chattering of the teeth and severe shivering, implies a rapid rise in body temperature. Can be produced by : 1) brucellosis and malaria 2) sepsis with abscess 3) lymphoma Excessive sweating . Night sweats are characteristic of tuberculosis, but sweating from any cause is usually worse at night.

24. BIOMEDICAL PERSPECTIVE Recurrent fever. Source is often a focus of bacterial infection such as cholecystitis or cholangitis or urinary tract infection especially associated with an obstruction or calculi. Headache . Fever from any cause may provoke headache. Severe headache and photophobia, may suggests meningitis. Delirium . Mental confusion during fever is well described and relatively more common in young children and in old age. Muscle pain . Myalgia is characteristic of viral infections such as influenza, Malaria and brucellosis.

25. BIOMEDICAL PERSPECTIVE Symptom analysis for fever Verify presence of fever- True or factitious fever Duration- Acute or chronic Mode of onset- Abrupt or gradual Progression- Continuous or intermittent. If intermittent ask about frequency to determine the pattern. Severity- how it affects daily work/physical activities. Relieving and aggravating factors Treatment received or/and outcome Associated symptoms- Localizing symptoms may indicate the source of fever.

26. BIOMEDICAL PERSPECTIVE Respiratory tract symptoms : 1) Sore throat, nasal discharge, sneezing-URTI 2) Sinus pain and headache-suggests sinusitis 3) cough, sputum, wheeze or breathlessness-suggests a LRTI Genitourinary symptoms: 1) Frequency of micturition, dysuria, loin pain, and vaginal or urethral discharge-suggesting a) Urinary tract infection, b) Pelvic inflammatory disease and c) Sexually transmitted infection (STI)

27. BIOMEDICAL PERSPECTIVE Abdominal symptoms: diarrhea, with or without blood, weight loss and abdominal pain -suggesting a) Gastroenteritis, b) Intra-abdominal sepsis, c) Inflammatory bowel disease, d) Malignancy Skin rash: enquire about appearance and distribution as it may provide clues to the diagnosis- Macular- Measles,Rubella,toxoplasmosis Haemorrhagic- Meningococcal infections, viral haemorrhagic fever. Vesicular- Chickenpox, Shingles, herpes simplex Nodular- Erythema nodosum( TB and Leprosy) Erythematous- Drug rashes, Dengue fever

28. BIOMEDICAL PERSPECTIVE Joint symptoms: joint pain, swelling or limitation of movement is suggestive of active arthritis. A) distribution : mono , oligo or poly arthritis B) appearance : fleeting 1) infective arthritis- oligoarthritis 2) collagen vascular disease-fleeting 3) reactive arthritis

29. BIOMEDICAL PERSPECTIV E Constitutional symptoms: Weakness Fatigue Anorexia Change of weight Fever/chills Lumps Night sweats

30. CONTEXTUAL HISTORY Past Medical /Surgical History Start by asking the patient if they have any medical problems IHD/DM/Asthma/HT/RHD, TB/Jaundice/Fits e.g. if diabetic- mention time of diagnosis/current medication/clinic check up Past surgical/operation history E.g. time/place/ what type of operation. Note any blood transfusion / blood grouping. H/O dental extractions/circumcision & any excessive bleeding during these procedures. Patient known to have rheumatic heart disease is at risk to develop infective endocarditis if not given prophylaxis Any minor operations or procedures including endoscopies, dental interventions, biopsies. History of trauma/accidents E.g. time/place/ and what type of accident History of tattoo piercing

31. CONTEXTUAL HISTORY Drug and allergy History dosage, timing &how long. Drug fever is uncommon and therefore easily missed-The culprits include : penicillin and cephalosporin sulphonamide anti tuberculous agents anticonvulsants particularly phenytoin OCT/Vitamins/Traditional /Herbal medicine & alternative medicine such as acupuncture. Blood transfusion. Immunization against Hepatitis A &B, Typhoid fever. Malaria prophylaxis

32. CONTEXTUAL HISTORY Family History Any familial disease/running in families e.g. breast cancer, IHD, DM, Asthma, Arthritis Infections running in families as TB, Leprosy. Cholera, typhoid in case of epidemics.

33. CONTEXTUAL HISTORY Personal and Social History Smoking history - amount, duration & type- strong risk factor for IHD Alcohol history - amount, duration & type-Unhealthy alcohol use is associated with cardiomyopathy, CVA, liver cirrhosis, alcoholic hepatitis, hepatocellular carcinoma. Occupation, social & education background, family social support& financial situation, Social class. Home conditions-Water supply, Sanitation status in his home & surrounding, Geographic area of living, fresh-water swimming. Animals / birds in his/her house- exposure to birds (psittacosis) or animals (toxoplasmosis, brucellosis, leptospirosis) Consumption of unpasteurized milk or milk products (tuberculosis, brucellosis and Q fever). Sexual History- Unprotected exposure to sexual partner with STI, HIV Illicit drug usage- injections and sharing of needles (HIV, hepatitis B &C, infective endocarditis), site of injection (e.g Femoral vein-septic arthritis, ilio-psoas abscess)

34. CONTEXTUAL HISTORY Travel History Travel to an area known to be endemic for certain disease: Name of the area, duration of stay Onset of illness- (incubation period) 1 –10 Days- Malaria, Dengue, Salmonella 10 –21Days -Malaria,Typhoid,Brucella,HepatitisA Weeks-Months - Amoebiasis, HIV, Hepatitis Vital questions-(Always ask about foreign travel). a) Where have you been? …Endemic area or not ? b) What have you done? C) How long were you there? d) Did you have insect bites or contact with animals? e) Did you take precautions/prophylaxis against malaria? If the patient has been in an endemic area The most common diagnoses :Malaria, Typhoid fever, Viral hepatitis, Dengue fever Malaria must be excluded whatever the presenting symptoms

35. PATIENTS PERSPECTIVE Always ask the patient how he/she feels/thinks about the illness by analysing Ideas Concerns Feelings Expectations Effects on daily living

36. SYSTEMS REVIEW General Weakness Fatigue Anorexia Change of weight Fever/chills Lumps Night sweats

37. SYSTEMS REVIEW Cardiovascular Chest pain Paroxysmal Nocturnal Dyspnoea Orthopnoea Short Of Breath(SOB) Cough/sputum (pinkish/frank blood) Swelling of ankle(SOA) Palpitations Cyanosis

38. SYSTEMS REVIEW Gastrointestinal Appetite (anorexia/weight change) Diet Nausea/vomiting Regurgitation/heart burn/flatulence Difficulty in swallowing Abdominal pain/distension Change of bowel habit Haematemesis, melaena Jaundice

39. SYSTEMS REVIEW Respiratory System Cough(productive/dry) Sputum (colour, amount, smell) Haemoptysis Chest pain SOB/Dyspnoea Tachypnoea Hoarseness Wheezing

40. SYSTEMS REVIEW Urinary System Frequency Dysuria Urgency Hesitancy Terminal dribbling Nocturia Back/loin pain Incontinence Character of urine: color/ amount (polyuria) & timing Fever

41. SYSTEMS REVIEW Nervous System Visual/Smell/Taste/Hearing/Speech problem Head ache Fits/Faints/Black outs/loss of consciousness(LOC) Muscle weakness/numbness/paralysis Abnormal sensation Tremor Change of behaviour or psyche. Paresis.

42. SYSTEMS REVIEW Genital system Pain/ discomfort/ itching Discharge Unusual bleeding Sexual history Menstrual history – menarche/ LMP/ duration & amount of cycle/ Contraception Obstetric history – Para/ gravida/abortion

43. SYSTEMS REVIEW Musculoskeletal System Pain – muscle, bone, joint Swelling Weakness/movement Deformities Gait

44. THE END: REFERENCES Guyton's Textbook of Medical Physiology Davidson's Principles & Practice of Medicine Hutchinson's Clinical Methods Harrison’s Principles of Internal Medicine Google images