Fever
Fever is an elevation of body temperature above the normal range, typically exceeding 38.0°C (100.4°F), resulting from a cytokine-mediated upward resetting of the hypothalamic thermoregulatory set point in response to infection, inflammation, or other pathological stimuli.
Murtagh Diagnostic Strategy
| Category | Diagnosis | Key Discriminator | Cantonese Question / Finding | Probability |
|---|---|---|---|---|
| Probability Diagnosis | Upper respiratory tract infection (URTI) | Coryza, sore throat, low-grade fever, self-limiting [3] | 「有冇流鼻水、喉嚨痛、咳？」 | ~50% |
| Acute gastroenteritis | Diarrhoea, vomiting, short duration | 「有冇肚屙、嘔？」 | ~15% | |
| Urinary tract infection | Dysuria, frequency, suprapubic/flank pain | 「小便有冇赤痛、去得密？」 | ~10% | |
| Serious Not To Miss | Pneumonia | Productive cough, tachypnoea, high fever, consolidation signs [3] | 「有冇氣促、痰帶顏色？」Crackles on auscultation | ~5% |
| Sepsis / Bacteraemia | Rigors, tachycardia, hypotension, ill-appearing | 「有冇凍到震？」 Assess vitals | ~2% | |
| TB | Chronic cough > 2 wk, night sweats, contact Hx, weight loss | 「咳咗幾耐？有冇接觸過肺癆病人？」 | ~1% | |
| Malignancy (lymphoma, leukaemia) | B-symptoms, lymphadenopathy, weight loss | 「有冇頸/腋下淋巴腫大？體重跌？」 | ~1% | |
| Meningitis / Encephalitis | Headache, neck stiffness, photophobia, altered consciousness [9] | 「有冇頸硬、怕光？」Kernig/Brudzinski sign | < 1% | |
| Dengue / Malaria (travel-related) | Travel to endemic area within incubation period [6] | 「最近有冇去過東南亞／非洲？」 Tourniquet test for dengue | < 1% | |
| Infective endocarditis | Persistent fever + new murmur + risk factors (IVDU, valvular disease) [10] | 「有冇心臟病底？」New murmur, splinter haemorrhages | < 1% | |
| Pitfalls | Pyelonephritis (missed UTI) | Flank pain, high fever, may lack lower urinary Sx | 「有冇腰痛？」Renal angle tenderness | ~5% |
| Abscess (dental, hepatic, pelvic) | Swinging fever, localised pain/swelling | 「有冇牙痛？肚右邊痛？」 | ~2% | |
| Kawasaki disease (children) | Fever ≥ 5 days + conjunctivitis, rash, strawberry tongue, lymphadenopathy [11] | 「BB發燒幾多日？眼有冇紅？嘴唇有冇紅腫裂？」 | < 1% | |
| Masquerades | Drug fever | Temporal relationship to new drug, diagnosis of exclusion [8] | 「最近有冇開始食新藥？」Relative bradycardia | ~2% |
| Connective tissue disease (SLE, Still's) | Joint pain, rash, multisystem involvement | 「有冇關節痛、面紅疹？」 | ~1% | |
| Hyperthyroidism | Heat intolerance, weight loss, tremor, tachycardia | 「有冇手震、心跳快、怕熱？」 | < 1% | |
| Trying to Tell Me Something? | Fear of serious illness (e.g. COVID, cancer) | Recent media scare or family death from cancer | 「你有冇擔心呢個發燒係嚴重嘅病？」 | ~20% |
| Sick-leave / insurance need | The RFC may be a certificate, not the fever | 「你今日嚟最主要想我幫你啲咩？」 | ~15% | |
| Anxiety / Health anxiety | Persistent worry disproportionate to findings | 「你最擔心嘅係咩？有冇嘢令你好大壓力？」 | ~10% |
| Time | Task | Cantonese Key Phrases | Why It Scores Marks |
|---|---|---|---|
| 0:00–0:30 | Friendly opening, build rapport | 「你好，我係今日嘅醫生，點稱呼你？」「今日有咩嘢唔舒服想睇下？」 | Sets interpersonal tone; marks for greeting and open-ended start |
| 0:30–1:30 | HPI: symptom analysis — onset, duration, pattern, degree, associated Sx | 「幾時開始發燒？燒到幾多度？有冇時高時低？有冇探過熱？」「有冇凍親、成身痠痛、頭痛、出疹？」「有冇咳、痰、流鼻水、喉嚨痛？」「有冇肚痛、肚屙、嘔、小便赤痛？」 | Captures chief complaint + HPI systematically |
| 1:30–2:30 | Red flags + focused systems review | 「有冇頸硬、怕光、神志唔清？」「有冇氣促、心口痛？」「有冇出血、瘀斑？」「體重有冇跌咗？有冇夜晚出汗？」 | Screens serious/not-to-miss diagnoses |
| 2:30–3:30 | TOCC, PMH, drug Hx, allergy, FH, social | 「最近有冇去過旅行？做咩嘢工作？身邊有冇人病咗？」「有冇長期病患、食緊咩藥？有冇藥物敏感？」「屋企人有冇類似情況？」「有冇飲酒、食煙？」 | TOCC is high-yield for fever [1]; captures DDx and context |
| 3:30–4:30 | ICE — uncover hidden agenda | 「你自己覺得係咩原因？」(Idea)「你最擔心嘅係咩？」(Concern)「你今日嚟最希望醫生可以點幫你？」(Expectation) | Marks specifically awarded for ICE; "Why today?" reveals the real reason for consultation |
| 4:30–5:15 | Summarise back to patient | 「等我整理一下：你發燒咗X日，有XX症狀，冇乜嘢嚴重嘅警號，你擔心XXX——係咪咁？」 | Shows active listening; marks for summarising |
| 5:15–6:00 | Explain plan, safety-net, close | 「我初步估計係…… 我建議做吓檢查/食吓藥。如果燒持續超過三日、或者出現XXXX，一定要返嚟睇。有冇嘢想問？」 | Safety-net statement is a must; empathic close |
Hidden agenda tip: Ask 「點解今日先嚟睇？」or 「有冇嘢特別擔心？」— the patient may fear cancer (lymphoma), worry about infecting a newborn at home, or need a sick-leave certificate. The RFC is often not "fever" itself but the underlying worry.
| Domain | English Question | Cantonese Question | Why It Matters | If Positive, Think Of |
|---|---|---|---|---|
| Onset/Duration | When did the fever start? How many days? | 「幾時開始發燒？燒咗幾耐？」 | Acute ( < 7d) vs PUO ( > 7–21d) | PUO if > 3 weeks [2] |
| Degree/Pattern | Highest temp? Continuous or intermittent? | 「最高燒到幾多度？係持續定時斷時續？」 | Pattern helps DDx | Continuous → typhoid; intermittent → abscess; periodic → malaria |
| Rigors | Any shivering episodes? | 「有冇凍到成個人震？」 | Rigors suggest bacteraemia | Sepsis, abscess, IE, malaria |
| Resp Sx | Cough? Sputum? SOB? | 「有冇咳？有冇痰？痰係咩色？有冇氣促？」 | Commonest source in HK primary care | URTI, pneumonia [3] |
| ENT Sx | Sore throat? Runny nose? Ear pain? | 「有冇喉嚨痛、流鼻水、耳仔痛？」 | Points to URTI/pharyngitis | GAS pharyngitis (Centor criteria) [4] |
| Urinary Sx | Painful urination? Frequency? Flank pain? | 「小便有冇赤痛？有冇去得密？腰痛？」 | UTI is common occult fever source | UTI, pyelonephritis |
| GI Sx | Diarrhoea? Vomiting? Abdo pain? | 「有冇肚屙、嘔、肚痛？」 | Gastroenteritis, hepatitis, appendicitis | Acute gastroenteritis, hepatitis A/E [5] |
| Skin/Rash | Any rash or skin lesion? | 「身上有冇出疹、紅腫？」 | Rash + fever narrows DDx | Viral exanthem, cellulitis, dengue, Kawasaki (paeds) |
| Meningism | Neck stiffness? Photophobia? Confusion? | 「有冇頸硬、怕光、神志唔清醒？」 | Red flag — meningitis/encephalitis | Urgent referral |
| Weight loss / Night sweats | Unintentional weight loss? Drenching night sweats? | 「體重有冇無端端跌咗？夜晚有冇成身濕晒汗？」 | B-symptoms → malignancy / TB | Lymphoma, TB |
| TOCC | Travel? Occupation? Contact? Cluster? | 「最近有冇去過旅行？做咩工作？身邊有冇人病？有冇一齊病？」 | High-yield GC slide point [1][6] | Dengue/malaria (travel); TB (contact); nosocomial (occupation) |
| Sexual Hx | Any new sexual partners? STI risk? | 「有冇新嘅性伴侶？」(ask sensitively) | Acute HIV, STI, PID | Acute retroviral syndrome, PID |
| PMH | Chronic illness? Immunosuppression? DM? | 「有冇長期病患？糖尿？有冇食緊抑制免疫力嘅藥？」 | Immunocompromised host changes DDx | Opportunistic infection [7] |
| Drug Hx | Recent antibiotics? New medications? Chemo? | 「最近有冇食過抗生素？新藥？做緊化療？」 | Drug fever; neutropenic fever | Drug fever, febrile neutropenia [7][8] |
| Allergy | Any drug allergy? | 「有冇藥物敏感？」 | Safety before prescribing | — |
| Family Hx | Family members ill? TB contact? | 「屋企人有冇類似病徵？有冇肺癆接觸史？」 | Cluster → infection; FH of TB | TB |
| Smoking/Alcohol | Smoke? Alcohol? IVDU? | 「有冇食煙、飲酒？有冇打針吸毒？」 | IVDU → IE, hepatitis | IE (tricuspid), HBV/HCV/HIV |
| Functional impact | Can you work/go to school? Sleep OK? | 「有冇影響返工/返學？瞓得好唔好？」 | Social/functional problem for CRF | Sick-leave need, school absence |
| Health-seeking | What have you tried? Seen other doctors? | 「有冇睇過其他醫生？食咗咩藥？」 | Prior Tx failure raises concern | Resistant organism, alternative Dx |
Case Report Form Answer Builder
- CC: "Fever × ___ days"
- HPI high-yield points:
- Onset, duration, maximum temperature, pattern (continuous/intermittent/remittent)
- Associated symptoms by system: respiratory (cough, sputum, sore throat), urinary (dysuria, frequency), GI (diarrhoea, vomiting), CNS (headache, neck stiffness), skin (rash)
- Rigors, chills, night sweats, weight loss
- TOCC: Travel, Occupation, Contact history, Clustering [1][6]
- Self-treatment and response to antipyretics
- Red flags screened and documented as negative if absent
- Likely RFC examples:
- "Patient worried that fever is caused by a serious illness (e.g., cancer/COVID)"
- "Fever not resolving despite self-medication for 5 days"
- "Needs medical certificate for sick leave"
- "Mother concerned about febrile convulsion in child"
- How to phrase: State the patient's reason, not the disease. E.g., "Persistent fever not responding to paracetamol for 5 days, worried about serious underlying cause."
| Component | Likely Example | Exact Wording for CRF |
|---|---|---|
| Idea | "I think I caught a cold from my colleague" | Patient thinks fever is due to catching a cold from a sick colleague at work. |
| Concern | "I'm worried it could be something serious like cancer / COVID" | Patient is worried the prolonged fever may indicate a serious disease such as cancer. |
| Expectation | "I want blood tests to find out the cause" / "I need a sick-leave cert" | Patient expects blood tests to identify the cause and a medical certificate for work. |
- In an FM station with short-duration fever + coryzal symptoms → Acute URTI (viral upper respiratory tract infection) is the most common diagnosis.
- Minimum supporting evidence: Low-grade fever, coryza (rhinorrhoea, nasal congestion), sore throat, cough, no red-flag signs, self-limiting course, contact history.
- If the stem gives urinary symptoms → UTI; productive cough + consolidation → pneumonia. Always match to the clinical cue.
| DDx | One Key Discriminator |
|---|---|
| 1. Acute tonsillitis/pharyngitis | Exudative tonsils, anterior cervical lymphadenopathy, absence of cough (Centor criteria) [4] |
| 2. Pneumonia | Productive cough, tachypnoea, unilateral crackles/bronchial breathing |
| 3. Urinary tract infection | Dysuria, urinary frequency, suprapubic tenderness; positive urine dipstick |
(Adjust to stem: if travel history → dengue/malaria; if child → otitis media / Kawasaki; if immunocompromised → opportunistic infection)
| Domain | Problem |
|---|---|
| Biological | Acute febrile illness (e.g. URTI) causing malaise, dehydration risk |
| Psychological | Anxiety about serious underlying diagnosis (cancer/COVID worry) |
| Social/Functional | Inability to work / attend school; need for sick leave; potential transmission to household contacts |
| Diagnosis/DDx | Best Supporting Physical Sign | How to Elicit It | Why It Supports This Dx |
|---|---|---|---|
| URTI (most likely) | Pharyngeal erythema ± nasal mucosal congestion | Inspect oropharynx with tongue depressor and light; examine nasal mucosa | Confirms upper airway inflammation consistent with viral URTI |
| Acute tonsillitis | Tonsillar exudate + tender anterior cervical lymphadenopathy | Inspect tonsils; palpate anterior cervical chain | Exudate + adenopathy = Centor criteria for GAS pharyngitis |
| Pneumonia | Unilateral crackles / bronchial breathing on auscultation | Auscultate lung fields posteriorly, compare both sides | Focal signs indicate consolidation |
| UTI / Pyelonephritis | Suprapubic tenderness / renal angle tenderness | Palpate suprapubic area; percuss renal angles (costo-vertebral angle) | Tenderness localises infection to urinary tract |
| Meningitis | Positive Kernig sign / neck stiffness | Flex hip to 90°, attempt to extend knee — positive if pain/resistance; passively flex neck | Meningeal irritation = urgent referral |
| Infective endocarditis | New cardiac murmur (regurgitant) | Auscultate all four valve areas with bell and diaphragm | New murmur in context of persistent fever → Modified Duke major criterion [10] |
| Drug fever | Relative bradycardia despite fever | Measure pulse and temperature simultaneously — expect ↑10 bpm per °C; if not → relative bradycardia | Dissociation between fever and heart rate suggests drug fever [8] |
Top Traps That Lose Marks
- Forgetting TOCC — Travel, Occupation, Contact, Clustering is the single most tested history point for fever in GC slides [1][6]. Not asking it = losing easy marks.
- Missing red flags — Neck stiffness, petechial rash, rigors with hypotension, altered consciousness → must be asked and documented.
- Writing "fever" as the RFC — The RFC should reflect why the patient came today, not just the symptom. Think: "Worried about cancer," "Needs sick leave," "Fever not settling."
- Not eliciting ICE — Marks are explicitly allocated. Use the exact three questions.
- Ignoring drug history — Drug fever and febrile neutropenia post-chemo are commonly tested pitfalls [7][8].
- Not asking about rash in children — Kawasaki disease (fever ≥ 5 days) and viral exanthems are paediatric pitfalls [11].
- Forgetting to safety-net — Always give return criteria: 「如果燒超過三日唔退、或者出現頸硬、出疹、神志不清，一定要即刻返嚟急症室。」
Must-Not-Miss Red Flags → Urgent Referral:
- Meningism (neck stiffness, photophobia, altered consciousness)
- Petechial/purpuric rash (meningococcaemia)
- Haemodynamic instability (sepsis/septic shock)
- Neutropenic fever (ANC < 0.5 × 10⁹/L) [7]
- Fever > 5 days in a child without source (Kawasaki) [11]
- Fever in infant < 90 days → always requires urgent workup [12]
Safety-net line (shortest safe version):
「如果食完退燒藥都唔退燒、或者出現新嘅症狀例如出疹、頸硬、氣促、神志變差，請即刻去急症室。三日內唔好轉都要返嚟覆診。」
High Yield Summary
What to ASK: Symptom analysis (onset, duration, degree, pattern, associated Sx by system) → Red flags (meningism, petechiae, rigors, haemodynamic instability) → TOCC → PMH/Drug Hx (drug fever, immunosuppression) → ICE (three explicit questions) → Functional impact.
What to WRITE on Case Report Form:
- CC: "Fever × __ days" with key HPI points
- RFC: The patient's reason, not the disease (e.g., "worried about serious cause of persistent fever")
- ICE: Idea/Concern/Expectation in the patient's own words
- Most likely Dx: Match to the stem (usually URTI in FM)
- DDx: Three alternatives with discriminators
- Biopsychosocial: One biological + one psychological + one social problem
- Physical sign: The ONE sign that best supports your most likely diagnosis
What NOT to MISS: TOCC, meningism screen, drug fever, Kawasaki in children, neutropenic fever, safety-netting.
Active Recall - Family Medicine Clinical Test
[1] Lecture slides: GC 048. Fever.pdf — TOCC history framework for fever [2] Senior notes: Block A - Fever.pdf — Definition of PUO [3] Lecture slides: GC 052. Fever and purulent sputum.pdf — Respiratory causes of fever [4] Senior notes: Ryan Ho Respiratory.pdf (p51) — Centor criteria for GAS pharyngitis [5] Senior notes: Block A - Jaundice after raw oysters_ acute hepatitis.pdf — Hepatitis A/E presentation with fever [6] Lecture slides: GC 103. Fever after travelling.pdf — Travel-related fever, dengue/malaria [7] Lecture slides: GC 102. Fever after chemotherapy infections in immunocompromised hosts.pdf — Neutropenic fever [8] Senior notes: Maksim Surgery Notes.pdf (p31) — Drug fever, post-op fever ("5 Ws") [9] Lecture slides: GC 051. Fever and confusion_meningitis and encephalitis; suppurative brain infection.pdf [10] Senior notes: Block A - Fever and a murmur_ Valvular heart diseases; Infective endocarditis.pdf — IE clinical features, Modified Duke criteria [11] Senior notes: Jerry's immunodeficiencies.pdf (p6) — Kawasaki disease in child with fever [12] Paediatrics: The febrile infant (younger than 90 days of age)_ Definition of fever - UpToDate.pdf — Fever definition in young infants
Skin Injury
Skin injury is damage to the integumentary tissue caused by mechanical, thermal, chemical, or radiation forces, ranging from superficial abrasions to full-thickness wounds involving the epidermis, dermis, and underlying structures.
Feeling Anxious
Feeling anxious is a normal emotional response characterized by apprehension, worry, and physiological arousal in anticipation of perceived threats or stressful situations, which becomes clinically significant when disproportionate and functionally impairing.